Epidemiological studies show that obesity has deleterious effects on the brain and cognitive function in the elderly population. However, the specific mechanisms through which aging and obesity interact to promote cognitive decline remain unclear. To test the hypothesis that aging exacerbates obesity-induced cerebromicrovascular impairment, we compared young (7 months) and aged (24 months) high-fat diet-fed obese C57BL/6 mice. We found that aging exacerbates the obesity-induced decline in microvascular density both in the hippocampus and in the cortex. The extent of hippocampal microvascular rarefaction and the extent of impairment of hippocampal-dependent cognitive function positively correlate. Aging exacerbates obesity-induced loss of pericyte coverage on cerebral microvessels and alters hippocampal angiogenic gene expression signature, which likely contributes to microvascular rarefaction. Aging also exacerbates obesity-induced oxidative stress and induction of NADPH oxidase and impairs cerebral blood flow responses to whisker stimulation. Collectively, obesity exerts deleterious cerebrovascular effects in aged mice, promoting cerebromicrovascular rarefaction and neurovascular uncoupling. The morphological and functional impairment of the cerebral microvasculature in association with increased blood-brain barrier disruption and neuroinflammation (Tucsek Z, Toth P, Sosnowsk D, et al. Obesity in aging exacerbates blood-brain barrier disruption, neuroinflammation and oxidative stress in the mouse hippocampus: effects on expression of genes involved in beta-amyloid generation and Alzheimer's disease. J Gerontol Biol Med Sci. 2013. In press, PMID: 24269929) likely contribute to obesity-induced cognitive decline in aging.

BACKGROUND

One-fifth of patients with seemingly 'curable' pancreatic ductal adenocarcinoma (PDA) experience an early recurrence and death, receiving no definable benefit from a major operation. Some patients with advanced stage tumors are deemed 'unresectable' by conventional staging criteria (e.g. liver metastasis), yet progress slowly. Effective biomarkers that stratify PDA based on biologic behavior are needed. To help researchers sort through the maze of biomarker data, a compendium of ∼2500 published candidate biomarkers in PDA was compiled (PLoS Med, 2009. 6(4) p. e1000046).

RESULTS

Building on this compendium, we constructed a survival tissue microarray (termed s-TMA) comprised of short-term (cancer-specific death <12 months, n = 58) and long-term survivors (>30 months, n = 79) who underwent resection for PDA (total, n = 137). The s-TMA functions as a biological filter to identify bona fide prognostic markers associated with survival group extremes (at least 18 months separate survival groups). Based on a stringent selection process, 13 putative PDA biomarkers were identified from the public biomarker repository. Candidates were tested against the s-TMA by immunohistochemistry to identify the best markers of tumor biology. In a multivariate model, MUC1 (odds ratio, OR = 28.95, 3+ vs. negative expression, p = 0.004) and MSLN (OR = 12.47, 3+ vs. negative expression, p = 0.01) were highly predictive of early cancer-specific death. By comparison, pathologic factors (size, lymph node metastases, resection margin status, and grade) had ORs below three, and none reached statistical significance. ROC curves were used to compare the four pathologic prognostic features (ROC area = 0.70) to three univariate molecular predictors (MUC1, MSLN, MUC2) of survival group (ROC area = 0.80, p = 0.07).

CONCLUSIONS

MUC1 and MSLN were superior to pathologic features and other putative biomarkers as predicting survival group. Molecular assays comparing cancers from short and long survivors are an effective strategy to screen biomarkers and prioritize candidate cancer genes for diagnostic and therapeutic studies.

