According to Bateman's principle, female fecundity is limited relative to males, setting the expectation that males should be promiscuous, while females should be choosy and select fewer mates. ...However, several surfperches (Embiotocidae) exhibit multiple paternity within broods indicating that females mate with multiple males throughout the mating season. Previous studies found no correlation between mating success and reproductive success (i.e., a Bateman gradient). However, by including samples from a broader range of reproductive size classes, we found evidence of a Bateman gradient in two surfperch species from distinct embiotocid clades. Using microsatellite analyses, we found that 100% of the spotfin surfperch families sampled exhibit multiple paternity (Hyperprosopon anale, the basal taxon from the only clade that has not previously been investigated) indicating that this tactic is a shared reproductive strategy among surfperches. Further, we detected evidence for a Bateman gradient in H. anale; however, this result was not significant after correction for biases. Similarly, we found evidence for multiple paternity in 83% of the shiner surfperch families (Cymatogaster aggregata) sampled. When we combine these data with a previous study on the same species, representing a larger range of reproductive size classes and associated brood sizes, we detect a Bateman gradient in shiner surfperch for the first time that remains significant after several conservative tests for bias correction. These results indicate that sexual selection is likely complex in this system, with the potential for conflicting optima between sexes, and imply a positive shift in fertility (i.e., increasing number) and reproductive tactic with respect to the mating system and number of sires throughout the reproductive life history of females. We argue that the complex reproductive natural history of surfperches is characterized by several traits that may be associated with cryptic female choice, including protracted oogenesis, uterine sac complexity, and sperm storage.
Surfperch are a unique group of nearshore fishes that give live birth and have been shown to exhibit multiple paternity. For the first time, we show that the basal taxon of surfperch exhibit multiple paternity, using microsatellite analysis, suggesting that this is a shared reproductive tactic among the Embiotocidae. Furthermore, a correlation between mating success and reproductive success, (i.e. a female bateman gradient) is detected for the first time in surfperches.
The antitumor drug ditercalinium is a rare example of a noncovalent DNA-binding ligand that forms bisintercalation complexes via the major groove of the double helix. Previous structural studies have ...revealed that the two connected pyridocarbazolium chromophores intercalate into DNA with the positively charged bis(ethylpiperidinium) linking chain oriented to the wide groove side of the helix. Although the interaction of ditercalinium with short oligonucleotides containing 4−6 contiguous GC base pairs has been examined in detail by biophysical and theoretical approaches, the sequence preference for ditercalinium binding to long DNA fragments that offer a wide variety of binding sites has been investigated only superficially. Here we have investigated both sequence preferences and possible molecular determinants of selectivity in the binding of ditercalinium to DNA, primarily using methods based upon DNase I footprinting. A range of multisite DNA substrates, including several natural restriction fragments and different PCR-generated fragments containing nonconventional bases (2,6-diaminopurine, inosine, uridine, 5-fluoro- and 5-methylcytosine, 7-deazaguanine, 7-deazaadenine, and N 7-cyanoboranoguanine), have been employed to show that ditercalinium selectively recognizes certain GC-rich sequences in DNA and to identify some of the factors which affect its DNA-binding sequence selectivity. Specifically, the footprinting data have revealed that the 2-amino group on the purines or the 5-methyl group on the pyrimidines is not essential for the formation of ditercalinium−DNA complexes whereas the major groove-oriented N7 of guanine does appear as a key element in the molecular recognition process. The loss of N7 at guanines but not adenines is sufficient to practically abolish sequence-selective binding of ditercalinium to DNA. Thus, as expected for a major groove binding drug, the N7 of guanine is normally required for effective complex formation with GC base pairs, but interestingly the substitution of the N7 with a relatively bulky cyanoborane group does not markedly affect the sequence recognition process. Therefore, the hydrogen bond accepting capability at N7 of guanines is not sufficient to explain the GC-selective drug−DNA association, and the implications of these findings are considered.
Four trials were conducted in which laboratory-reared
Dermacentor variabilis nymphs were exposed to
Ehrlichia canis by feeding on experimentally infected dogs as soon as classical morulae were ...detected in peripheral blood monocytes. After molting 25, 50 or 90 adult tick pairs were permitted to feed on 7
Ehrlichia-naive dogs. Transmission occurred in trials 1 (1/1 dog), 3 (1/1 dog) and 4 (2/2 dogs) but not in trial 2 (0/3 dogs), with 4 of 7 dogs becoming infected. Successful transstadial transmission was demonstrated by detection of morulae in peripheral blood lymphocytes and by seroconversion to
Ehrlichia canis 30 d post-exposure. Incubation periods ranged between 17 and 22 days (mean=19). Clinical signs, typical of ehrlichiosis, included mucopurulent ocular discharge, lymphadenopathy and malaise with accompanying pyrexia, leukopenia and thrombocytopenia. Pyrexia, thrombocytopenia and erythrophagocytosis and vacuolization of the cytoplasm of monocytic cells were observed 1–4 d prior to detection of morulae. This is the first demonstration that a tick other than
Rhipicephalus sanguineus is capable of transstadial transmission of this important pathogen of dogs.
