Intravaginal impedance and sexual behavior of ovariectomized goats given estrogen alone or in combination with progesterone.

Intravaginal impedance (IVI) fluctuates during the goat estrous cycle. To understand which ovarian steroids are responsible for IVI changes and whether IVI variations are associated with precopulatory and copulatory behaviors, 8 ovariectomized females were assigned to 4 treatments in a 4 x 4 Latin square replicated over four 8-d periods. The treatments were as follows: progesterone plus estradiol-17beta (P4 + E2), oil plus estradiol-17beta (E2), progesterone plus oil (P4), or oil (OIL). Daily IVI measurements at the vagino-cervical junction were taken at 1 and 70 KHz. Progesterone was given on d 2 and 3. Estradiol was given in the evening of d 5. On d 1 to 8, goats were group-exposed to a sexually experienced male and observed for the expression of sexual behaviors. On d 6 and 7, IVI was less when goats received P4 + E2 or E2 compared with goats given P4 or OIL (P < 0.05). Impedance measured at 1 kHz tended to remain lower on d 8 in P4 + E2-treated females compared with those given P4 or OIL (P < 0.055). Like previous results, P4 + E2 or E2 treatment induced behavioral estrus; 5 of 8 P4 + E2-treated and 5 of 8 E2-treated females were sexually receptive on d 6. On d 7, although IVI remained low and 2 of 8 P4 + E2-treated goats and 4 of 8 E2-treated goats remained sexually receptive, no additional females were in estrus. No IVI decreases and no estrous behavior were observed in goats given P4 or OIL. This experiment demonstrated that E2 initiates the periestrous drop in IVI, and P4 may delay baseline return.

Transport of resistance-inducing sterols in phloem sap of barley.

After root application of [7alpha-3H]-7beta-hydroxysitosterol and [3alpha,6beta-3H2]-6alpha-hydroxylathosterol these sterols could be detected in the leaves and phloem sap feeding aphids. These results imply that the phloem sap is a sterol transport system in barley plants.

Factors Affecting the Transmission and Spread of Sugarcane yellow leaf virus.

Sugarcane, Saccharum spp. hybrid, is widely infected in the United States and many other countries with a yellowing and stunting disease called sugarcane yellow leaf syndrome. The causal agent, Sugarcane yellow leaf virus (ScYLV), is a Polerovirus of the Luteoviridae family. In this study, it was transmitted by the sugarcane aphid, Melanaphis sacchari, and also by the corn leaf aphid, Rhopalosiphum maidis, and the rice root aphid, R. rufiabdominalis. Two other aphids that infest sugarcane in Hawaii did not transmit the virus. Some Hawaiian sugarcane cultivars are susceptible to ScYLV, while others remain virus-free in the field. The latter were not infected when inoculated with viruliferous M. sacchari. Virus-free plants of susceptible cultivars were produced through apical meristem culture and were readily reinfected by viruliferous M. sacchari. They were also quickly reinfected when planted in a field in proximity to other infected sugarcane naturally infested with M. sacchari. Sugarcane cultivars are hybrids of several Saccharum species. In a field-grown collection of Saccharum and related species, 11 to 71% of the clones of four of the species were infected with ScYLV. None of the related genus Erianthus plants were infected, but four clones were infected experimentally by aphid inoculation. A low to moderate percentage of corn, rice, and sorghum seedlings became infected when inoculated with ScYLV, but barley, oats, and wheat proved to be very susceptible. None of seven weeds common in sugarcane fields were infected with ScYLV.

Psoriasis patients have T-cells with reduced responsiveness to common mycobacterial antigens.