A recent article by Montecino-Rodriguez et al. [Montecino-Rodriguez, E., Leathers, H. & Dorshkind, K. (2006) Nat. Immunol.7, 293-301] has distinguished the early progenitors for B-1 cells, which principally develop in neonates, from early progenitors for B-2 cells, which principally develop in adult bone marrow. Here we introduce syndecan-1 (CD138) and MHC class II (I-A) as markers of early B cell development [Hardy, R. R., Carmack, C. E., Shinton, S. A., Kemp, J. D. & Hayakawa, K. (1991) J. Exp. Med. 173, 1213-1225; Hardy fractions B-D] and show that the expression of these markers distinguishes the predominant B cell development pathway in neonates from the corresponding predominant pathway in adults (both progenitors are present but differently represented in each case). We show that pre-B cells (Hardy fraction D) in the predominant adult pathway express high levels of CD138 and intermediate levels of I-A, whereas the corresponding pre-B cells in the pathway that predominates in neonates do not express either of these markers. As expected, because most of the pre-B cells in adults express CD138, we find that sorted CD138+ adult pre-B cells differentiate to IgM+ B cells in vitro. Sorted CD138- pre-B cells from neonates, the majority subset at this age, also mature to IgM+ cells (without passing through a CD138+ stage). Importantly, our studies here confirm the differential representation of adult and neonatal progenitor populations and further demonstrate that CD138 expression subdivides the adult CD19+, B220-6B2-/low population shown to contain B-1 progenitors in a way consistent with the predominance of B-1b progenitors in adults. Thus, CD138 expression provides a key route to distinguishing early B cell development pathway for what now are clearly three B cell lineages.

Calculations of the radiofrequency magnetic (B(1)) field, SAR, and SNR as functions of frequency between 64 and 345 MHz for a surface coil against an anatomically-accurate human chest are presented. Calculated B(1) field distributions are in good agreement with previously-published experimental results up to 175 MHz, especially considering the dependence of field behavior on subject anatomy. Calculated SNR in the heart agrees well with theory for low frequencies (nearly linear increase with B(0) field strength). Above 175 MHz, the trend in SNR with frequency begins to depend largely on location in the heart. At all frequencies, present limits on local (1 g) SAR levels are exceeded before limits on whole-body average limits. At frequencies above 175 MHz, limits on SAR begin to be an issue in some common imaging sequences. These results are relevant for coils and subjects similar to those modeled here. Magn Reson Med 45:692-699, 2001.

The ubiquitous herpesvirus Epstein-Barr virus (EBV) is linked to the development of several malignancies, including nasopharyngeal carcinoma. Latent membrane protein 1 (LMP1) is considered the EBV oncogene as it is necessary for EBV-induced transformation of B lymphocytes and is able to transform Rat-1 fibroblasts. LMP1 can activate a wide array of signaling pathways, including phosphatidylinositol 3-kinase (PI3K)-Akt and NF-kappaB. Six sequence variants of LMP1, termed Alaskan, China 1, China 2, Med+, Med-, and NC, have been identified, and individuals can be infected with multiple variants. The frequencies of detection of these variants differ for various EBV-associated malignancies from different geographic regions. In this study, the biological and signaling properties of the LMP1 variants have been characterized. All of the LMP1 variants transformed Rat-1 fibroblasts, induced increased motility of HFK cells, and induced increased homotypic adhesion of BJAB cells. While all the variants activated the PI3K-Akt signaling pathway to similar extents, the Alaskan, China 1, and Med+ variants had limited binding to the E3 ubiquitin ligase component homologue of Slimb and had slightly enhanced NF-kappaB signaling. These findings indicate that the signature amino acid changes of the LMP1 variants do not hinder or enhance their in vitro transforming potentials or affect their signaling properties.

We recently reported a significant relationship between lung function measured prior to any lower respiratory tract illness and subsequent wheezing illnesses during the first year of life (N Engl J Med 1988; 319:1112-7). Follow-up has continued for this group of infants during the second and third years of life. When compared with never wheezers, infants who wheezed during the first year of life and had at least one additional lower respiratory illness had 22% lower initial levels of an indirect index of airway conductance derived from the shape of tidal breathing curves (p less than or equal to 0.01), 22% lower respiratory conductance (p less than or equal to 0.05), 25% lower maximal flows at the end-expiratory point (p less than or equal to 0.01), and 10% lower functional residual capacity (p less than or equal to 0.05). Infants who wheezed only once during the first 3 yr of life or who started wheezing during the second year of life had normal tidal breathing curves but significantly lower maximal expiratory flows (p less than or equal to 0.05). Their functional residual capacity was also lower than that of never wheezers (p less than or equal to 0.05). We conclude that diminished initial airway function may be a predisposing factor for recurrent wheezing respiratory illnesses starting in the first year of life. Infants who will have only one wheezing respiratory illness or who will start wheezing after the first year of life seem to have lower levels for some but not for all lung function tests performed in this study.

