Domestic queens under natural temperate photoperiod do not manifest seasonal anestrus

Domestic cat seasonality between the tropics and the arctic zones is scarcely described and results are inconsistent. The aim of this study was to describe domestic feline seasonal patterns under a natural temperate photoperiod. A total of 372 estrous cycles were studied in 34 post pubertal cats during 900 days. The queens were housed in a cat colony (31°25' South Latitude, 64°11' West Longitude), acclimated under natural photoperiod and daily observed for reproductive behavior. Vaginal cytology was conducted three times a week. For each cat the number of estrous cycles and days in estrus per month for each year were recorded. The months of the year were grouped in four periods of 3 months each according to day length and photoperiod. Comparisons of estrous days among periods were performed by ANOVA for repeated measures. All the cats had estrous cycles throughout the year without intervals of anestrus. Mean number of estrous days differed among the periods (P<0.01), those of long day length and ascending photoperiod being greater (12.5±0.6) to those of descending photoperiod either with long (8.9±0.7) or short (9.3±0.7) days. When the two periods with ascending day lengths were merged and compared to the two periods with descending day lengths merged, the number of estrous days were greater when day length ascended (P<0.01). Nearly 60% of the estrous cycles occurred during the periods of ascending day length. It is concluded, that domestic cats under natural temperate photoperiod have estrous cycles throughout the year showing peak activity the months with increasing photoperiod.

The GnRH antagonist acyline prevented ovulation, but did not affect ovarian follicular development or gestational corpora lutea in the domestic cat

Two experiments were conducted to investigate the effects of the GnRH antagonist acyline (330 microg/kg, given sc) on ovarian follicular development and ovulation, as well as on pregnancy maintenance in domestic cats. In the first experiment, seven queens in proestrus (total of 24 proestrus periods), were randomly assigned to treatment with either acyline (ACY; n=17) or a placebo (PLC; n=7). All queens were mated with a fertile tomcat. In the ACY and PLC groups, cessation of estrus occurred (mean+/-SEM) 7.0+/-1.3 and 7.0+/-1.7 d after treatment (P>0.1), ovulation occurred in 2 of 17 and all seven estrus periods (P<0.05), and pregnancy rates were 1 of 16 and 7 of 7 (P<0.05), respectively. In the ACY and PLC groups, intervals from treatment to the onset of the ensuing proestrus were 18.4+/-1.7 and 120+/-17.2 d. In the second experiment, 14 pregnant queens were randomly allocated, according to their mating date, to treatment with acyline in early pregnancy (from 20 to 25 d, n=3), mid pregnancy (from 26 to 45 d; n=4), late pregnancy (> 45 d; n=3), or injection of a placebo in early (n=1), mid (n=2), or late pregnancy (n=1). Ultrasonographic assessments of the uterus were done every second day for 2 wk post treatment, and serum progesterone (P(4)) concentrations were determined before treatment, and at 7 and 14 d after treatment. No pregnancies were prematurely terminated and post-treatment P(4) concentrations did not differ among treatment groups (P>0.1). In conclusion, in the domestic cat, GnRH withdrawal by acyline prevented ovulation when given in early follicular phase (proestrus), but did not significantly affect luteal function during pregnancy.

Comparison of oral pulse methotrexate with placebo in the treatment of severe glucocorticosteroid-dependent asthma

BACKGROUND

This study compared the efficacy of weekly oral administration of methotrexate and placebo in treatment of 24 subjects with chronic glucocorticosteroid-dependent asthma.

METHODS

The 33-week randomized, double-blind, placebo-controlled crossover trial compared once weekly 15 mg doses of methotrexate with placebo. At the time of entry, the subjects' mean dosage of prednisone was 23.8 mg/day (range, 12.5 to 85 mg) and glucocorticosteroid therapy had been used continuously for a mean duration of 78 months (range, 5 to 360 months).

RESULTS

Of the 21 subjects who completed the study, 13 tolerated lower daily prednisone doses during methotrexate treatment compared with placebo. When treated with methotrexate, subjects required 14.2% less prednisone than when treated with placebo (p = 0.0447), their subjective symptom scores improved 21.4% (p < 0.05), and mean forced expiratory volume in 1 second values tended to improve. Mean serum theophylline levels did not change significantly between the methotrexate and placebo arms of the study. Adverse effects were minimal, with nausea and headache occurring twice as often during methotrexate therapy compared with placebo.

CONCLUSION

Short-term, low-dose, pulse therapy with orally administered methotrexate results in a decrease in the daily glucocorticosteroid requirement in a majority of subjects with severe asthma and is accompanied by improvement in subjective symptom scores without unacceptable side effects or deterioration of pulmonary function.

Multiple stings by imported fire ants (Solenopsis invicta), without systemic effects

This is the first case report of imported fire ants invading a building and aggressively attacking a human being, resulting in multiple stings. This case illustrates that, although the venom has a high LD50 in mice, it does not induce toxic systemic effects in humans when the venom is introduced intradermally.

Rheumatic manifestations of human immunodeficiency virus infection

PURPOSE

The prevalence and characteristics of the rheumatic and extra-rheumatic manifestations of human immunodeficiency virus (HIV) infection were determined in a prospective manner.

PATIENTS AND METHODS

One hundred one patients with HIV infection were consecutively interviewed and examined. The prevalence of autoantibodies and their association with rheumatologic symptoms were also determined.

RESULTS

The musculoskeletal system was involved in 72 patients. Thirty-five patients had arthralgias, 10 had Reiter's syndrome, two had psoriatic arthritis, two had myositis, and one had vasculitis. Also found were two previously unreported syndromes. The first, occurring in 10 patients, consisted of severe intermittent pain involving less than four joints, without evidence of synovitis, of short duration (two to 24 hours), and requiring therapy (ranging from nonsteroidal antiinflammatory drugs to narcotics). The second, occurring in 12 patients, consisted of arthritis (oligoarticular in six patients, monoarticular in three patients, and polyarticular in three patients) involving the lower extremities and lasting from one week to six months. The synovial fluid of five patients (three with arthritis, one with Reiter's syndrome, and one with psoriatic arthritis) was sterile and inflammatory.

CONCLUSION

Musculoskeletal complications are common in advanced stages of HIV infection. Persons in a high-risk group for HIV infection who manifest oligoarthritis with or without any other extra-articular manifestation suggestive of Reiter's syndrome or other form of spondyloarthropathy should be tested for HIV.