Publications by authors named "Weitkamp L"

Interspecific competition can significantly impact marine ecosystems by affecting species distributions and abundances. Understanding how sympatric species utilize available food helps identify potential competition and its effects when resources are limited. Here, we applied a suite of analytical methods (diet analysis, stable isotopes, and biomass estimates) to identify potential competitive interactions among North Pacific pelagic predators.

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Background: Status epilepticus (SE) is a neurologic emergency defined as continued seizure activity greater than five minutes or recurrent seizure activity without return to baseline. Benzodiazepine-refractory SE is continuous seizure activity despite treatment with a benzodiazepine. Treatment of benzodiazepine-refractory SE includes levetiracetam with loading doses ranging from 20 mg/kg to 60 mg/kg up to a maximum dose of 4500 mg.

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Major ecological realignments are already occurring in response to climate change. To be successful, conservation strategies now need to account for geographical patterns in traits sensitive to climate change, as well as climate threats to species-level diversity. As part of an effort to provide such information, we conducted a climate vulnerability assessment that included all anadromous Pacific salmon and steelhead (Oncorhynchus spp.

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Although it is often assumed that valence processing in the prefrontal cortex (PFC) is similar for stimuli originating from different sensory modalities, evidence supporting this view is lacking. To address this, we recruited 20 male participants and used a delayed-response fMRI design to test whether perceived pleasantness of flavors and images is similarly processed in the PFC. As predicted, significant correlations were observed between image and flavor pleasantness ratings, and PFC response to these stimuli; however, these responses were spatially different, with flavor pleasantness reflected in more ventrally located PFC regions than image pleasantness.

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The ventral emotion network-encompassing the amygdala, insula, ventral striatum, and ventral regions of the prefrontal cortex-has been associated with the identification of emotional significance of perceived external stimuli and the production of affective states. Functional magnetic resonance imaging (fMRI) studies investigating chemosensory stimuli have associated parts of this network with pleasantness coding. In the current study, we independently analyzed two datasets in which we measured brain responses to flavor stimuli in young adult men.

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Widespread population extirpations and the consequent loss of ecological, genetic, and life-history diversity can lead to extinction of evolutionarily significant units (ESUs) and species. We attempted to systematically enumerate extinct Pacific salmon populations and characterize lost ecological, life history, and genetic diversity types among six species of Pacific salmon (Chinook [Oncorhynchus tshawytscha], sockeye [O. nerka], coho [O.

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Background: Family studies have demonstrated that the autism spectrum disorders (ASDs) have a major genetic etiologic component, but expression and penetrance of the phenotype are variable. Mice with null mutations of Hoxa1 or Hoxb1, two genes critical to hindbrain development, have phenotypic features frequently observed in autism, but no naturally occurring variants of either gene have been identified in mammals.

Methods: By sequencing regions of genomic DNA of patients with autism spectrum disorders, we detected a substitution variant at HOXA1 and an insertion variant at HOXB1, both in coding regions of the genes.

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Testing for random mating in human populations is difficult due to confounding factors such as ethnic preference and population stratification. With HLA, the high level of polymorphism is an additional problem since it is rare for couples to share the same haplotype. Focus on an ethnically homogeneous population, where levels of polymorphism at HLA loci are more limited, may provide the best situation in which to detect non-random mating.

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Prior studies in the Schmiedeleut Hutterites of South Dakota have demonstrated associations between human leukocyte antigen (HLA) haplotype matching and fetal loss (Ober et al. 1992) and mate preferences (Ober et al. 1997), as well as deficiencies of homozygotes for HLA haplotypes (Kostyu et al.

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The role that maternal and fetal human leukocyte antigen (HLA) genes play in pregnancy is unknown, but it has been suggested that fetuses whose HLA alleles do not differ from maternal alleles (i.e. histocompatible fetuses) are more likely to be aborted than fetuses with HLA alleles that differ from maternal alleles (i.

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Evidence from studies in rodents suggests that mate selection is influenced by major-histocompatibility-complex haplotypes, with preferences for dissimilar partners. This study was initiated to determine whether avoidance of a mate with the same HLA haplotype as one's own might be occurring in the Hutterites, a North American reproductive isolate of European ancestry, notable for their large sibships, communal lifestyle, and limited number of five-locus HLA haplotypes (HLA-A, -B, -C, -DR, and -DQ). HLA haplotypes were known for 411 Hutterite couples.

