Predictors of recurrence following laparoscopic radical hysterectomy for early-stage cervical cancer: A multi-institutional study.

OBJECTIVE: To assess predictors of recurrence following laparoscopic radical hysterectomy (LRH) for apparent early stage cervical cancer (CC). METHODS: This is a retrospective multi-institutional study reviewing data of consecutive patients who underwent LRH for FIGO 2009 stage IA1 (with lymphovascular space invasion (LVSI)), IA2 and IB1(≤4 cm) CC, between January 2006 and December 2017. The following histotypes were included: squamous, adenosquamous, and adenocarcinoma. Multivariable models were used to estimate adjusted odds ratio (OR) and corresponding 95% CI. Factors influencing disease-free survival (DFS) and disease-specific survival (DSS) were also explored. RESULTS: 428 patients were included in the analysis. With a median follow-up of 56 months (1-162) 54 patients recurred (12.6%). At multivariable analysis, tumor size (OR:1.04, 95%CI:1.01-1.09, p = .02), and presence of cervical residual tumor at final pathology (OR: 5.29, 95%CI:1.34-20.76, p = .02) were found as predictors of recurrence; conversely preoperative conization reduced the risk (OR:0.32, 95%CI:0.11-0.90, p = .03). These predictors remained significant also in the IB1 subgroup: tumor size: OR:1.05, 95%CI:1.01-1.09, p = .01; residual tumor at final pathology: OR: 6.26, 95%CI:1.58-24.83, p = .01; preoperative conization: OR:0.33, 95%CI:0.12-0.95, p = .04. Preoperative conization (HR: 0.29, 95%CI: 0.13-0.91; p = .03) and the presence of residual tumor on the cervix at the time of surgery (HR: 8.89; 95%CI: 1.39-17.23; p = .01) independently correlated with DFS. No independent factors were associated with DSS. CONCLUSIONS: In women with early stage CC the presence of high-volume disease at time of surgery represent an independent predictor of recurrence after LRH. Conversely, preoperative conization and the absence of residual disease at the time of surgery might play a protective role.

Maternal intra- and postpartum near-miss following assisted reproductive technology: a retrospective study.

OBJECTIVE: To assess whether risk of severe maternal morbidity at delivery differs for women who conceived using assisted reproductive technology (ART), compared with those with a spontaneous conception. DESIGN: A cohort study using a prospectively maintained institutional database. SETTING: A tertiary university maternity hospital. POPULATION: All women delivering at Del Ponte Hospital, Italy, between 2005 and 2016. METHODS: Data from 650 ART-conceived pregnancies were compared with 22 803 spontaneously conceived pregnancies. We used multivariable analysis to estimate the odds of severe maternal morbidity at delivery associated with ART conception, adjusting for maternal demographic and health factors, gestational age, and mode of delivery. MAIN OUTCOME MEASURES: The World Health Organization criteria for potentially life-threatening conditions and near-miss maternal mortality were used. RESULTS: The incidence of near-miss in the entire cohort was 3.3 cases per 1000 births (95% confidence interval, 95% CI, 2.6-4.1). The crude prevalences of potentially life-threatening conditions and maternal near-miss were higher among ART than among non-ART deliveries (27.1 versus 5.7% and 2.6 versus 0.3%, respectively). The three most common causes of maternal near-miss cases were peripartum hysterectomy, transfusion of ≥5 units of red blood cells, and cardiovascular dysfunction requiring vasoactive drugs. The odds of a maternal near-miss at delivery were increased for ART-conceived pregnancies compared with non-ART-conceived pregnancies (adjusted odds ratio, aOR 3.61, 95% CI 1.61-8.09, for ART-conceived pregnancies with autologous oocytes; aOR 13.57, 95% CI 5.45-33.77, for ART pregnancies conceived with donor oocytes). CONCLUSION: Although we cannot exclude unmeasured confounding, we found that pregnancies conceived via ART, especially those conceived with donor oocytes, are at increased risk of maternal potentially life-threatening conditions and near-miss at delivery. FUNDING: This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. TWEETABLE ABSTRACT: Conceiving through assisted reproductive technology increases the likelihood of maternal near miss.

