Genome-wide association study identifies novel breast cancer susceptibility loci

Breast cancer exhibits familial aggregation, consistent with variation in genetic susceptibility to the disease. Known susceptibility genes account for less than 25% of the familial risk of breast cancer, and the residual genetic variance is likely to be due to variants conferring more moderate risks. To identify further susceptibility alleles, we conducted a two-stage genome-wide association study in 4,398 breast cancer cases and 4,316 controls, followed by a third stage in which 30 single nucleotide polymorphisms (SNPs) were tested for confirmation in 21,860 cases and 22,578 controls from 22 studies. We used 227,876 SNPs that were estimated to correlate with 77% of known common SNPs in Europeans at r2 > 0.5. SNPs in five novel independent loci exhibited strong and consistent evidence of association with breast cancer (P < 10(-7)). Four of these contain plausible causative genes (FGFR2, TNRC9, MAP3K1 and LSP1). At the second stage, 1,792 SNPs were significant at the P < 0.05 level compared with an estimated 1,343 that would be expected by chance, indicating that many additional common susceptibility alleles may be identifiable by this approach.

Prevalence and significance of hepatitis B virus (HBV) pre-S mutants in serum and liver at different replicative stages of chronic HBV infection

Several types of naturally occurring pre-S mutants in sera or liver tissues in patients with chronic hepatitis B virus (HBV) infection have been identified. To clarify the prevalence and significance of emergence of pre-S mutants, 140 sera and 18 resected livers from patients with HBV were studied. Replicative status was designated as high, intermediate, and low based on the HBV-DNA levels in serum or the expression of HBV antigens in liver. In vitro transfection and Western blot analysis were performed to characterize expression and secretion of HBsAg by the mutant constructs. Five major types (I to V) of pre-S deletion mutants in serum and liver and 2 types (VI and VII) in liver were identified. Pre-S mutant was 6.4% at high replicative phase, 13% at intermediate, and 37.5% at low or nonreplicative phases in serum. In livers, the same tendency existed: pre-S2 deletion mutants emerged and prevailed at a low replicative phase in hepatocytes that expressed a novel marginal pattern of HBsAg and usually clustered in groups. The deletion sequence of pre-S2 region coincides with human leukocyte antigen-restricted T- and B-cell epitopes. In vitro HBsAg was retained in the hepatocytes and synthesis and secretion of major surface antigen decreased for most of the pre-S mutants. Pre-S mutants prevailed with evolution of chronic HBV, probably under immune pressure. Emergence of pre-S mutants may account for the life-long persistence and discrepancy of HBsAg in serum and liver in HBV and may confer growth advantage in view of the clustering proliferation of hepatocytes harboring pre-S2 mutant.

The SH2 and SH3 domains of pp60src direct stable association with tyrosine phosphorylated proteins p130 and p110

Transformation of chicken embryo cells with the tyrosine kinase oncogene src results in the tyrosine phosphorylation of numerous cellular proteins. We have recently generated monoclonal antibodies to individual tyrosine phosphorylated cellular src substrates, several of which are directed to the phosphotyrosine-containing proteins p130 and p110. These proteins form stable complexes with activated variants of pp60src. Mutagenesis of the src homology domains (SH2 and SH3) of activated pp60src resulted in src variants with altered association with p130 and p110. Analysis of these variants showed that the SH3 domain was required for association of p110, while the SH2 domain contained residues necessary for the formation of the ternary complex involving p130, p110 and pp60src. Both the tyrosine phosphorylation status and pp60src association of p130 and p110 appeared to correlate, in part, with the extent of cell transformation. Biochemical analysis demonstrated that p130 and p110 were substrates of both serine/threonine and tyrosine kinases. In addition, p130 was redistributed from the nucleus to cellular membranes upon src transformation, whereas p110, which normally colocalized with cytoskeletal elements, was observed in adhesion plaques (podosomes) in src transformed cells. These data indicate that tyrosine phosphorylation of two different phosphoproteins may play a role during src transformation either by directing their interaction with pp60src, by redirecting subcellular distribution or both.

