Incompatibility on brassica stigmas is overcome by treating pollen with cycloheximide.

Pollen of Brassica exhibited strong self-incompatibility. It did not germinate on, adhere to, or extend into the stigmatic tissues of the female parent plant. In contrast, pollen that had been treated with cycloheximide germinated on and penetrated into self-stigmas to the same degree as untreated pollen placed on crossstigmas (compatible). Germ tubes from cycloheximide-treated pollen did not continue growth through stylar tissues and therefore were unable to effect fertilization.

Sexual function in 1,202 aging males: differentiating aspects.

BACKGROUND: Late-life sexuality is an important quality-of-life issue that has been minimally explored. This survey seeks to extend our knowledge of the relationship of sexual attitudes and preferences to sexual functioning of a large group of older, community-dwelling men. METHODS: Older men aged 58-94 (N = 1,202) were surveyed with an anonymous self-administered questionnaire including 63 items regarding present and past, actual and desired sexual practices and attitudes. RESULTS: Although age correlated consistently with increased erectile dysfunction and decreased sexual activity, a substantial number of older men continued active sexual behaviors supported by positive attitudes toward sexual function. It was found that both health status and perceived partner's responsiveness are prominent moderators of the age effect. CONCLUSION: In the absence of social isolation and health issues, many older men show persistently active sexual lifestyles as evidenced in their interest and participation in sexual activities. These findings negate a portion of the starkly negative imagery of sexual expression in aging males.

Randomized comparison of general and regional anesthesia for cesarean delivery in pregnancies complicated by severe preeclampsia.

OBJECTIVE: To evaluate the maternal and fetal effects of three anesthetic methods used randomly in women with severe preeclampsia who required cesarean delivery. METHODS: Eighty women with severe preeclampsia, who were to be delivered by cesarean, were randomized to general (26 women), epidural (27), or combined spinal-epidural (27) anesthesia. The mean preoperative blood pressure (BP) was approximately 170/110 mmHg, and all women had proteinuria. Anesthetic and obstetric management included antihypertensive drug therapy and limited intravenous (IV) fluid and drug therapy. RESULTS: The mean gestational age at delivery was 34.8 weeks. All infants were born in good condition as assessed by Apgar scores and umbilical arterial blood gas determinations. Maternal hypotension resulting from regional anesthesia was managed without excessive IV fluid administration. Similarly, maternal BP was managed without severe hypertensive effects in women undergoing general anesthesia. There were no serious maternal or fetal complications attributable to any of the three anesthetic methods. CONCLUSION: General as well as regional anesthetic methods are equally acceptable for cesarean delivery in pregnancies complicated by severe preeclampsia if steps are taken to ensure a careful approach to either method.

Reducing crying and irritability in neonates using a continuously controlled early environment.

A mother's "holding" environment has been shown to be effective in reducing infant crying and irritability. When mothers hold or cuddle their infants they create a microenvironment with stimuli similar to those of the intrauterine environment. Several of these same stimuli were incorporated into a cradle designed to provide a similar "holding" environment for the infant when the mother was not there. Ninety healthy term newborn infants were randomized to an experimental (n = 45) or control group (n = 45). The experimental group used a cradle that produced motion, sound, tactile (containment), and reduced-light stimuli at stimulus levels that initially approximated intrauterine sensory stimulation levels and gradually decreased to the levels of the home environment over 16 weeks. The control group used an identical cradle with no stimulus modulation features. Infants were placed in their respective cradles from 2 hours after birth during the times they would normally be placed in an infant bed. The mother-infant interaction or parenting style was not changed or manipulated. Mothers' use of the cradles did not differ significantly. An electronic status monitor measured and recorded infant presence and crying in the cradles. The Brazelton Neonatal Behavioral Assessment Scale test was done at 1 to 2, 14, and 24 days of age by "blinded" examiners. Additionally, phone calls and home visits were conducted by a registered nurse.(ABSTRACT TRUNCATED AT 250 WORDS)

A modified newborn intensive care unit environment may shorten hospital stay.