[Decision-making regarding treatment limitation after severe traumatic brain injury: A survey of French neurosurgeons]. / Modalités de décision de limitation thérapeutique chez les traumatisés crâniens sévères : enquête auprès des neurochirurgiens en France.

BACKGROUND/INTRODUCTION: In France, the law defines and prohibits "unreasonable obstinacy" and provides a framework for the subsequent decision to limit or to cease treatment. It also gives the person the right to appoint a trusted person and to draft advance directives regarding this issue. There have been few studies of neurosurgeons' involvement in decision-making in regard to treatment limitation after severe traumatic brain injury. AIM OF THE STUDY: The first aim of the study was to assess French neurosurgeons' adherence to the law on patients' rights and end of life which governs such decision-making. The second aim was to assess the prognostic and decision-making criteria applied by neurosurgeons. METHODS: A declarative practice and opinion survey, using a self-administered questionnaire emailed to all practising neurosurgeons members of the French Society of Neurosurgery, was conducted from April to June 2016. RESULTS: Of the 197 neurosurgeons contacted, 62 filled in the questionnaire. Discussions regarding treatment limitation were in all cases collegial, as required under the law, and the patient's neurosurgeon was always involved. The trusted person and/or family were always informed and consulted, but their opinions were not consistently taken into account. Advance directives were most often lacking (68%) [56; 80] or inappropriate (27%) [16; 38]. The most frequently used prognostic criteria were clinical parameters, intracranial pressure, cerebral perfusion pressure, and imaging, with significant interindividual variation in their use. The main decision-making criteria were foreseeable disability, expected future quality of life, and age. CONCLUSIONS: Neurosurgeons showed good compliance with legal requirements, except in the matter of calling for the opinion of an external consultant. Furthermore, this survey confirmed variability in the use of prognosis predictors, and the need for further clinical research so as to achieve more-standardized practices to minimise the subjectivity in decision-making.

Intraoperative identification of the negative motor network during awake surgery to prevent deficit following brain resection in premotor regions.

INTRODUCTION: Surgical resection in premotor areas can lead to supplementary motor area syndrome as well as a permanent deficit. However, recent findings suggest a putative role of the negative motor network in those dysfunctions. Our objective was to compare the functional results in two groups of adult patients who underwent the resection of a frontal glioma with and without resection of the negative motor networks. MATERIAL AND METHODS: Twelve patients (total of 13 surgeries) were selected for awake surgery for a frontal glioma. Negative motor responses were monitored during surgery at the cortical and subcortical levels. Sites eliciting negative motor responses were first identified then spared (n=8) or removed (n=5) upon oncological requirements. RESULTS: In the group with removal of the negative motor network (n=5), all patients presented a complete supplementary motor area syndrome with akinesia and mutism. At 3months, they all presented bimanual coordination dysfunction and fine movement disorders. In the group with preservation of the negative motor network (n=8), all patients presented transient and slight disorders of speech or upper limb, they all recovered completely at 3months. DISCUSSION: The negative motor network is a part of a modulatory motor network involved in the occurrence of the supplementary motor area syndrome and the permanent deficit after resection in premotor areas. Then, intraoperative functional cortico-subcortical mapping using direct electrostimulation under awake surgery seems mandatory to avoid deficit in bimanual coordination and fine movements during surgery in premotor areas.

[Imaging follow-up of post-traumatic myelomalacia]. / Evolution d'une myelomalacie post-traumatique vers une syringomyelie: suivi iconographique.

The authors report a case of secondary worsening of neurological symptoms in a patient 2 months after cord injury at T5 causing paraplegia. The MRI showed myeolomalacia, which appears as cord oedema, located in the grey matter, extending increasingly from the initial lesion (eighth thoracic vertebra) to the bulb. This cord lesion known as grey matter cytotoxic oedema, evolved into a syringomyelic cavity.

[Childhood diencephalic pilocytic astrocytoma. A review of seven observations]. / Les astrocytomes pilocytiques du diencephale de l'enfant. à propos de sept observations.