Newly identified stress-responsive protein kinases, Krs-1 and Krs-2

The activation of protein kinases is a frequent response of cells to treatment with growth factors, chemicals, heat shock, or apoptosis-inducing agents. However, when several agents result in the activation of the same enzymes, it is unclear how specific biological responses are generated. We describe here two protein kinases that are activated by a subset of stress conditions or apoptotic agents but are not activated by commonly used mitogenic stimuli. Purification and cloning demonstrate that these protein kinases are members of a subfamily of kinases related to Ste20p, a serine/threonine kinase that functions early in a pheromone responsive signal transduction cascade in yeast. The specificity of Krs-1 and Krs-2 activation and their similarity to Ste20p suggest that they may function at an early step in phosphorylation events that are specific responses to some forms of chemical stress or extreme heat shock.

Burkholderia phymatum is a highly effective nitrogen-fixing symbiont of Mimosa spp. and fixes nitrogen ex planta

* The ability of Burkholderia phymatum STM815 to effectively nodulate Mimosa spp., and to fix nitrogen ex planta, was compared with that of the known Mimosa symbiont Cupriavidus taiwanensis LMG19424. * Both strains were equally effective symbionts of M. pudica, but nodules formed by STM815 had greater nitrogenase activity. STM815 was shown to have a broader host range across the genus Mimosa than LMG19424, nodulating 30 out of 31 species, 21 of these effectively. LMG19424 effectively nodulated only nine species. GFP-marked variants were used to visualise symbiont presence within nodules. * STM815 gave significant acetylene reduction assay (ARA) activity in semisolid JMV medium ex planta, but no ARA activity was detected with LMG19424. 16S rDNA sequences of two isolates originally from Mimosa nodules in Papua New Guinea (NGR114 and NGR195A) identified them as Burkholderia phymatum also, with nodA, nodC and nifH genes of NGR195A identical to those of STM815. * B. phymatum is therefore an effective Mimosa symbiont with a broad host range, and is the first reported beta-rhizobial strain to fix nitrogen in free-living culture.

Effect of aging on morphology of organo-montmorillonite modified bitumen by atomic force microscopy

The morphology of unmodified and organo-montmorillonite modified bitumens was investigated by atomic force microscopy. The influence of thin film oven test and ultraviolet aging on the morphology of the binders was also analysed. The atomic force microscopy results showed that bitumen displayed a 'bee-like' structure and the dimension of the 'bee-like' structures was decreased to some extent with the introduction of organo-montmorillonite. Organo-montmorillonite showed a better interaction with the dispersed domains in comparison with the matrix in bitumen, which led to an obvious increase in the contrast between the dispersed domains and the matrix in bitumen. Compared with the unmodified bitumen, the single-phase trend in the organo-montmorillonite modified bitumen could be effectively prevented during thin film oven test and ultraviolet aging, indicating its good aging resistance which was in accordance with changes in physical properties of the organo-montmorillonite modified bitumen before and after aging.

FGFR2 variants and breast cancer risk: fine-scale mapping using African American studies and analysis of chromatin conformation

Genome-wide association studies have identified FGFR2 as a breast cancer (BC) susceptibility gene in populations of European and Asian descent, but a causative variant has not yet been conclusively identified. We hypothesized that the weaker linkage disequilibrium across this associated region in populations of African ancestry might help refine the set of candidate-causal single nucleotide polymorphisms (SNPs) previously identified by our group. Eight candidate-causal SNPs were evaluated in 1253 African American invasive BC cases and 1245 controls. A significant association with BC risk was found with SNP rs2981578 (unadjusted per-allele odds ratio = 1.20, 95% confidence interval 1.03-1.41, P(trend) = 0.02), with the odds ratio estimate similar to that reported in European and Asian subjects. To extend the fine-mapping, genotype data from the African American studies were analyzed jointly with data from European (n = 7196 cases, 7275 controls) and Asian (n = 3901 cases, 3205 controls) studies. In the combined analysis, SNP rs2981578 was the most strongly associated. Five other SNPs were too strongly correlated to be excluded at a likelihood ratio of < 1/100 relative to rs2981578. Analysis of DNase I hypersensitive sites indicated that only two of these map to highly accessible chromatin, one of which, SNP rs2981578, has previously been implicated in up-regulating FGFR2 expression. Our results demonstrate that the association of SNPs in FGFR2 with BC risk extends to women of African American ethnicity, and illustrate the utility of combining association analysis in datasets of diverse ethnic groups with functional experiments to identify disease susceptibility variants.

