The influence of drug interval on the effect of methotrexate and fluorouracil in the treatment of advanced colorectal cancer.

The importance of the interval between methotrexate (MTX) and fluorouracil (5-FU) was studied in 168 patients with previously untreated, measurable, advanced colorectal cancer. They were randomized to receive MTX 200 mg/m2, followed by 5-FU 600 mg/m2 either 24 hours (arm A) or 1 hour (arm B) after MTX. All patients received leucovorin (LV) 24 hours after MTX, 10 mg/m2 orally every 6 hours for six doses. The regimen was repeated every 2 weeks, with 5-FU escalation as tolerated. Arm A was significantly better than arm B with respect to overall response rate (29% v 14.5%, P = .026), time to progression (TTP; median, 9.9 months v 5.9 months, P = .009), and survival (median, 15.3 months v 11.4 months, P = .003). Significant differences between arms were not found in response rate, median TTP, or median survival for the subgroup of patients with rectal primaries who comprised 20% of the patients in each arm. Significant factors prognostic for survival were performance status and number of metastases, as well as treatment. Age did not influence survival. Toxicity was similar in both arms and was primarily gastrointestinal. More mucositis was seen in arm A. There were four toxic deaths secondary to neutropenia and infection (one from arm A and three from arm B) and three other deaths (two from arm A and one from arm B) that were possibly drug-related. The combination of MTX with LV rescue and 5-FU is an active regimen in advanced colorectal cancer; its efficacy is increased in colon, but not rectal cancer, when the interval between MTX and 5-FU is long (24 hours) rather than short (1 hour).

Nurses' recognition of delirium and its symptoms: comparison of nurse and researcher ratings.

BACKGROUND: Nurses play a key role in recognition of delirium, yet delirium is often unrecognized by nurses. Our goals were to compare nurse ratings for delirium using the Confusion Assessment Method based on routine clinical observations with researcher ratings based on cognitive testing and to identify factors associated with underrecognition by nurses. METHODS: In a prospective study, 797 patients 70 years and older underwent 2721 paired delirium ratings by nurses and researchers. Patient-related factors associated with underrecognition of delirium by nurses were examined. RESULTS: Delirium occurred in 239 (9%) of 2721 observations or 131 (16%) of 797 patients. Nurses identified delirium in only 19% of observations and 31% of patients compared with researchers. Sensitivities of nurses' ratings for delirium and its key features were generally low (15%-31%); however, specificities were high (91%-99%). Nearly all disagreements between nurse and researcher ratings were because of underrecognition of delirium by the nurses. Four independent risk factors for underrecognition by nurses were identified: hypoactive delirium (adjusted odds ratio [OR], 7.4; 95% confidence interval [CI], 4.2-12.9), age 80 years and older (OR, 2.8; 95% CI, 1.7-4.7), vision impairment (OR, 2.2; 95% CI, 1.2-4.0), and dementia (OR, 2.1; 95% CI, 1.2-3.7). The risk for underrecognition by nurses increased with the number of risk factors present from 2% (0 risk factors) to 6% (1 risk factor), 15% (2 risk factors), and 44% (3 or 4 risk factors; P(trend)<.001). Patients with 3 or 4 risk factors had a 20-fold risk for underrecognition of delirium by nurses. CONCLUSIONS: Nurses often missed delirium when present, but rarely identified delirium when absent. Recognition of delirium can be enhanced with education of nurses in delirium features, cognitive assessment, and factors associated with poor recognition.

Stimulation of cyclic adenosine 3',5'-monophosphate production enhances hypothalamic luteinizing hormone-releasing hormone release without increasing prostaglandin E2 synthesis: studies in prepubertal female rats.

