Forehead reduction and orbital contouring in facial feminisation surgery for transgender females.

Forehead reduction and orbital contouring form a considerable component of the procedures available to feminise the face in transgender females. In this paper I shall discuss the history and development of techniques to reduce bossing of the forehead and contour the orbits, and describe their classification, assessment, surgical approach, and complications.

Are vaccine strain, type or administration protocol risk factors for canine parvovirus vaccine failure?

Canine parvovirus (CPV) is a highly contagious and worldwide cause of serious and often fatal disease in dogs, despite the widespread availability of vaccines. Which vaccine-related factors are associated with vaccination failure is largely unknown, and there are no reports from Australia. In this study - the first national population-level CPV study of its kind ever conducted - we analysed data on 594 cases of apparent CPV vaccination failure reported from an Australian national surveillance system to determine whether vaccine strain, type or administration protocol are risk factors for vaccination failures. The strain of CPV used in vaccine manufacture was not significantly associated with vaccination failure in clinical practice. The vaccine type (killed versus attenuated vaccine) for puppies diagnosed with CPV was associated with a lower mean age at time of vaccination (P=0.0495). The age at administration of the last CPV vaccination a puppy received prior to presenting with disease was a significant (P=0.0334) risk factor for vaccination failure, irrespective of whether the vaccine was marketed for a 10-week or 12-week or greater vaccination finish protocol. There was also a strong negative correlation between age at last vaccination prior to disease and vaccination failure (P<0.0001): the later a puppy received this last vaccination, the lower the risk of vaccination failure. This supports the hypothesis that the use of final vaccination in puppies at less than 16 weeks of age predisposes to vaccination failure and warrants a final age for vaccination recommendation to be at least 16 weeks for all canine parvovirus vaccines, especially in outbreak situations. The large number of cases identified in this study confirms that CPV vaccination failure is occurring in Australia. Veterinarians should consider CPV as a differential diagnosis in cases with appropriate clinical presentation, regardless of the reported vaccination status of the dog.

Facial feminization surgery: current state of the art.

Facial feminization surgery (FFS) is a group of surgical procedures; the objectives of which are to change the features of a male face to that of a female face. This surgery does not aim to rejuvenate the face. FFS is carried out almost exclusively on transsexual women (males who are transitioning into females) and who have gender dysphoria. Some non-transsexual women may undergo some feminizing surgical procedures if they feel that they have male facial characteristics. Most transsexual women will have lived in role for sometime and they often undergo FFS before any other form of gender reassignment surgery as it assists them in passing as a female and integrating into everyday society. Various specific facial surgical procedures are utilized to feminize the face, often involving sculpture and contouring of the facial skeleton. These include correction of the hairline by scalp advance, contouring the forehead, brow lift, rhinoplasty, cheek implants, resection of the buccal fat pads of Bichat, lip lift and lip augmentation with dermis graft, mandible angle reduction and taper, genioplasty and thyroid shave. This article discusses the current state of the art in facial feminization surgery.

The effect of proton pump inhibitors on the human microbiota.

Proton pump inhibitors (PPIs) are commonly used to treat acid-related diseases, most notably gastroesophageal reflux disease. PPIs are designed to shut down the gastric proton pump (H+/K+-ATPase) of parietal cells, thereby raising the pH of the stomach. While effective, a number of side effects have been associated with PPI use. Naturally occurring bacteria, some of which are acid-producing and contain ATPase enzymes, have also been found within the stomach, upper gastrointestinal tract, and oral cavity. Likewise, a number of fungi are known to inhabit the human body; some of these fungi contain H+-ATPase enzymes. Recent literature has suggested that PPIs may be inadvertently affecting these bacteria and fungi in two different ways: 1) PPIs may directly target the proton pumps of the bacteria and fungi, and/or 2) PPIs may indirectly affect the microenvironment of the flora via changes in pH. These unintended interactions are exasperated by the systemic distribution of PPIs throughout the body and may potentially lead to some of the side effects observed with PPI use. Herein we summarize what is currently known about the interactions between the PPIs and the natural human microbiota.

Spatial tuning curves along the chick basilar papilla in normal and sound-exposed ears.

