Trinucleotide repeat length instability and age of onset in Huntington's disease

The initial observation of an expanded and unstable trinucleotide repeat in the Huntington's disease gene has now been confirmed and extended in 150 independent Huntington's disease families. HD chromosomes contained 37-86 repeat units, whereas normal chromosomes displayed 11-34 repeats. The HD repeat length was inversely correlated with the age of onset of the disorder. The HD repeat was unstable in more than 80% of meiotic transmissions showing both increases and decreases in size with the largest increases occurring in paternal transmissions. The targeting of spermatogenesis as a particular source of repeat instability is reflected in the repeat distribution of HD sperm DNA. The analysis of the length and instability of individual repeats in members of these families has profound implications for presymptomatic diagnosis.

High resolution structures of HIV-1 RT from four RT-inhibitor complexes

We have determined the structures of four complexes of HIV-1 reverse transcriptase with non-nucleoside inhibitors, three fully refined at high resolution. The highest resolution structure is of the RT-nevirapine complex which has an R-factor of 0.186 and a root-mean-square bond length deviation of 0.015 A for all data to 2.2 A. The structures reveal a common mode of binding for these chemically diverse compounds. The common features of binding are largely hydrophobic interactions and arise from induced shape complementarity achieved by conformational rearrangement of the enzyme and conformational/configurational rearrangement of the compounds.

Testosterone replacement in older hypogonadal men: a 12-month randomized controlled trial

A decline in testicular function is recognized as a common occurrence in older men. However data are sparse regarding the effects of hypogonadism on age-associated physical and cognitive declines. This study was undertaken to examine the year-long effects of testosterone administration in this patient population. Fifteen hypogonadal men (mean age 68 +/- 6 yr) were randomly assigned to receive a placebo, and 17 hypogonadal men (mean age 65 +/- 7 yr) were randomly assigned to receive testosterone. Hypogonadism was defined as a bioavailable testosterone <60 ng/dL. The men received injections of placebo or 200 mg testosterone cypionate biweekly for 12 months. The main outcomes measured included grip strength, hemoglobin, prostate-specific antigen, leptin, and memory. Testosterone improved bilateral grip strength (P < 0.05 by ANOVA) and increased hemoglobin (P < 0.001 by ANOVA). The men assigned to testosterone had greater decreases in leptin than those assigned to the control group (mean +/- SEM: -2.0 +/- 0.9 ng/dL vs. 0.8 +/- 0.7 ng/dL; P < 0.02). There were no significant changes in prostate-specific antigen or memory. Three subjects receiving placebo and seven subjects receiving testosterone withdrew from the study. Three of those seven withdrew because of an abnormal elevation in hematocrit. Testosterone supplementation improved strength, increased hemoglobin, and lowered leptin levels in older hypogonadal men. Testosterone may have a role in the treatment of frailty in males with hypogonadism; however, older men receiving testosterone must be carefully monitored because of its potential risks.

A Randomized Trial of Factor VIII and Neutralizing Antibodies in Hemophilia A

BACKGROUND

The development of neutralizing anti-factor VIII alloantibodies (inhibitors) in patients with severe hemophilia A may depend on the concentrate used for replacement therapy.

METHODS

We conducted a randomized trial to assess the incidence of factor VIII inhibitors among patients treated with plasma-derived factor VIII containing von Willebrand factor or recombinant factor VIII. Patients who met the eligibility criteria (male sex, age <6 years, severe hemophilia A, and no previous treatment with any factor VIII concentrate or only minimal treatment with blood components) were included from 42 sites.

RESULTS

Of 303 patients screened, 264 underwent randomization and 251 were analyzed. Inhibitors developed in 76 patients, 50 of whom had high-titer inhibitors (≥5 Bethesda units). Inhibitors developed in 29 of the 125 patients treated with plasma-derived factor VIII (20 patients had high-titer inhibitors) and in 47 of the 126 patients treated with recombinant factor VIII (30 patients had high-titer inhibitors). The cumulative incidence of all inhibitors was 26.8% (95% confidence interval [CI], 18.4 to 35.2) with plasma-derived factor VIII and 44.5% (95% CI, 34.7 to 54.3) with recombinant factor VIII; the cumulative incidence of high-titer inhibitors was 18.6% (95% CI, 11.2 to 26.0) and 28.4% (95% CI, 19.6 to 37.2), respectively. In Cox regression models for the primary end point of all inhibitors, recombinant factor VIII was associated with an 87% higher incidence than plasma-derived factor VIII (hazard ratio, 1.87; 95% CI, 1.17 to 2.96). This association did not change in multivariable analysis. For high-titer inhibitors, the hazard ratio was 1.69 (95% CI, 0.96 to 2.98). When the analysis was restricted to recombinant factor VIII products other than second-generation full-length recombinant factor VIII, effect estimates remained similar for all inhibitors (hazard ratio, 1.98; 95% CI, 0.99 to 3.97) and high-titer inhibitors (hazard ratio, 2.59; 95% CI, 1.11 to 6.00).

