RESUMEN
Cantharidin, the well-known terpenoid compound from the blood of blister beetles (and active principle of Spanish fly), is a feeding deterrent to insects, effective at a concentration of 10(-5) molar.
Asunto(s)
Hormigas/efectos de los fármacos , Cantaridina/farmacología , Escarabajos , Conducta Alimentaria/efectos de los fármacos , Agresión , Animales , HumanosRESUMEN
The larva of Cassida rubiginosa carries a tight packet of cast skins and feces on a fork held over its back. The packet is a maneuverable shield used by the larva to protect itself against attack. It is highly effective in blocking the bite of ants.
Asunto(s)
Adaptación Biológica , Conducta Animal , Escarabajos/fisiología , Heces , AnimalesRESUMEN
Resting heart rates in 18 species of spiders as determined by a cool laser transillumination technique range from 9 to 125 beats per minute. Cardiac frequencies obtained in this fashion may readily serve as a measure of standard rates of metabolism. A spider's resting heart rate is a function of body size and of foraging energetics.
Asunto(s)
Arañas/fisiología , Animales , Peso Corporal , Metabolismo Energético , Femenino , Frecuencia Cardíaca , Arañas/anatomía & histología , Arañas/metabolismoRESUMEN
The phalangid Vonones sayi has a pair of exocrine defensive glands that secrete quinones (2,3-dimethyl-1,4-benzoquinone and 2,3,5-trimethyl-1,4- benzoquinone). When distributed, the animal emits the secretion, dilutes it with aqueous regurgitated fluid, and effects dosaged delivery of the mixture by brushing it on the assailant with the tips of its forelegs. Predators such as ants are effectively repelled.
RESUMEN
A television camtiera, like the eyes of some insects, is sensitive to ultraviolet light. When equipped with an appropriate ultraviolet-transmitting lens, such a camera can be used for the direct examtiination of ultraviolet reflectiont patterns (for example, on flowers, butterflies) that are invisible to us, but visible to inisects.
RESUMEN
Larvae of the sawfly Neodiprion sertifer (Hymenoptera: Diprionidae), when disturbed, discharge an oily oral effluent essentially identical chemically to the terpenoid resin of its host plant (Pinus sylvestris). The resin is sequestered by the larva upon feeding, and stored in two compressible diverticular pouches of the foregut. The fluid is effectively deterrent to predators. The defensive use by an insect of a plant resin provides an instance of secondary utilization by a herbivore of the protective chemical weaponry of its host.
Asunto(s)
Reacción de Fuga , Insectos/fisiología , Plantas , Resinas de Plantas , Animales , Rickettsiaceae , TerpenosRESUMEN
INTRODUCTION: The latest generations of bisphosphonates constitute a major advance in the management of disorders including Paget's disease, osteoporosis, and osteolytic bone tumors. Recent reports describe numerous cases of osteonecrosis of the jaw in patients treated with bisphosphonates. Some of these reports mention predisposing factors, including surgical procedures, chemotherapy, and radiotherapy. CASES: In the past 12 months, we have observed and treated 9 cases of maxillary osteonecrosis, which we present summarily. DISCUSSION: Some of our cases (3 of 9), like many of those described in literature, do not present predisposing factors. The osteonecrosis may thus be due mainly to the effect of bisphosphonates that, by blocking bone remodeling, may cause excessive bone mineralization. If this hypothesis is confirmed, these cases of osteonecrosis may be due to excess doses. Better dose adjustment should thus help prevent this complication.