Organic carbon (OC) and elemental carbon (EC) are operationally defined by the analysis methods, and different methods give in different results. The IMPROVE (Interagency Monitoring of Protected ...Visual Environments) and NIOSH (National Institute of Occupational Safety and Health) thermal evolution protocols present different operational definitions. These protocols are applied to 60 ambient and source samples from different environments using the same instrument to quantify differences in implemented protocols on the same instrument. The protocols are equivalent for total carbon sampled on quartz-fiber filters. NIOSH EC was typically less than half of IMPROVE EC. The primary difference is the allocation of carbon evolving at the NIOSH 850°C temperature in a helium atmosphere to the OC rather than EC fraction. Increasing light transmission and reflectance during this temperature step indicate that this fraction should be classified as EC. When this portion of NIOSH OC is added to NIOSH EC, the IMPROVE and NIOSH analyses are in good agreement. The most probable explanation is that mineral oxides in the complex particle mixture on the filter are supplying oxygen to neighboring carbon particles at this high temperature. This has been demonstrated by the principle of the thermal manganese oxidation method that is also commonly used to distinguish OC from EC. For both methods, the optical pyrolysis adjustment to the EC fractions was always higher for transmittance than for reflectance. This is a secondary cause of differences between the two methods, with transmittance resulting in a lower EC loading than reflectance. The difference was most pronounced for very black filters on which neither reflectance nor transmittance accurately detected further blackening due to pyrolysis.
Two dipeptides, each containing a lysyl residue, were disubstituted with chlorambucil (CLB) and 2,6-dimethoxyhydroquinone-3-mercaptoacetic acid (DMQ-MA): DMQ-MA-Lys(CLB)-Gly-NH2 (DM-KCG) and ...DMQ-MA-β-Ala-Lys(CLB)-NH2 (DM-BKC). These peptide−drug conjugates were designed to investigate sequence-specificity of DNA cleavage directed by the proximity effect of the DNA cleavage chromophore (DMQ-MA) situated close to the alkylating agent (CLB) inside a dipeptide moiety. Agarose electrophoresis studies showed that DM-KCG and DM-BKC possess significant DNA nicking activity toward supercoiled DNA whereas CLB and its dipeptide conjugate Boc-Lys(CLB)-Gly-NH2 display little DNA nicking activity. ESR studies of DMQ-MA and DM-KCG both showed five hyperfine signals centered at g = 2.0052 and are assigned to four radical forms at equilibrium, which may give rise to a semiquinone radical responsible for DNA cleavage. Thermal cleavage studies at 90 °C on a 265-mer test DNA fragment showed that besides alkylation and cleavage at G residues, reactions with DM-KCG and DM-BKC show a preference for A residues with the sequence pattern: 5‘-G-(A) n -Pur-3‘ > 5‘-Pyr-(A) n -Pyr-3‘ (where n = 2−4). By contrast, DNA alkylation and cleavage by CLB occurs at most G and A residues with less sequence selectivity than seen with DM-KCG and DM-BKC. Thermal cleavage studies using N7-deazaG and N7-deazaA-substituted DNA showed that strong alkylation and cleavage at A residues by DM-KCG and DM-BKC is usually flanked on the 3‘ side by a G residue whereas strong cleavage at G residues is flanked by at least one purine residue on either the 5‘ or 3‘ side. At 65 °C, it is notable that the preferred DNA cleavage by DM-KCG and DM-BKC at A residues is significantly more marked than for G residues in the 265-mer DNA; the strongest sites of A-specific reaction occur within the sequences 5‘-Pyr-(A) n -Pyr-3‘; 5‘-Pur-(A) n -G-3‘ and 5‘-Pyr-(A) n -G-3‘. In pG4 DNA, cleavage by DM-KCG and DM-BKC is much greater than that by CLB at room temperature and at 65 °C. It was also observed that DM-KCG and DM-BKC cleaved at certain pyrimidine residues: C40, T66, C32, T34, and C36. These cleavages were also sequence selective since the susceptible pyrimidine residues were flanked by two purine residues on both the 5‘ and 3‘ sides or by a guanine residue on the 5‘ side. These findings strongly support the proposal that once the drug molecule is positioned so as to permit alkylation by the CLB moiety, the DMQ-MA moiety is held close to the alkylation site, resulting in markedly enhanced sequence-specific cleavage.