Optic pathway gliomas and brainstem gliomas are the predominant intracranial neoplasms associated with neurofibromatosis type 1 (NF1). Before the past 15 years, studies of optic pathway gliomas in NF1 were hampered by the inaccurate diagnosis of NF1, the unavailability of noninvasive neuroimaging techniques, and the frequent rendering of what would now be considered unnecessary, overly aggressive therapy. When studied systematically, these tumors behave in a much more benign fashion than their counterparts in children who do not have NF1. While they may cause symptoms in as many of 50% of cases, progression to the point where specific intervention is deemed necessary is unusual. Consequently, screening neuroimaging of asymptomatic patients is unwarranted. Because optic pathway tumors universally arise in children younger than 7 years of age, all such children should undergo yearly ophthalmologic evaluations and annual assessments of growth to monitor for signs of precocious puberty. Am. J. Med. Genet. (Semin. Med. Genet.) 89:38-44, 1999.

This year the most prestigious prize in medical sciences, the Lasker Award, has been presented to the three scientists who discovered the ubiquitin pathway: Aaron Ciechanover, Avram Hershko, and Alexander Varshavsky [Nature Med. 6 (2000) 1073-1081]. During a time when the scientific community was focused on understanding how proteins were synthesized, they intently pursued the novel idea that cells were programmed to selectively destroy proteins. Their work led to the identification of an elaborate system of protein degradation targeting a myriad of cellular substrates. A small protein called ubiquitin is at the center of this process. Although the ubiquitin pathway was first described in the early 1980s, it has only more recently advanced to the forefront of basic research as a significant regulatory network within the cell. The field continues to grow as new ubiquitination enzymes and novel functions of this system are identified. Scientists are focused on elucidating the mechanisms by which cells deploy the ubiquitin pathway to control levels of selected proteins, such as cell cycle regulatory proteins, transcription factors and signaling molecules. Accelerated or decelerated rates of degradation of particular substrates participate in the genesis of many human diseases. Thus, understanding the mechanisms that confer specificity to the ubiquitin system will allow the development of novel therapeutic approaches to target aberrations in this pathway underlying tumorigenesis and other human pathologies.

HIV-1 infection is characterized by a progressive decline in CD4(+) T cells leading to a state of profound immunodeficiency. IL-2 therapy has been shown to improve CD4(+) counts beyond that observed with antiretroviral therapy. Recent phase III trials revealed that despite a sustained increase in CD4(+) counts, IL-2-treated patients did not experience a better clinical outcome [Abrams D, et al. (2009) N Engl J Med 361(16):1548-1559]. To explain these disappointing results, we have studied phenotypic, functional, and molecular characteristics of CD4(+) T cell populations in IL-2-treated patients. We found that the principal effect of long-term IL-2 therapy was the expansion of two distinct CD4(+)CD25(+) T cell populations (CD4(+)CD25(lo)CD127(lo)FOXP3(+) and CD4(+)CD25(hi)CD127(lo)FOXP3(hi)) that shared phenotypic markers of Treg but could be distinguished by the levels of CD25 and FOXP3 expression. IL-2-expanded CD4(+)CD25(+) T cells suppressed proliferation of effector cells in vitro and had gene expression profiles similar to those of natural regulatory CD4(+)CD25(hi)FOXP3(+) T cells (Treg) from healthy donors, an immunosuppressive T cell subset critically important for the maintenance of self-tolerance. We propose that the sustained increase of the peripheral Treg pool in IL-2-treated HIV patients may account for the unexpected clinical observation that patients with the greatest expansion of CD4(+) T cells had a higher relative risk of clinical progression to AIDS.