A role for cAMP in the process of LHRH release was suggested several years ago, but only recently has the validity of this notion come under close scrutiny. In the present experiments we have used three probes, which stimulate adenylate cyclase activity via different mechanisms, to determine whether an increase in endogenous cAMP results in LHRH release from the hypothalamus of prepubertal female rats. Median eminences from juvenile, 28-day-old animals were incubated in vitro with either forskolin (F), cholera toxin (CT), or pertussis toxin (PT). All three substances enhanced LHRH release. The estimated ED50 values were 28.7 microM and 20.0 ng/ml, for F and PT, respectively. The effect of CT appeared biphasic and thus no ED50 could be calculated. None of these agents increased the release of prostaglandin E2 (PGE2), an obligatory component in the process of norepinephrine-induced LHRH secretion. Doses of PGE2 and F, which were maximally effective in stimulating LHRH release when administered separately, did not produce any further response when administered concomitantly, thus suggesting that PGE2 and F act along a common pathway. Blockade of phosphodiesterase activity with 1-methyl-3-isobutylxanthine increased LHRH secretion without enhancing PGE2 release, implying that cAMP metabolism was elevated in the median eminence nerve terminals in vitro. Addition of 1-methyl-3-isobutylxanthine augmented the LHRH response to CT and PT, but it did not increase further the already marked LHRH response to PGE2 or F. The results indicate that both an increase in adenylate cyclase activity and a decrease in phosphodiesterase activity lead to LHRH release from the median eminence. They also suggest that, upon proper (neurotransmitter?) stimulation, cAMP production increases subsequent to the activation in PGE2 synthesis, which itself causes LHRH release. Furthermore, the capacity of PT to induce LHRH release suggests the involvement of an inhibitory guanine nucleotide-binding regulatory protein in transducing inhibitory inputs impinging on LHRH-secreting neurons.

The gene encoding nerve growth factor is expressed in the immature rat ovary: effect of denervation and hormonal treatment.

The rat ovary is innervated by sympathetic nerve fibers. Since the development and survival of peripheral sympathetic neurons innervating nonreproductive organs have been shown to depend on the production of nerve growth factor (NGF) by the innervated tissues, the present experiments were undertaken to determine if the immature rat ovary has the capability of synthesizing NGF. Blot hybridization of ovarian polyadenylated RNA (A+-RNA) to a NGF cRNA probe revealed the presence of a 1.3- to 1.4-kilobase (kb) mRNA species similar to mature NGF mRNA detected in mouse submaxillary gland, a source rich in NGF. Quantitation of NGF protein by a sensitive and specific two-site enzyme immunoassay demonstrated the presence of NGF in juvenile ovaries at levels comparable to those found in other sympathetically innervated tissues. Neither denervation of the ovary nor treatment with gonadotropins (hCG and FSH) or somatomammotropins (PRL and GH) affected the levels of NGF mRNA. However, denervation significantly increased NGF levels, suggesting that, as in other target tissues, denervation prevents the retrograde transport of NGF by the sympathetic terminals and leads to accumulation of the protein at its site of production. It is concluded that 1) the developing ovary is able to both transcribe the NGF gene and translate its mRNA into NGF protein; and 2) the NGF content in the ovary is regulated by its innervation. The results provide the biochemical basis for the concept, elaborated in the companion paper, that NGF through its trophic actions on ovarian sympathetic neurons contributes to the regulation of ovarian development and, hence, to the acquisition of female reproductive capacity.

Outcome of children in the indomethacin intraventricular hemorrhage prevention trial.