Interest in high-flexion total knee arthroplasty (TKA) prostheses designed to provide better postoperative range of motion (ROM) is widespread. We sought to determine whether changes in surface ...geometry of the tibial polyethylene insert could improve postoperative ROM in a consecutive series of patients undergoing TKA with retention of the posterior cruciate ligament (PCL). Two cohorts with Smith & Nephew (Memphis, Tennessee) Posterior Cruciate-Retaining Genesis II total knee prostheses were compared, 79 knees (65 patients) using standard tibial inserts and 85 knees (72 patients) using high-flexion inserts. The standard insert has a slightly raised posterior lip, whereas the high-flexion insert is recessed downward at the posterior margin to facilitate femoral rollback in flexion and eliminate impingement of the femoral component on the back of the polyethylene during rollback. Mean ROM 1 year postoperatively was 112.0° in patients receiving the standard insert and 119.3° in patients receiving the high-flexion insert. Preoperative ROM was similar in both groups. Flexion improvement in the high-flexion group over the standard insert group was statistically significant (P<.001). Final Knee Society Scores did not differ amongst patients receiving the standard and high-flexion inserts. Our study demonstrates that improved postoperative flexion can be achieved without changing surgical technique, bony cuts, or metallic prosthetic parts. This is the first report that we are aware of that documents improvement in ROM after PCL-retaining TKA through the use of high-flexion inserts.
A recording device called the Electronically Activated Recorder (EAR) is described. The EAR taperecords for 30 sec once every 12 min for 2-4 days. It is lightweight and portable, and it can be worn ...comfortably by participants in their natural environment. The acoustic data samples provide a nonobtrusive record of the language used and settings entered by the participant. Preliminary psychometric findings suggest that the EAR data accurately reflect individuals' natural social, linguistic, and psychological lives. The data presented in this article were collected with a first-generation EAR system based on analog tape recording technology, but a second generation digital EAR is now available.
Crop growth and development is affected by intraspecies competition. This study was conducted to determine whether cotton productivity and profitability could be manipulated through planting ...geometry. The effects of row spacing, planting pattern, and variety on cotton fruit distribution, yield, and net returns were investigated near Bella Mina, AL, on a Decatur silt loam (fine, kaolinitic, thermic Rhodic Paleudults); Jackson, TN, on a Calhoun silt loam (fine‐silty, mixed, active, thermic Typic Glossaqualfs); Starkville, MS, on a Leeper silty clay loam (fine, smectitic, nonacid, thermic Vertic Epiaquepts); and Stoneville, MS, on a Bosket very fine sandy loam (fine‐loamy, mixed, active, thermic Mollic Hapludalfs). For both the 76‐ and 97‐cm row spacing, transitioning from a solid to a 2 × 1 skip row pattern reduced cotton lint yield by 19%. Reduced lint yield in the 2 × 1 skip row pattern was attributed primarily to a 7% decrease in the number of Zone 1 and first‐position bolls. Consequently, planting on a solid rather than skip row pattern increased net returns by 21%. Planting cotton in either 76‐ or 97‐cm rows using a solid rather than skip row pattern likely increases crop productivity and profitability across the US cotton belt.
Core Ideas
Alternative cotton row spacings and patterns may improve net returns due to reduced input costs or greater yield.
Regardless of row spacing, transitioning from a solid to 2 × 1 skip row pattern decreased cotton lint yield by 19%.
Planting on a solid pattern rather than 2 × 1 skip row increased net returns by 21%.
A series of anti-tumor/anti-chelate bispecific antibody formats were developed for pre-targeted radioimmunotherapy. Based on the anti-carcinoembryonic antigen humanized hT84.66-M5A monoclonal ...antibody and the anti-DOTA C8.2.5 scFv antibody fragment, this cognate series of bispecific antibodies were radioiodinated to determine their tumor targeting, biodistribution and pharmacokinetic properties in a mouse xenograft tumor model. The in vivo biodistribution studies showed that all the bispecific antibodies exhibited specific high tumor uptake but the tumor targeting was approximately one-half of the parental anti-CEA mAb due to faster blood clearance. Serum stability and FcRn studies showed no apparent reason for the faster blood clearance. A dual radiolabel biodistribution study revealed that the 111In-DOTA bispecific antibody had increased liver and spleen uptake, not seen for the 125I-version due to metabolism and release of the radioiodine from the cells. These data suggest increased clearance of the antibody fusion formats by the mononuclear phagocyte system. Importantly, a pre-targeted study showed specific tumor uptake of 177Lu-DOTA and a tumor : blood ratio of 199 : 1. This pre-targeted radiotherapeutic and substantial reduction in the radioactive exposure to the bone marrow should enhance the therapeutic potential of RIT.
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