CONCLUSIONS

Patients treated with plasma-derived factor VIII containing von Willebrand factor had a lower incidence of inhibitors than those treated with recombinant factor VIII. (Funded by the Angelo Bianchi Bonomi Foundation and others; ClinicalTrials.gov number, NCT01064284; EudraCT number, 2009-011186-88.).

Mechanism of inhibition of HIV-1 reverse transcriptase by non-nucleoside inhibitors

The structure of unliganded HIV-1 reverse transcriptase has been determined at 2.35 A resolution and refined to an R-factor of 0.219 (for all data) with good stereochemistry. The unliganded structure was produced by soaking out a weak binding non-nucleoside inhibitor, HEPT, from pregrown crystals. Comparison with the structures of four different RT and non-nucleoside inhibitor complexes reveals that only minor domain rearrangements occur, but there is a significant repositioning of a three-stranded beta-sheet in the p66 subunit (containing the catalytic aspartic acid residues 110, 185 and 186) with respect to the rest of the polymerase site. This suggests that NNIs inhibit RT by locking the polymerase active site in an inactive conformation, reminiscent of the conformation observed in the inactive p51 subunit.

Evidence for regulation of the PTEN tumor suppressor by a membrane-localized multi-PDZ domain containing scaffold protein MAGI-2

PTEN is a tumor suppressor gene mutated in human cancers. Although many mutations target the phosphatase domain, others create a truncated protein lacking the C-terminal PDZ-binding motif or a protein that extends beyond the PDZ-binding motif. Using the yeast two-hybrid system, we isolated a membrane-associated guanylate kinase family protein with multiple PDZ domains [AIP-1 (atrophin interacting protein 1), renamed MAGI-2 (membrane associated guanylate kinase inverted-2)]. MAGI-2 contains eight potential protein-protein interaction domains and is localized to tight junctions in the membrane of epithelial cells. PTEN binds to MAGI-2 through an interaction between the PDZ-binding motif of PTEN and the second PDZ domain of MAGI-2. MAGI-2 enhances the ability of PTEN to suppress Akt activation. Furthermore, certain PTEN mutants have reduced stability, which is restored by adding the minimal PDZ-binding motif back to the truncated protein. We propose that MAGI-2 improves the efficiency of PTEN signaling through assembly of a multiprotein complex at the cell membrane.

Complexes of HIV-1 reverse transcriptase with inhibitors of the HEPT series reveal conformational changes relevant to the design of potent non-nucleoside inhibitors

Crystal structures of HIV-1 reverse transcriptase (RT) complexed with a range of chemically diverse non-nucleoside inhibitors (NNIs) have shown a single pocket in which the inhibitors bind and details of the inhibitor-protein interactions. To delineate the structural requirements for an effective inhibitor, we have determined the structures of three closely related NNIs which vary widely in their potencies. Crystal structures of HIV-1 RT complexed with two very potent inhibitors, MKC-442 and TNK-651, at 2.55 angstroms resolution complement our previous analysis of the complex with the less effective inhibitor, HEPT. These structures reveal conformational changes which correlate with changes in potency. We suggest that a major determinant of increased potency in the analogues of HEPT is an improved interaction between residue Tyr181 in the protein and the 6-benzyl ring of the inhibitors which stabilizes the structure of the complex. This arises through a conformational switching of the protein structure triggered by the steric bulk of the 5-substituent of the inhibitor pyrimidine ring.

Endothelial NADPH oxidase as the source of oxidants in lungs exposed to ischemia or high K+

We have previously demonstrated the generation of reactive oxygen species (ROS) in cultured bovine pulmonary artery endothelial cells (BPAECs) and in isolated perfused rat lungs exposed to high K+ and during global lung ischemia. The present study evaluates the NADPH oxidase pathway as a source of ROS in these models. ROS production, detected by oxidation of the fluorophore, dichlorodihydrofluorescein, increased 2.5-fold in BPAECs and 6-fold in rat or mouse lungs exposed to high (24 mmol/L) K+. ROS generation was markedly inhibited by diphenyliodonium, a flavoprotein inhibitor, and by the synthetic peptide PR-39, an inhibitor of NADPH oxidase assembly, whereas allopurinol had no effect. With ischemia (1 hour), ROS generation by rat and mouse lungs increased 7-fold; PR-39 showed concentration-dependent inhibition of ROS production, with 50% inhibition at 3 micromol/L PR-39. ROS production in lungs exposed to high K+ or ischemia was essentially abolished in mice with a "knockout" of gp91(phox), a membrane-localized cytochrome component of NADPH oxidase; increased ROS production by these lungs after anoxia/reoxygenation was similar to control. PR-39 also inhibited ischemia and the high K+-mediated increase in lung thiobarbituric acid reactive substance. Western blotting of BPAECs and immunocytochemistry of BPAECs and rat and mouse lungs showed the presence of p47phox, a cytoplasmic component of NADPH oxidase and the putative target for PR-39 inhibition. In situ fluorescence imaging in the intact lung demonstrated that the increased dichlorofluorescein fluorescence in these models of ROS generation was localized primarily to the pulmonary endothelium. These studies demonstrate that ROS production in lungs exposed to ischemia or high K+ results from assembly and activation of a membrane-associated NAPDH oxidase of the pulmonary endothelium.

