Mixed duct-acinar-islet cell tumor of the pancreas: report of a case

A 72-year-old Japanese woman presented at our hospital complaining of altered consciousness on arising every morning. The laboratory findings showed hypoglycemia and hyperinsulinemia. Abdominal ultrasonography revealed a tumor in the body of the pancreas. With a diagnosis of insulinoma, a surgical excision of the tumor was performed. A light microscopic examination and an immunohistochemical study revealed the tumor to consist of duct, acinar, and islet cell components. Mixed tumors of the pancreas are rare, and their clinical features and pathogenesis remain unclear. A further accumulation of clinical cases as well as a large number of histopathological studies on these rare mixed tumors is needed.

Organization of projections from the medial agranular cortex to the superior colliculus in the rat: a study using anterograde and retrograde tracing methods

The organization of corticotectal projections from the medial agranular cortex (AGm), which has been considered to contain rat's frontal eye field, was examined using anterograde and retrograde tracing techniques. When biotinylated dextranamine (BDA) injections were made into the rostral part of the AGm, small numbers of BDA-labeled axons were found in the rostral two-thirds of the superior colliculus (SC) while some labeled axons were seen in the caudal one-third of the SC. These labeled axons were distributed mainly in the lateral part of the stratum griseum intermediale. On the other hand, after BDA injections into the caudal part of the AGm, moderate to dense plexuses of labeled axons were found in the rostral two-thirds of the SC while some labeled axons were seen in the caudal one-third of the SC. These labeled axons were distributed in the ventromedial and dorsolateral marginal zones of the stratum griseum intermediale as well as in the stratum griseum profundum. The corticotectal projections were largely uncrossed. After combined injections of BDA into the caudal part of the AGm on one side and cholera toxin B subunit (CTb) into the paramedian pontine reticular formation on the opposite side or into the interstitial nucleus of Cajal on the same side, the overlapping distributions of BDA-labeled axons and CTb-labeled neurons were found in the ventromedial marginal zone of the stratum griseum intermediale ipsilateral to the site of BDA injection. These results suggest that the caudal part of the AGm plays a more significant role in the oculomotor function than does the rostral part of the AGm.

Expression of prolactin-releasing peptide in human placenta and decidua

The aims of this study were to determine whether the human placenta and decidua express PRL-releasing peptide (PrRP) mRNA and whether PrRP regulates PRL secretion from cultured human decidual cells. PrRP gene expression was analyzed by reverse transcription (RT)-PCR, and the level of the gene expression was quantified by a ribonuclease protection assay. PrRP gene expression was detected in both the placenta and decidua. These tissues expressed PrRP mRNA throughout pregnancy and the level of PrRP mRNA expression somewhat increased during midpregnancy. Placental and decidual cells also expressed PrRP mRNA, in vitro. To determine whether PrRP affects decidual PRL secretion, human endometrial stromal cells and decidual cells were cultured and treated with or without 1 microM PrRP31. PrRP31 did not affect PRL secretion in either short or long term incubation. Moreover, the RT-PCR analysis indicated that human decidua does not express the PrRP receptor, hGR3, mRNA. These findings suggest that PrRP produced by the human placenta and decidua does not affect decidual PRL secretion due to a lack of the receptor, and that it may play other roles during pregnancy.

Protein kinases required for segregation of vimentin filaments in mitotic process

Vimentin, one of type III intermediate filament (IF) proteins, is expressed not only in mesenchymal cells but also in most types of tumor cells. In the present study, we introduced several types of vimentin mutated at putative phosphorylation sites in its amino-terminal head domain into type III IF-negative T24 cells. Site-specific mutation induced the formation of an unusually long bridge-like IF structure between the unseparated daughter cells, although these mutants formed the filament network similar to wild type in interphase cells. Together with sites phosphorylated by Rho-kinase and protein kinase C (PKC), vimentin-Ser72, which can not be phosphorylated by any known vimentin kinase, was one of the mutation sites essential for this phenotype. We further demonstrated that vimentin-Ser72 was phosphorylated specifically at the cleavage furrow during cytokinesis. These observations suggest the existence of a novel protein kinase responsible for vimentin filament separation through the cleavage furrow-specific vimentin phosphorylation. We propose that Rho-kinase, PKC, and an unidentified vimentin-Ser72 kinase may play important roles in vimentin filament separation during cytokinesis.