BACKGROUND AND PURPOSE: Pilocytic astrocytoma (PA) is a WHO grade I tumor of the central nervous system mostly arising in children and young adults. Management of diencephalic PA is a difficult challenge. Surgical treatment has to cope with both the difficulties of deep location and eloquent area tumors. MATERIALS AND METHODS: We retrospectively reviewed seven pediatric cases (female: 4, male: 3) of diencephalic PA. Opto-chiasmatic tumors were excluded from the series. Mean age at diagnosis was 108 months (9 years) (range: 4 month-18 years), median age was 111 months. Median follow-up for the series was 125 months. Tumor locations were as followed: right thalamus: 2, both thalami: 1, hypothalamus: 3, and right basal ganglia: 1. At the onset, the first symptom was mostly raised intracranial pressure. The delay in diagnosis ranged from 48 hours up to 6 years. TREATMENT: a shunting procedure was performed in 3 patients, a direct surgical approach in 5 patients (gross total removal: 2; partial removal: 3) and one patient had only a biopsy. Three children were re-operated. Three patients were treated by radiationtherapy (RT) after surgery. Chemotherapy was delivered for 4 children. RESULTS: The overall survival rate was 71.4 months (almost 6 years) (range: 3-184 months). Median survival rate was 42 months (3.5 years). Three children died, two by tumor progression and one death related to late side-effects of RT. Four patients have a good quality of life with GOS I (n = 3) or II (n = 1). We observed tumor regression in two patients at 1 and 17 years after the beginning of treatment. Correct diagnosis was only made for two cases at the initial pathological examination. CONCLUSION: The course of diencephalic PA is still unpredictable. The tumor can be controlled by a partial surgical removal, and a residual tumor can sometimes decrease in size after surgery. Gross total removal of these tumors, although difficult, may be performed. With cranial navigation systems, the risk is low. Pathological diagnosis is sometimes difficult to assess.

[Subdural empyema in children: therapeutic strategy. Five cases]. / Empyèmes sous-duraux de l'enfant: stratégie thérapeutique. A propos de cinq cas.

We report a series of five subdural empyema (SDE) in children and young adults treated in the same neurosurgical department. These five cases were reviewed retrospectively. There were four boys and one girl, aged from three months to 18 years at time of diagnosis (median age: 7 years). SDE following intracranial surgery were excluded from the study. All patients were treated surgically (burr hole evacuation or craniotomy, repeated in some cases), followed by intravenous antibiotic therapy (mean time: 52 days) adapted to the micro-organism. Only the two patients treated by large craniotomy at first had a single surgical procedure. Involved micro-organisms are as follow: Streptococcus intermedius (n=2), Streptococcus pneumoniae (n=1), Escherichia coli (n=1), absence of any identified micro-organism (n=1). The five patients are alive (median follow-up: 22 month) without any sequelae. We advocate an aggressive surgical treatment of SDE in children with a large bone flap to allow the surgeon to remove pus and membranes as much as possible, even in the interhemispheric fissure, followed by intravenous appropriate antibiotherapy and eradication of the source of infection. Even this "aggressive" treatment may sometimes not avoid re-operation. A careful follow-up is mandatory, because of the high risk of recurrence.

Distribution of gonadotropin-releasing hormone immunoreactivity in the brain of Ichthyophis beddomei (Amphibia: Gymnophiona).

From a comparative viewpoint, we have investigated the presence and neuroanatomical distribution of gonadotropin-releasing hormone (GnRH)-immunoreactive material in the brain of a gymnophione amphibian, Ichthyophis beddomei. Immunocytochemical analysis of the adult brain and terminal nerves in both sexes shows the presence of neurons and fibers containing mammalian GnRH (mGnRH)- and chicken GnRH-II (cGnRH-II)-like peptides. With respect to GnRH-immunoreactive material, there are two distinct neuronal systems in the brain: one containing mGnRH, which is located in the forebrain and terminal nerve, and the other containing cGnRH-II, which is restricted to the midbrain tegmentum. Basically, this distribution pattern parallels that of many species of anurans and a urodele. Whereas the presence of cGnRH-II-immunoreactive fibers in the dorsal pallium of L. beddomei is a feature in common with a urodele amphibian, the total absence of cGnRH-II-like material in the median eminence is unique to this species. It is suggested here that the distribution profile of GnRH-like material within the brain and terminal nerve of I. beddomei represents a primitive pattern.