Guidelines on use of anti-IFN-beta antibody measurements in multiple sclerosis: report of an EFNS Task Force on IFN-beta antibodies in multiple sclerosis

Therapy-induced binding and neutralizing antibodies is a major problem in interferon (IFN)-beta treatment of multiple sclerosis. The objective of this study was to provide guidelines outlining the methods and clinical use of the measurements of binding and neutralizing antibodies. Systematic search of the Medline database for available publications on binding and neutralizing antibodies was undertaken. Appropriate publications were reviewed by one or more of the task force members. Grading of evidence and recommendations was based on consensus by all task force members. Measurements of binding antibodies are recommended for IFN-beta antibody screening before performing a neutralizing antibody (NAB) assay (Level A recommendation). Measurement of NABs should be performed in specialized laboratories with a validated cytopathic effect assay or MxA production assay using serial dilution of the test sera. The NAB titre should be calculated using the Kawade formula (Level A recommendation). Tests for the presence of NABs should be performed in all patients at 12 and 24 months of therapy (Level A recommendation). In patients who remain NAB-negative during this period measurements of NABs can be discontinued (Level B recommendation). In patient with NABs, measurements should be repeated, and therapy with IFN-beta should be discontinued in patients with high titres of NABs sustained at repeated measurements with 3- to 6-month intervals (Level A recommendation).

Anthropoid origins

Recent fossil discoveries have greatly increased our knowledge of the morphology and diversity of early Anthropoidea, the suborder to which humans belong. Phylogenetic analysis of Recent and fossil taxa supports the hypotheses that a haplorhine-strepsirrhine dichotomy existed at least at the time of the earliest record of fossil primates (earliest Eocene) and that eosimiids (middle Eocene, China) are primitive anthropoids. Functional analysis suggests that stem haplorhines were small, nocturnal, arboreal, visually oriented insectivore-frugivores with a scurrying-leaping locomotion. A change from nocturnality to diurnality was the fundamental adaptive shift that occurred at the base of the tarsier-eosimiid-anthropoid clade. Stem anthropoids remained small diurnal arborealists but adopted locomotor patterns with more arboreal quadrupedalism and less leaping. A shift to a more herbivorous diet occurred in several anthropoid lineages.

The structure of HIV-1 reverse transcriptase complexed with 9-chloro-TIBO: lessons for inhibitor design

BACKGROUND

HIV reverse transcriptase (RT) is a key target of anti-AIDS therapies. Structural studies of HIV-1 RT, unliganded and complexed with different non-nucleoside inhibitors (NNIs), have pointed to a common mode of binding and inactivation through distortion of the polymerase catalytic site by NNIs containing two hinged rings. The mode of binding of the TIBO family of inhibitors is of interest because these compounds do not fit the two-hinged-ring model.

RESULTS

The structure of HIV-1 RT complexed with 9-chloro-TIBO (R82913) has been determined at 2.6 A resolution. As reported for the lower resolution analysis of another TIBO compound, this inhibitor binds at the same site as other NNIs, but our higher resolution study reveals the Cl-TIBO is distorted from the conformation seen in crystals of the inhibitor alone. This allows Cl-TIBO to mimic the binding of NNIs containing two hinged rings. Inhibitor-protein interactions are again predominantly hydrophobic and the protein conformation corresponds to that seen in complexes with other tight-binding NNIs.

CONCLUSIONS

Although Cl-TIBO is chemically very different from other NNIs, it achieves remarkable spatial equivalence and shape complementarity with other NNIs on binding to RT. Comparison of the different RT-NNI complexes suggests modifications to the TIBO group of inhibitors which might enhance their binding and hence, potentially, their therapeutic efficacy.

Basicranial flexion, relative brain size, and facial kyphosis in Homo sapiens and some fossil hominids