Development of scales to measure dietary acculturation among Chinese-Americans and Chinese-Canadians

OBJECTIVE

To develop simple scales to measure a Chinese immigrant's adoption of Western eating patterns (dietary acculturation).

STUDY DESIGN AND PARTICIPANTS

Data are from 244 less-acculturated women of Chinese ethnicity living in Seattle, Wash, and Vancouver, British Columbia, Canada. Interviewers collected information on sociodemographic characteristics, acculturation indices, items that reflect Western and Chinese dietary behavior, and consumption of fruits, vegetables, and fat.

STATISTICAL ANALYSES

Analysis of variance and linear regression analyses examined associations among dietary measures and acculturation variables, controlling for age, education, and city of residence.

RESULTS

We developed 2 scales to assess dietary acculturation: the Western Dietary Acculturation Scale and the Chinese Dietary Acculturation Scale, measuring Western and Chinese eating behavior, respectively. Although the population in this study was a less-acculturated sample, most participants reported some Western dietary practices, such as drinking milk (78%), eating cheese (78%), eating at Western fast-food restaurants (56%), and eating between meals (72%). Younger, highly educated women employed outside the home had the highest Western dietary acculturation scores (P < .001). Women with high scores on the Western scale reported higher-fat dietary behaviors and had increased fruit and vegetable intake since immigration compared to those with lower scores (P < .001). There was good agreement between the dietary acculturation scales and traditional acculturation indicators (P < .001).

APPLICATIONS

Nutrition programs for immigrant/minority groups may be more effective if they are tailored to level of dietary acculturation. Therefore, the ability to accurately assess dietary acculturation is an important component of nutrition education, interventions, and counseling in these populations.

Second malignant neoplasms in five-year survivors of childhood cancer: childhood cancer survivor study

BACKGROUND

Because survival rates among childhood cancer patients are increasing, assessing the risk of second and subsequent malignant neoplasms (SMNs) is ever more important. Using the Childhood Cancer Survivor Study cohort, we identified the risk of SMNS:

METHODS

A retrospective cohort of 13 581 children diagnosed with common cancers before age 21 years and surviving at least 5 years was constructed with the use of data from patients treated at 25 U.S. and Canadian institutions. SMNs were ascertained through self-administered questionnaires and verified by pathology reports. Information on therapeutic exposures was abstracted from medical records. The risk of SMN was evaluated by standardized incidence ratios (SIRs) and excess absolute risk. Poisson multiple regression models were used to assess the impact of host and therapy factors on the risk of developing SMNS: All statistical tests were two-sided.

RESULTS

In 298 individuals, 314 SMNs were identified (SIR = 6.38; 95% confidence interval [CI] = 5.69 to 7.13). The largest observed excess SMNs were bone and breast cancers (SIR = 19.14 [95% CI = 12.72 to 27.67] and SIR = 16.18 [95% CI = 12.35 to 20.83], respectively). A statistically significant excess of SMNs followed all childhood cancers. In multivariate regression models adjusted for therapeutic radiation exposure, SMNs of any type were independently associated with female sex (P<.001), childhood cancer at a younger age (P for trend <.001), childhood Hodgkin's disease or soft-tissue sarcoma (P<.001 and P =.01, respectively), and exposure to alkylating agents (P for trend =.02). Twenty years after the childhood cancer diagnosis, the cumulative estimated SMN incidence was 3.2%. However, only 1.88 excess malignancies occurred per 1000 years of patient follow-up.

CONCLUSIONS

Success in treating children with cancer should not be overshadowed by the incidence of SMNS: However, patients and health-care providers must be aware of risk factors for SMNs so that surveillance is focused and early prevention strategies are implemented.