Risk of estrogen receptor-positive and -negative breast cancer and single-nucleotide polymorphism 2q35-rs13387042

BACKGROUND

A recent genome-wide association study identified single-nucleotide polymorphism (SNP) 2q35-rs13387042 as a marker of susceptibility to estrogen receptor (ER)-positive breast cancer. We attempted to confirm this association using the Breast Cancer Association Consortium.

METHODS

2q35-rs13387042 SNP was genotyped for 31 510 women with invasive breast cancer, 1101 women with ductal carcinoma in situ, and 35 969 female control subjects from 25 studies. Odds ratios (ORs) were estimated by logistic regression, adjusted for study. Heterogeneity in odds ratios by each of age, ethnicity, and study was assessed by fitting interaction terms. Heterogeneity by each of invasiveness, family history, bilaterality, and hormone receptor status was assessed by subclassifying case patients and applying polytomous logistic regression. All statistical tests were two-sided.

RESULTS

We found strong evidence of association between rs13387042 and breast cancer in white women of European origin (per-allele OR = 1.12, 95% confidence interval [CI] = 1.09 to 1.15; P(trend) = 1.0 x 10(-19)). The odds ratio was lower than that previously reported (P = .02) and did not vary by age or ethnicity (all P > or = .2). However, it was higher when the analysis was restricted to case patients who were selected for a strong family history (P = .02). An association was observed for both ER-positive (OR = 1.14, 95% CI = 1.10 to 1.17; P = 10(-15)) and ER-negative disease (OR = 1.10, 95% CI = 1.04 to 1.15; P = .0003) and both progesterone receptor (PR)-positive (OR = 1.15, 95% CI = 1.11 to 1.19; P = 5 x 10(-14)) and PR-negative disease (OR = 1.10, 95% CI = 1.06 to 1.15; P = .00002).

CONCLUSION

The rs13387042 is associated with both ER-positive and ER-negative breast cancer in European women.

Chk2-dependent phosphorylation of XRCC1 in the DNA damage response promotes base excision repair

The DNA damage response (DDR) has an essential function in maintaining genomic stability. Ataxia telangiectasia-mutated (ATM)-checkpoint kinase 2 (Chk2) and ATM- and Rad3-related (ATR)-Chk1, triggered, respectively, by DNA double-strand breaks and blocked replication forks, are two major DDRs processing structurally complicated DNA damage. In contrast, damage repaired by base excision repair (BER) is structurally simple, but whether, and how, the DDR is involved in repairing this damage is unclear. Here, we demonstrated that ATM-Chk2 was activated in the early response to oxidative and alkylation damage, known to be repaired by BER. Furthermore, Chk2 formed a complex with XRCC1, the BER scaffold protein, and phosphorylated XRCC1 in vivo and in vitro at Thr(284). A mutated XRCC1 lacking Thr(284) phosphorylation was linked to increased accumulation of unrepaired BER intermediate, reduced DNA repair capacity, and higher sensitivity to alkylation damage. In addition, a phosphorylation-mimic form of XRCC1 showed increased interaction with glycosylases, but not other BER proteins. Our results are consistent with the phosphorylation of XRCC1 by ATM-Chk2 facilitating recruitment of downstream BER proteins to the initial damage recognition/excision step to promote BER.

Ataxia telangiectasia mutated and checkpoint kinase 2 regulate BRCA1 to promote the fidelity of DNA end-joining

Homologous recombination (HR) and nonhomologous end-joining (NHEJ) are the two mechanisms responsible for repairing DNA double-strand breaks (DSBs) and act in either a collaborative or competitive manner in mammalian cells. DSB repaired by NHEJ may be more complicated than the simple joining of the ends of DSB, because, if nucleotides were lost, it would result in error-prone repair. This has led to the proposal that a subpathway of precise NHEJ exists that can repair DSBs with higher fidelity; this is supported by recent findings that the expression of the HR gene, BRCA1, is causally linked to in vitro and in vivo precise NHEJ activity. To further delineate this mechanism, the present study explored the connection between NHEJ and the cell-cycle checkpoint proteins, ataxia telangiectasia mutated (ATM) and checkpoint kinase 2 (Chk2), known to be involved in activating BRCA1, and tested the hypothesis that ATM and Chk2 promote precise end-joining by BRCA1. Support for this hypothesis came from the observations that (a) knockdown of ATM and Chk2 expression affected end-joining activity; (b) in BRCA1-defective cells, precise end-joining activity was not restored by a BRCA1 mutant lacking the site phosphorylated by Chk2 but was restored by wild-type BRCA1 or a mutant mimicking phosphorylation by Chk2; (c) Chk2 mutants lacking kinase activity or with a mutation at a site phosphorylated by ATM had a dominant negative effect on precise end-joining in BRCA1-expressing cells. These results suggest that the other two HR regulatory proteins, ATM and Chk2, act jointly to regulate the activity of BRCA1 in controlling the fidelity of DNA end-joining by precise NHEJ.