Intense sound exposure destroys chick short hair cells and damages the tectorial membrane. Within a few days postexposure, signs of repair appear resulting in nearly complete structural recovery of the inner ear. Tectorial membrane repair, however, is incomplete, leaving a permanent defect on the sensory surface. The consequences of this defect on cochlear function, and particularly frequency analysis, are unclear. The present study organizes the sound-induced discharge activity of cochlear nerve units to describe the distribution of neural activity along the tonotopic axis of the basilar papilla. The distribution of this activity is compared in 12-day postexposed and age-matched control groups. Spontaneous activity, tuning curves, and rate-intensity functions were measured in each unit. Discharge activity at 60 frequency and intensity combinations was identified in the tuning curves of hundreds of units. Activity at each of these criterion frequency/intensity combinations was plotted against the unit's characteristic frequency to construct spatial tuning curves (STCs). The STCs depict tone-driven cochlear nerve activity along the length of the papilla. Tuning sharpness, low- and high- frequency slopes, and the maximum response were quantified for each STC. The sharpness of tuning increased with increasing criterion frequency. However, within a frequency, increasing sound intensity yielded more broadly tuned STCs. Also, the high-frequency slope was consistently steeper than the low-frequency slope. The STCs of exposed ears exhibited slightly less frequency selectivity than control ears across all frequencies and larger maximum responses for STCs with criterion frequencies spanning the tectorial membrane defect. When rate-intensity types were segregated, differences were observed in the STCs between saturating and sloping-up units. We propose that STC shape may be determined by global mechanical events, as well as localized tuning and nonlinear processes associated with individual hair cells. The results indicated that 12 days after intense sound exposure, global and local contributions to spatially distributed neural activity are restored.

Ocular palsy following Le Fort 1 osteotomy: a case report.

A 33-year-old female patient developed an ipsilateral sixth nerve palsy and partial third nerve palsy following a Le Fort 1 osteotomy. Complete resolution occurred at 10 weeks. The likely mechanism of injury secondary to pterygo-maxillary dysjunction is highlighted, with description of the relevant anatomy. Previous cases of ocular motility complications following Le Fort 1 osteotomy are discussed. We recommend that significant care be taken in osteotome placement in the pterygo-maxillary fissure, particularly in those prone to unpredicted fractures such as older patients, or where the anatomy is congenitally abnormal or altered by previous surgery.

Barriers to bicycle helmet use.

OBJECTIVE: To determine why people do or do not wear helmets while bicycling. METHODS: A survey was conducted from August through October 1999. Two survey areas were chosen for this study: local public schools and paved bicycle trails. For the school arm of the study, 3 public elementary, middle, and high schools were selected from 3 different regions of Rochester, Minnesota, for participation in the study. For the bicycle arm of the study, 3 paved trails located in southeastern Minnesota were selected. A total of 2970 surveys were distributed to the public school system, and 463 surveys were collected from bicyclists on the paved bicycle trails. The survey population was split into 3 age categories for analysis: child (7-10), adolescent (11-19), and adult (older than 19). RESULTS: Of the 2970 surveys distributed to Rochester public schools, 2039 (69%) were returned for analysis. Seventy-eight of the surveys that were completed in the public school system were discarded for the following reasons: age <10 years (35), insufficient completion (24), and selection of every reason for not wearing a bicycle helmet (19). A total of 463 surveys were completed on the 3 paved bicycle trails. One survey from the paved bicycle trail arm of the study was discarded because of insufficient completion. The total number of surveys used for statistical analysis was 2424. The distribution of male (52.7%) and female (47.3%) participants was similar. No significant difference in bicycle helmet use was found between genders. The age groups with the highest rate of bicycle helmet use were 50 to 59 years (62%) and older than 59 years (70%). The age groups with the lowest rate of bicycle helmet use were 11 to 19 years (31%) and 30 to 39 years (30%). The most common reasons given for not wearing a bicycle helmet were "uncomfortable," "annoying," "it's hot," "don't need it," and "don't own one." Bicycle helmet use was significantly influenced by peer helmet use in all 3 age groups. Children also were more likely to wear a bicycle helmet when their parents wore bicycle helmets. A majority of respondents in all 3 age groups indicated that bicycle helmets provided either "moderate" or "great" protection from head injury, although significantly more adults (65.9%) than adolescents (43.9%) believed that the protection afforded by bicycle helmets was "great." Despite this belief, a majority of adolescents and adults indicated that there was only a "slight risk" of head injury when bicycling without a helmet. Participants in all 3 categories were more likely to wear a bicycle helmet when they indicated either that there was a "great risk" of head injury when bicycling without a helmet or that helmets provided "great protection" from head injury. Adolescents and adults who believed that bicycling without a helmet put one at "great risk" for head injury also were more likely to indicate that helmets provided "great protection" from head injury. CONCLUSIONS: The prevalence of bicycle helmet use remains low despite research indicating the high level of head injury risk when bicycling without a helmet and the significant protection afforded by bicycle helmets. With the information provided by this survey, a well-designed intervention to increase the use of bicycle helmets can be implemented. Suggestions for a campaign to promote an increase in bicycle helmet use include focusing efforts on males and females between 11 and 19 years and 30 and 39 years of age; educating the public on new bicycle helmet designs that address comfort, ventilation, and fashion; educating adolescents on the significant protection from head injury afforded by bicycle helmets; and educating the public on the risk and severity of head injury associated with bicycling without a helmet. The influence of parents and peers on bicycle helmet use may be targeted through education and statements such as, "If you wear a bicycle helmet, you are not only protecting yourself, you are also helping to protect your friends and/or children." bicycle, helmet, injury, accident, prevention.