Breast cancer screening among Cambodian American women

Our aim was to describe and identify factors associated with breast cancer screening among Cambodian American women. We conducted a cross-sectional survey of 1,365 households using bilingual and bicultural interviewers. We found that low proportions of Cambodian American women were up to date on their clinical breast examinations (CBE; 42%) and mammograms (40%). More than 80% of women with female physicians have had at least one prior screening, and 52% have had the tests recently. Women with male Asian American physicians were less likely to have had screening as compared to women with female non-Asian physicians: ever had CBE (odds ratio [OR], 0.26); recent CBE (OR, 0.39); ever had mammogram (OR, 0.36); and recent mammogram (OR, 0.22). Breast cancer screening among Cambodian American women lags behind the general U.S. population. Tailored promotion efforts should address barriers and promote cancer screening by physicians, staff, and organizations serving this population.

Nine cases of granular cell tumors in B6C3F1 mice

The histological characteristics of 9 cases of granular cell tumors (GCTs) observed in B6C3F1 mice were examined to determine their cellular origin. Seven of the 9 cases were found in the uterus and other 2 cases were in the subcutaneous tissue. Tumor cells had abundant granules in the cytoplasm which were stained with PAS and were resistant to diastase treatment. Ultrastructurally, the granules were identified as lysosomes. The cell surface had cytoplasmic processus showing interdigitation with adjacent cells. A character feature of the tumor cells was the presence of a desmosome-like structure on their cell surface but no basal lamina was demonstrated. Although GCTs have been considered to be derived from Schwann cells on the basis of their ultrastructural features and S-100 protein-immunopositive findings, the absence of basal lamina in the present cases may raise a controversy as to their origin.

Comparisons of two breast cancer risk estimates in women with a family history of breast cancer

There is an increasing need for accurate prediction methods of assessing individual risk for breast cancer for both clinical and research purposes. The purpose of this study is to compare the Gail and Claus model risk estimates of breast cancer among women with a family history of breast cancer. This study presents risk estimates from two models of breast cancer risk in 491 women 18 to 74 years of age with a family history of breast cancer who were recruited to risk counseling clinical trials in Seattle, Washington between 1996 and 1997. These trials included women from the general population and additional samples of Ashkenazi Jewish, African-American, and lesbian women. We estimated and compared lifetime (to age 79) and 5-year risk for developing breast cancer using the National Surgical Adjuvant Breast and Bowel Project adaptation of the Gail model and the Claus model. About one-quarter of participants fell into the Gail "high" risk category (> or =1.7% risk of developing breast cancer in the next 5 years). The average lifetime risk was estimated at 13.2% by the Gail model and 11.2% by the Claus model. Estimates from the two models were moderately and positively correlated (r = 0.55) with the Gail model yielding a higher estimate than the Claus model for most participants. If women with a family history of breast cancer are being counseled regarding decisions on genetic testing, tamoxifen use, or other preventive measures, presenting both Claus and Gail estimates may be the best option.

Material deprivation and leading causes of death by gender: evidence from a nationwide small area study

STUDY OBJECTIVE

To investigate the association between material deprivation and 10 leading causes of death by gender.

DESIGN

Small area cross sectional ecological study using two dimensions of material deprivation (Index 1 and Index 2) drawn from 1991 census and cause specific mortality data aggregated for 1987-1995.

SETTING

2218 small areas in Spain.

MAIN RESULTS

Strong detrimental associations of two deprivation indices were found with top six leading causes of death for men and top seven leading causes of death for women, except breast cancer. For men, the highest percentages of excess mortality (between 40% and 60%) were found for smoking and alcohol related causes of death such as lung cancer, chronic obstructive pulmonary diseases, and cirrhosis while for women the highest percentages of excess mortality (between 40% and 60%) were found for diet related causes such as diabetes and ischaemic heart disease.

CONCLUSIONS

Health inequality is a widespread phenomenon in the majority of the top leading causes of deaths of the nation. Increasing levels of deprivation indices are associated with mortality risk differently by both cause and gender. Results suggest that deprivation effects mainly captured by Index 2 may manifest largely as unfavourable health behaviours leading to gender specific sets of causes of deaths. Findings of this study are consistent with the idea that material deprivation determines health inequality through both an increase of general susceptibility to ill health, leading to excess mortality in a wide range of causes, and a set of specific factors, resulting in an increased risk of death from a specific set of causes in each gender.