Breast cancer risk is associated with the genes encoding the DNA double-strand break repair Mre11/Rad50/Nbs1 complex

The evolutionarily conserved Mre11-Rad50-Nbs1 (MRN) complex, consisting of proteins encoded by the genes Mre11, Rad50, and Nbs1, was recently shown to play a crucial role in DNA double-strand break (DSB) repair by recruiting the nuclear protein kinase ataxia telangiectasia mutated to DSB sites, leading to activation of this DNA repair network. Given the fact that carriers of defective mutation and polymorphic variants of ataxia telangiectasia mutated are at higher risk of developing breast cancer, we hypothesized a role of the MRN genes in determining breast cancer susceptibility. This hypothesis was examined both in a case control study of 559 breast cancer patients and 1,125 healthy women of single-nucleotide polymorphisms in Mre11, Rad50, and Nbs1 and by the in vivo detection of binding between Mre11 and BRCA1, encoded by the breast cancer susceptibility gene BRCA1. We were also interested in defining whether any association between MRN genes and breast cancer was modified by reproductive risk factors reflecting the level of estrogen exposure or susceptibility to estrogen exposure, as estrogen is known to initiate breast cancer development due to its metabolites causing DSB formation. Support for the hypothesis came from the observations that (a) one single-nucleotide polymorphism in Nbs1 was significantly associated with breast cancer risk, and a trend toward an increased risk of developing breast cancer was found in women harboring a greater number of putative high-risk genotypes of MRN genes (an adjusted odds ratio of 1.25 for each additional putative high-risk genotype; 95% confidence interval, 1.10-1.44); (b) this association between risk and the number of putative high-risk genotypes was stronger and more significant in women thought to be more susceptible to estrogen, i.e., those with no history of full-term pregnancy, those older (>or=26 years of age) at first full-term pregnancy, or those having had fewer (<2) full-term pregnancies; the risk effect conferred by harboring a higher number of high-risk genotypes of MRN genes was more significant in women without a history of breast feeding; and (c) Mre11 and BRCA1 were shown to form a complex in vivo, and this interaction was increased by irradiation. This study supports the role of the MRN pathway in breast cancer development, further strengthening the suggestion that mechanisms regulating DSB repair may play a mutator role driving breast cancer pathogenesis.

Deletions and insertions within an amino-terminal domain of pp60v-src inactivate transformation and modulate membrane stability

We previously showed (V. W. Raymond and J. T. Parsons, Virology 160:400-410, 1987) that variants of the Prague A strain of Rous sarcoma virus containing large deletions impinging on a region of the src gene encoding amino acid residues 143 to 169 were defective for transformation of chicken cells in culture. Here we report that introduction of small (tri-and tetrapeptide) deletions into a region of pp60v-src containing amino acid residues 155 to 175 was found to inactivate transformation. In addition, insertion of four, but not one, amino acid residues at position 161 also inhibited transformation. Biochemical analysis of the src proteins encoded by individual transformation-defective variants revealed that the structural alterations introduced into this domain had only marginal effects upon src tyrosine-specific protein kinase activity. However, the src proteins encoded by defective variants exhibited a significantly shorter half-life within the cell, although these proteins efficiently and rapidly associated with cellular membranes. Our results suggest that the structural domain encompassing residues 155 to 177 may influence the stability of pp60src in the cellular membrane, possibly via the interaction of src with a cellular membrane component(s) or substrate(s).