Premature infants with birth weights from 1121 to 2000 gm were assigned randomly to two groups. Experimental group infants were placed on a microprocessor-controlled cradle that provided levels of motion and sound analogous to those of the third-trimester intrauterine environment. Periods of motion totaling 50% of the time were randomized on and off; motion speed was reduced 35% during a 12-hour night period. A uterine souffle sound was generated continuously but varied in pulse rate and volume with the motion and speed of the bed. Experimental group infants (n = 20) were placed on the cradle under a radiant warmer as soon as their condition was stable clinically. Control group infants (n = 18) were usually placed initially under a radiant warmer and transferred to an incubator when their condition was stable. Otherwise, both groups received standard newborn intensive care unit care. The mean length of hospital stay was significantly shorter for experimental group infants than for control group infants after controlling for gestational age and weight on entry to the study. Experimental group infants began nippling earlier and stopped requiring gavage feedings sooner. Experimental group infants had a decreased incidence of apnea. Blinded Brazelton Neonatal Behavioral Assessment Scale scores for the Orientation and Range of State cluster scales were significantly better for experimental group infants. A retrospective contrast group of preterm infants who met study criteria had an average length of stay similar to that of the control group infants. These data support the hypothesis that appropriate levels and kinds of stimulation may facilitate the maturation of preterm infants.

Effect of ivermectin delivered from a sustained-release bolus on the productivity of beef cattle in Oregon.

The effect of ivermectin delivered from a sustained-release bolus (I-SRB) on the weight gain of beef cattle through a grazing season was evaluated using 20 yearling beef steer calves randomly divided into two groups of ten animals each. Calves in the control group each received a placebo bolus, while those in the treatment group each received an I-SRB designed to release 12 mg ivermectin day-1 for approximately 90 days. All animals were weighted and samples of feces were collected from the rectum at monthly intervals, beginning on Day 0, until trial termination (Day 148). Pasture larval counts were also conducted on herbage collected on each sampling date. On Day 119, two control and two treated calves were removed from pasture, housed in isolation for 3 weeks, then necropsied for recovery of gastrointestinal nematodes. Three sets of parasite-naive tracer calves were utilized to evaluate the initial, interim and final levels of pasture contamination by nematode larvae. A fourth set was used to evaluate the level of pasture contamination the following spring. The use of the I-SRB resulted in a greater than 99% reduction in fecal egg counts of trichostrongyles and numbers of gastrointestinal nematodes in the treated principals, as well as an average daily gain advantage of 0.114 kg over the 148 day period. A 67-98% reduction in pasture larval nematode contamination occurred on pastures grazed by the treated animals, as indicated by the parasite burden in tracer calves and pasture larval counts. The treatment effect was eventually lost by the following spring since tracer calves on the treated pasture had only 33% fewer nematodes than those on the control pasture.

Clinical experience with open laparoscopy.

A modified method of open laparoscopy was performed on 568 consecutive patients requiring laparoscopy or laparoscopic surgery. There were no intraoperative complications related to the technique. All patients were reviewed at 1 week following surgery; 4% had minor umbilical sepsis, while none had a postoperative hernia. The modifications to the technique of open laparoscopy described here make it simple and efficient while maintaining the safety inherent with this technique.

Efficacy of ivermectin administered via sustained-release bolus against gastrointestinal nematodes in cattle.

Twelve calves (mean weight, 175.5 kg) were used to confirm efficacy of ivermectin delivered from a prototype sustained-release bolus against naturally acquired gastrointestinal nematodes including early fourth-stage (inhibited) larvae of Ostertagia ostertagi. The calves were allocated by restricted randomization on weight to 1 of 2 groups: controls, to which a placebo bolus was given orally, and treated calves, to which a sustained-release bolus designed to deliver 8 mg of ivermectin/day at a steady rate was given orally. After treatment, the 2 groups were housed in separate pens with concrete flooring. Twenty-eight days after treatment, all calves were euthanatized and necropsied. The ivermectin-treated calves had no larval or adult Ostertagia spp and significantly (P less than 0.01) fewer adult Trichostrongylus axei and adult Cooperia (C oncophora, C punctata and C surnabada) than control calves. Efficacy of ivermectin was greater than 99% for Cooperia spp, and 100% for other parasites. Drug-related adverse reactions were not observed.