BACKGROUND: For preterm infants, intraventricular hemorrhage (IVH) may be associated with adverse neurodevelopmental outcome. We have demonstrated that early low-dose indomethacin treatment is associated with a decrease in both the incidence and severity of IVH in very low birth weight preterm infants. In addition, we hypothesized that the early administration of low-dose indomethacin would not be associated with an increase in the incidence of neurodevelopmental handicap at 4.5 years of age in our study children. METHODS: To test this hypothesis, we provided neurodevelopmental follow-up for the 384 very low birth weight survivors of the Multicenter Randomized Indomethacin IVH Prevention Trial. Three hundred thirty-seven children (88%) were evaluated at 54 months' corrected age, and underwent neurodevelopmental examinations, including the Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R), the Peabody Picture Vocabulary Test-Revised (PPVT-R), and standard neurologic examinations. RESULTS: Of the 337 study children, 170 had been randomized to early low-dose indomethacin therapy and 167 children had received placebo. Twelve (7%) of the 165 indomethacin children and 11 (7%) of the 158 placebo children who underwent neurologic examinations were found to have cerebral palsy. For the 233 English-monolingual children for whom cognitive outcome data follow, the mean gestational age was significantly younger for the children who received indomethacin than for those who received placebo. In addition, although there were no differences in the WPPSI-R or the PPVT-R scores between the 2 groups, analysis of the WPPSI-R full-scale IQ by function range demonstrated significantly less mental retardation among those children randomized to early low-dose indomethacin (for the indomethacin study children, 9% had an IQ <70, 12% had an IQ of 70-80, and 79% had an IQ >80, compared with the placebo group, for whom 17% had an IQ <70, 18% had an IQ of 70-80, and 65% had an IQ >80). Indomethacin children also experienced significantly less difficulty with vocabulary skills as assessed by the PPVT-R when compared with placebo children. CONCLUSIONS: These data suggest that, for preterm neonates, the early administration of low-dose indomethacin therapy is not associated with adverse neurodevelopmental function at 54 months' corrected age.

The etiology and outcome of cerebral ventriculomegaly at term in very low birth weight preterm infants.

BACKGROUND: Despite improvements in survival data, the incidence of neurodevelopmental handicaps in preterm infants remains high. To prevent these handicaps, one must understand the pathophysiology behind them. For preterm infants, cerebral ventriculomegaly (VM) may be associated with adverse neurodevelopmental outcome. We hypothesized that although the causes of VM are multiple, the incidence of handicap at 4.5 years of age in preterm infants with this ultrasonographic finding at term would be high. METHODS: To test this hypothesis, we provided neurodevelopmental follow-up for all 440 very low birth weight survivors of the Multicenter Randomized Indomethacin Intraventricular Hemorrhage (IVH) Prevention Trial. A total of 384 children (87%) were evaluated at 54 months' corrected age (CA), and 257 subjects were living in English-speaking, monolingual households and are included in the following data analysis. RESULTS: Moderate to severe low pressure VM at term was documented in 11 (4%) of the English-speaking, monolingual survivors. High grade IVH and bronchopulmonary dysplasia (BPD) were both risk factors for the development of VM. Of 11 (45%) children with VM, 5 suffered grades 3 to 4 IVH, compared with 2/246 (1%) children without VM who experienced grades 3 to 4 IVH. Similarly, 9/11 (82%) children with VM had BPD, compared with 120/246 (49%) children without VM who had BPD. Logistic regression analysis was performed using birth weight, gestational age, gender, Apgar score at 5 minutes, BPD, sepsis, moderate to severe VM, periventricular leukomalacia, grade of IVH, and maternal education to predict IQ <70. Although maternal education was an important and independent predictor of adverse cognitive outcome, in this series of very low birth weight prematurely born children, VM was the most important predictor of IQ <70 (OR: 19.0; 95% CI: 4.5, 80.6). Of children with VM, 6/11 (55%) had an IQ <70, compared with 31/246 (13%) of children without VM. Children with VM had significantly lower verbal and performance scores compared with children without VM. CONCLUSIONS: These data suggest that, for preterm neonates, VM at term is a consequence of the vulnerability of the developing brain. Furthermore, its presence is an important and independent predictor of adverse cognitive and motor development at 4.5 years' CA.

Neurodevelopmental outcome at 36 months' corrected age of preterm infants in the Multicenter Indomethacin Intraventricular Hemorrhage Prevention Trial.