An assessment of the aggressive potential of radiolucencies related to the mandibular molar teeth.

AIM: The purpose of this study was to outline the radiographic appearance of radiolucent lesions related to the molar teeth and to determine which features indicate aggressive lesions. PATIENTS AND METHODS: Panoramic radiographs were reviewed in 66 patients with radiolucencies related to the molar teeth. The radiographic appearances of the lesions were assessed with regard to location and size, and the relationship to the molar teeth. Radiographic evidence of aggression was assessed and pathology reviewed. RESULTS: Nineteen patients had aggressive and 47 had non-aggressive radiolucent lesions. The aggressive lesions included keratocysts, unicystic ameloblastoma, adenoid cystic carcinoma, giant cell granuloma, myxofibroma, chondroblastic osteosarcoma, mestastases and squamous cell carcinoma of the tongue invading the mandible. CONCLUSION: The differential diagnosis of radiolucent lesions in the mandible can be difficult using panoramic radiographs alone. Helpful features in determining aggression were older patients, larger lesions, Lodwick type IC tumour border, condition of the mandibular cortex, movement of adjacent teeth and the relationship of the inferior alveolar canal.

Paradoxical vocal fold motion: presentation and treatment options.

Paradoxical vocal fold motion is a rare disorder in which adduction of the folds occurs on inspiration. The disorder presents with signs of airway obstruction and often airway distress, so proper diagnosis by the otorhinolaryngologist is critical to subsequent management. We present a retrospective review of 10 patients with the diagnosis of paradoxical vocal fold motion seen over a 6-year period. Eight patients were females, and 6 required an acute airway intervention at presentation; 3 patients eventually underwent tracheotomy for respiratory decompensation. Six patients had a prior diagnosis of asthma, and this was determined to contribute to their respiratory status. Five patients were treated with botulinum toxin and 2 with flexible nasolaryngoscopic biofeedback, which improved the outcome. A review of the literature confirms a female predominance of patients presenting with paradoxical adduction and airway distress, often with a history of asthma and psychopathology. Our experience with botulinum toxin and biofeedback suggests that these procedures are viable treatment options in the management of patients with this disorder.

Ovarian interleukin-1 receptor antagonist in rats: gene expression, cellular localization, cyclic variation, and hormonal regulation of a potential determinant of interleukin-1 action.

It is hypothesized that the intraovarian interleukin (IL)-1 system plays a prominent role in the regulation of follicular development and ovulation. A central component of the intraovarian IL-1 system is the IL-1 receptor antagonist (IL-1RA), a protein acting as a pure IL-1 receptor antagonist and one for which intracellular (icIL-1RA) and secretory (sIL-1RA) varieties have been described. It was the objective of this study to explore rat ovarian IL-1RA gene expression, to establish the identity and relative abundance of its alternative transcripts, to study its cellular localization, to determine its cyclic variation, and to assess its hormonal regulation. Protected IL-1RA cDNA fragments corresponding to either sIL-1RA or icIL-1RA were barely detectable in untreated whole ovarian tissue of immature rat origin. However, sIL-1RA transcripts reached a maximal value (3.3-fold increase over untreated control values; p < 0.05) 12 h after hCG administration (time of projected ovulation). In situ hybridization localized IL-1RA to mural, antral, and cumulus granulosa cells. Modestly intense staining was also apparent in oocytes. The basal pattern of sIL-1RA expression by cultured whole ovarian dispersates was characterized by a spontaneous increase to a peak value at 4 h. The early (4 h) sIL-1RA burst proved IL-1-, nitric oxide-, and protein biosynthesis-independent. However, treatment with IL-1beta led to a secondary sIL-1RA peak at 48 h, an effect that was substantially reversed by IL-1RA. This stimulatory effect of IL-1beta on IL-1RA expression proved relatively specific, and nitric oxide independent, but contingent upon de novo protein biosynthesis. The in vitro expression of icIL-1RA was barely detectable. Taken together, these in vivo and in vitro observations 1) document the rat ovary as a site of IL-1RA (sIL-1RA > cIL-1RA) expression, 2) localize the relevant transcripts to the granulosa cell, 3) disclose peak expression at the time of ovulation, and 4) establish IL-1 dependence.