Stable association of activated pp60src with two tyrosine-phosphorylated cellular proteins

We have identified two phosphotyrosine-containing cellular proteins with relative molecular masses of 130,000 (pp130) and 110,000 (pp110) daltons in chicken embryo cells that coimmunoprecipitated with pp60v-src and activated forms of chicken pp60c-src (pp60(527)F). Most if not all of the tyrosine-phosphorylated forms of pp130 and pp110 could be immunoprecipitated from lysates with any of several src protein-specific monoclonal antibodies directed against at least three spatially distinct epitopes. Consequently, of the more than 15 prominent phosphoproteins detected on immunoblots with phosphotyrosine-specific antibodies, pp130 and pp110 were selectively removed by src protein-specific immunoprecipitation, and their presence in the immunoprecipitates appears to have been due to a direct interaction with activated src proteins. src protein variants that induce different morphological phenotypes were altered in their ability to form detergent-stable complexes with pp130 and pp110 or with pp110 alone. Mutant src proteins, defective for myristylation, showed increased tyrosine phosphorylation of and association with pp110. Expression of src variants with mutations in the A box (pp60dl92/527F) or B box (pp60dl155/527F) of the src homology region induced differences in phosphorylation of pp130 and pp110, as well as changes in their association with variant src proteins. Sequences within the B-box region appeared to be necessary for stable complex formation with pp130 and pp110 and may be involved in the interaction of activated src proteins with cellular substrates.

Sonographic septation: a useful prognostic indicator of acute thoracic empyema

The aim of this study was to identify sonographic predictors of patient outcomes or need for surgical intervention of acute thoracic empyema. All patients with a clinical diagnosis of thoracic empyema underwent transthoracic ultrasonographic examination and thoracentesis at admission. According to the presence or absence of septa in sonographic images, the patients were classified into two groups: septated and nonseptated. Sonographic findings were analyzed with respect to duration of hospital stay, chest tube drainage, and treatment efficacy. A total of 163 consecutive patients were included in the study (83 patients with septated and 80 with nonseptated sonographic images). The mean duration of hospital stay (35.4 versus 27.0 days, P = 0.009) and chest tube drainage (13.1 versus 7.6 days, P < 0.001) for the patients with septa were significantly longer than for those without septa. The patients with septa were more likely to undergo intrapleural fibrinolytic therapy (63.8% versus 38.8%, odds ratio 2.79, P = 0.001) and surgical intervention (24.3% versus 7.5%, odds ratio 3.92, P = 0.004). We concluded that sonographic septation is a useful sign to predict the need for subsequent intrapleural fibrinolytic therapy and surgical intervention in cases of acute thoracic empyema. Early fibrinolytic therapy or even surgical intervention may be indicated in patients with sonographic septations.

Oxidative stress disrupts glucocorticoid hormone-dependent transcription of the amiloride-sensitive epithelial sodium channel alpha-subunit in lung epithelial cells through ERK-dependent and thioredoxin-sensitive pathways

The amiloride-sensitive epithelial Na(+) channel (ENaC) plays a critical role in the maintenance of alveolar fluid balance. It is generally accepted that reactive oxygen and nitrogen species can inhibit ENaC activity and aggravate acute lung injury; however, the molecular mechanism for free radical-mediated ENaC inhibition is unclear. Previously, we showed that the expression of the alpha-subunit of ENaC, alpha-ENaC, which is indispensable for ENaC activity, is repressed by Ras activation in salivary epithelial cells. Here, we investigated whether exogenous H(2)O(2) modulates alpha-ENaC gene expression in lung epithelial cells through a similar molecular mechanism. Utilizing transient transfection reporter assays and site-directed mutagenesis analyses, we found that the glucocorticoid response element (GRE), located at -1334 to -1306 base pairs of the alpha-ENaC 5'-flanking region, is the major enhancer for the stimulated alpha-ENaC expression in A549 lung epithelial cells. We further demonstrate that the presence of an intact GRE is necessary and sufficient for oxidants to repress alpha-ENaC expression. Consistent with our hypothesis, exogenous H(2)O(2)-mediated repression of alpha-ENaC GRE activity is partially blocked by either a specific inhibitor for extracellular signal-regulated kinase (ERK) pathway activation, U0126, or dominant negative ERK, suggesting that, in part, activated ERK may mediate the repressive effects of H(2)O(2) on alpha-ENaC expression. In addition, overexpression of thioredoxin restored glucocorticoid receptor action on the alpha-ENaC GRE in the presence of exogenous H(2)O(2). Taken together, we hypothesize that oxidative stress impairs Na(+) transport activity by inhibiting dexamethasone-dependent alpha-ENaC GRE activation via both ERK-dependent and thioredoxin-sensitive pathways. These results suggest a putative mechanism whereby cellular redox potentials modulate the glucocorticoid receptor/dexamethasone effect on alpha-ENaC expression in lung and other tight epithelia.