OBJECTIVES: Low-dose indomethacin has been shown to prevent intraventricular hemorrhage (IVH) in very low birth weight neonates, and long-term neurodevelopmental follow-up data are needed to validate this intervention. We hypothesized that the early administration of low-dose indomethacin would not be associated with adverse cognitive outcome at 36 months' corrected age (CA). METHODS: We enrolled 431 neonates of 600 to 1250 g birth weight with no IVH at 6 to 12 hours in a randomized, prospective trial to determine whether low-dose indomethacin would prevent IVH. A priori, neurodevelopmental follow-up examinations, including the Stanford-Binet Intelligence Scale and Peabody Picture Vocabulary Test-Revised, and standard neurologic examinations were planned at 36 months' CA. RESULTS: Three hundred eighty-four of the 431 infants survived (192 [92%] of 209 infants receiving indomethacin versus 192 [86%] of 222 infants receiving saline), and 343 (89%) children were examined at 36 months' CA. Thirteen (8%) of the 166 infants who received indomethacin and 14 (8%) of 167 infants receiving the placebo were found to have cerebral palsy. There were no differences in the incidence of deafness or blindness between the two groups. For the 248 English-monolingual children for whom IQ data follow, the mean gestational age was significantly younger for the infants who received indomethacin than for those who received the placebo. None of the 115 infants who received indomethacin was found to have ventriculomegaly on cranial ultrasound at term, compared with 5 of 110 infants who received the placebo. The mean +/- SD Stanford-Binet IQ score for the 126 English-monolingual children who had received indomethacin was 89.6 +/- 18.92, compared with 85.0 +/- 20.79 for the 122 English-monolingual children who had received the placebo. Although maternal education was strongly correlated with Stanford-Binet IQ at 36 months' CA, there was no difference in educational levels between mothers of the infants receiving indomethacin and the placebo. CONCLUSIONS: Indomethacin administered at 6 to 12 hours as prophylaxis against IVH in very low birth weight infants does not result in adverse cognitive or motor outcomes at 36 months' CA.

Low-dose indomethacin and prevention of intraventricular hemorrhage: a multicenter randomized trial.

OBJECTIVES: Parenchymal involvement of intraventricular hemorrhage (IVH) is a major risk factor for neurodevelopmental handicap in very low birth weight neonates. Previous trials have suggested that indomethacin would lower the incidence and severity of IVH in very low birth weight neonates. METHODS: We enrolled 431 neonates of 600- to 1250-g birth weight with no evidence for IVH at 6 to 11 hours of age in a prospective, randomized, placebo-controlled trial to test the hypothesis that low-dose indomethacin (0.1 mg/kg intravenously at 6 to 12 postnatal hours and every 24 hours for two more doses) would lower the incidence and severity of IVH. Serial cranial ultrasound examinations and echocardiographs were performed. RESULTS: There were no differences in the birth weight, gestational age, sex, Apgar scores, and percent of neonates treated with surfactant between the indomethacin and placebo groups. Within the first 5 days, 25 (12%) indomethacin-treated and 40 (18%) placebo-treated neonates developed IVH (P = .03, trend test). Only one indomethacin-treated patient experienced grade 4 IVH compared with 10 placebo-treated neonates (P = .01). Sixteen indomethacin-treated neonates and 29 control neonates died (P = .08); there was a difference favoring indomethacin with respect to survival time (P = .06). Eighty-six percent of all neonates had a patent ductus arteriosus on the first postnatal day; indomethacin was associated with significant ductal closure by the fifth day of life (P < .001). There were no differences in adverse events attributed to indomethacin between the two treatment groups. CONCLUSIONS: Low-dose prophylactic indomethacin significantly lowers the incidence and severity of IVH, particularly the severe form (grade 4 IVH). In addition, indomethacin closes the patent ductus arteriosus and is not associated with significant adverse drug events in very low birth weight neonates.

The genes encoding nerve growth factor and its receptor are expressed in the developing female rat hypothalamus.