The rat intraovarian interleukin (IL)-1 system: cellular localization, cyclic variation and hormonal regulation of IL-1beta and of the type I and type II IL-1 receptors.

An increasing body of evidence supports the possibility that intraovarian interleukin (IL)-1 plays an intermediary role in the periovulatory cascade. To gain further insight into the intraovarian IL-1 hypothesis, we studied the cellular localization cyclic variation and hormonal regulation of IL-1beta, as well as of the type I and type II IL-1 receptors (IL-1R) in immature rats. In situ hybridization localized IL-1beta and type I IL-1R transcripts to the granulosa cell compartment, the innermost layers of the theca interna and to the oocyte of the untreated immature ovary. Molecular probing of whole ovarian material in the course of a simulated estrous cycle revealed a progressive preovulatory increase in IL-1beta and type I IL-1R transcripts to an in vivo peak at the time of ovulation (3.0- and 2.5-fold increases over untreated controls; P < 0.05). Comparable efforts to localize and probe for type II IL-IR transcripts failed to elicit a detectable signal. The basal in vitro expression pattern of IL-1beta and type II IL-1R transcripts by whole ovarian dispersates revealed an early (4 h) spontaneous increase to a peak (2.1- and 5.8-fold increases over time 0: P < 0.05) followed by a gradual decline to a 48 h nadir. Treatment of whole ovarian dispersates with the IL-1 receptor antagonist (IL-1RA) or with IL-1beta failed to alter the initial (4 h) burst of IL-1beta or of type II IL-1R expression thereby suggesting IL-1-independence. Treatment with hCG proved equally ineffective. However, longer-term treatment of whole ovarian dispersates with IL-1beta produced a significant secondary increase (5.9-fold over time 0; P < 0.05) in IL-1beta (but not type II IL-1R) transcripts by 48 h. This IL-1 effect was completely blocked by co-treatment with IL-1RA thereby suggesting mediation via a specific IL-1 receptor. Qualitatively comparable but quantitatively reduced results obtained for isolated granulosa cells. The basal in vitro expression pattern of type I IL-1R transcripts by whole ovarian dispersates revealed a progressive spontaneous increase (3.1-fold increase overall) over the 48 h culture. Treatment with IL-1beta produced a significant (P < 0.05) increase (5-fold) in type I IL-1R transcripts by 48 h, an effect which was completely blocked by co-treatment with IL-1RA. Taken together, these observations: (1) localize IL-1beta and its type I receptor to granulosa cells, the innermost layers of the theca interna and to the oocyte; (2) confirm their periovulatory in vivo expression pattern; (3) document their expression by untreated cultured whole ovarian dispersates; and (4) demonstrate their in vitro responsiveness to receptor-mediated/IL-1-driven autocrine amplification. The type II IL-1R was undetectable in vivo, its in vitro expression pattern proving IL-1- and hCG-independent. The periovulatory expression pattern of IL-1beta and its receptor (type I) is compatible with the notion that the intraovarian IL-1 system may play an intermediary role in the ovulatory process.

Congenital airway abnormalities in patients requiring hospitalization.