An increase in circulating mast cell colony-forming cells in asthma

We compared a potential to generate mast cells among various sources of CD34(+) peripheral blood (PB) cells in the presence of stem cell factor (SCF) with or without thrombopoietin (TPO), using a serum-deprived liquid culture system. From the time course of relative numbers of tryptase-positive and chymase-positive cells in the cultured cells grown by CD34(+) PB cells of nonasthmatic healthy individuals treated with G-CSF, TPO appears to potentiate the SCF-dependent growth of mast cells without influencing the differentiation into mast cell lineage. CD34(+) PB cells from asthmatic patients in a stable condition generated significantly more mast cells under stimulation with SCF alone or SCF+TPO at 6 wk of culture than did steady-state CD34(+) PB cells of normal controls. Single-cell culture studies showed a substantial difference in the number of SCF-responsive or SCF+TPO-responsive mast cell progenitors in CD34(+) PB cells between the two groups. In the presence of TPO, CD34(+) PB cells from asthmatic children could respond to a suboptimal concentration of SCF to a greater extent, compared with the values obtained by those of normal controls. Six-week cultured mast cells of asthmatic subjects had maturation properties (intracellular histamine content and tryptase/chymase enzymatic activities) similar to those derived from mobilized CD34(+) PB cells of nonasthmatic subjects. An increase in a potential of circulating hemopoietic progenitors to differentiate into mast cell lineage may contribute to the recruitment of mast cells toward sites of asthmatic mucosal inflammation.

Multi-beam polarized photometric detector for high-performance liquid chromatography

A novel multi-beam polarized photometric detector (PPD) for high-performance liquid chromatography (HPLC) is described. By pairing a polarizing prism with a thin quartz plate as a retarder, many linear polarized beams are produced at every 1/2 wavelength of the plate, and the polarizing axes of the adjacent beams intersect each other. The addition of another prism inclining its polarizing axis by pi/4 against the first one enables the simultaneous measurement of optical rotations based on the PPD at many wavelengths. The combination of these optics with a photo-diode array detector can be used to construct a modulated type polarimeter. This detector is designed to measure the optical rotation of an analyte at its absorption band. The spline function connecting the points at 1/4 wavelengths of the plate was used as a baseline to extract the PPD waves. The use of the similarity factor as a noise filter gave high sensitivity. Application of the proposed technique to an analyte carrying the Cotton absorption band provided good results.

Women's interest in genetic testing for breast cancer susceptibility may be based on unrealistic expectations

We report on results of an interview study assessing women's attitudes toward and hypothetical interest in genetic susceptibility testing for breast cancer. Data are from 246 interviews with women of varying ethnicity (African American, European American, Native American, and Ashkenazi Jewish), family history of breast cancer (negative, positive, and borderline), and educational level. Semistructured interviews included questions on general health beliefs; attitudes, experiences, and concerns about breast cancer; and hypothetical interest in genetic testing. Influence of specific test characteristics was assessed with 14 Likert scales varying negative and positive predictive value, timing of disease, possible medical interventions following a positive result. Results reported include both statistical and qualitative analysis. We found that women had a high level of interest in testing which, in general, did not vary by ethnicity, level of education, or family history. Interest in testing appeared to be shaped by an exaggerated sense of vulnerability to breast cancer, limited knowledge about genetic susceptibility testing, and generally positive views about information provided through medical screening. However, study participants were most interested in a test that didn't exist (high positive predictive value followed by effective, noninvasive, preventive therapy) and least interested in the test that does exist (less than certain positive predictive value, low negative predictive value, and limited, invasive, and objectionable therapeutic options). Our data suggest that without a careful counseling process, women could easily be motivated toward interest in a test which will not lead to the disease prevention they are seeking.