Nerve growth factor (NGF), its messenger RNA (mRNA) and its receptor protein and mRNA are found in several brain regions. Little attention has been given to the possibility that the hypothalamus, which controls the endocrine system, may produce NGF and/or express NGF receptors. This would indicate the existence in this brain area of neuronal populations which are either target for NGF-responsive cells or sensitive to NGF, respectively. Blot hybridization of polyadenylated (poly(A)+) RNA to a mouse NGF cRNA probe revealed the presence of NGF mRNA in both the suprachiasmatic region (henceforth, called preoptic area [POA]) and medial basal hypothalamus (MBH) of developing female rats. The mRNA was already detectable on fetal day 18 and reached maximal levels around postnatal day 3 (MBH) and 12 (POA), declining thereafter. This pattern was temporally different than that of areas known to produce NGF, i.e., the neocortex (Cc) and hippocampus (Hc). In agreement with previous reports, NGF mRNA levels in these areas were negligible before birth, became maximal between the second and third week of postnatal life and decreased moderately thereafter. The concentration of NGF protein, measured by a two-site enzyme immunoassay, was 3 times higher in the POA than in the MBH at an infantile age (day 12), increasing 2-fold in the POA of juvenile animals (day 28) but not in the MBH. This developmental pattern was similar to that seen in the Hc, though the NGF concentrations were significantly lower in the POA.(ABSTRACT TRUNCATED AT 250 WORDS)

Antecedents of cerebral palsy in a multicenter trial of indomethacin for intraventricular hemorrhage.

OBJECTIVES: To determine if cerebral palsy (CP) rates were lower in the active treatment group compared with the control group, as improved survival rates of very low-birth-weight infants are postulated to be the cause of the increased incidence of CP in preterm infants, to evaluate relationships between multiple prenatal, perinatal, and postnatal variables and CP to understand better its antecedents in very low-birth-weight infants in the era of surfactant replacement therapy, and to determine the usefulness of a cranial ultrasonographic (US) scan in predicting CP. DESIGN: Inception cohort follow-up study as part of a randomized controlled trial of low-dose indomethacin sodium for the prevention of intraventricular hemorrhage. SETTING: Neonatal intensive care units at 3 medical centers. PATIENTS: Infants with birth weights between 600 and 1250 g were eligible, and 505 infants were enrolled in the original study. Of these infants, 440 (87%) survived; neurologic examinations were completed on 381 infants (86%) at 36 months corrected age. MAIN OUTCOME MEASURES: Statistical analyses were performed to identify the antecedents of CP, including the results of frequent cranial US scans obtained throughout the newborn period. RESULTS: Cerebral palsy was found in 36 (9.5%) of 381 infants at 36 months corrected age (range, 33-39 months corrected age). Univariate analysis identified chorioamnionitis, treatment with surfactant, bronchopulmonary dysplasia, and abnormal cranial US findings as antecedents of CP. Periventricular leukomalacia and ventriculomegaly were associated with the highest detection rates for CP (37% and 30%, respectively) with acceptable false-positive rates. Multivariate analysis identified bronchopulmonary dysplasia and an abnormal cranial US scan showing grade 3 to 4 intraventricular hemorrhage, periventricular leukomalacia, or ventriculomegaly as independent predictors of CP. Odds ratios for the detection of CP using cranial US findings tabulated by hospital day were in the range of 7 to 26 beginning on day 2. CONCLUSION: The results suggest that cranial US findings are useful predictors of CP during a patient's stay in the hospital.

Prostaglandin E2 releases luteinizing hormone-releasing hormone from the female juvenile hypothalamus through a Ca2+-dependent, calmodulin-independent mechanism.

