Residual effect of lambdacyhalothrin on Triatoma infestans.

Insecticidal residual effect and triatomine infestation rates in houses of a community fumigated with lambdcyhalothrin (Icon) are reported. No mortality was observed in 5th-instar Triatoma infestans nymphs in 72-hr exposure test on three different surfaces, one month after fumigation for a dose of 31.5 mg am/m2. However, during post-exposure observation a mortality of 60% was recorded for those insect exposed on sprayed woodboard. The results observed with mud-containing treated walls, were markedly poorer (0% of mortality). Twelve month after spraying 40% of mortality was observed on first-instar T. infestans nymphs in 72-hr exposure test on woodboard, but lower mortality rates were observed in mud-containing materials. When the effect of deltamethrin (109 mg ai/m2) and lambdcyhalothrin (94 mg ai/m2) was compared, the former did not appear to be superior at similar loads. Both have showed a mortality rate of 30% on 5th-instar T. infestans nymphs three months post-fumigation. The dose utilized in the field fumigation was enough to get a significant (p < 0.0001) control of triatomine domestic infestation, since it was sufficient to keep 95% of the houses uninfested throughout 21 months following treatment, when compared with baseline situation. A remarkable knock-down effect on adult and nymphs forms of the insect and a high in situ mortality were observed as a result of its application, even at very low doses.

Acute Chagas' disease in non-human primates. 1. Chronology of clinical events, clinical chemistry, ECG, radiology, parasitemia, and immunological parameters in the Cebus apella monkey.

Forty Cebus apella monkeys free from Chagas' disease were subcutaneously infected with 3 x 10(5) trypomastigotes of the Ypsilon strain of T. cruzi and followed-up for 6 months. Seventeen monkeys were controls. Body weight, temperature, direct parasitemia (DP), IgM and IgG were determined weekly. Hematology was performed weekly up to day 40 p.i. and monthly thereafter. Clinical chemistry was performed every two weeks up to day 33 p.i. and monthly thereafter. ECG was performed weekly up to day 47 p.i. and at 2,3, and 6 months p.i. Chest X-ray was done at 45 days, 4 and 6 months p.i. Xenodiagnosis was only performed after two negative DP. All infected monkeys developed fever, beginning 6.0 +/- 0.6 day p.i. and lasting 21.9 +/- 6.7 days, and lost 14% of their body weight the first month, 11% the third month and 7% the 6th month. DP was already detected 4.4 +/- 0.29 days after infection and it was detectable in all monkeys up to 96.0 +/- 6.9 days p.i. Cyclical peaks of parasitemia were observed throughout the study. IgM and IgG titers which permitted a diagnosis of T. cruzi infection occurred at 33.0 +/- 2.9 days p.i., respectively. Fifty-seven percent of infected monkeys presented ECG alterations one week after inoculation reaching a maximum of 86% at the third week. A normocytic, normochromic anemia was observed in all monkeys being significantly (p less than 0.02) more severe in the infected animals. No effects of T. cruzi on the clinical chemistry were observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Body measurements, hematology, and serum chemistry values of the adult Cebus apella monkey.

Body measurements, hematology, and serum chemistry values were studied in 40 captured male and female Cebus apella monkeys. Some significant dimorphism with male predominance was found. Significant differences were also found for hemoglobin and red cell volume between males and females. Differential white blood cell counts indicated a marked predominance of lymphocytes and high values of gamma globulin in both sexes.

Rat brain norepinephrine release during progesterone-induced LH secretion.

The administration of 1.5 mg of progesterone to ovariectomized estrogen-primed rats induced a surge in plasma norepinephrine (NE) preceding the pituitary LH release. The injection of reserpine (2 mg/kg) 2 h prior to progesterone completely blocked the progesterone effects on both NE and LH plasma surges. On the other hand, the adminitration of phenoxybenzamine prior to progesterone, blocked the steroid effect on LH without inhibiting the plasma NE rise. Contrarily, the alpha-blocker was able to induce a rapid increase in the amine levels 2 h after its injection. The determination of NE in the anterior hypothalamus of these rats revealed that simultaneously with the plasma NE rise induced by progesterone there was a fall in the hypothalamic amine levels. Both reserpine and phenoxybenzamine caused a depletion in the amine content of the anterior hypothalamus. In experiments measuring the arteriovenous difference in the concentration of NE across the brain following progesterone-induced LH release, it was found that most NE comes from the brain. The amine rise was evident in the jugular vein while the arterial NE concentration showed a slight increase. These findings raise the possibility that the changes in circulating NE may reflect an enhanced noradrenergic activity occurring in the brain from which the LH surge results.

Plasma levels of norepinephrine during the periovulatory period in normal women. Further studies.