Prevalence and subtypes of dementia in a rural Chinese population

We conducted a single-stage community-based study of dementia on all registered residents > or =65 years in age in a rural Chinese community. Neurologists conducted semistructured interviews and examined all participants; they also interviewed family members in cases where dementia was suspected. The diagnosis was made by consensus according to the criteria of the Diagnostic and Statistical Manual of Mental Disorders, 3rd ed, revised (DSM-III-R). Among the 2,055 contacted individuals, 1,736 (84.5%) participated in the study and 44 ( 13 men and 31 women) were diagnosed as having dementia, including 35 (80%) with probable Alzheimer disease (AD) and 3 (7%) with vascular dementia (VsD). The rates of dementia were 0.5% for ages 65-74 years, 2.9% for ages 75-84 years, and 12.0% for ages 85-101 years. The overall rate was 2.5% for age > or =65 years. After controlling for age, neither a lack of formal education nor being a woman was a risk factor for dementia. At 2-year follow-up, 30 of the 44 demented participants had died, yielding a 2-year survival rate of 32%. The present results corroborated our previous findings of lower prevalence rates of dementia among the Chinese than among Western populations, and both genetic and sociocultural factors may have contributed to the low rates. The lack of neuroradiological imaging studies in the present study may have contributed to the finding of an unusually low rate of VsD.

Levodopa may improve orthostatic tremor: case report and trial of treatment

Primary orthostatic tremor is a regular fast lower limb tremor causing unsteadiness on standing. Treatment is generally unsatisfactory. A patient with primary orthostatic tremor who 9 years later developed levodopa responsive idiopathic Parkinson's disease is described. The patient exhibited the classic features of primary orthostatic tremor with relief of the tremor by walking or sitting while treated with levodopa. However, in the "off" state, when the benefits of levodopa disappeared, this orthostatic tremor was continuous and severely compromised the patient's gait. On the basis of this finding eight patients with primary orthostatic tremor were treated with levodopa. Five patients experienced benefit and elected to remain on long term treatment. This study is the first trial of therapy in primary orthostatic tremor and suggests that levodopa can lead to good symptomatic relief in this potentially disabling condition.

Activation of protein serine/threonine kinases p42, p63, and p87 in Rous sarcoma virus-transformed cells: signal transduction/transformation-dependent MBP kinases

We have used myelin basic protein immobilized in sodium dodecyl sulfate-polyacrylamide gels to identify protein kinases after gel electrophoresis, followed by protein kinase reactions. This technique has permitted us to detect three protein kinases in serum-deprived cells transformed by p60src. On induction of cellular transformation by a temperature-sensitive v-src, a p87 protein kinase is activated within 30 min and remains activated in fully transformed cells. The p63 protein kinase is not fully activated until 24 h but remains activated in transformed cells. The commonly studied p42MBPK is rapidly activated within 30 min, and its kinase activity decreases significantly by 24 h, when the p63 enzyme is fully activated. The p42MBPK, as well as the p63 and p87 enzymes, are stimulated by transforming p60c-src mutants but not normal c-src or nonmyristylated p60c-src. In addition, the kinase activity of p63 enzyme, but not of p42MBPK, can be induced in okadaic acid-treated chicken embryo fibroblasts, indicating that phosphatase 2A and/or phosphatase 1 may be involved in the regulation of its activity. Additional data indicate that either p42MBPK or p63 activity correlates with the stimulation of the protein kinase p90RSK. Thus, there may be two independent pathways leading to the activation of the RSK gene product.

Clinicopathologic analysis of malignant melanoma in Taiwan

BACKGROUND

Malignant melanoma is the leading cause of death among skin cancers in western countries. However, the incidence, histologic subtypes, and tumor behaviors are quite different in Asians and people of color.

OBJECTIVE

Our purpose was to define the tumor behaviors and possible prognostic predictors of melanomas based on a Taiwanese patient population.

METHODS

From the 65 patients diagnosed with melanoma at Veterans General Hospital, Taichung, we analyzed mean age at onset, gender, histologic subtypes, tumor thickness, level of invasion, primary tumor locations, and metastatic sites. Univariate analysis and multivariate analyses for survival, according to clinical and histologic tumor behaviors, were performed by means of Cox proportional hazard model. Survival curves were plotted by Kaplan-Meier method.

