Meiotic drive alters sperm competitive ability in stalk-eyed flies.

Meiotic drive results when sperm carrying a driving chromosome preferentially survive development. Meiotic drive should therefore influence sperm competition because drive males produce fewer sperm than non-drive males. Whether meiotic drive also influences the competitive ability of sperm after ejaculation is unknown. Here we report the results from reciprocal crosses that are designed for estimating the sperm precedence of male stalk-eyed flies (Cyrtodiopsis whitei) with or without X-linked meiotic drive. We find that nearly half of all sex-ratio males, as compared with 14% of non-sex-ratio males, fail to produce young in a reciprocal cross. Furthermore, the proportion of progeny sired by a sex-ratio male in a female jointly inseminated by a non-sex-ratio male was less than expected from the number of sperm transferred. These effects are not due to differential sperm storage by females because, after a single mating with a sex-ratio male, all females stored sperm and because two sex-ratio males share paternity after jointly mating with a female. In addition to demonstrating a new mechanism of sperm competition, these results provide insight into the maintenance of sex-ratio polymorphisms. Sex-ratio males have less than one-half the fertility of non-sex-ratio males, as is required in order for frequency-dependent selection on males to produce a stable sex-ratio polymorphism.

Safe management of dermolipomas.

Most reports on dermolipomas describe the serious complications arising from their removal. The aim of this article was to describe a safe and effective method of removing dermolipomas. Forty-five consecutive eligible patients underwent surgical removal of their dermolipomas over a 20-year period. Of the two complications, only one, a restrictive symblepharon, required further surgery. The techniques for excising simple dermolipomas and dermolipomas associated with a deformity of the lateral canthal angle are described. Safe removal of dermolipomas may be accomplished with minimal resection of the conjunctiva, including the pilosebaceous area, identification of contiguous structures, and removal of only that portion of the dermolipoma anterior to the lateral orbital rim.

Tactual illusions.

16 college males participated in a study exploring active and passive illusions in touch. Analogs to 2 primary and 2 secondary visual illusions were constructed for active and for passive tactual presentation. Tactual illusory effects similar to those one would predict from vision were found in the active mode of presentation of the Müller-Lyer, and horizontal-vertical conditions, while opposite effects were found in the active mode of presentation of a modification of Delboeuf circles and in the passive diamond-square and horizontal-vertical conditions (ps less than .02). Analogous primary and secondary illusory results interacted with the active and passive modes of presentation.

Paying research participants: a study of current practices in Australia.

OBJECTIVE: To examine current research payment practices and to inform development of clearer guidelines for researchers and ethics committees. DESIGN: Exploratory email based questionnaire study of current research participant reimbursement practices. A diverse sample of organisations and individuals were targeted. SETTING: Australia. PARTICIPANTS: Contacts in 84 key research organisations and select electronic listservers across Australia. A total of 100 completed questionnaires were received with representations from a variety of research areas (for example, market, alcohol and drug, medical, pharmaceutical and social research). MAIN MEASUREMENTS: Open-ended and fixed alternative questions about type of research agency; type of research; type of population under study; whether payment is standard; amounts and mechanisms of payment; factors taken into account when deciding on payment practices; and whether payment policies exist. RESULTS: Reimbursement practice is highly variable. Where it occurs (most commonly for drug dependent rather than health professional or general population samples) it is largely monetary and is for time and out-of-pocket expenses. Ethics committees were reported to be often involved in decision making around reimbursement. CONCLUSIONS: Research subject payment practices vary in Australia. Researchers who do provide payments to research participants generally do so without written policy and procedures. Ethics committees have an important role in developing guidelines in this area. Specific guidelines are needed considering existing local policies and procedures; payment models and their application in diverse settings; case study examples of types and levels of reimbursement; applied definitions of incentive and inducement; and the rationale for diverse payment practices in different settings.

The ages of adulthood: a question of numbers.

To examine the number of subjective age categories in the post-high school portion of the American lifecycle, adult respondents, selected on a probability basis in Lafayette-West Lafayette, Indiana, sorted cards describing people in terms of major life events and classified them according to age. A nonlinear decrease in the number of age distinctions occurred in the late portion of middle age (46-65 years). The decrease was explained in terms of the developmental cycle of domestic units and age homogeneity of the kinship network.

Temporal and status dimensions of life cycles.

An alternative approach to the life cycle is developed which avoids the creation of monolithic age categories and exclusive reliance upon the unidimensional index of chronological age. An age status graph is constructed by intersecting age with a status dimension. Using a card sort technique, age norms of status transition for family and work are ascertained. These data exemplify the potential utility of age status graphing in understanding the life cycle. The methodological strengths of operationalizing variables, explicitness of criteria, and conceptual flexibility are discussed.