Heparinised blood samples were obtained from 20 patients with chronic plaque psoriasis and from 13 age-matched healthy controls. After preliminary titration, mononuclear cells separated over Ficoll-Tryoson were cultured for 5 days with 10 microg ml(-1) of 15 mycobacterial preparations, or with pokeweed mitogen and concanavalin A. Stimulation indices were determined for each reagent and means were determined for patients and controls. Results for patients showed a striking reduction of responsiveness to mycobacteria, apparently due to loss of responses to group i, common mycobacterial antigens, and no differences in responses to mitogens. These observations relate psoriasis to certain other diseases, notably mycobacterial infections, rheumatoid arthritis, Chagas' disease and human immunodeficiency virus infection. The observations may be relevant to the aetiology of psoriasis, and to potential immunotherapy for the disease.

Immunotherapy with Mycobacterium vaccae in the treatment of psoriasis.

A placebo-controlled study of immunotherapy with Mycobacterium vaccae for chronic plaque psoriasis showed improvement in the psoriasis area severity index in 19 of 21 immunotherapy recipients (P<0.005). Minor improvement, not reaching statistical significance for the group, occurred in nine of 14 placebo recipients. There were losses to follow-up and the placebo used, tetanus toxoid, was not ideal. Clinical improvement after immunotherapy persisted for 6 months and another injection of the immunotherapeutic given to a few volunteers from either group resulted in benefits lasting a year. Lymphoproliferative tests were carried out at each clinic visit, and on 50 matched controls. Starting with reduced responses to mycobacterial antigens and concanavalin A, both treatment groups showed a fall after 3 months, and diverged at 6 months with M. vaccae recipients rising to values similar to those of healthy controls, whereas placebo recipients continued to fall. Conclusions reached were that immunotherapy with M. vaccae gave long-lasting clinical benefit to most patients, with minimal side effects. This accompanied a return towards normal cellular immune responsiveness to mycobacterial antigens, which did not follow the use of the placebo.

Increased weight gain and effects on production parameters of Holstein heifer calves that were allowed to suckle from birth to six weeks of age.

Forty Holstein heifer calves were assigned to two treatments. Control calves (n = 20) were fed milk replacer in open buckets, and calves that were allowed to suckle (n = 20) were paired and suckled the same dam three times daily. Treatments were conducted during the first 6 wk following birth; thereafter, all calves received the same management, and weaning was at 60 d of age. During treatment, calves that were allowed to suckle had significantly higher average daily gains than did control calves. However, at 12 wk of age, calves that were allowed to suckle had significantly lower body weights (BW) than did control calves. Age at conception was significantly lower, and BW at conception and conception rate tended to be higher, for calves that were allowed to suckle. Calving age was significantly earlier for heifers that had been allowed to suckle as calves, and BW at calving also tended to be higher. Height at the withers after calving was also significantly higher for those heifers. Milk production during first lactation tended to be higher for the heifers that had been allowed to suckle as calves. Our results indicated that heifer calves that suckled milk during the first 42 d of age had higher average daily gains, higher height at the withers, an earlier age at calving, and a tendency for greater milk production than did calves fed milk replacer.

Relationship between frequent milking or suckling in early lactation and milk production of high producing dairy cows.

Groups of 9 or 10 cows were assigned to one of three treatments 1) machine-milking three times daily, 2) machine-milking six times daily, and 3) suckling three times daily in addition to machine- milking three times daily. Treatments were conducted during the first 6 wk postpartum; thereafter, all cows were milked three times daily. During treatment, milk production was highest for suckled cows and lowest for cows milked three times daily. The DMI were similar for suckled cows and cows milked three times daily but higher for those milked six times daily. Body weight loss was greatest for suckled cows and least for cows milked three times daily. During wk 7 to 18 postpartum, cows milked six times daily exhibited a carry-over effect on milk production that was greater than that of other groups, During treatment, plasma growth hormone and IGF-I concentrations were elevated for suckled cows and, to a lesser extent, for cows milked six times daily. Prolactin and oxytocin similarly increased, but insulin decreased in suckled cows and, to a lesser extent, in cows milked six times daily. Posttreatment differences persisted for insulin and IGF-I, but not for the other hormones. Increased frequency of udder emptying increased milk production, and suckling was superior to machine-milking. High milk production was associated with elevated growth hormone, IGF-I, prolactin, and oxytocin, although cause and effect could not be established. The failure of suckled cows to increase feed intake to match output requires further investigation.