Comparative work among nonhominid primates has demonstrated that the basicranium becomes more flexed with increasing brain size relative to basicranial length and as the upper and lower face become more ventrally deflected (Ross and Ravosa [1993] Am. J. Phys. Anthropol. 91:305-324). In order to determine whether modern humans and fossil hominids follow these trends, the cranial base angle (measure of basicranial flexion), angle of facial kyphosis, and angle of orbital axis orientation were measured from computed tomography (CT) scans of fossil hominids (Sts 5, MLD 37/38, OH9, Kabwe) and lateral radiographs of 99 extant humans. Brain size relative to basicranial length was calculated from measures of neurocranial volume and basicranial length taken from original skulls, radiographs, CT scans, and the literature. Results of bivariate correlation analyses revealed that among modern humans basicranial flexion and brain size/basicranial length are not significantly correlated, nor are the angles of orbital axis orientation and facial kyphosis. However, basicranial flexion and orbit orientation are significantly positively correlated among the humans sampled, as are basicranial flexion and the angle of facial kyphosis. Relative to the comparative sample from Ross and Ravosa (1993), all hominids have more flexed basicrania than other primates: Archaic Homo sapiens, Homo erectus, and Australopithecus africanus do not differ significantly from Modern Homo sapiens in their degree of basicranial flexion, although they differ widely in their relative brain size. Comparison of the hominid values with those predicted by the nonhominid reduced major-axis equations reveal that, for their brain size/basicranial length, Archaic and Modern Homo sapiens have less flexed basicrania than predicted. H. erectus and A. africanus have the degree of basicranial flexion predicted by the nonhominid reduced major-axis equation. Modern humans have more ventrally deflected orbits than all other primates and, for their degree of basicranial flexion, have more ventrally deflected orbits than predicted by the regression equations for hominoids. All hominoids have more ventrally deflected orbital axes relative to their palate orientation than other primates. It is argued that hominids do not strictly obey the trend for basicranial flexion to increase with increasing relative brain size because of constraints on the amount of flexion that do not allow it to decrease much below 90 degrees. Therefore, if basicranial flexion is a mechanism for accommodating an expanding brain among non-hominid primates, other mechanisms must be at work among hominids.

Appearance and disappearance of neutralizing antibodies during interferon-beta therapy

BACKGROUND

Neutralizing antibodies (NABs) occur frequently in patients receiving interferon (IFN)-beta for multiple sclerosis (MS), but it is unclear whether occurrence of NABs is predictive for the persistence of NABs during continued IFN-beta therapy.

METHODS

The authors used an antiviral neutralization bioassay to measure NABs blindly from 6 months up to 78 months in patients with MS who were followed for at least 24 months during treatment with IFN-beta. Patients were classified into three groups: 1) persistently NAB-negative patients, defined as patients without any positive samples at any time; 2) definitely NAB-positive patients, defined as patients who had at least two consecutive positive samples; and 3) patients with fluctuating NAB-positive and NAB-negative samples.

RESULTS

A total of 455 patients were included in the study. Overall, 52.3% of the patients were persistently NAB-negative, 40.9% became definitely NAB-positive, and the remaining 6.8% were fluctuating. More patients treated with IFN-beta-1a (Avonex) remained NAB-negative (p < 0.0001), whereas there was no difference between IFN-beta-1b (Betaferon) and IFN-beta-1a (Rebif). Patients who have remained NAB-negative during the first 24 months of therapy rarely developed NABs. On the contrary, the majority of patients, who had been NAB-positive from 12 through 30 months after start of therapy, remained NAB-positive.

CONCLUSIONS

NABs should be measured in all patients treated with IFN-beta. If patients have been persistently NAB-negative for 24 months, measurements can be discontinued. Patients who have been NAB-positive for a period of 18 months or more usually remain NAB-positive for a long time.

Severe ovarian hyperstimulation syndrome using agonists of gonadotropin-releasing hormone for in vitro fertilization: a European series and a proposal for prevention

Severe ovarian hyperstimulation syndrome (OHSS) was recorded in 8 of 413 patients after the use of gonadotropin-releasing hormone agonists (GnRH-a) associated with gonadotropins for in vitro fertilization. Seven of the 8 patients were pregnant. Common factors associated with the development of OHSS were high serum estradiol values on the day of ovulation induction and many follicles greater than or equal to 12 mm. Based on this experience, a new therapeutic schedule was used in a group of 10 patients who, after GnRH-a and gonadotropin stimulation, were judged to be at high risk of OHSS on the day of human chorionic gonadotropin (hCG). No hCG was administered and gonadotropins were stopped. The administration of GnRH-a was continued and, after a further period of pituitary desensitization, follicular stimulation was recommended with a lower dose of gonadotropins. No cases of OHSS occurred and 3 patients became pregnant.

Interaction of normal and expanded CAG repeat sizes influences age at onset of Huntington disease

Huntington disease (HD) is a neurodegenerative disorder caused by the abnormal expansion of CAG repeats in the HD gene on chromosome 4p16.3. Past studies have shown that the size of expanded CAG repeat is inversely associated with age at onset (AO) of HD. It is not known whether the normal Huntington allele size influences the relation between the expanded repeat and AO of HD. Data collected from two independent cohorts were used to test the hypothesis that the unexpanded CAG repeat interacts with the expanded CAG repeat to influence AO of HD. In the New England Huntington Disease Center Without Walls (NEHD) cohort of 221 HD affected persons and in the HD-MAPS cohort of 533 HD affected persons, we found evidence supporting an interaction between the expanded and unexpanded CAG repeat sizes which influences AO of HD (P = 0.08 and 0.07, respectively). The association was statistically significant when both cohorts were combined (P = 0.012). The estimated heritability of the AO residual was 0.56 after adjustment for normal and expanded repeats and their interaction. An analysis of tertiles of repeats sizes revealed that the effect of the normal allele is seen among persons with large HD repeat sizes (47-83). These findings suggest that an increase in the size of the normal repeat may mitigate the expression of the disease among HD affected persons with large expanded CAG repeats.