Asunto(s)
Conservadores de la Densidad Ósea/efectos adversos , Difosfonatos/efectos adversos , Enfermedades Maxilomandibulares/inducido químicamente , Osteonecrosis/inducido químicamente , Adolescente , Anciano , Anciano de 80 o más Años , Conservadores de la Densidad Ósea/administración & dosificación , Difosfonatos/administración & dosificación , Femenino , Humanos , Imidazoles/administración & dosificación , Imidazoles/efectos adversos , Enfermedades Maxilomandibulares/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Osteonecrosis/diagnóstico por imagen , Pamidronato , Radiografía Panorámica , Cintigrafía , Factores de Tiempo , Tomografía Computarizada por Rayos X , Ácido ZoledrónicoRESUMEN
Widely prescribed, bisphosphonates inhibit bone resorption. They are not metabolised and have long half-lives. Two cases of osteonecrosis of the jaws have recently been attributed to bisphosphonates at the University Hospital of Geneva. The recent literature reveals more than a hundred similar cases throughout the world. Bone exposure appears spontaneously or after dental care. Treatment of the osteonecrosis is controversial and cure very difficult. This pathology is usually seen in patients on chemotherapy, steroids and i.v. bisphosphonates, but is sometimes seen with low-dose p.o. bisphosphonates. In view of the strong association between bisphosphonate therapy and osteonecrosis of the jaw, specialists have recommended dental and oral evaluation during bisphosphonate therapy as well as for several years after drug discontinuation.
Asunto(s)
Difosfonatos/efectos adversos , Maxilares/patología , Osteonecrosis/inducido químicamente , Factores de Edad , Difosfonatos/administración & dosificación , Difosfonatos/uso terapéutico , Interacciones Farmacológicas , Humanos , Infusiones Intravenosas , Esteroides/uso terapéuticoAsunto(s)
Aborto Inducido , Prostaglandinas , Animales , Congresos como Asunto , Femenino , Humanos , EmbarazoRESUMEN
A method for uniformly labeling kilogram amounts of plant litter with 14C is described. Data obtained from field decomposition of tagged fescue litter prepared by this method suggest that 14C flux can be a reliable indicator of energy flow, as measured directly by bomb calorimetry and indirectly by ashfree weight.
RESUMEN
Cantharidin, a potent vesicant and antifeedant, is identified for the first time in two oedemerid beetles from the western hemisphere. Amounts of the substance per beetle were found to range from 2 to 7 µg inHeliocis repanda and from 15 to 35 µg inOxycopis thoracica. Females had two to three times more cantharidin than males of the same species. Cantharidin loads of these beetles are sufficient to irritate human skin.
RESUMEN
Surgical intervention for tarsal tunnel syndrome has been reported since the mid-1960s. In 1975, the authors published their experiences using nerve conduction studies for the diagnosis and follow-up of tarsal tunnel syndrome. Since that time, the authors have operated on approximately 200 cases when conservative care failed to alleviate symptoms to a sufficient degree. In this article, a brief overview of our findings and follow-up is provided.
Asunto(s)
Síndrome del Túnel Tarsiano/cirugía , Estudios de Seguimiento , Pie/inervación , Humanos , Métodos , Neuronas Motoras/fisiología , Conducción Nerviosa/fisiología , Neuronas Aferentes/fisiología , Síndrome del Túnel Tarsiano/diagnóstico , Síndrome del Túnel Tarsiano/fisiopatología , Resultado del TratamientoRESUMEN
OBJECTIVES: Conventional panoramic radiography, a widely used radiographic examination tool in implant treatment planning, allows evaluation of the available bone height before inserting posterior mandibular implants. Image distortion and vertical magnification due to projection geometry is well described for rotational panoramic radiographs. To assess the accuracy of vertical height measurements on direct digital panoramic radiographs, implants and metal balls positioned in the posterior mandible were used as radio-opaque reference objects. The reproducibility of the measuring method was assessed by the inter- and intraobserver agreements. METHODS: Direct digital panoramic radiographs, performed using a Kodak 8000C (Eastman Kodak Company, Rochester, NY), of 17 partially edentulous patients (10 females, 7 males, mean age 65 years) were selected from an X-ray database gathered during routine clinical evaluation of implant sites. Proprietary software and a mouse-driven calliper were used to measure the radiological length of 25 implants and 18 metal reference balls, positioned in mandibular posterior segments. The distortion ratio (DR) was calculated by dividing the radiological implant length by the implant's real length and the radiological ball height by the ball's real height. RESULTS: Mean vertical DR was 0.99 for implants and 0.97 for balls, and was unrelated to mandibular sites, side, age, gender or observer. Inter- and intraobserver agreements were acceptable for both reference objects. CONCLUSIONS: Vertical measurements had acceptable accuracy and reproducibility when a software-based calibrated measurement tool was used, confirming that digital panoramic radiography can be reliably utilized to determine the pre-operative implant length in premolar and molar mandibular segments.