Extensive proliferation of oligodendrocyte precursors in the parenchyma of the embryonic chick central nervous system

The proliferation of oligodendrocyte lineage cells in the chick embryo central nervous system (CNS) was examined by double-immunolabeling with a lineage marker monoclonal antibody (mAb) O4 or mAb O1 and 5-bromo-3'-deoxyuridine (BrdU). In all regions examined, the first O4-positive (O4+) cells appeared in restricted regions of the ventricular zone (VZ), regarded as a site of oligodendrocyte origin. Within the O4+ focus, less than 20% of the O4+ cells incorporated BrdU. In contrast, O4+ cells in the parenchyma were mitotically active; for example, 40-50% of early O4+ cells were labeled with BrdU. Some of these were unipolar in shape, indicative of migratory precursor cells. The frequency of O4+/BrdU+ cell appearance decreased to less than 20% with further development. O1+ oligodendrocytes were largely mitotically inactive, with only approximately 5% of O1+ cells incorporating BrdU. These results clearly demonstrated that the VZ generates relatively few precursor cells and that these oligodendrocyte precursors actively generate their cohort in the parenchyma of the CNS.

Phrenic motoneurons receive monosynaptic inputs from the Kölliker-Fuse nucleus: a light- and electron-microscopic study in the rat

The parabrachial complex, which plays an important role in respiratory regulation, has been reported to send projection fibers to the phrenic nucleus, but the synaptic organization between the parabrachial fibers and the phrenic motoneurons has not been examined. Using anterograde and retrograde tracing methods, we found in the rat that the parabrachial fibers originating mainly from the Kölliker-Fuse nucleus (KF) terminated not only within the phrenic nucleus but also on the radial dendritic bundles of the phrenic motoneurons. It was further revealed that the KF fibers made asymmetrical synapses predominantly with dendrites and partly with somata of the phrenic motoneurons. These data suggest that output signals from the KF may exert excitatory influence directly upon the phrenic motoneurons.

Breast cancer risk and "delayed" primary Epstein-Barr virus infection

Parallel to its established causal association with both infectious mononucleosis (IM) and young adulthood Hodgkin disease (YAHD), we propose a hypothesis that "delayed" primary EBV infection (i.e., primary infection occurring during adolescence or adulthood) is associated with elevated breast cancer risk. We evaluated this hypothesis with two investigations, one descriptive and the other analytic. The descriptive study used international/United States cancer registry data to assess the association between incidence rates of breast cancer and those of YAHD. The incidence rates of the seemingly unrelated neoplasms were strongly correlated (correlation coefficients of 0.74 and 0.88 for international and United States data, respectively; these were higher than the correlation coefficients of YAHD with two other cancers that we considered). Populations with higher incidence rates corresponded to those with higher likelihood of delayed primary EBV infection. The analytical study was based on a population-based case-control study of breast cancer in middle-aged women. Age-adjusted odds ratios of breast cancer in women who reported a history of IM, relative to women who did not, increased monotonically from 0.55 [95% confidence interval (CI), 0.05-6.17] for women with 0-9 years of age at IM onset to 2.67 (CI, 1.04-6.89) for women with > or =25 years of age at IM onset (P = 0.016). An older age at tonsillectomy, another surrogate of delayed EBV exposure, was also associated with increased risk of breast cancer: odds ratios, 0.92 (CI, 0.57-1.48) and 1.76 (CI, 1.15-2.69) for women with tonsillectomy at 0-4 years of age and > or =15 years of age, respectively (P = 0.018). Adjusting for additional potential confounders did not modify the associations appreciably. The implications of the findings and a potential biological mechanism are presented.

An empirical evaluation of various priors in the empirical Bayes estimation of small area disease risks

Empirical and fully Bayes estimation of small area disease risks places a prior distribution on area-specific risks. Several forms of priors have been used for this purpose including gamma, log-normal and non-parametric priors. Spatial correlation among area-specific risks can be incorporated in log-normal priors using Gaussian Markov random fields or other models of spatial dependence. However, the criterion for choosing one prior over others has been mostly logical reasoning. In this paper, we evaluate empirically the various priors used in the empirical Bayes estimation of small area disease risks. We utilize a Spanish mortality data set of a 12-year period to give the underlying true risks, and estimate the true risks using only a 3-year portion of the data set. Empirical Bayes estimates are shown to have substantially smaller mean squared errors than Poisson likelihood-based estimates. However, relative performances of various priors differ across a variety of mortality outcomes considered. In general, the non-parametric prior provides good estimates for lower-risk areas, while spatial priors provide good estimates for higher-risk areas. Ad hoc composite estimates averaging the estimates from the non-parametric prior and those from a spatial log-normal prior appear to perform well overall. This suggests that an empirical Bayes prior that strikes a balance between these two priors, if one can construct such a prior, may prove to be useful for the estimation of small area disease risks.