Inhibition of prostaglandin synthesis by indomethacin augments the renal vasodilator response to bradykinin in the anesthetized dog.

It has been proposed that the increase in renal blood flow (RBF) produced by bradykinin (BK) is mediated or amplified by the intrarenal generation of prostaglandins. The present investigation was designed to explore these relationships further. In anesthetized dogs, the renal arterial infusion of BK (100 ng/kg per min), prior to the intravenous administration of indomethacin, produced a 93 +/- 14% increase in RBF and an increase in the renal venous concentration of a prostaglandin E-like substance ("PGE") from 51 +/- 23 to 235 +/- 73 pg/ml as determined by bioassay. Following indomethacin (5 mg/kg), the same dose of BK produced a 151 +/- 18% increase in RBF (P less than 0.001 compared to the preindomethacin increase) and the concentration of "PGE" remained largely below the threshold of sensitivity of the bioassay system. In three experiments, a highly sensitive and specific radioimmunoassay technique was used to obtain better quantitative estimates of concentrations of E2-like ("PGE2") and F2alpha-like ("PGF2alpha") substances so that determinations of renal efflux could be made. Thus, prior to indomethacin, BK administration increased RBF by 142 +/- 39 ml/min and was associated with a 26-fold increase in renal efflux of "PGE2" and a 12-fold increase in "PGF2alpha." After indomethacin, the effluxes of both "PGE2" and "PGF2alpha" decreased to negligible levels and were not influenced by BK infusion, although RBF increased by 225 +/- 75 ml/min. These results are not compatible with the hypothesis that intrarenal prostaglandins mediate or amplify the renal vasodilator response to BK.

High leg incision fascia lata harvesting.

OBJECTIVE: The traditional method of harvesting fascia lata has been through an incision above the lateral knee. Problems with this method include a conspicuous scar, herniation of the muscle belly, and hematoma formation. The authors describe a new method of harvesting fascia lata in the region of the hip to minimize these complications. DESIGN: Cohort study. PARTICIPANTS: Twenty-three patients underwent harvesting of fascia lata by the technique described by the authors. Twenty-one patients had ptosis with poor levator function. In two patients, the fascia lata was used to wrap a hydroxyapatite implant. INTERVENTION: The technique for harvesting fascia lata through an incision between the greater trochanter and anterior iliac crest is described. Long-term results were collected from chart reviews and patient interviews after surgery. MAIN OUTCOME MEASURES: The patients were evaluated to determine whether any complications resulted from the new incision site. RESULTS: No permanent complications were noted at the incision site. CONCLUSIONS: Fascia lata can be harvested safely in the region of the iliac crest with an inconspicuous scar and with fewer complications than with the more traditional site slightly above the lateral knee.

Anterior ischemic optic neuropathy is not associated with carotid artery atherosclerosis.

BACKGROUND AND PURPOSE: The relation between anterior ischemic optic neuropathy and carotid artery atherosclerotic disease is unclear. We studied patients with anterior ischemic optic neuropathy to determine if they had an increased occurrence of carotid artery stenosis. METHODS: Fifteen consecutive patients with anterior ischemic optic neuropathy were evaluated prospectively for cervical carotid artery stenosis and compared with 30 age- and sex-matched asymptomatic patients and also with 11 age- and sex-matched patients experiencing transient monocular blindness. RESULTS: There was no difference in the mean stenosis of the internal carotid artery between patients with anterior ischemic optic neuropathy (mean carotid stenosis, 19%) and asymptomatic patients (mean carotid stenosis, 9%; p > 0.05), whereas patients with transient monocular blindness had significantly more stenosis (mean, 77%) in the cervical carotid arteries than both control subjects (p < 0.0001) and patients with anterior ischemic optic neuropathy (p < 0.0001). There was also no difference in the percentage of patients with stenosis > or = 30% in anterior ischemic optic neuropathy (two of 15) and asymptomatic patients (five of 30), whereas 10 of 11 patients with transient monocular blindness had stenoses > or = 30%, significantly more than patients with anterior ischemic optic neuropathy (p < 0.0001) and asymptomatic patients (p < 0.0001). CONCLUSIONS: Anterior ischemic optic neuropathy is not a marker for atherosclerotic carotid artery stenosis. The pathogenesis of nonarteritic anterior ischemic optic neuropathy does not involve carotid artery stenosis in most patients.