BACKGROUND

This study was undertaken to estimate the most recent prevalence of cigarette smoking by occupation and industry in the US, using the data from the third National Health and Nutrition Examination Survey (NHANES III), 1988-1994.

METHODS

Included in NHANES III are data on the cigarette smoking status, occupation, industry, and other demographic information of US non-institutionalized civilians obtained through household interview surveys. The study population included 20,032 adults aged 17 years and older. To estimate the prevalence of cigarette smoking across occupation and industry groups, we used the Survey Data Analysis (SUDAAN) software.

RESULTS

The prevalence of cigarette smoking was highest among material moving occupations, construction laborers, and vehicle mechanics and repairers. The lowest smoking prevalence was found among teachers. Among industry groups, the construction industry had the highest prevalence of cigarette smoking.

CONCLUSIONS

These findings provide information useful for targeting education activities focusing on adverse health effects of cigarette smoking and also for indirect adjustments in analysis of morbidity and mortality by occupation. Am. J. Ind. Med. 40:233-239, 2001. Published 2001 Wiley-Liss, Inc.

Improvements on a localized, automatic shimming method described by Gruetter and Boesch (J. Magn. Reson. 96, 323-334 (1992)) and Gruetter (Magn. Reson. Med. 29, 804-811 (1993)) are presented. A spin-echo sequence employing a double sech refocusing scheme is used to acquire a field map along linear projections that improves the signal-to-noise ratio by at least a factor of two over the stimulated echo sequence previously used. To further improve the reliability of shim adjustments, a variance-weighted polynomial regression analysis is performed. This also extends the scope of application of this technique to global shimming. Localized 1H spectra of human brain shimmed by this method are presented.

Serum amyloid A isoforms, apoSAA1 and apoSAA2, are apolipoproteins of unknown function that become major components of high density lipoprotein (HDL) during the acute phase of an inflammatory response. ApoSAA is also the precursor of inflammation-associated amyloid, and there is strong evidence that the formation of inflammation-associated and other types of amyloid is promoted by heparan sulfate (HS). Data presented herein demonstrate that both mouse and human apoSAA contain binding sites that are specific for heparin and HS, with no binding for the other major glycosaminoglycans detected. Cyanogen bromide-generated peptides of mouse apoSAA1 and apoSAA2 were screened for heparin binding activity. Two peptides, an apoSAA1-derived 80-mer (residues 24-103) and a smaller carboxyl-terminal 27-mer peptide of apoSAA2 (residues 77-103), were retained by a heparin column. A synthetic peptide corresponding to the CNBr-generated 27-mer also bound heparin, and by substituting or deleting one or more of its six basic residues (Arg-83, His-84, Arg-86, Lys-89, Arg-95, and Lys-102), their relative importance for heparin and HS binding was determined. The Lys-102 residue appeared to be required only for HS binding. The residues Arg-86, Lys-89, Arg-95, and Lys-102 are phylogenetically conserved suggesting that the heparin/HS binding activity may be an important aspect of the function of apoSAA. HS linked by its carboxyl groups to an Affi-Gel column or treated with carbodiimide to block its carboxyl groups lost the ability to bind apoSAA. HDL-apoSAA did not bind to heparin; however, it did bind to HS, an interaction to which apoA-I contributed. Results from binding experiments with Congo Red-Sepharose 4B columns support the conclusions of a recent structural study which found that heparin binding domains have a common spatial distance of about 20 A between their two outer basic residues. Our present work provides direct evidence that apoSAA can associate with HS (and heparin) and that the occupation of its binding site by HS, and HS analogs, likely caused the previously reported increase in amyloidogenic conformation (beta-sheet) of apoSAA2 (McCubbin, W. D., Kay, C. M., Narindrasorasak, S., and Kisilevsky, R. (1988) Biochem. J. 256, 775-783) and their amyloid-suppressing effects in vivo (Kisilevsky, R., Lemieux, L. J., Fraser, P. E., Kong, X., Hultin, P. G., and Szarek, W. A. (1995) Nat. Med. 1, 143-147), respectively.