Marie M, Stickney K, VanBuecken D, Vellek B, Webber C, Allen L, Bollyk J, Hilderman N, Ismail H, Lamola S, Sanda S, Vendettuoli H, Tridgell D, Monzavi R, Bock M, Fisher L, Halvorson M, Jeandron D, Kim M, Wood J, Geffner M, Kaufman F, Parkman R, Salazar C, Goland R, Clynes R, Cook S, Freeby M, Gallagher MP, Gandica R, Greenberg E, Kurland A, Pollak S, Wolk A, Chan M, Koplimae L, Levine E, Smith K, Trast J, DiMeglio L, Blum J, Evans-Molina C, Hufferd R, Jagielo B, Kruse C, Patrick V, Rigby M, Spall M, Swinney K, Terrell J, Christner L, Ford L, Lynch S, Menendez M, Merrill P, Pescovitz M, Rodriguez H, Alleyn C, Baidal D, Fay S, Gaglia J, Resnick B, Szubowicz S, Weir G, Benjamin R, Conboy D, deManbey A, Jackson R, Jalahej H, Orban T, Ricker A, Wolfsdorf J, Zhang HH, Wilson D, Aye T, Baker B, Barahona K, Buckingham B, Esrey K, Esrey T, Fathman G, Snyder R, Aneja B, Chatav M, Espinoza O, Frank E, Liu J, Perry J, Pyle R, Rigby A, Riley K, Soto A, Gitelman S, Adi S, Anderson M, Berhel A, Breen K, Fraser K, Gerard-Gonzalez A, Jossan P, Lustig R, Moassesfar S, Mugg A, Ng D, Prahalod P, Rangel-Lugo M, Sanda S, Tarkoff J, Torok C, Wesch R, Aslan I, Buchanan J, Cordier J, Hamilton C, Hawkins L, Ho T, Jain A, Ko K, Lee T, Phelps S, Rosenthal S, Sahakitrungruang T, Stehl L, Taylor L, Wertz M, Wong J, Philipson L, Briars R, Devine N, Littlejohn E, Grant T, Gottlieb P, Klingensmith G, Steck A, Alkanani A, Bautista K, Bedoy R, Blau A, Burke B, Cory L, Dang M, Fitzgerald-Miller L, Fouts A, Gage V, Garg S, Gesauldo P, Gutin R, Hayes C, Hoffman M, Ketchum K, Logsden-Sackett N, Maahs D, Messer L, Meyers L, Michels A, Peacock S, Rewers M, Rodriguez P, Sepulbeda F, Sippl R, Steck A, Taki I, Tran BK, Tran T, Wadwa RP, Zeitler P, Barker J, Barry S, Birks L, Bomsburger L, Bookert T, Briggs L, Burdick P, Cabrera R, Chase P, Cobry E, Conley A, Cook G, Daniels J, DiDomenico D, Eckert J, Ehler A, Eisenbarth G, Fain P, Fiallo-Scharer R, Frank N, Goettle H, Haarhues M, Harris S, Horton L, Hutton J, Jeffrrey J, Jenison R, Jones K, Kastelic W, King MA, Lehr D, Lungaro J, Mason K, Maurer H, Nguyen L, Proto A, Realsen J, Schmitt K, Schwartz M, Skovgaard S, Smith J, Vanderwel B, Voelmle M, Wagner R, Wallace A, Walravens P, Weiner L, Westerhoff B, Westfall E, Widmer K, Wright H, Schatz D, Abraham A, Atkinson M, Cintron M, Clare-Salzler M, Ferguson J, Haller M, Hosford J, Mancini D, Rohrs H, Silverstein J, Thomas J, Winter W, Cole G, Cook R, Coy R, Hicks E, Lewis N, Marks J, Pugliese A, Blaschke C, Matheson D, Sanders-Branca N, Sosenko J, Arazo L, Arce R, Cisneros M, Sabbag S, Moran A, Gibson C, Fife B, Hering B, Kwong C, Leschyshyn J, Nathan B, Pappenfus B, Street A, Boes MA, Eck SP, Finney L, Fischer TA, Martin A, Muzamhindo CJ, Rhodes M, Smith J, Wagner J, Wood B, Becker D, Delallo K, Diaz A, Elnyczky B, Libman I, Pasek B, Riley K, Trucco M, Copemen B, Gwynn D, Toledo F, Rodriguez H, Bollepalli S, Diamond F, Eyth E, Henson D, Lenz A, Shulman D, Raskin P, Adhikari S, Dickson B, Dunnigan E, Lingvay I, Pruneda L, Ramos-Roman M, Raskin P, Rhee C, Richard J, Siegelman M, Sturges D, Sumpter K, White P, Alford M, Arthur J, Aviles-Santa ML, Cordova E, Davis R, Fernandez S, Fordan S, Hardin T, Jacobs A, Kaloyanova P, Lukacova-Zib I, Mirfakhraee S, Mohan A, Noto H, Smith O, Torres N, Wherrett D, Balmer D, Eisel L, Kovalakovska R, Mehan M, Sultan F, Ahenkorah B, Cevallos J, Razack N, Ricci MJ, Rhode A, Srikandarajah M, Steger R, Russell WE, Black M, Brendle F, Brown A, Moore D, Pittel E, Robertson A, Shannon A, Thomas JW, Herold K, Feldman L, Sherwin R, Tamborlane W, Weinzimer S, Toppari J, Kallio T, Kärkkäinen M, Mäntymäki E, Niininen T, Nurmi B, Rajala P, Romo M, Suomenrinne S, Näntö-Salonen K, Simell O, Simell T, Bosi E, Battaglia M, Bianconi E, Bonfanti R, Grogan P, Laurenzi A, Martinenghi S, Meschi F, Pastore M, Falqui L, Muscato MT, Viscardi M, Castleden H, Farthing N, Loud S, Matthews C, McGhee J, Morgan A, Pollitt J, Elliot-Jones R, Wheaton C, Knip M, Siljander H, Suomalainen H, Colman P, Healy F, Mesfin S, Redl L, Wentworth J, Willis J, Farley M, Harrison L, Perry C, Williams F, Mayo A, Paxton J, Thompson V, Volin L, Fenton