RESULTS

Fifty-one cutaneous melanomas were identified and analyzed by both clinical behaviors and histology. Acral lentiginous melanoma was the most common type (54.9%), followed by nodular melanoma (29.4%), superficial spreading melanoma, and lentigo maligna melanoma. Univariate analysis for overall survival of melanoma revealed that age at onset older than 55 years, male gender, ulceration of tumor, and thicker tumor have the tendency to poorer prognosis, but without significant differences. The advanced stages (III and IV) and histologic subtypes other than acral lentiginous melanoma predicted a poorer survival with significant differences. Multivariate analysis demonstrated advanced stages, and histologic subtypes were the independent risk factors for poor prognosis.

CONCLUSION

We proposed that histologic subtypes other than acral lentiginous melanoma and advanced stages have a poorer prognosis with significant differences.

Prevalence of headaches in a Chinese elderly population in Kinmen: age and gender effect and cross-cultural comparisons

OBJECTIVE

To investigate the prevalence of headaches in a Chinese elderly population.

BACKGROUND

There are few headache surveys in the elderly. Previous studies have shown a low headache prevalence in Chinese.

METHODS

TARGET POPULATION

eligible registered residents > or = 65 years old (N = 2,003) in two townships of Kinmen Island on August 1, 1993. All participants completed a headache questionnaire and underwent clinical evaluation and examination by a neurologist. Headache diagnoses were made according to the International Headache Society, 1988.

RESULTS

1,533 persons (77%) participated in the study, of whom 584 (38%) had at least one episode of headache in the previous year. One-year prevalence of migraine was 3.0%, and tension-type headache, 35%. The prevalence of migraine, but not tension-type headaches, continued to decline with age in the elderly. Life-time prevalence of "incapacitating headache" was 10%, and that of migraine, 5.2%. Forty-two percent of migraineurs stopped having migraine before this survey. In comparison with "10 years ago" 8% participants felt their current headaches were worse, 25% better, and 67%, no change, with a net improvement of 17%.

CONCLUSIONS

We have reported the highest headache prevalence among different Chinese elderly populations, but these were still lower than those reported from Western series. More than half of the elderly life-time migraineurs still had attacks of migraine. Severe headaches, including migraine but not tension-type headaches, declined with age.

A door-to-door survey of Parkinson's disease in a Chinese population in Kinmen

BACKGROUND

Most published studies have shown lower prevalence rates of Parkinson's disease (PD) in Asian and black African than in Western countries, leading to the hypothesis that Asians and blacks might be protected from PD.

OBJECTIVE

To investigate the prevalence of PD in a Chinese population.

DESIGN

Community-based survey.

SETTING

Registered residents 50 years of age or older (N = 5061) on the islet of Kinmen located off the southeastern coast of China [corrected].

METHOD

Single-phase door-to-door survey by neurologists. All participants were administered a questionnaire and received motor examinations of the Unified Parkinson's Disease Rating Scale.

RESULTS

The participation rate was 96% (N = 3915) among 4158 contacted individuals. Twenty-three cases of PD were identified, including three cases with dementia. The crude prevalence rate of PD was 587 (95% confidence interval (CI), 373 to 884) per 100,000 persons 50 years of age or older. Assuming no case of PD among individuals under 50 years of age, the prevalence rate was 119 (95% CI, 80 to 169) per 100,000 for the total population.

CONCLUSIONS

The prevalence rates of PD in Kinmen were much higher than those reported from mainland China, but slightly lower than those reported from more developed countries. The present findings suggest that, instead of genetic factors, differences in case-ascertainment, life expectancy, and the length of survival with PD may be more important contributors to the variations in observed PD prevalence rates.

Microscopic FTIR studies of lung cancer cells in pleural fluid

Structural changes associated with lung cancer and tuberculous cells in pleural fluid were studied by microscopic FTIR spectroscopy. Infrared spectra demonstrate significant spectral differences between normal, lung cancer and tuberculous cells. The ratio of the peak intensities of the 1030 and 1080 cm-1 bands (originated mainly in glycogen and phosphodiester groups of nucleic acids) differs greatly between normal and lung cancer samples. Such findings prompt the consideration that recording infrared spectra from lung cancer and tuberculous cells may be of diagnostic value. Since measurements of IR spectra of lung cancer cells in the pleural fluid can be a very rapid inexpensive process, our finding warrant exploration of this possibility in the investigation of the mechanism whereby the environmental pollution related cancers develop.