Prostaglandin E2 (PGE2) has been implicated as a mediator of norepinephrine-induced luteinizing hormone-releasing hormone (LHRH) release from the hypothalamus. The present experiments were undertaken to examine the hypothesis that mobilization of Ca2+ from intracellular stores and cyclic AMP (cAMP) formation are involved in this effect. Incubation of median eminence (ME) nerve terminals from juvenile rats in Ca2+-free Krebs-Ringer bicarbonate buffer reduced, but failed to prevent the stimulatory effect of PGE2 on LHRH release. None of 5 calmodulin antagonists or a blocker of calmodulin-dependent kinase affected the LHRH response to PGE2. In contrast, inhibition of intracellular Ca2+ mobilization with TMB-8 or dantrolene in Ca2+-free medium prevented the LHRH releasing effect of PGE2. Similarly to PGE2, the stimulatory effect of the Ca2+ ionophore A 23187 on LHRH release was not affected by inhibition of calmodulin activity. This, however, blocked the increase in PGE2 formation induced by the ionophore. PGE2 evoked a dose-related increase in cAMP accumulation in Ca2+-containing medium and this effect was inhibited both by blockers of intracellular Ca2+ mobilization and by calmodulin antagonists. Surprisingly, removal of extracellular Ca2+ increased basal cAMP levels in the incubation medium without affecting LHRH release; PGE2 induced a further increase in cAMP which was prevented by inhibition of intracellular Ca2+ translocation. Stimulation of adenylate cyclase activity with forskolin (F) resulted in similar increases in cAMP levels both in the presence and absence of extracellular Ca2+. However, F failed to evoke LHRH release in Ca2+-free medium. The results indicate that: (a) the stimulatory effect of PGE2 on LHRH release involves mobilization of intracellular Ca2+ but not the participation of calmodulin; (b) the formation of PGE2 itself is calmodulin-dependent; (c) PGE2 stimulates cAMP formation through a calmodulin-dependent mechanism that requires translocation of intracellular (membrane?) Ca2+; (d) the cAMP system of a population of nerve terminals different from that responsive to PGE2 is normally subjected to a Ca2+-dependent inhibitory control; and (e) although PGE2 is a potent stimulator of cAMP formation in the ME and endogenously produced cAMP can induce LHRH release, in the absence of extracellular Ca2+ PGE2 stimulates LHRH release in a cAMP-independent manner.

Early-onset intraventricular hemorrhage in preterm neonates: incidence of neurodevelopmental handicap.

The neurodevelopmental outcome of very low birth weight infants experiencing early-onset intraventricular hemorrhage (IVH) occurring within the first 6 postnatal hours was compared with that of their peers without early-onset IVH at 3 years corrected age. The 440 surviving preterm infants (birth weight 600 to 1,250 g) who had been enrolled in a multicenter, prospectively randomized, controlled trial evaluating the efficacy of postnatal indomethacin to prevent IVH were evaluated with the Stanford-Binet Intelligence Scale and neurological examinations at 3 years corrected age. All study infants had echoencephalography between 5 and 11 hours of life, and testing is reported for all children residing in English monolingual households at 3 years corrected age (i.e., from the obstetric due date). Fifty five of the 73 (75%) infants with IVH within the first 5 to 11 hours survived to 3 years of age, compared with 385 of the 432 (89%) children without early-onset hemorrhage who were alive at 3 years corrected age (P<.001). Eleven of the 29 (38%) English monolingual children with early-onset IVH had Stanford-Binet intelligence quotient scores of less than 70, compared with 47 of the 249 (19%) children without early IVH (P = .03). Similarly, 7 of 28 (25%) early IVH children were found to have cerebral palsy, compared with 20 of 241 (8%) children without early IVH (P = .01). These data suggest that infants who experience the early onset of IVH are at high risk for both cognitive and motor handicaps at 3 years corrected age.

Pemphigus foliaceus successfully treated with mycophenolate mofetil as a steroid-sparing agent.

Pemphigus foliaceus is an autoimmune blistering disease of unknown origin with antibodies produced against desmoglein 1, an adhesive protein found in the desmosomal cell junction in the suprabasal layers of the epidermis. The disease is primarily treated with corticosteroids and corticosteroid-sparing immunosuppressive agents. We report a case of pemphigus foliaceus successfully treated with mycophenolate mofetil. It remains to be seen whether this agent has a significant effect on the course of the disease and remission induction.

The optimal application of surgical adhesive tape strips.

BACKGROUND: Surgical adhesive tape strips are often used in the early postoperative period after sutures are removed or are used in place of superficial sutures. There have not been any previous studies demonstrating their optimal application. OBJECTIVE: To demonstrate the optimal application pattern for adhesive strips. METHODS: Twelve subjects had adhesive strips applied to their forearms in four different patterns and the adherence over time was measured. RESULTS: The parallel, nonoverlapping pattern with complete coating of the skin surface with mastisol had the highest degree of adherence. CONCLUSION: Failure to coat the entire skin surface with adjunctive adhesive, overlapping of tape strips, and use of tacking strips are all detrimental to strip adherence and should be avoided in clinical practice.