OBJECTIVE: To determine the cause of congenital airway abnormalities in pediatric patients requiring hospitalization for their respiratory status. DESIGN AND SETTING: Case series in a tertiary care center. PATIENTS: A 5-year retrospective chart review was conducted at our institution. A total of 174 patients were identified who required hospitalization for their respiratory status as a result of a congenital airway abnormality. RESULTS: Of the 174 patients, 114 (65.5%) were male and 60 (34.5%) were female. Eighty patients (47%) presented within the first 3 months of life. Forty-six patients (26%) were born prematurely, and 49 patients (28%) were diagnosed as having gastroesophageal reflux. The majority of patients (139 [80%]) had multiple presenting symptoms or signs. Stridor was the most common (129 [74%]), followed by accessory respiratory effort, cyanosis, apnea, and failure to thrive. Diagnosis was made at the time of surgical evaluation in 91% of the patients, with the remaining diagnoses made using radiological findings and/or clinical evaluation. Sixty-five patients (37%) had multiple sites of airway abnormalities; laryngeal abnormalities were noted almost 3 times as often as tracheal abnormalities (161 vs 62, respectively). Of the laryngeal abnormalities, laryngomalacia was the most common, followed by glottic web, subglottic stenosis, vocal-cord paralysis, and subglottic hemangioma. Tracheomalacia was the most common tracheal abnormality, followed by external compression and tracheal stenosis. Thirty-three patients (19%) required tracheotomy for management of recurrent respiratory decompensation. CONCLUSIONS: While congenital airway abnormalities are usually self-limited, those patients requiring hospitalization represent a group with a more severe respiratory status who have a greater chance of requiring tracheotomy. The recognizable percentage of patients with gastroesophageal reflux and prematurity accounts for comorbid factors in the need for hospitalization for respiratory issues related to congenital airway abnormalities.

Angioedema presenting in the retropharyngeal space in an adult.

PURPOSE: Hereditary angioedema is a rare disorder of deficient or dysfunctional C1-esterase inhibitor and usually manifests as edema of the face, tongue, supraglottis, extremities, or gastrointestinal tract. We report the case of a 40-year-old man with known hereditary angioedema who presented with a sore throat and a sensation of evolving airway obstruction. After a thorough search of the medical literature, we believe this to be the first reported case of angioedema manifesting in the retropharyngeal space. The pathophysiological factors of angioedema are discussed, along with its variable presentation and management issues. METHOD: Laryngoscopic examination was suggestive of posterior pharyngeal fullness; therefore, a computed tomographic scan of the neck was obtained, which showed a non-contrast-enhancing retropharyngeal edema from the base of the skull to below the level of the glottis. The patient had a history of multiple episodes of angioedema requiring hospitalization and three prior tracheotomies. RESULTS: Familiarity with the patient's history directed his rapid treatment course (including intravenous stanozolol, Solu-Medrol, and diphenhydramine), which significantly reduced his edema and avoided the need for tracheotomy. CONCLUSION: Hereditary angioedema may present in atypical locations, and expeditious treatment in a patient with a known history may avert the sequelae of evolving airway obstruction.

Cellular signal adaptation with damage control at low doses versus the predominance of DNA damage at high doses.

Ionizing radiation is known to potentially interfere with cellular functions at all levels of cell organization and induces DNA lesions apparently with an incidence linearly related to D, also at low doses. On the other hand, low doses have also been observed to initiate a slowly appearing temporary protection against causation and accumulation of DNA lesions, involving the radical detoxification system, DNA repair and removal of DNA damage. This protection apparently does not operate at high doses; it has been described to be nonlinear, increasing initially with D, beginning to decrease when D exceeds approximately 0.1-0.2 Gy, and eventually disappearing at higher D. The various adaptive responses have been shown to last individually from hours to weeks in different cell types and resemble responses to oxidative stress. Damage to DNA is continuously and endogenously produced mainly by reactive oxygen species (ROS) generated in a normal oxidative metabolism. This endogenous DNA damage quantitatively exceeds DNA damage from low-dose irradiation, by several orders of magnitude. Thus, the protective responses following acute low-dose irradiation may be presumed to mainly counteract the endogenous DNA damage. Accordingly, the model described here uses two dose-effect functions, a linear one for causing and a nonlinear one for protecting against DNA damage from whatever cause in the irradiated cells and tissues. The resulting net dose-risk function strongly suggests that the incidence of cancer versus dose in the irradiated tissues is much less likely to be linear than to exhibit a threshold. The observed cancer incidence may even fall below the spontaneous incidence, when D to cells is below approximately 0.2 Gy. However incomplete, these data support a reexamination of the LNT hypothesis.

Comparison of endoscopy and radiographic fluoroscopy in the evaluation of pediatric congenital airway abnormalities.