Efficacy of clorsulon against mature, naturally acquired Fasciola hepatica infections in cattle and sheep.

Clorsulon (3.5 or 7 mg/kg of body weight) was given orally to mature cows (dairy or beef) and to mature mixed-breed sheep harboring patent infections of Fasciola hepatica. Eighteen animals of each species were assigned to a control group (drug vehicle) or to 1 of 2 treatment (3.5 or 7.0 mg/kg) groups of 6 animals each. On posttreatment days 8 (cows) or 14 (sheep), the animals were slaughtered for recovery of flukes. In cows, the efficacy (P values for treatment groups vs control) of clorsulon against infections of mature F hepatica was 99.21% (P less than or equal to 0.0065) at 3.5 mg/kg and was 100% (P less than or equal to 0.0039) at 7 mg/kg. In sheep, the efficacy was 93.33% (P less than or equal to 0.0104) at 3.5 mg/kg and was 100% (P less than or equal to 0.0039) at 7 mg/kg. These results indicate that clorsulon is a highly effective compound for the treatment of mature F hepatica in cows and sheep.

Efficacy of an in-feed ivermectin formulation against gastrointestinal helminths, lungworms, and sarcoptic mites in swine.

The efficacy of ivermectin as an in-feed formulation was evaluated against naturally acquired gastrointestinal helminths, lungworms, and sarcoptic mites (experiment 1; n = 24) and against induced infection with intestinal nematodes (experiment 2; n = 24) in pigs. Treatments consisted of ivermectin administered in feed at concentrations calculated to provide 100 or 200 micrograms/kg of body weight/d for 7 days or of nonmedicated feed (controls) for 7 days. At concentration of 100 micrograms of ivermectin/kg/d, efficacy against naturally acquired infections was 97.7% for Ascaris suum, 97.8% for Metastrongylus spp, greater than 99% for Oesophagostomum spp, 100% for Macracanthorhynchus hirudinaceus, and 89.7% for Ascarops strongylina. Against induced infections (fourth-stage larvae), efficacy was 100% for A suum and 96.9% for Oesophagostomum spp. At concentration of 200 micrograms of ivermectin/kg/d, efficacy against naturally acquired infections was 100% for A suum, Hyostrongylus rubidus, Metastrongylus spp, and Ascarops strongylina; greater than 99% for Oesophagostomum spp; and 85.9% for Macracanthorhynchus hirudinaceus. Against induced infections (fourth-stage larvae), efficacy was 100% for A suum and 95% for Oesophagostomum spp. At concentrations of 100 and 200 micrograms of ivermectin/kg/d, efficacy against Sarcoptes scabiei var suis was evidenced by elimination of the mite by posttreatment day 14.

Efficacy of ivermectin and pyrantel pamoate combined in a chewable formulation against heartworm, hookworm, and ascarid infections in dogs.

Eight trials were conducted in dogs to document the efficacy of ivermectin (6 micrograms/kg of body weight) and pyrantel pamoate (5 mg of active pyrantel/kg) in a beef-based chewable formulation against Dirofilaria immitis, Ancylostoma caninum, Uncinaria stenocephala, Toxocara canis, and Toxascaris leonina. Three studies involved induced infection with D immitis, and 5 studies involved induced or natural infection with hookworms and ascarids. In 3 intestinal parasite trials, the efficacy of the combination chewable tablet was compared with each of its components. Results indicated that 1 component did not interfere with the activity of the other. In 1 heartworm and 2 intestinal parasite trials, the efficacy of pyrantel, ivermectin/pyrantel combination, or ivermectin with pyrantel dosage of 10 mg/kg was evaluated. The ivermectin/pyrantel combination was 100% effective in preventing development of D immitis larvae. Efficacy of the combined product against T canis, Toxascaris leonina, A caninum, and U stenocephala was 90.1, 99.2, 98.5, and 98.7%, respectively. In the intestinal parasite trials, each individual component was found not to interfere with the anthelmintic action of the other. Increasing the dosage of pyrantel to 10 mg/kg (2 x that in the combination) did not interfere with the efficacy of ivermectin against heartworm or increase the activity of pyrantel against intestinal parasites.