Activation of estradiol-positive feedback at puberty: estradiol sensitizes the LHRH-releasing system at two different biochemical steps.

Experiments were performed to examine whether estradiol (E2) can influence some of the intraneuronal mechanisms involved in luteinizing hormone-releasing hormone (LHRH) release during the onset of puberty in the female rat. The capacity of median eminence (ME) nerve terminals to secrete LHRH, as determined by both their basal release of LHRH and by their response to prostaglandin E2 (PGE2) in vitro, increased significantly during the juvenile-early peripubertal periods of development (postnatal days 22-34). Ovariectomy (OVX) on day 22 led to a striking reduction in LHRH response to PGE2 on day 34. E2 administered via s.c. Silastic capsules, at a dose that reproduces juvenile serum E2 levels, restored the response. Simulation of first proestrous serum E2 levels in late juvenile (28-day-old) female rats enhanced both the sensitivity and the responsiveness of LHRH-containing terminals to PGE2. Furthermore, E2 enhanced the sensitivity and the responsiveness of LHRH terminals to norepinephrine (NE). This effect appeared to be related to both the increased LHRH response to PGE2 and an enhanced sensitivity of the PGE2-synthesizing pathway to NE. This is because MEs from E2-treated rats showed a marked increase in PGE2 release in response to a NE concentration which was barely effective in untreated controls. It is suggested that one of the mechanisms by which E2 activates the first preovulatory discharge of LHRH release in the female rat is by facilitating the occurrence of two different but sequentially related biochemical events: the stimulation of PGE2 formation by NE and the enhancement of LHRH release by PGE2.(ABSTRACT TRUNCATED AT 250 WORDS)

Evidence for the existence of substance P in the prepubertal rat ovary. I. Biochemical and physiologic studies.

The presence of substance P (SP) in the immature rat ovary was determined by radioimmunoassay (RIA) of acidic extracts. The extracts produced an inhibition-displacement curve of 125I-SP binding parallel to that generated by authentic SP in the SP RIA. Initial chromatographic characterization of ovarian SP in Sephadex G-25 revealed the presence of a molecular form that coeluted with authentic SP and a more abundant component that eluted earlier, suggesting the presence of a heavier peptide, immunologically similar to SP. Nevertheless, further characterization of these two seemingly different components by reversed-phase high-performance liquid chromatography (HPLC) demonstrated that both of them had a retention time similar to that of authentic SP. The ovarian concentration of SP-like immunoreactivity (SP-LI) varied in relation to the onset of puberty, with values increasing significantly between the late juvenile phase and the day of first proestrus. Substance P seems to be devoid of steroidogenic capacity since SP itself and its stable analog [pGlu5,MePhe8,Sar9]-SP5-11 (SP-A) failed to stimulate steroid secretion from either granulosa cells in culture or ovarian fragments in short-term incubation. Substance P also failed to stimulate prostaglandin E2 release from whole ovaries and to modify the steroidal response of cultured granulosa cells to follicle-stimulating hormone and to the beta 2-adrenergic agonist Zinterol. Production of SP-LI from granulosa cells in culture could not be detected under either basal or gonadotropin-stimulated conditions. These observations and the distribution of the peptide within the ovary presented in the companion paper (Dees et al., this issue) strongly suggest that SP is not directly involved in regulating steroidogenesis. Instead, SP may be a component of the so-called sensory innervation of the ovary, and among other undisclosed functions it may contribute to the regulation of ovarian blood flow.

Effect of experimental alterations in serum levels of 5 alpha-androstane-3 beta,17 beta-diol on the timing of puberty in the female rat.