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A study of 49 pairs of monozygous (MZ) twins and 38 pairs of same-sexed dizygous (DZ) twins showed that lean body mass (LBM), as determined by potassium 40 counting, is under genetic influence. Intrapair variances for LBM are much smaller than those for body fat, which suggests that LBM has a higher degree of heritability. There is a correlation between the magnitude of intrapair LBM differences and intrapair weight differences for both sets of twins, showing that environment is also an important influence.

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The long-QT (LQT) syndrome is a genetically complex disorder that is characterized by syncope and fatal ventricular arrhythmias. LQT syndrome, as defined by a prolonged electrocardiographic QT interval, has a higher incidence in females than in males and does not exhibit Mendelian transmission patterns in all families. Among those families that are nearly consistent with Mendelian transmission, linkage between a locus for LQT syndrome and the H-ras-1 locus on the short arm of chromosome 11 has been reported in some families but not in others.

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We report nine additional cases of new-onset multiple sclerosis (MS) among employees of an upstate New York manufacturing plant that uses zinc as a primary metal. These cases, identified during the decade 1980 to 1989, had clinical onset of the disease between 1979 and 1987. The new cases confirm the increased incidence of MS previously reported in the plant population for the 1970 to 1979 decade.

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Four allelic forms of serum plasminogen (PLG) were detected in baboons (Papio hamadryas Linneaus 1758) by isoelectric focusing and were determined to be inherited as autosomal codominant traits. Linkage analysis of data from 179 progeny and their parents revealed that PLG is tightly linked (lod score = 30.20) to the gene encoding apolipoprotein(a) (LPA), as in humans.

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Background: The Long QT Syndrome (LQTS) is an infrequently occurring familial disorder in which affected individuals have electrocardiographic QT interval prolongation and a propensity to ventricular tachyarrhythmic syncope and sudden death. We prospectively investigated the clinical characteristics and the long-term course of 3,343 individuals from 328 families in which one or more members were identified as affected with LQTS (QTc greater than 0.44 sec1/2).

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Histological features of the endometrium, as assessed in biopsy samples, were related to Standardbred mare genotypes for transferrin, esterase (as a control) and equine leucocyte antigens (ELA). Pathological changes were found more frequently in each successively older age group of mares. Among mares aged 6-19 years, there were significant pathologic changes on first examination following an infertile breeding season for 46 of 90 (51%) of transferrin homozygotes and 50 of 146 (34%) of transferrin heterozygotes.

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Analysis of HLA haplotype distributions in relation to major affective disorder in affected sibling pairs and affected aunt or uncle and niece or nephew pairs confirmed that HLA-region genes do contribute to susceptibility to affective disorder. The data indicated that this effect may be greater in unipolar than in bipolar disorder, and more apparent in families with few affected members than in heavily loaded families. Nonrandom assortment of HLA haplotypes to affected and unaffected offspring in "low load" families occurred principally for the haplotype transmitted from the side of the family without affective disorder.

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The Toronto-Rochester Depression study consisted of 116 pedigrees ascertained for multiple cases of major affective disorders. Among the 857 psychiatrically evaluated family members, of whom more than 85% were given a structured interview, 363 had major affective disorder by Research Diagnostic Criteria and 385 had no history of psychological aberration. HLA region genes were typed in 804 of these persons.

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To investigate a possible genetic cause underlying the clinical association between multiple sclerosis (MS) and affective disorder, we studied 56 patients with MS for psychiatric and genetic (family history, sex, and HLA-DR) characteristics. The 2:1 ratio of females to males expected for patients with MS was observed in this sample (40:16), but the excess of females occurred entirely among the 31 MS patients with major affective disorder (27 females and four males). Bipolar probands with MS had significantly more relatives with affective disorder or MS than did unipolar probands with MS.

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HLA typing was conducted on 577 family members of 86 families having at least two first-degree family members with a lifetime history of major depression or bipolar disorder. The results were combined with a follow-up study of 10 Newfoundland kindreds and with the data obtained from our previous studies, giving a total cohort of 117 families of diverse ethnic and geographic origin. There was increased sharing of HLA haplotypes, as compared with random expectation, over all possible pairwise comparisons both in the follow-up studies (P less than 0.

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A locus, LP, that determines quantitative variation of Lp(a) lipoprotein phenotypes is linked to the plasminogen (PLG) locus (peak lod score = 12.73). This linkage relationship assigns a locus with alleles that have an affect on risk for coronary artery disease to the long arm of chromosome 6.

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