Asunto(s)
Cefalometría/estadística & datos numéricos , Implantes Dentales , Marcadores Fiduciales , Mandíbula/diagnóstico por imagen , Radiografía Dental Digital/estadística & datos numéricos , Radiografía Panorámica/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Aleaciones/química , Cefalometría/normas , Medios de Contraste , Arco Dental/diagnóstico por imagen , Diseño de Prótesis Dental , Femenino , Marcadores Fiduciales/clasificación , Humanos , Arcada Parcialmente Edéntula/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Planificación de Atención al Paciente , Intensificación de Imagen Radiográfica/normas , Radiografía Dental Digital/normas , Radiografía Panorámica/normas , Estándares de Referencia , Reproducibilidad de los Resultados , Programas InformáticosRESUMEN
In a search for group B streptococci, vagina and urethra of 196 pregnant women entering the delivery room were cultured using a selective medium. Sixteen (8.2%) were positive. Fifteen (15%) of 101 nonpregnant women cultured similarly during a clinical consultation were positive. Esogastric aspiration fluid of 199 neonates from the former group of women was also cultured: 8 (4.0%) were positive. Thus, maternal genital colonization was accompanied by neonatal contamination in 7 of 16 cases (43%). Typing of the streptococci revealed identity between all maternal and neonatal isolates tested. These values are comparable with those obtained in other countries. Their epidemiological implications and the prophylaxis and therapy of the neonatal disease are discussed.
Asunto(s)
Esófago/microbiología , Streptococcus agalactiae/aislamiento & purificación , Vagina/microbiología , Ampicilina/uso terapéutico , Femenino , Gentamicinas/uso terapéutico , Humanos , Recién Nacido , Enfermedades del Recién Nacido/prevención & control , Masculino , Embarazo , Infecciones Estreptocócicas/prevención & control , Uretra/microbiologíaRESUMEN
AdultGlomeris marginata reloaded glandular defensive fluid slowly and fairly constantly at 15 °C for 100 days after being milked to depletion. Female millipedes produced more sticky exudate than males, but the two sexes stored secretion at approximately the same absolute rate, 12 µg/individual/day. Hence, males, which weighed one third as much as females, accumulated disproportionately more secretion. MaleGlomeris in the reloading treatments after 75 days yielded as much exudate as controls, millipedes given 100 days to supplement their field reserves, whereas experimental females always produced less secretion than controls. Projections from these data suggest that adultGlomeris, regardless of sex, require more than 4 months to replenish their defensive reserves after completely discharging them in an attack.
RESUMEN
Wolf spiders (Lycosa spp.) show delayed induced sedation (total immobilization) of prolonged duration (in the order of days) after attacks upon millipeds (Glomeris marginata). The sedation is specifically attributable to glomerin and homoglomerin, two previously characterized quinazolinones present in the defensive secretion of Glomeris. Median sedative doses for the quinazolinones are in the range of 1-7 mug per spider, a fraction of the total (60-90 mug) present in the secretion of medium to full-grown millipeds. A sedative effect upon an invertebrate predator has not previously been demonstrated for an animal defense. Quinazolinones include the synthetic drug methaqualone (Quaalude), a potent human sedative.
RESUMEN
Biosynthesis of cantharidin in a blister beetle, Lytta polita, is effectively inhibited by 6-fluoromevalonate. Inhibition is attributed specifically to the fluorine substituent. Biochemical inhibition has not been demonstrated previously for an arthropod's defensive substance.