It has been suggested that in the rat, 5 alpha-androstane-3 alpha,17 beta-diol (3 alpha-diol) is physiologically involved in restraining the onset of female puberty. To test this hypothesis several experiments were performed. In normal rats, serum levels of 3 alpha-diol decline slightly during the initial phases of puberty and then sharply several hours before the afternoon preovulatory LH surge on the day of first proestrus. Inhibition of 5 alpha-reductase activity with a highly specific inhibitor, 17 beta-N,N-diethylcarbamoyl-4-methyl-4-aza-5 alpha-androstane-3-one (4-MA) strikingly depressed both ovarian content and serum levels of 3 alpha-diol, but failed to advance vaginal opening or first ovulation. Administration of different doses of 3 alpha-diol to juvenile rats via Silastic capsules produced a dose-related increase in serum 3 alpha-diol levels. Titers attained ranged from values similar to those of untreated juvenile rats to levels more than 10-fold higher. None of the concentrations, however, inhibited the LH surge and ovulation induced by pregnant mare serum gonadotropin (PMSG). When a similar treatment was administered to normally maturing rats, only the high dose of 3 alpha-diol delayed the age of vaginal opening and of first ovulation. Serum 3 alpha-diol levels attained with this dose were markedly higher than those of untreated juvenile rats (1,086 +/- 267 vs. 124 +/- 14 pg/ml, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Dense inflammation does not mask residual primary basal cell carcinoma during Mohs micrographic surgery.

BACKGROUND: Areas of dense inflammation are commonly removed during Mohs micrographic surgery for basal cell carcinoma because of the concern that they may mask areas of tumor. OBJECTIVE: Our purpose was to determine whether inflammation masks tumor during Mohs surgery for primary basal cell carcinoma. METHODS: Twenty-five consecutive cases of primary basal cell carcinoma with areas of dense inflammation encountered during Mohs surgery were sectioned and stained with hematoxylin and eosin and Ber-EP4. RESULTS: In no cases did the dense inflammation mask residual tumor. CONCLUSION: Dense inflammation does not mask primary basal cell carcinoma during Mohs surgery and should be carefully evaluated before additional surgery is performed.

Activation of two different but complementary biochemical pathways stimulates release of hypothalamic luteinizing hormone-releasing hormone.

Evidence exists that a norepinephrine/prostaglandin E2 (PGE2)/cAMP pathway is involved in the regulation of luteinizing hormone-releasing hormone (LHRH) secretion. The aim of the present experiments was to determine if release of LHRH from the immature rat hypothalamus could also be stimulated by activation of protein kinase C. Median eminences from 28-day-old female rats were incubated in vitro with either dioctanoylglycerol (a synthetic diacylglycerol that selectively activates protein kinase C in intact cells) or 4 beta-phorbol 12 beta-myristate 13 alpha-acetate (another protein kinase C activator). Both agents increased LHRH release, the response to dioctanoylglycerol being more pronounced than that to the phorbol ester. This direct activation of protein kinase C was not accompanied by changes in PGE2 formation. Activation of the PGE2/cAMP pathway by either norepinephrine, PGE2, or forskolin (a stimulator of adenylate cyclase) increased LHRH release. Dioctanoylglycerol or phorbol ester in conjunction with either norepinephrine, PGE2 or forskolin resulted in an additive effect on LHRH release suggesting coexistence of both pathways. Phospholipase C, which activates protein kinase C via formation of diacylglycerol, increased the release of both LHRH and PGE2. This suggests that an increase in endogenous phospholipase C activity caused by neurotransmitter inputs may lead to both activation of protein kinase C and PGE2 formation. Blockade of cyclooxygenase activity by indomethacin obliterated phospholipase C-induced PGE2 release. The same treatment reduced the LHRH response by only 50% indicating that protein kinase C activation can cause LHRH release in the absence of PGE2 synthesis. It is suggested that the median eminence of the rat possesses a protein kinase C-dependent pathway that is coupled positively to LHRH release and complements PGE2/cAMP-dependent mechanisms. Norepinephrine, however, does not appear to be the neurotransmitter responsible for activating the protein kinase C pathway. Simultaneous activation of both pathways may provide a mechanism by which a large increase in LHRH secretion occurs, such as in the afternoon of first proestrus.