Analysis of muscle proteins in acute quadriplegic myopathy

We investigated the changes of muscle proteins in acute quadriplegic myopathy (AQM) using immunohistochemistry and stoichiometry. Cases of AQM were observed in which it was difficult to type muscle fibers with adenosine triphosphatase staining in biopsied muscle. Well-defined typing of these cases was possible by performing immunofluorescent staining using slow and fast skeletal troponin I (TnI) antibodies. By this means, small angular fibers were shown to be fast skeletal muscle, and myosin was absent from these muscle fibers. Actin and tropomyosin were maintained. Muscle protein ratios were determined by stoichiometry following sodium dodecyl sulfate-polyacrylamide gel electrophoresis of AQM myofibril specimens from four subjects. The myosin heavy chain/actin ratio was significantly decreased compared with a normal control group and other neuromuscular diseases. These pathologic findings returned to normal during recovery from AQM. Thus, myosin selectively decreases, whereas actin and regulatory proteins located above it are maintained during AQM.

Morphological evidence for a vestibulo-thalamo-striatal pathway via the parafascicular nucleus in the rat

We observed by anterograde and retrograde tracing techniques that projection fibers originating from the medial vestibular nucleus (MVe) of the rat terminated in the dorsal two-thirds of the lateral part of the parafascicular thalamic nucleus (PF), where neurons sending their axons to the dorsolateral part of the striatum existed. It was further revealed that the vestibular fibers made asymmetrical synaptic contacts mainly with dendrites and additionally with soma of the striatum-projecting PF neurons. These data suggest that output signals from the MVe may be transmitted disynaptically to the striatal neurons via the PF neurons.

Cerebrosides in grapevine leaves: distinct composition of sphingoid bases among the grapevine species having different tolerances to freezing temperature

Cerebrosides from leaves of three grapevine species were analyzed in detail. The relative proportions of 8-E/Z isomers of 4-hydroxy-8-sphingenines [i.e. 8-E/Z t18:1(8E) and (8Z)] differed amongst the species in respect to freezing tolerance. This suggests that the occurrence of high levels of t18:1(8Z) in cerebrosides is correlated with freezing tolerance in these species.

Predicting functional status outcomes in hospitalized patients aged 80 years and older

OBJECTIVE

To develop a model estimating the probability of a patient aged 80 years or older having functional limitations 2 months and 12 months after being hospitalized.

DESIGN

A prospective cohort study.

SETTING

Four teaching hospitals in the US.

PARTICIPANTS

Enrolled patients were nonelective hospital admissions aged 80 years or older who stayed in hospital at least 48 hours. The 804 patients who survived and completed an interview at 2 months and the 450 who completed an interview at 12 months were from the 1266 patients in the Hospitalized Elderly Longitudinal Project (HELP) (76% and 47% of survivors, respectively). Median age of the 2-month survivors was 84.7 years.

MEASUREMENTS AND MAIN OUTCOMES

Patient function 2 and 12 months after enrollment was defined by the number of dependencies in Activities of Daily Living (ADLs). Ordinal logistic regression models were constructed to predict functional status. Predictors included demographic characteristics, disease category, geriatric conditions, severity of physiologic imbalance, current quality of life, and exercise capacity and ADLs 2 weeks before study admission.

RESULTS

Before admission, 39% of patients were functionally independent in ADLs. Of patients who survived and were interviewed at 2 months, 32% were functionally independent, and at 12 months, 36% were independent. Among patients with no baseline dependencies, 42% had developed one or more limitations 2 months later, and 41 % had limitations 12 months later. The patient's ability to perform activities of daily living at baseline was the most important predictor of functional status at both 2 and 12 months. In a multivariable predictive model, independent predictors of poorer functional status at 2 months included: worse baseline functional status and quality of life; depth of coma, if any; lower serum albumin level; presence of dementia, depression, or incontinence; being bedridden; medical record documentation of need for nursing home; and older age. Model performance, assessed using Somers' D, was 0.61 for 2 months and 0.57 for 12 months (Receiver Operating Characteristic (ROC) area = 0.81 and .79, respectively.) Bootstrap validation of the month 2 model also yielded a Somers' D = 0.60. The models were well calibrated over the entire risk range. The ROC area for prediction of the loss of independence was 0.76 for 2 months and 0.68 for 12 months.