C, Carr L, Lemon E, Swank M, Luidens M, Salgam M, Sharma V, Schade D, King C, Carano R, Heiden J, Means N, Holman L, Thomas I, Madrigal D, Muth T, Martin C, Plunkett C, Ramm C, Auchus R, Lane W, Avots E, Buford M, Hale C, Hoyle J, Lane B, Muir A, Shuler S, Raviele N, Ivie E, Jenkins M, Lindsley K, Hansen I, Fadoju D, Felner E, Bode B, Hosey R, Sax J, Jefferies C, Mannering S, Prentis R, She J, Stachura M, Hopkins D, Williams J, Steed L, Asatapova E, Nunez S, Knight S, Dixon P, Ching J, Donner T, Longnecker S, Abel K, Arcara K, Blackman S, Clark L, Cooke D, Plotnick L, Levin P, Bromberger L, Klein K, Sadurska K, Allen C, Michaud D, Snodgrass H, Burghen G, Chatha S, Clark C, Silverberg J, Wittmer C, Gardner J, LeBoeuf C, Bell P, McGlore O, Tennet H, Alba N, Carroll M, Baert L, Beaton H, Cordell E, Haynes A, Reed C, Lichter K, McCarthy P, McCarthy S, Monchamp T, Roach J, Manies S, Gunville F, Marosok L, Nelson T, Ackerman K, Rudolph J, Stewart M, McCormick K, May S, Falls T, Barrett T, Dale K, Makusha L, McTernana C, Penny-Thomas K, Sullivan K, Narendran P, Robbie J, Smith D, Christensen R, Koehler B, Royal C, Arthur T, Houser H, Renaldi J, Watsen S, Wu P, Lyons L, House B, Yu J, Holt H, Nation M, Vickers C, Watling R, Heptulla R, Trast J, Agarwal C, Newell D, Katikaneni R, Gardner C, Del Rio A, Logan A, Collier H, Rishton C, Whalley G, Ali A, Ramtoola S, Quattrin T, Mastrandea L, House A, Ecker M, Huang C, Gougeon C, Ho J, Pacuad D, Dunger D, May J, O’Brien C, Acerini C, Salgin B, Thankamony A, Williams R, Buse J, Fuller G, Duclos M, Tricome J, Brown H, Pittard D, Bowlby D, Blue A, Headley T, Bendre S, Lewis K, Sutphin K, Soloranzo C, Puskaric J, Madison H, Rincon M, Carlucci M, Shridharani R, Rusk B, Tessman E, Huffman D, Abrams H, Biederman B, Jones M, Leathers V, Brickman W, Petrie P, Zimmerman D, Howard J, Miller L, Alemzadeh R, Mihailescu D, Melgozza-Walker R, Abdulla N, Boucher-Berry C, Ize-Ludlow D, Levy R, Swenson Brousell C, Scott R, Heenan H, Lunt H, Kendall D, Willis J, Darlow B, Crimmins N, Edler D, Weis T, Schultz C, Rogers D, Latham D, Mawhorter C, Switzer C, Spencer W, Konstantnopoulus P, Broder S, Klein J, Bachrach B, Gardner M, Eichelberger D, Knight L, Szadek L, Welnick G, Thompson B, Hoffman R, Revell A, Cherko J, Carter K, Gilson E, Haines J, Arthur G, Bowen B, Zipf W, Graves P, Lozano R, Seiple D, Spicer K, Chang A, Fregosi J, Harbinson J, Paulson C, Stalters S, Wright P, Zlock D, Freeth A, Victory J, Maheshwari H, Maheshwari A, Holmstrom T, Bueno J, Arguello R, Ahern J, Noreika L, Watson V, Hourse S, Breyer P, Kissel C, Nicholson Y, Pfeifer M, Almazan S, Bajaj J, Quinn M, Funk K, McCance J, Moreno E, Veintimilla R, Wells A, Cook J, Trunnel S, Transue D, Surhigh J, Bezzaire D, Moltz K, Zacharski E, Henske J, Desai S, Frizelis K, Khan F, Sjoberg R, Allen K, Manning P, Hendry G, Taylor B, Jones S, Couch R, Danchak R, Lieberman D, Strader W, Bencomo M, Bailey T, Bedolla L, Roldan C, Moudiotis C, Vaidya B, Anning C, Bunce S, Estcourt S, Folland E, Gordon E, Harrill C, Ireland J, Piper J, Scaife L, Sutton K, Wilkins S, Costelloe M, Palmer J, Casas L, Miller C, Burgard M, Erickson C, Hallanger-Johnson J, Clark P, Taylor W, Galgani J, Banerjee S, Banda C, McEowen D, Kinman R, Lafferty A, Gillett S, Nolan C, Pathak M, Sondrol L, Hjelle T, Hafner S, Kotrba J, Hendrickson R, Cemeroglu A, Symington T, Daniel M, Appiagyei-Dankah Y, Postellon D, Racine M, Kleis L, Barnes K, Godwin S, McCullough H, Shaheen K, Buck G, Noel L, Warren M, Weber S, Parker S, Gillespie I, Nelson B, Frost C, Amrhein J, Moreland E, Hayes A, Peggram J, Aisenberg J, Riordan M, Zasa J, Cummings E, Scott K, Pinto T, Mokashi A, McAssey K, Helden E, Hammond P, Dinning L, Rahman S, Ray S, Dimicri C, Guppy S, Nielsen H, Vogel C, Ariza C, Morales L, Chang Y, Gabbay R, Ambrocio L, Manley L, Nemery R, Charlton W, Smith P, Kerr L, Steindel-Kopp B, Alamaguer M, Tabisola-Nuesca E, Pendersen A, Larson N, Cooper-Olviver H, Chan D, Fitz-Patrick D, Carreira T, Park Y, Ruhaak R, Liljenquist D. A Type 1 Diabetes Genetic Risk Score Predicts Progression of Islet Autoimmunity and Development of Type 1 Diabetes in Individuals at Risk