Eleven normally cycling women in whom laparotomy was indicated for benign gynecologic pathology were studied. Surgery was performed on day 0 (expected day of ovulation). Blood samples were drawn daily from day -8 to day -4, and every 8 hours from day -3 to day +2; estradiol (E2), progesterone (P), norepinephrine (NE), and LH were determined by RIA. Ovulation was certified by ovarian visualization and biopsy during laparotomy. In nine ovulatory patients mean E2 peak was found 48 hours before LH peak. Mean NE levels showed minimal variations until 48 hours before LH peak; 8 hours after E2 peak mean NE values increased significantly, fell 8 hours later, and rose immediately again, reaching maximal levels 24 hours after E2 peak. These values remained high until 16 hours before the LH peak and decreased gradually, thereafter reaching basal levels 32 hours after LH peak. Two anovulatory patients showed an atypical pattern of ovarian steroids and LH secretion and NE showed large variations without any correlation with estradiol or LH levels. This study confirms previous findings in women and experimental work in animals regarding the existence of a noradrenergic trigger mechanism to the LH ovulatory discharge.

Studies on biochemical characteristics of an early decidual protein.

Previous work in our laboratory has demonstrated the specific synthesis of a soluble protein (A) in the rat endometrium on day L4 of pseudopregnancy 1 h after the decidual induction; the A protein synthesis being higher in the antimesometrial region (AMR) than in the mesometrial one. We have now examined in the AMR of rat endometria on day L4 of pseudopregnancy: 1) the effect of cycloheximide (500 microgram, i.p. 30 min before decidual induction) on the biosynthesis of the A protein, and 2) the effect of actinomycin D (Act. D) (5 microgram/uterine horn 60 min before the decidual stimulation) on the induction of A protein synthesis. The synthesis of the A protein was determined by acrylamide gel electrophoresis of endometrial soluble proteins after double-labeling incorporation of amino acids. Results showed that: 1) the cycloheximide inhibited the synthesis of the A protein which indicates a de novo protein synthesis; 2) the Act. D inhibited the A synthesis suggesting that synthesis of an Act. D-sensitive product is one of the earliest macromolecular synthetic events after decidual induction.

Pituitary and ovarian response to acute stimulation with LH-RH in normal and anovulatory women.

The LH FSH estradiol and progesterone responses to acute stimulation with LH-RH were studied in 12 normal women with ovulatory cycles (4 in the initial follicular phase, 4 in the mid-follicular phase and 4 in the late follicular phase) and in two castrated women, two under hormonal contraception, two with ovarian amenorrhea, twelve with central amenorrhea of no detectable origin (6 with normal and 6 with low basal gonadotrophins), eleven anovulatory patients with pseudomenstruation, two with anorexia nervosa, and two with pituitary amenorrhea. Each woman received a rapid i.v. injection of 100 microgram synthetic LH-RH at 9:00 a.m. Serum levels of LH, FSH, estradiol and progesterone were determined by radioimmunoassay in samples collected before and 60, 120, 240 and 480 minutes after injection. The findings were : 1) A significant rise in estradiol and progesterone levels, in addition to LH and FSH elevation, in normal women; 2) A lack of ovarian steroid response in the castrated women and in ovarian amenorrheas, which suggests that the source of steroid response to stimulation is not extragonadal; 3) Significant differences in the responses of the four hormones to LH-RH in the women with central amenorrhea in comparison with the normal group with great variability of results; the steroid response in the presence of a positive LH response might correlate with the severity and/or prognosis of the disorder, a point deserving further study; 4) In anovulatory women with pseudomenstruation, LH responses for the most part normal, and particularly, progesterone responses.

PIP: Simultaneous pituitary and ovarian responses to acute stimulation (100 mcg iv injection) with luteinizing hormone-releasing hormone (LH-RH) in normal women at different times of the menstrual cycle were determined and the results were compared with those obtained in women with anuvulation from different causes. There were 12 normal women, 2 women who had had surgical oophorectomy, 2 who were taking combined hormonal contraceptives, 1 with amenorrhea following pelvic irradiation, 1 with gonadal dysgenesis, and 2 with anorexia nervosa. There were also 12 patients with secondary amenorrhea without detectable pathology. All patients received an iv injection of 100 mcg of synthetic LH-RH. In the normal patients basal LH levels were significantly (p .05) higher on Days 13-14 of the cycle than on Days 4-5. In all 3 phases of the cycle, LH reached peak poststimulation levels within 60 minutes after LH-RH injection. Castrate women showed basal LH levels and LH response profiles similar to normals. There were no estadiol or progesterone responses in this group. Women using hormonal contraception showed low basal levels of both gonadotropins with poststimulation LH response but no follicle stimulating hormone response. Estradiol response in this group was slightly lower and more sustained than in normal women. In patients with ovarian amenorrhea, responses were similar to those in castrated women. In patients with anorexia nervosa findings were normal.