Altered calcium-binding ability of plasma proteins as the cause of hypocalcemia in lepromatous leprosy.

This paper reports a study performed on 10 lepromatous leprosy outpatients and on the same number of age- and sex-matched contacts. All of the lepromatous patients were hypocalcemic, but plasma levels of ionized calcium and the acid-base status were normal. The average daily food intake assessed through a questionnaire revealed adequate nutrition of patients and controls. Plasma proteins and 1,25-dihydroxyvitamin D3 and intestinal absorption of calcium were discarded as the causes of the hypocalcemia. In vitro experiments designed to investigate the effect of hydrogen ion concentration on the equilibrium between calcium ion and proteins revealed that, at normal pH values, plasma proteins from lepromatous leprosy patients bind a smaller fraction of total plasma calcium than those from controls. This phenomenon produces a normal concentration of ionized calcium that determines a normal parathyroid status as indicated by the normal urinary excretion of hydroxyproline and plasma concentrations of alkaline phosphatase (total and bone isoenzyme) and tartrate-resistant acid phosphatase.

Reticulohistiocitosis multicéntrica / Multicenter reticulohistiocytosis

Se comunica un caso de reticulohistiocitosis multicéntrica en una mujer que inició su enfermedad con astenia y manifestaciones articulares, instalando luego lesiones en piel cuya biopsia estableció el diagnóstico. Los análisis de laboratorio fueron normales incluyendo perfil lipídico, función tiroidea e inmunológico. Ante el fracaso del tratamiento con aspirina y otros antiinflamatorios se instituyó corticoideoterapia a dosis inmunosupresoras, con rápida y excelente respuesta. Dado que no existen alteraciones inmunológicas demostradas en la R.H.M., los autores proponen que los corticoides podrían haber actuado por su efecto antiinflamatorio y sugieren usar en nuevos casos dosis menores (antiinflamatorias) de corticoides (AU)

Reticulohistiocitosis multicéntrica / Multicenter reticulohistiocytosis

Se comunica un caso de reticulohistiocitosis multicéntrica en una mujer que inició su enfermedad con astenia y manifestaciones articulares, instalando luego lesiones en piel cuya biopsia estableció el diagnóstico. Los análisis de laboratorio fueron normales incluyendo perfil lipídico, función tiroidea e inmunológico. Ante el fracaso del tratamiento con aspirina y otros antiinflamatorios se instituyó corticoideoterapia a dosis inmunosupresoras, con rápida y excelente respuesta. Dado que no existen alteraciones inmunológicas demostradas en la R.H.M., los autores proponen que los corticoides podrían haber actuado por su efecto antiinflamatorio y sugieren usar en nuevos casos dosis menores (antiinflamatorias) de corticoides

Androstenedione, dehydroepiandrosterone and testosterone in ovarian vein plasma and androstenedione in peripheral arterial plasma during the bovine oestrous cycle.

Catheters were placed in the carotid artery via a facial artery (n = 12) and in the ovarian vein (n = 12), and, in conjunction, electromagnetic flow meters were placed around the ovarian artery (n = 6) in cyclic beef cows. Androstenedione was quantitatively the highest and dehydroepiandrosterone the lowest of the ovarian androgens measured. Ovarian androgens were correlated positively with each other (P less than 0.05) but not with ovarian blood flow or day of the cycle. There was a trend for spikes of androgen release (ovarian vein concentration x ovarian blood flow) from the ovary to be greatest during the period of decreasing progesterone and CL regression. However, only with testosterone were spikes of release different (Days--13 to--9 less than Days -8 to -4; P less than 0.05; Day 0 = oestrus). The dynamic changes in ovarian androgens noted in this study were compatible with the concept of continuous follicular development and atresia throughout the oestrous cycle.