One of the most clinically aggressive cancers associated with neurofibromatosis 1 (NF1) is the malignant peripheral nerve sheath tumor (MPNST). To determine the incidence and relative risk (RR) of MPNSTs in individuals with NF1, 1,475 individuals with NF1 were included from a cohort of patients examined by a single experienced geneticist from 1977 to 1996. The end points were incidence of MPNST, relative risk of MPNST, and relative risk associated with specific NF1 physical findings. Thirty-four individuals were identified with MPNST (2%). The relative risk of MPNST was higher than expected with an RR value of 113 (95% confidence interval [CI] = 78-158). The average 10-year annual incidence of MPNST between the second and fifth decade of life was roughly the same with a range of 0.0013 and 0.0068 MPNST per patient year. Most lesions occurred in the limbs (n = 18; 53%), and those with limb lesions survived longer than those with nonlimb MPNSTs. Pain associated with a mass was the greatest risk factor associated with MPNST development (RR = 31.4; 95% CI = 13.2-75.1). Further biological and epidemiological studies are needed to determine other factors that influence the risk of MPNST development in individuals affected with NF1. Am. J. Med. Genet. 93:388-392, 2000. Published 2000 Wiley-Liss, Inc.

OBJECTIVE

To evaluate long-term ipsilateral hearing preservation in patients who underwent cochlear implantation for the combined electric acoustic stimulation of the auditory system.

METHODS

This was a prospective observational study conducted at a tertiary referral center. Twenty-three subjects were implanted with the MED-EL C40+ standard or C40+ medium electrode using an atraumatic surgical protocol via an anterior-inferior cochleostomy approach. The desired insertion depth was 18-24 mm or 360 degrees. All patients showed significant low-frequency hearing prior to surgery and monosyllabic word scores did not exceed 40% in the best aided condition. Pure-tone audiometry was performed prior to implantation and at distinct intervals after surgery.

RESULTS

Nine patients (39.1%) showed complete pure-tone audiometric hearing preservation (0-10 dB) over an average of 29 months. Seven subjects (30.4%) showed partial preservation of residual hearing (hearing loss 15-40 dB) until an average of 25 months. Delayed loss of residual hearing was observed in 5 cases (21.7%) and 2 patients (8.6%) completely lost residual hearing during or immediately after surgery. Freiburger Monosyllabic word understanding scores in a group of patients with complete hearing preservation increased from 13.1% preoperatively to 75% in the electric acoustic stimulation condition.

CONCLUSIONS

This study documents that complete and partial preservation of ipsilateral hearing after cochlear implantation can be achieved in about 70% of cases over an average period of 27.25 months when using 360 degrees electrode insertions.

Recently we reported that rapid killing of Escherichia coli by granulocytes or granulocyte fractions is accompanied by an equally rapid and discrete increase in permeability of the microbial envelope (Beckerdite, Mooney, Weiss, Franson, and Elsbach. 1974. J. Exp. Med. 140: 396-409). Most of this permeability-increasing activity (PI) is found in a crude granule preparation. PI is quantitatively recovered in a 23,000-g supernatant fraction (Sup II) after sulfuric acid extraction of granulocyte homogenates prepared in water. PI is nondialyzable, destroyed by pronase and trypsin, stable at 4degreesC for at least 2 mo, and destroyed by heating at 94degreesC. Anionic substances, such as heparin sulfate and isolated E. coli lipopolysaccharide, bind to and inhibit PI. PI has been purified up to 1,000-fold from homogenate in a yield of 50percent by acid extraction and carboxymethyl-Sephadex chromatography. Such purified fractions have bactericidal activity that equals that of disrupted granulocytes and Sup II, are similarly enriched with respect to granule-associated phospholipase, and protease activities. Whereas E. coli, sensitive to PI, binds or inactivates solubilized PI, a resistant strain of Serratia marcescens does not. Binding of PI to sensitive microorganisms seems to be necessary for expression of its biological activity since both the apparent binding to and the biological effect of PI on E. coli are completely blocked by 10-20 mM Mg2+ or Ca2+. Mg2+ or Ca2+ can reverse the effect on E. coli permeability produced by Sup II or the carboxymethyl-Sephadex fraction but not that produced by granulocyte homogenate. The close association of bactericidal, phospholipase A2, and permeability-increasing activities towards several gram-negative bacterial species suggests that they may be related.