The secretion of progesterone during the periovulatory period in women with certified ovulation.

A pre-LH peak rise of progesterone in peripheral blood has been found in 13 normal cycling women whose ovulation was confirmed by biopsy of the corpus luteum through serial determination of progesterone and LH performed every 8 h during the periovulatory period. The progesterone rise began as an average 22 h (16-40 h) prior to the LH peak. The maximal preovulatory rise took place 9.6 h (0-24 h) before the LH zenith, remaining low for approximately 17 h when an abrupt rise of progesterone took place. The progesterone peak was detected in the morning samples in 11 of 13 patients studied. The progesterone rise was always followed by an LH peak and the highest peak of progesterone was trailed by the highest LH peak in all the patients except one.

Changes in (3H)leucine incorporation into pineal proteins following estradiol or testosterone administration: involvement of the sympathetic superior cervical ganglion.

Pineal denervation by superior cervical ganglionectomy (Gx) decreased high affinity binding of estradiol (E2) to the pineal cytosol of female rats and of testosterone to the cytosol of male rats by 40 and 26% and by 75 and 80%, 5 and 14 days after sugery; hormone binding remained unchanged up to 24 h after surgery. Binding to the nuclear fraction decreased sigificantly by 2 weeks after incorporation of (3H) leucine into pineal proteins in Gx. A single injection of E2 (mug) to testosterone propionate (TP) (500 mug) failed to increase the Gx rats when injected 1 or 5 days after surgery. Significant increases were observed in sham-operated controls or in rats subjected to bilateral decentralization of ganglia; however on the 5th day an impairment was observed in hormone ability to enhance [3H]leucine incorporation in decentralized rats. The administration of isoproterenol 19 and 3 h before sacrifice replenished pineal-binding sites for E2 and testosterone in Gx rats, but failed to restore the responsiveness of denervated pineals to hormone administration. Moreover, E2 or TP treatment blocked the increase in labeled amino acid incorporation into proteins brought about by isoproterenol per se. The administration of propranolol 2 and 7 h after hormone injection decreased the ability of E2 and TP to enhance [3H]leucine incorporation by 55 and 41%, respectively. Tyrosine hydroxylase activity of the superior cervical ganglia decreased by 36 and 41% 6 h after E2 or TP administration, and by 43 and 47% after 3 daily injections of the hormones, whereas pineal tyrosine hydroxylase remained unchanged. Hormone treatment for 3 days increased the in vitro uptake of norepinephrine by the ganglia but did not affect uptake in the pineal gland. These data indicate that the integrity of neurons of the superior cervical ganglia is an absolute requirement for E2 and testosterone to enhance [3H]leucine incorporation into pineal proteins in rats.

Plasma levels of norepinephrine (NE) during the periovulatory period and after LH-RH stimulation in women.

In three normally cycling women studied daily from day 10 to 17 of the menstrual cycle, the levels of circulating norepinephrine showed a sharp rise preceding or concomitantly with the ovulatory LH surge. In two patients the norepinephrine peak took place 24 hr. previously to the LH rise and in the third one it occurred simultaneously. The simultaneous determination of ovarian hormones and norepinephrine showed no temporal correlation between this catecholamine and either estradiol or progesterone. On the other hand, after a single intravenous 100 mug dose of LH-RH, a significant rise in plasma norepinephrine, preceding the LH peak, was found in the four patients studied. The determination of norepinephrine at 3 minute intervals beginning one minute after LH-RH injection showed a significant rise in the amine levels ranging from 5 to 10 times in respect to basal values between 1 and 6 minutes after LH-RH stimulation. In these patients a second peak of norepinephrine occurred simultaneously with the maximal response of LH, which rose to peak levels after 18 minutes in one patient and after 24 minutes in the other. These findings are discussed with respect to the origin and role of increased amounts of plasma norepinephrine related to the LH surge.

Correlation between catecholamine content of the human Fallopian tube and the uterus and plasma levels of estradiol and progesterone.

The content of catecholamines in the Fallopian tube and the uterus and the plasma levels of estradiol and progesterone were studied in cycling women. During the follicular phase norepinephrine levels were 33.4+/-7.1, 50.5+/-8.0, and 145.7+/-43.6 ng. per gram of wet tissue in the external, middle, and internal segments of the Fallopian tube, respectively. During the luteal phase norepinephrine content increased significantly in the external and middle portions (219.3+/-57.0 and 206.2+/-34.3 ng. per gram) whereas it remained unchanged in the internal one (185.2+/-53.6 ng. per gram). The NE content of the external and middle segments correlated significantly with plasma progesterone levels (r = 0.76 and 0.82, respectively, whereas oviductal epincphrine levels did not show significant changes as a function of the stage of the menstrual cycle. Uterine epinephrine content decreased by 67 per cent during the luteal phase whereas norepinephrine remained unchanged.