Ontogeny of pituitary adenylate cyclase-activating polypeptide (PACAP) in the frog (Rana ridibunda) tadpole brain: immunohistochemical localization and biochemical characterization.

The anatomic distribution and biochemical characteristics of the neuropeptide pituitary adenylate cyclase-activating polypeptide (PACAP) were investigated in the central nervous system of the frog, Rana ridibunda, during development. Three to four days after hatching, at stages IV-VII, PACAP-immunoreactive perikarya were detected in the dorsal thalamus within the anterior ventral area, and a few fibers were found in the medial pallium. Positive cell bodies were first observed in the hypothalamus at stages VIII-IX, at the level of the dorsal and ventral infundibular nuclei. In these regions, the number of positive perikarya increased during ontogeny. In tadpoles, during the mid- and late premetamorphosis, a more complex organization of the PACAP-immunoreactive system was found in the thalamus with the appearance, at stages IX-XII, of two additional groups of positive neurons in the ventrolateral area and posterocentral nucleus. At stages XIII-XVIII of larval development and subsequent larval stages, PACAP-immunoreactive fibers were found in the median eminence. In newly metamorphosed animals, several additional groups of positive perikarya appeared in the medial pallium, the preoptic nucleus, the torus semicircularis, the tegmentum of the mesencephalon, and the cerebellum. The immunoreactive peptide contained in the tadpole brain was characterized by high performance liquid chromatography analysis combined with radioimmunoassay quantification. At all stages investigated, the predominant form of PACAP-immunoreactive material coeluted with synthetic frog PACAP38. The occurrence of PACAP soon after hatching indicates that the peptide may exert neurotrophic activities. The existence of immunoreactive elements in several thalamic regions at mid- and late premetamorphic stages suggests that PACAP may act as a neurotransmitter, neuromodulator, or both, during ontogenesis. Finally, the presence of PACAP-immunoreactive perikarya in hypothalamic nuclei and nerve fibers in the median eminence supports the view that PACAP may play a role in the control of pituitary hormone secretion during larval development.

Distribution of FMRFamide-like immunoreactivity in the amphibian brain: comparative analysis.

FMRFamide is a small neuropeptide present in particular neurons of the basal forebrain and midbrain of the vertebrate groups studied, especially fishes and mammals. In order to assess interspecies variation, the distribution of FMRFamide-like immunoreactivity was studied in the brains of 13 species of amphibian. Although FMRFamide-immunoreactive (IR) terminals occurred throughout much of the brain, IR cell groups were noted in circumscribed regions of the CNS. In the eight anuran species studied, two major populations of labeled perikarya were observed: one in the septopreoptic area and another one in the caudal portion of the diencephalon. The rostrocaudal extent of both and the number of labeled somata in each neuronal group displayed species-specific differences. In urodeles and gymnophiones, labeled perikarya were located in the diencephalon, but there were remarkable species differences in the number of such cells. It is discussed whether sex or season of collection may account for some of the differences observed. The distribution of FMRFamide-IR perikarya, fibers, and pathways in the brain of anurans, urodeles, and gymnophiones was compared. The existence of FMRFamide perikarya in the anterior preoptic neuropil and medial septum appeared to be a feature common to all anurans; labeled neurons in the dorsal thalamus, however, may be present only in the (viviparous) gymnophione Typhlonectes compressicauda. Cerebrospinal fluid contacting FMRFamide neuronal cell bodies and fibers were observed in each of the three taxonomic orders. The data are compared with those previously obtained for other groups of vertebrates.

Sex and reproductive status related brain content of mammalian and chicken-II GnRHs in Rana esculenta.