OBJECTIVE

We tested the ability of a type 1 diabetes (T1D) genetic risk score (GRS) to predict progression of islet autoimmunity and T1D in at-risk individuals.

RESEARCH DESIGN AND METHODS

We studied the 1,244 TrialNet Pathway to Prevention study participants (T1D patients' relatives without diabetes and with one or more positive autoantibodies) who were genotyped with Illumina ImmunoChip (median [range] age at initial autoantibody determination 11.1 years [1.2-51.8], 48% male, 80.5% non-Hispanic white, median follow-up 5.4 years). Of 291 participants with a single positive autoantibody at screening, 157 converted to multiple autoantibody positivity and 55 developed diabetes. Of 953 participants with multiple positive autoantibodies at screening, 419 developed diabetes. We calculated the T1D GRS from 30 T1D-associated single nucleotide polymorphisms. We used multivariable Cox regression models, time-dependent receiver operating characteristic curves, and area under the curve (AUC) measures to evaluate prognostic utility of T1D GRS, age, sex, Diabetes Prevention Trial-Type 1 (DPT-1) Risk Score, positive autoantibody number or type, HLA DR3/DR4-DQ8 status, and race/ethnicity. We used recursive partitioning analyses to identify cut points in continuous variables.

RESULTS

Higher T1D GRS significantly increased the rate of progression to T1D adjusting for DPT-1 Risk Score, age, number of positive autoantibodies, sex, and ethnicity (hazard ratio [HR] 1.29 for a 0.05 increase, 95% CI 1.06-1.6; P = 0.011). Progression to T1D was best predicted by a combined model with GRS, number of positive autoantibodies, DPT-1 Risk Score, and age (7-year time-integrated AUC = 0.79, 5-year AUC = 0.73). Higher GRS was significantly associated with increased progression rate from single to multiple positive autoantibodies after adjusting for age, autoantibody type, ethnicity, and sex (HR 2.27 for GRS >0.295, 95% CI 1.47-3.51; P = 0.0002).

CONCLUSIONS

The T1D GRS independently predicts progression to T1D and improves prediction along T1D stages in autoantibody-positive relatives.

Basal metabolic rate, body weight and diet in primates: an evaluation of the evidence

The relationship between basal metabolic rate (BMR), body weight and diet is examined for primates. Contrary to the results reported in several recent works, there is no strong evidence that diet is directly linked to BMR, although a low BMR, relative to body weight, may be found in species with folivorous diets. There is some evidence that nocturnal haplorhine species have a relatively low BMR, but strepsirhines appear to have a uniformly low relative BMR regardless of their primary activity period. The evolution of BMR in primates is discussed in the light of these findings. Some predictions are made about the relative BMRs that should be found for other species whose BMR is, as yet, unknown.