The accumulation of somatic mutants in splenic B lymphocytes early after primary immunization with the hapten (4-hydroxy-3-nitro-phenyl)acetyl (NP) coupled to chicken gamma globulin (CG) was determined. Rearranged V186.2 heavy chain genes were amplified by the polymerase chain reaction from genomic DNA and subjected to nucleotide sequence analysis. Somatic antibody mutants become detectable on day 6 after immunization, and most of the somatic mutations accumulating in the memory compartment are introduced until day 14. At this time strong selection for mutants expressing high binding affinity for NP is apparent. Extrapolation from the mutation frequency increases between day 6 and day 14 to the previously determined mutation frequency at week 6 (Weiss. U. and Rajewsky, K., J. Exp. Med. 1990, 172: 1681) leads to the prediction that the process of mutant generation ceases to operate around day 22 after primary immunization.

Several reviews have highlighted the importance of local tissue production of components of the renin-angiotensin system (RAS) [Bader, M., Ganten, D., 2008. Update on tissue renin-angiotensin systems. J. Mol. Med. 86, 615-621; Krop, M., Danser, A.H., 2008. Circulating versus tissue renin-angiotensin system: on the origin of (pro)renin. Curr. Hypertens. Rep. 10, 112-118; Paul, M., Poyan Mehr, A., Kreutz, R., 2006. Physiology of local renin-angiotensin systems. Physiol. Rev. 86, 747-803]. While the concept of tissue RAS is gaining more widespread acceptance, the concept of local angiotensin II (AngII) production, acting in coordinate or independently of the endocrine RAS, continues to be debated. The primary reasons that local AngII production has been studied by many investigators are that components of the RAS are expressed by multiple cell types, and that the endocrine RAS cannot fully explain all effects of AngII. Moreover, through the development and study of genetically altered models for over-expression or knockdown of individual RAS components within specific cell types, it is becoming increasingly more evident that local RAS contribute to effects of AngII in normal physiology and disease. The purpose of this review is to define the presence and physiological significance of a local RAS in adipose tissue in relation to cardiovascular disease.

The complete nucleotide sequence of the cap3A gene of Streptococcus pneumoniae, which is directly responsible for the transformation of some unencapsulated, serotype 3 mutants to the encapsulated phenotype, has been determined. This gene encodes a protein of 394 amino acids with a predicted M(r) of 44,646. Twelve independent cap3A mutations have been mapped by genetic transformation, and three of them have been sequenced. Sequence comparisons revealed that cap3A was very similar (74.4%) to the hasB gene of Streptococcus pyogenes, which encodes a UDP-glucose dehydrogenase (UDP-GlcDH) that catalyzes the conversion of UDP-glucose to UDP-glucuronic acid, the donor substances in the pneumococcal type 3 capsular polysaccharide. Furthermore, a PCR-generated cap3A+ gene restored encapsulation in our cap3A mutants as well as in a mutant previously characterized as deficient in UDP-GlcDH (R. Austrian, H. P. Bernheimer, E.E.B. Smith, and G.T. Mills, J. Exp. Med. 110:585-602, 1959). These results support the conclusion that cap3A codes for UDP-GlcDH. We have also identified a region upstream of cap3A that should contain common genes necessary for the production of capsule of any type. Pulsed-field gel electrophoresis and Southern blotting showed that the capsular genes specific for serotype 3 are located near the genes encoding PBP 2X and PBP 1A in the S. pneumoniae chromosome, whereas copies of the common genes (or part of them) appear to be present in different locations in the genome.