CONCLUSIONS

Many older patients are functionally impaired at the time of hospitalization, and many develop new functional limitations. A limited amount of readily available clinical information can yield satisfactory predictions of functional status 2 months after hospitalization. Models like this may prove to be useful in clinical care. This work illuminates a potential method for risk adjustment in research studies and for monitoring quality of care.

Topographical organization of projections from the subiculum to the hypothalamus in the rat

The projections from the subiculum to the hypothalamus were comprehensively examined in the rat by using the anterograde Phaseolus vulgaris leucoagglutinin (PHA-L) and retrograde cholera toxin B subunit (CTb) methods. Tracing of efferents with PHA-L indicated that the medial preoptic region received projection fibers from the temporal two-thirds of the subiculum, whereas the anterior, tuberal, and mammillary regions received those from the full longitudinal extent of the subiculum. The subicular projections to the anterior and tuberal hypothalamic regions were also found to be organized in a topographical manner such that the temporal-to-septal axis of origin in the subiculum determined a ventromedial-to-dorsolateral axis of termination in the medial zone of the hypothalamus: Massive labeled fibers from the temporalmost part of the subiculum terminated in the subparaventricular zone and its caudal continuum around the dorsal and medial aspects of the ventromedial nucleus, and those from progressively more septal parts terminated in progressively more dorsolateral parts of the medial zone. In addition, the temporal-to-septal axis of origin in the subiculum tended to determine a medial-to-lateral axis of termination in the preoptic region as well as a ventral-to-dorsal axis of termination in the mammillary region. Furthermore, the temporal-to-septal axis of origin in the septal two-thirds of the subiculum corresponded to a ventrolateral-to-dorsomedial axis of termination in the medial mammillary nucleus. The topographical projections from the subiculum to the medial zone of the hypothalamus were confirmed by CTb experiments, representatively in the subicular projections to the anterior hypothalamic region. These results suggest that different populations of neurons existing along the longitudinal axis of the subiculum may exert their influences on the execution of different hypothalamic functions.

Lack of association between the C677T MTHFR polymorphism and colorectal hyperplastic polyps

Colorectal hyperplastic polyps are benign lesions that share many risk factors with colorectal adenomas and cancers. Low folate intakes are associated with an increased risk of colon cancer. The enzyme 5,10-methylene-tetrahydrofolate reductase (MTHFR) may be linked to DNA methylation and nucleotide synthesis and thus play a role in the etiology of colorectal neoplasia. We investigated an association between the common MTHFR polymorphism (C677T) and colorectal hyperplastic polyps within the Minnesota Cancer Prevention Research Unit case-control study. Cases (n = 200) were diagnosed with colonoscopically confirmed hyperplastic polyps; controls (n = 645) were derived from the same gastroenterology practice and were polyp-free at colonoscopy. Dietary intakes were estimated from a self-administered food-frequency questionnaire prior to colonoscopy. Multivariate adjusted odds ratios (ORs) and 95% confidence intervals for MTHFR status were 0.8 (0.6-1.2; CT versus CC wild-type) and 0.9 (0.5-1.6; TT versus CC). In subgroup analyses stratified on dietary intakes of folate, vitamin B12, vitamin B6, or methionine, those with the TT genotype and either low intakes of folate or vitamin B6 were at increased risk relative to those with normal or high vitamin intake. However, most 95% confidence intervals included 1.0, and no consistent trends were observed. In contrast to our findings on colorectal adenomas, increasing alcohol consumption was associated with an elevated risk of colorectal hyperplastic polyps, regardless of genotype. The MTHFR (C677T) variant genotype does not appear to be related to risk of colorectal hyperplastic polyps, and there is no convincing evidence that MTHFR shows a different relation to risk, dependent on dietary intakes of nutrients related to its pathway.