Trophectoderm biopsy in human blastocysts

Trophectoderm biopsy was carried out on 47 human blastocysts. A slit was made in the zona pellucida opposite the inner cell mass by micromanipulative techniques. The human blastocyst zona offered more resistance to slitting compared to that of the mouse. After 18-24 h, controlled herniation of the trophectoderm cells was observed. These cells were biopsied when the diameter of the herniation was approximately equal to that of the blastocyst. The size of the slit and the stage of embryonic development at which slitting was performed were important for successful herniation to occur. After slitting, 76% of day 5-6 blastocysts showed herniation whilst only 42% of day 7-8 blastocysts herniated. Further development of the manipulated embryos was not apparently impaired, as hatching occurred in 44% of the former and 20% of the latter, compared with 18.1% in non-manipulated controls. The biopsied cells (approximately 10-30) usually remained in a clump but 14% formed vesicles on the day after biopsy. There was, however, no evidence of adherence to the dish or formation of monolayers. These results demonstrate the feasibility of trophectoderm biopsy in human blastocysts and that sufficient extra-embryonic material can be obtained by this technique for preimplantation diagnosis of genetic disorders.

Sex differences in energy expenditure in non-human primates

Female mammals bear the energetic costs of gestation and lactation. Therefore, it is often assumed that the overall energetic costs are greater for females than they are for males. However, the energetic costs to males of intrasex competition may also be considerable, particularly if males maintain a much larger body size than females. Using data from 19 non-human primates, this paper examines the relationship between male and female energetic costs both in the short term (daily energy expenditure) and the long term (the energetic cost of producing a single offspring). It is shown that the major determinant of sex differences in energetic costs is body size dimorphism. In the long term, the energetic costs are often greater for females, but, when male body size exceeds female body size by 60% or more, male energetic costs are greater than those for females. That is, in highly sexually dimorphic species the energetic costs of gestation and lactation for the females are matched by the energetic costs to the males of maintaining a large body size.

Phylogenetic analysis of anthropoid relationships

The relationships of anthropoids to other primates are currently debated, as are the relationships among early fossil anthropoids and crown anthropoids. To resolve these issues, data on 291 morphological characters were collected for 57 taxa of living and fossil primates and analyzed using PAUP and MacClade. The dental evidence provides weak support for the notion of an adapid origin for anthropoids, the cranial evidence supports the tarsier-anthropoid hypothesis, and the postcranial evidence supports a monophyletic Prosimii and a monophyletic Anthropoidea. Combining these data into a single data set produces almost universal support for a tarsier-anthropoid clade nested within omomyids. Eosimias and Afrotarsius are certainly members of this clade, and probably basal anthropoids, although the Shanghuang petrosal may not belong to Eosimias. The tree derived from the combined data set resembles the tree derived from the cranial data set rather than the larger dental data set. This may be attributable to relatively slower evolution in the cranial characters. The combined data set shows Anthropoidea to be monophyletic but the features traditionally held to be anthropoid synapomorphies are found to have evolved mosaically. Parapithecines are the sister taxon to crown anthropoids; qatraniines and oligopithecids are more distantly related sister taxa. There is support for a relationship of a Tarsius + Anthropoidea clade with either washakiines on Uintanius. These elements of tree topology remain fairly stable under different assumptions sets, but overall, tree topology is not robust. Previously divergent hypotheses regarding anthropoid relationships are attributable to the use of restricted data sets. This large data set enables the adapid-anthropoid hypothesis to be rejected, and unites Tarsius, Anthropoidea and Omomyiformes within a clade, Haplorhini. However, relationships among these three taxa cannot be convincingly resolved at present.

Epidemiology, treatment and outcome of candidemia: a five-year review at three Canadian hospitals

To determine treatment regimens and epidemiological patterns in the occurrence of candidemia, a review of cases occurring from 1992 to 1996 in three large Canadian hospitals, University of Alberta Hospital (UAH) and Royal Alexandra Hospital (RAH), Edmonton, and Foothills Medical Center (FMC), Calgary, was carried out. Cases were detected by reviewing microbiology laboratory records. There were 202 cases in all (UAH 104, FMC 70, RAH 28). For the five study years the candidemia rate was 4.5/10 000 discharges (UAH 7.6, FMC 4.9, and RAH 1.7; P < 0.05 for all interhospital comparisons). The rate remained stable between 1992 and 1995 but rose dramatically in 1996 to 7.6/10 000 (P < 0.01 compared to 1995) as a result of increases at UAH and RAH. Of the 208 species identified, Candida albicans accounted for 135 (65%). During hospitalization 93 (46%) patients died. Species did not influence outcome. Antifungal treatment with fluconazole alone was given to 14% of patients, and increased in frequency throughout the study. No antifungal therapy was given to 47 patients (23%). This group had a much higher mortality (68%) than those who received treatment (39% P < 0.01). Twenty of the untreated patients had already died by the time the blood culture had been reported as growing a yeast. Candidemia rates vary significantly between hospitals and increased in some but not all over the five study years. As many patients with candidemia will have died by the time laboratory diagnosis is made, presumptive antifungal therapy in high-risk patients may be necessary if outcome is to be improved.