The selective reversible S-glutathiolation of specific SERCA (sarcoplasmic/endoplasmic-reticulum Ca2+-ATPase) cysteine residues represents a novel physiologic pathway of NO (nitric oxide)-dependent arterial smooth muscle relaxation [Adachi, Weisbrod, Pimentel, Ying, Sharov, Schöneich and Cohen (2004) Nat. Med. 10, 1200-1207]. This mechanism may be impaired through the irreversible oxidation of functionally important cysteine residues as a consequence of oxidative stress and aging. To establish whether in vivo aging and in vitro oxidation by peroxynitrite result in the loss of such functionally important cysteine residues of SERCA, we have developed and optimized a quantitative method to monitor the oxidation state of the individual SERCA cysteine residues using a maleimide-based fluorescence dye, TG1 (ThioGlo 1), as a label for cysteine residues that have not been altered by oxidation and are not involved in disulphide bridges. A high efficiency for TG1 labelling of such residues and the chemical structure of cysteine-TG1 adducts were validated by MS analysis of model peptides, model proteins and rat skeletal muscle SERCA1. Tryptic peptides containing 18 out of a total of 24 cysteine residues were identified by HPLC-ESI (electrospray ionization)-MS/MS (tandem MS). Two cysteine residues, at positions 344 and 349, were detected in the form of an internal disulphide bridge, and another 16 were found to be labelled with TG1. Using HPLC-ESI-MS, we quantitatively mapped peroxynitrite oxidation of eight cysteine residues (positions 364, 417, 420, 498, 525, 674, 675 and 938), some of which are involved in the control of SERCA activity. Biological aging resulted in the partial modification of cysteine residues 377, 498, 525, 561, 614, 636, 674, 675, 774 and 938. Neither peroxynitrite exposure nor biological aging affected the apparent SERCA1 ATP affinity. Our data show an age-dependent loss of cysteine residues (approx. 2.8 mol of cysteine/mol of SERCA1), which may be partially responsible for the age-dependent decrease in the specific Ca2+-ATPase activity (by 40%).

The objective of this study was to compare the effects of linoleic acid (cis,cis-C18:2(n-6)) and its hydrogenation products elaidic (trans-C18:1(n-9)) and stearic acid (C18:0) on serum lipoprotein levels in humans. Twenty-six men and 30 women, all normolipemic and apparently healthy, completed the trial. Three experimental diets were supplied to every subject for 3 weeks each, in random order (multiple cross-over). The Linoleate-diet provided 12.0% of total energy intake as linoleic acid, 2.8% as stearic acid, and 0.1% as trans fatty acids. The Stearate-diet supplied 3.9 energy % as linoleic acid, 11.8% stearic acid, and 0.3% trans fatty acids. The Trans-diet provided 3.8 energy % as linoleic acid, 3.0% stearic acid, and 7.7% as monounsaturated trans fatty acids, largely elaidic acid (trans-C18:1(n-9)). Other nutrients were constant. Fasting blood was sampled at the end of each dietary period. Mean (+/- SD) serum LDL cholesterol was 109 +/- 24 mg/dl (2.83 +/- 0.63 mmol/l) on the Linoleate-diet. It rose to 116 +/- 27 mg/dl (3.00 +/- 0.71 mmol/l) on the Stearate-diet (change, 7 mg/dl or 0.17 mmol/l, P = 0.0008) and to 119 +/- 25 mg/dl (3.07 +/- 0.65 mmol/l) on the Trans-diet (change, 9 mg/dl or 0.24 mmol/l, P less than 0.0001). High density lipoprotein (HDL) cholesterol decreased by 2 mg/dl (0.06 mmol/l, P less than 0.0001) on the Stearate-diet and by 4 mg/dl (0.10 mmol/l, P less than 0.0001) on the Trans-diet, both relative to linoleic acid. Our findings show that 7.7% of energy (mean, 24 g/day) of trans fatty acids in the diet significantly lowered HDL cholesterol and raised LDL cholesterol relative to linoleic acid. Combination with earlier results (Mensink, R. P., and M. B. Katan. 1990. N. Engl. J. Med. 323: 439-445) suggests a linear dose-response relation. Replacement of linoleic acid by stearic acid also caused somewhat lower HDL cholesterol and higher LDL cholesterol levels. Hydrogenation of linoleic acid to either stearic or trans fatty acids produces fatty acids that may increase LDL and decrease HDL cholesterol relative to linoleic acid itself.