Mammalian and chicken-II forms of gonadotropin-releasing hormone (mGnRH and cGnRH-II, respectively) have been measured simultaneously in the brain, pituitary, and peripheral terminal nerves (nasal area tissue) of adult males and females of a representative amphibian, Rana esculenta, during the annual reproductive cycle. Whereas in the male, brain concentrations of both GnRH forms showed significant reproductive status-related fluctuations, in the female brain only cGnRH-II content showed significant changes. The highest GnRH levels were recorded just prior to breeding in both sexes. In the pituitary both GnRHs were present in all seasons. In the peripheral terminal nerves, instead, only mGnRH was detected in all seasons confirming our previous immunohistochemical data. In both sexes furthermore, the brain and pituitary mGnRH levels were consistently much higher than those of cGnRH-II and there were no sex-related differences in the brain and pituitary content of GnRHs. Seasonal changes in brain GnRH levels may correlate with plasma sex steroid levels reinforcing the postulate that sex steroids affect GnRH neuronal systems.

Development and distribution of FMRFamide-like immunoreactivity in the toad (Bufo bufo) brain.

By using immunohistochemistry, we studied the development and distribution of the FMRFamide-like immunoreactive (ir) neuronal system in the toad brain during the ontogeny. In addition to this, experimental evidence was provided to show that the rostral forebrain-located FMRFamide neurons originate in the olfactory placode and then migrate into the brain along the olfactory pathway. During early development, within the brain, FMRFamide-ir perikarya first appeared in the periventricular hypothalamus. Later in development, FMRFamide-ir cells were visualized in the rostralmost forebrain simultaneously with similar ir cells in the developing olfactory mucosa. Selective ablation of the olfactory placode(s), prior to the appearance of the first FMRFamide-ir cells in the brain, resulted in the total absence of ir cells in the telencephalon (medial septum and mediobasal telencephalon) of the operated sides(s). The preoptic-suprachiasmatic-infundibular hypothalamus-located FMRFamide-ir neurons were not affected by olfactory placodectomy, arguing that they do not originate in the placode. This result points to the placode as the sole source of such neurons in the rostral forebrain.

FMRFamide in the amphibian brain: a comprehensive survey.

Mapping of FMRFamidergic neural circuitry in the amphibian brain has been done by immunohistochemical methods. Comparative evidence suggests that there are similarities and differences in the overall pattern of distribution of FMRFamide-ir elements in the brain among the three amphibian orders and within each order. FMRFamide is expressed in neurons in some circumscribed areas of the brain. A part of these neurons is concentrated in classical neurosecretory areas of the hypothalamus in a bilaterally symmetrical fashion. Similar neurons occur occasionally in the midbrain, but are virtually absent from the hindbrain. Anurans are unique among amphibians to show FMRFamide neurons in the medial septum and diagonal band of Broca. A viviparous gymnophione is known to possess a small population of such neurons in the dorsal thalamus. Together, the FMRFamide neurons contribute to an extensive fiber network throughout the amphibian brain. Descriptive developmental studies suggest that the rostral forebrain-located FMRFamide neurons originate in the olfactory placode and then migrate into the brain along the route of the vomeronasal-olfactory-terminal nerve complex. Olfactory placodal ablation in an anuran and a urodele provide experimental support to this contention. Other FMRFamide neuronal cell groups, in the hypothalamus and dorsal thalamus, are supposed to arise from non-placodal precursors. The neuroanatomical distribution (projection of immunoreactive processes to areas of the fore-, mid-, and hindbrain as well as to cerebrospinal fluid, co-localization with other neuropeptides, and presence in the median eminence) has furnished morphological correlates of possible functions of FMRFamide in the amphibian CNS. While amphibian FMRFamide-like or structurally related peptides remain to be isolated and characterized, the sum of the distribution pattern of FMRFamide-like immunoreactivity suggests that it may act as a neurotransmitter or a neuromodulator, and also may have endocrine regulatory functions.

Neuroanatomical organization of GnRH neuronal systems in the lizard (Podarcis s. sicula) brain during development.