Efficacy of ivermectin against the mange mite Sarcoptes scabiei var suis in pigs.

The efficacy of ivermectin administered by esophageal intubation in a single dose was evaluated against the mange mite Sarcoptes scabiei var suis in 24 naturally infested pigs. Six pigs were allocated to each of the 4 treatment groups. Control (group 1) pigs were given nonmedicated water, group 2 were given ivermectin at 300 micrograms/kg of body weight, group 3 were given ivermectin at 400 micrograms/kg, and group 4 were given ivermectin at 500 micrograms/kg. The pigs were examined for S scabiei before treatment and on days 7, 14, 21, and 28 after treatment. Of the 18 ivermectin-treated pigs, 10 had no live S scabiei recovered on day 7 after treatment, 16 had none on day 14, 18 had none on day 21, and 16 had none on day 28. All 6 nonmedicated control pigs had live S scabiei recovered on days 7 and 21, and 5 control pigs had mites on days 14 and 28. The single administration of ivermectin given by esophageal intubation was highly effective in reducing the number of S scabiei at all dose levels tested. The pooled ivermectin-treated groups had significantly (P less than 0.01) fewer mites than the control group on all posttreatment examination days. There were no statistically significant differences among the ivermectin dose levels.

Efficacy of ivermectin in a topical formulation against induced gastrointestinal and pulmonary nematode infections, and naturally acquired grubs and lice in cattle.

Efficacy of ivermectin in a topical formulation was evaluated in cattle against adult gastrointestinal and pulmonary nematode infections (experiment 1, n = 24), the 2nd- and 3rd-stage larvae of Hypoderma spp (experiment 2, n = 12), and the biting louse Damalinia bovis (experiment 3, n = 12). Nematode infections were induced and grubs and lice were naturally acquired. Treatments consisted of a single dose of ivermectin in a topical formulation of 200, 500, or 1,000 micrograms/kg of body weight in experiment 1 or 500 micrograms/kg in experiments 2 and 3. At 1,000 micrograms/kg, ivermectin was 100% effective against Ostertagia ostertagi, Trichostrongylus colubriformis, Oesophagostomum radiatum, Nematodirus helvetianus, Haemonchus placei, and Dictyocaulus viviparus and was greater than 99% effective against Cooperia oncophora, C punctata, and T axei. At 500 micrograms/kg, the efficacy was 100% against C oncophora, C punctata, O ostertagi, T axei, Oes radiatum, N helvetianus, Haem placei, and Dict viviparus and greater than 99% against T colubriformis. At 200 micrograms/kg, the efficacy was 100% against Oes radiatum, Haem placei, and Dict viviparus, greater than 99% for O ostertagi, 96% for C oncophora, 86% for C punctata, 90% for T axei, 85% for T colubriformis, and 71% for N helvetianus. At 500 micrograms/kg, ivermectin was highly effective against the grubs Hypoderma bovis and H lineatum and eliminated the louse Damalinia bovis.

Efficacy of ivermectin chewable tablets and two new ivermectin tablet formulations against Dirofilaria immitis larvae in dogs.