Increased homocysteine levels are associated with various pathological conditions in humans, including stroke and cardiovascular disorders. Homocysteine acts as an excitatory amino acid in vivo and may influence the threshold of migraine headache. Frosst et al. [1995] reported an association between the homozygous C677T mutation in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene and serum homocysteine levels. This study was designed to determine the prevalence of the MTHFR mutation in Japanese patients with migraine and tension-type headache (TH). Seventy-four patients with migraine headaches (22 with aura and 52 without aura), 47 with THs, and 261 normal controls were recruited. Genotyping of MTHFR C677T polymorphism was performed by polymerase chain reaction-restriction fragment length polymorphism. We detected that the incidence of the homozygous transition (T/T) in migraine sufferers (20.3%) was significantly higher than that in controls (9.6%). Moreover, the frequency of the T/T genotype in individuals with migraine headaches with aura was remarkably high (40.9%). The MTHFR T allele was more frequent in the migraine group than in the control group. Our results support the conclusion that the MTHFR gene, causing mild hyperhomocysteinemia may be a genetic risk factor for migraine. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 96:762-764, 2000.

Delta-9-tetrahydrocannabinol (THC) is an effective antiemetic as compared with placebos in patients receiving chemotherapy for cancer. In this study we compared THC with prochlorperazine (compazine) in a randomized, double-blind, crossover trial with patients who had failed to benefit from standard antiemetic therapy. Regardless of the emetic activity of the chemotherapeutic agents, there were more complete responses to THC courses (in 36 of 79 courses) than to prochlorperazine (in 16 of 78 courses). Of 25 patients who were treated with both drugs and who expressed a preference, 20 preferred THC (P = 0.005). Among patients under 20 years of age there was a higher proportion of complete responses to THC courses (15 of 20) than among older patients (21 of 59 courses; P = 0.004). Increased food intake occurred more frequently with THC (P = 0.008) and was associated with the presence of a "high." Of 36 THC courses resulting in complete antiemetic responses, 32 were associated with a high. We conclude that THC is an effective antiemetic in many patients who receive chemotherapy for cancer and for whom other antiemetics are ineffective. (N Engl J Med 302:135--138, 1980).

The 195-kDa merozoite protein synthesized in schizonts of Plasmodium falciparum (Holder, A. A., and Freeman, R. R. (1982) J. Exp. Med. 156, 1528-1538) contains ester-linked fatty acid. Enzymatic treatment of the purified acylated protein established that the lipid is present as sn-1,2-diacyl glycerol, most probably linked to a phosphodiester at the 3-position of glycerol. The phosphodiglyceride is not directly esterified to an amino acid residue on the polypeptide backbone. The 195-kDa protein is processed to three fragments (83, 42, and 19 kDa) on the surface of free merozoites (Holder, A. A., and Freeman, R. R. (1984) J. Exp. Med. 160, 624-629), of which only the 42-kDa polypeptide is acylated.

The use of nanoscale materials (e.g., nanoparticles, nanowires, and nanorods) for electrochemical biosensing has seen explosive growth in recent years following the discovery of carbon nanotubes by Sumio Ijima in 1991. Although the resulting label-free sensors could potentially simplify the molecular recognition process, there are several important hurdles to be overcome. These include issues of validating the biosensor on statistically large population of real samples rather than the commonly reported relatively short synthetic oligonucleotides, pristine laboratory standards or bioreagents; multiplexing the sensors to accommodate high-throughput, multianalyte detection as well as application in complex clinical and environmental samples. This article reviews the status of biomolecular recognition using electrochemical detection by analyzing the trends, limitations, challenges and commercial devices in the field of electrochemical biosensors. It provides a survey of recent advances in electrochemical biosensors including integrated microelectrode arrays with microfluidic technologies, commercial multiplex electrochemical biosensors, aptamer-based sensors, and metal-enhanced electrochemical detection (MED), with limits of detection in the attomole range. Novel applications are also reviewed for cancer monitoring, detection of food pathogens, as well as recent advances in electrochemical glucose biosensors.