In order to assess the accuracy of conventional dynamic radiographic studies compared to endoscopy in the diagnosis of congenital airway abnormalities, we performed a retrospective chart review for the period between July 1991 to June 1996. A total of 186 patients were identified who required hospitalization for their respiratory status as a result of a congenital airway abnormality. Of these, 19% had both endoscopy and conventional dynamic radiographic evaluation (airway fluoroscopy, barium esophagography, or both). Eleven percent had fluoroscopy only, 62% had endoscopy only, and 9% had neither. In those patients who underwent both endoscopic and conventional dynamic radiographic evaluation, endoscopy was considered to be the definitive procedure for diagnosis. Laryngomalacia was present in 94% of these patients. Thirteen patients had multiple sites of airway abnormalities on endoscopy, and a total of 51 abnormalities were identified. Dynamic radiographic evaluation was correct in four, was suggestive of the abnormality in 12, did not recognize an abnormality in 33, and suggested a different diagnosis (not corresponding to endoscopy) in two. Thus, airway fluoroscopy and/or barium esophagography were correct or suggestive in 16 of 51 abnormalities (31%). We conclude that endoscopy is required in the majority of hospitalized patients for the precise diagnosis of a congenital airway abnormality. Conventional dynamic radiographic studies are helpful to confirm a suspected diagnosis in patients with a strong clinical history and physical examination. When the diagnosis is not clear based on the patient presentation, endoscopy is more definitive than conventional dynamic radiography in identifying pediatric congenital airway abnormalities.

Rat ovarian prostaglandin endoperoxide synthase-1 and -2: periovulatory expression of granulosa cell-based interleukin-1-dependent enzymes.

This laboratory has previously shown that interleukin-1 (IL-1), a putative intermediary in the ovulatory process, is capable of up-regulating PG biosynthesis by cultured whole ovarian dispersates from immature rats. In part, this phenomenon was attributable to the stimulation of ovarian phospholipase A2 activity. In this communication we examine the possibility that the PG-promoting property of IL-1 is also due to the up-regulation of PG endoperoxide synthase (PGS), the rate-limiting step in prostanoid biosynthesis. The in vivo expression of ovarian PGS-2 transcripts in the course of a simulated estrous cycle rose abruptly to a peak (35-fold increase over the control value; P < 0.05) 8-12 h after hCG administration (i.e. before or during projected ovulation). PGS-1 transcripts, in turn, were not significantly altered during the periovulatory period. Treatment of cultured whole ovarian dispersates with IL-1beta resulted in dose- and time-dependent up-regulation of PGS-2 transcripts (as well as of immunoreactive PGS-2 protein and PGE2 accumulation), characterized by an ED50 of 2 ng/ml and a maximal (72-fold) increase at 10 ng/ml. Although treatment with IL-1beta also led to an increase in PGS-1 transcripts and immunoreactive PGS-1 protein, the relative magnitude of the effect was markedly reduced compared with that of PGS-2. Cotreatment with an IL-1 receptor antagonist completely reversed the IL-1 effects, thereby suggesting mediation via the IL-1 receptor. The ability of IL-1 to up-regulate PGS-2 transcripts proved relatively specific, in that other cellular regulators (insulin-like growth factor I, activin A, endothelin-1, transforming growth factor-alpha, tumor necrosis factor-alpha, vascular endothelial growth factor, leukemia inhibitor factor, hepatocyte growth factor, or keratinocyte growth factor) were not effective. The optimal IL-1 effect required heterologous contact-dependent coculturing of granulosa and thecal-interstitial cells. Taken together, these observations 1) reaffirm (by molecular probing) the granulosa cell as the primary site of ovarian PGS-1 and PGS-2 expression, 2) document an increase in ovarian PGS-2 transcripts before ovulation, and 3) reveal a marked dependence of ovarian PGS (2 >> 1) transcripts, proteins, and activity on IL-1. The effects of IL-1 proved relatively specific, contingent upon somatic cell-cell cooperation, dose and time dependent, and IL-1 receptor mediated. These results are compatible with the proposition that the PG-promoting property of IL-1 is due, in large measure, to the activation of ovarian PGS transcription and translation. The ability of IL-1 to up-regulate ovarian PGS, an obligatory component of ovulation, is in keeping with the idea that IL-1 may constitute an intermediary in the ovulatory process.