One hundred four heartworm-free Beagles less than 1 year old were studied to determine the efficacy of ivermectin chewable tablets and of 2 other ivermectin tablet formulations against heartworm larvae. At 30 days after SC inoculation of dogs with infective Dirofilaria immitis larvae, all ivermectin formulations were given orally at dosage of 6 micrograms/kg of body weight. The ivermectin chewable tablets also were given orally at dosage of 2 and 6 micrograms/kg at 30 and 45 days, respectively, after injection of larvae. Replicates of 6 or 8 dogs in each study were formed on the basis of gender and body weight and, within replicates, were randomly allocated to treatment groups. At 30 days after injection of larvae, the additional dogs (in replicates of 8) were assigned to the control group and to the group given ivermectin chewable tablets at dosage of 6 micrograms/kg. All dogs were housed individually. Necropsy was performed approximately 5 or 6 months after larvae were administered. In both trials, all control dogs had heartworms at necropsy (University of Illinois--geometric mean, 35.0; Florida--geometric mean, 26.1). In both trials, the ivermectin chewable tablet (6 micrograms/kg) and both tablet formulations (6 micrograms/kg) given at 30 days after larval injection, and the chewable formulation (6 micrograms/kg) given at 45 days after larval injection were 100% effective (P less than 0.01) in preventing development of induced infection with D immitis.(ABSTRACT TRUNCATED AT 250 WORDS)

Efficacy of an in-feed formulation of ivermectin against somatic larvae of Strongyloides ransomi in pregnant swine.

OBJECTIVE: To confirm that ivermectin fed for 7 days to pregnant sows controls transmission of Strongyloides ransomi larvae to pigs via the colostrum or milk. ANIMALS: 24 mixed-breed sows. PROCEDURE: The sows were infected with 250,000 S ransomi larvae on 3 occasions (days 63, 64, or 65, days 71 or 73, and days 78, 79, or 80 of gestation). Eight sows received ivermectin at a dosage of 100 micrograms of ivermectin/kg of body weight/d from days 92 to 99 of gestation, and 8 sows were treated from days 103 to 110 of gestation; 8 remaining sows received unmedicated vehicle. Numbers of S ransomi larvae were counted in samples of colostrum or milk collected 1, 2, and 7 days after parturition. At 7 and 14 days after parturition, fecal samples were collected from each sow and from 4 pigs from each litter for determination of nematode egg counts; at the latter date, pigs were euthanatized and necropsied for worm counting. RESULTS: Pigs born to ivermectin-treated sows had significantly (P < 0.01) fewer adult S ransomi than did those born to control sows; efficacy was 100%. Treated sows had significantly (P < 0.05) fewer S ransomi larvae in colostrum/milk samples taken 1, 2, and 7 days after parturition than did control sows; efficacy was 100%, with the exception of 1 S ransomi larva found in a milk sample from 1 treated sow at 2 days after parturition. CONCLUSION AND CLINICAL RELEVANCE: Ivermectin fed to sows during the last third of gestation at a dosage of 100 micrograms/kg/d for 7 consecutive days is highly efficacious for control of transmission of infective S ransomi larvae to pigs via colostrum or milk.

Prophylactic efficacy of an ivermectin sustained-release bolus against challenge exposure with gastrointestinal and pulmonary nematode infective larvae in calves.

Twelve Holstein calves were used to determine the prophylactic efficacy of ivermectin against challenge exposure with gastrointestinal and pulmonary nematodes. Two groups of 6 calves (mean body weight, 205 kg) each were formed by restricted randomization according to body weight. Group-1 calves served as nonmedicated controls. Each calf of group 2 was orally given one prototype sustained-release bolus designed to deliver ivermectin at a continuous daily dose of 8 mg. Third-stage nematode infective larvae were given to the calves on posttreatment days 28 and 42. The calves were euthanatized 77 or 78 days after treatment. Ivermectin was 100% effective (P less than 0.05) in preventing the establishment of infection by Haemonchus placei, Ostertagia ostertagi, Cooperia spp (C punctata, C oncophora, C surnabada), Nematodirus helvetianus, Oesophagostomum radiatum, and Dictyocaulus viviparus and was greater than 99% effective against Trichostrongylus axei. Incidental infection by Trichuris spp was reduced by 94% (P = 0.08).

Efficacy of ivermectin in oral paste formulation against immature gastrointestinal and pulmonary nematodes in cattle.