The ontogenesis of the GnRH neuronal systems was studied in the brain of the lizard, Podarcis s. sicula, by immunohistochemistry. The first GnRH neurons were seen in the mesencephalon on the 45th day of incubation. One week later GnRH-ir neurons appeared in the infundibulum as well. These neurons never appeared to be contiguous with midbrain GnRH neurons. Thus, the adult pattern of distribution of GnRH neurons was reached before hatching, which occurred on the 66th day of incubation at a temperature of 28 +/- 2 degrees C. Although mesencephalic and infundibular GnRH neurons and their fiber projections appeared to be distributed in anatomically distinct brain areas, both systems showed a positive reaction to chicken-I GnRH (cGnRH-I), chicken-II GnRH (cGnRH-II) and salmon GnRH (sGnRH). From the time of hatching, GnRH-ir fibers in the mesencephalon appeared to be reaching the optic tectum, tegmentum, cerebellum and rostral dorsal rhombencephalon, whereas GnRH fibers in the infundibulum were projecting to the caudal basal telencephalon, median eminence and rostral basal rhombencephalon. In 60-day-old juvenile lizards, the central area of telencephalon contained neurons reacting only with anti-cGnRH-I and anti-sGnRH. Such neurons were absent in the adult. Neither GnRH cells nor fibers were observed in the nasal area, terminal nerve and olfactory bulbs at any stage of development and in the adult. We hypothesize that the two GnRH neuronal systems have separate embryonic origins.

Distribution of vasoactive intestinal peptide-like immunoreactivity in the brain and pituitary of the frog (Rana esculenta) during development.

The localization of vasoactive intestinal peptide (VIP)-like immunoreactive (ir) elements was investigated in the brain of the anuran amphibian, Rana esculenta, during development. Using an antiserum raised against the porcine VIP, ir cell bodies and fibers were observed in the forebrain of tadpoles a few days after hatching. During early premetamorphosis, ir perikarya were distributed in the ventral infundibular nucleus of the hypothalamus and in the posterocentral nucleus of the thalamus. Labeled fibers were detected in the olfactory bulbs and in the hypothalamus. In these larvae, furthermore, several VIP-ir cells were found in the pars distalis of the pituitary and there were ir fibers in the pars nervosa. In tadpoles at stages VIII-IX, a new group of VIP-labeled neurons was observed in the dorsal part of the infundibular nucleus. In other brain regions, the distribution of the immunoreactivity was similar to that described in the earliest stages, i.e., IV-VII. During mid-premetamorphosis, stages X-XII of development, an additional set of ir perikarya appeared in the ventrolateral area of the thalamus. During late premetamorphosis, stages XIII-XVIII, the organization of VIP-like immunoreactivity was more complex and its distribution more widespread. Two new groups of ir cell bodies appeared, one in the preoptic nucleus and another in the anteroventral area of the thalamus, and for the first time, VIP immunoreactivity was observed in the median eminence. This distribution pattern persisted through to the prometamorphic, four-limb stage. Strikingly, no VIP-ir elements were observed anywhere in the mid- and hindbrain. The present results indicate that a VIP-like ir peptide may be involved in the processing of olfactory information or may act as a neurohormone, hypophysiotropic factor, and neuromodulator in the brain of R. esculenta during development.

Comparative immunocytochemical study of FMRFamide neuronal system in the brain of Danio rerio and Acipenser ruthenus during development.