The anthelmintic efficacy of ivermectin in oral paste formulation was evaluated against the 4th-stage larvae of 8 gastrointestinal nematodes and the common lung-worm in 14 experimentally inoculated calves. Two groups consisting of 7 calves each were formed by restricted randomization on body weight. The infective larvae were given orally to the animals on a staggered schedule so that the parasites were in the 4th larval stage when the animals were treated. One group was given vehicle paste, and the other group was treated with ivermectin in oral paste at the dose level of 200 micrograms/kg of body weight. The animals were killed 18 or 19 days after treatment. Ivermectin was 100% effective against Dictyocaulus viviparus, Oesophagostomum radiatum, Haemonchus placei, Ostertagia ostertagi, and Trichostrongylus axei and greater than 99% effective against Cooperia oncophora, C punctata, T colubriformis, and Nematodirus helvetianus.

Potential for cross-transmission of Dictyocaulus viviparus between cattle and white-tailed deer.

Development of an in vitro culture system for infectious Dictyocaulus viviparus larvae made it possible to study the potential cross-transmission of D. viviparus between white-tailed deer (Odocoileus virginianus) and cattle (Bos taurus). Between 26 September 1995-29 February 1996, six parasite-free bull calves were individually inoculated with 15 to 50 infective third stage larvae (L3)/kg of body weight cultured from adult D. viviparus collected from white-tailed deer. Three bull calves were simultaneously inoculated with 45 L3/kg of body weight recovered from cattle either by the Baermann technique or by in vitro culture as above. All three calves inoculated with the homologous cattle strain became patently infected while all six calves inoculated with the heterologous deer strain remained negative for the presence of D. viviparus in the feces and in the lungs upon necropsy.

Assessment of parasite control and weight gain after use of an ivermectin sustained-release bolus in calves.

OBJECTIVE: To assess parasite control and weight gain after administration of an ivermectin sustained-release bolus over 135 days to calves grazing in the midwestern United States. DESIGN: Replicated pasture study. ANIMALS: 56 Bos taurus calves. PROCEDURE: Calves were matched for body weight and randomly allocated to remain untreated or to receive an ivermectin sustained-release bolus before turnout on day 0. Calves were grazed by treatment group on B pastures (4 replicates). Body weights and fecal egg counts were recorded on days- 1 and 28, and then at 28-day intervals until day 168. RESULTS: Parasitism was not clinically evident prior to or during the study. In treated calves, mean fecal egg counts were at or near 0 at all posttreatment evaluations. Although the mean egg count exceeded 20 ova/g only once in control calves, the cumulative egg output was > 42 million/calf. For the treated group, it was < 0.1% of this number. Mean total weight gain was 33.9 kg (74.6 lb) greater for ivermectin-treated calves than for untreated control calves (P < 0.02): a 34% increase. CLINICAL IMPLICATIONS: Fecal trichostrongyle eggs from calves can accumulate over a grazing season to provide enormous potential for augmenting pasture infectivity. An ivermectin sustained-release bolus (administered to calves being placed on pasture) controls parasitism, limits pasture infectivity, and can substantially influence growth by limiting the impact of subclinical parasitism.

Evaluation of the persistence of the effect of ivermectin and abamectin against gastrointestinal and pulmonary nematodes in cattle.

The persistence of the effect of ivermectin and abamectin against gastrointestinal nematodes and lungworm in cattle was evaluated in two trials, each involving 28 animals. Groups of seven cattle either remained untreated, or were treated topically with ivermectin at 500 micrograms/kg bodyweight or subcutaneously with either ivermectin or abamectin at 200 micrograms/kg bodyweight. Starting on the day of treatment the cattle were given daily trickle infections with various infective nematode larvae for two weeks (Haemonchus species, Trichostrongylus axei and Cooperia species), three weeks (Ostertagia ostertagi and Oesophagostomum radiatum) and four weeks (Dictyocaulus viviparus). The cattle were killed 49 to 51 days after treatment and their worm burdens measured. An efficacy of > 99 per cent was recorded in all the groups demonstrating that the products controlled Haemonchus species, T axei, C oncophora, C punctata and C surnabada for at least two weeks, O ostertagi and O radiatum for at least three weeks and D viviparus for at least four weeks.