The distribution of FMRFamide-like immunoreactive (ir) neurons and fibers was investigated in the central nervous system of developing zebrafish and juvenile sturgeon (sterlet). Adult zebrafish was also studied. In zebrafish embryos FMRFamide-ir elements first appeared 30 h post-fertilization (PF). Ir somata were located in the olfactory placode and in the ventral diencephalon. FMRFamide-ir fibers originating from diencephalic neurons were found in the ventral telencephalon and in ventral portions of the brainstem. At 48 h PF, the ir perikarya in the olfactory placode displayed increased immunoreactivity and stained fibers emerged from the somata. At 60 h PF, bilaterally, clusters of FMRFamide-ir neurons were found along the rostro-caudal axis of the brain, from the olfactory placode to rostral regions of the ventro-lateral telencephalon. At 60 h PF, numerous ir fibers appeared in the dorsal telencephalon, optic lobes, optic nerves, and retina. Except for ir fibers in the hypophysis at the age of 72 h PF, and a few ir cells in the nucleus olfacto-retinalis (NOR) at the age of 2 months PF, no major re-organization was noted in subsequent ontogenetic stages. The number of stained NOR neurons increased markedly in sexually mature zebrafish. In adult zebrafish, other ir neurons were located in the dorsal zones of the periventricular hypothalamus and in components of the nervus terminalis. We are inclined to believe that neurons expressing FMRFamide originate in the olfactory placode and in the ventricular ependyma in the hypothalamus. On the same grounds, a dual origin of FMRFamide-ir neurons is inferred in the sturgeon, an ancestral bony fish: prior to the observation of ir cells in the nasal area and in the telencephalon stained neurons were noted in circumventricular hypothalamic regions.

Distribution of FMRFamide-like immunoreactivity in the brain and pituitary of Rana esculenta during development.

Developmental aspects of the distribution of FMRFamide (Phe-Met-Arg-Phe-NH2) immunoreactivity (ir) were investigated by indirect immunofluorescence in the brain, pituitary and terminal nerve of the frog, Rana esculenta. Soon after hatching. FMRFamide neurons were found in the proximal terminal nerve, mediobasal olfactory bulb, caudal dorsolateral pallium, diagonal band of Broca, anterior preoptic area, suprachiasmatic area, thalamus, infundibulum, and developing pituitary. FMRFamide fibers were present in the olfactory epithelium, terminal nerve, olfactory bulbs, dorsal and midventral telencephalon, epiphysis, mediolateral thalamus, pretectal gray, optic tectum, infundibulum, posterior interpeduncular nucleus-tegmentum area, and rostral rhombencephalon. During successive developmental stages, ir neurons were no longer observed in the dorsal telencephalon and pituitary. In late larval stages, ir neurons appeared in the medial septal area, and ir fibers in the cerebellum and torus semicircularis. At the same time, the frequency of ir neurons increased progressively in the anterior preoptic area, suprachiasmatic area and infundibulum. FMRFamide-ir neurons were never revealed in mesencephalon and rhombencephalon. Numerous ir fibers terminated in the median eminence and intermediate lobe of the pituitary. The adult pattern of distribution of FMRFamide-ir elements in the brain was achieved during the postmetamorphic development. In light of the existing literature, the possible placodal origin of forebrain-located FMRFamide neurons is briefly discussed.

Development and distribution of gonadotropin-releasing hormone neuronal systems in the frog (Rana esculenta) brain: immunohistochemical analysis.

The ontogenesis of the gonadotropin-releasing hormone (GnRH) neuronal systems was studied in the brain of the frog, Rana esculenta. Attention was also focussed on the differential distribution of molecular forms of GnRH during development. The first GnRH-immunoreactive neurons appear in the mesencephalon of posterior limb-stage tadpoles. These neurons are shown to contain only chicken [His5,Trp7,Tyr8]GnRH (cGnRH-II). Later in development, mammalian [Tyr5,Leu7,Arg8] GnRH (mGnRH)-like peptide-containing neurons appear simultaneously in the terminal nerve as well as in the anterior preoptic area of the telencephalon. Subsequently, only after metamorphosis, mGnRH-containing neurons appear in the medial septal area of the posterior telencephalon. It is here shown that neurons containing the two forms of GnRH are distributed in distinct brain areas during development and in the adult: mGnRH-immunoreactive neurons in the terminal nerve, olfactory bulb, mediobasal telencephalon, medial septal area, anterior preoptic area, ventrolateral thalamus and infundibulum, whereas cGnRH-II neurons are located in the mesencephalon. We hypothesize that the terminal nerve/forebrain-located GnRH neurons express immunohistochemically late in development and originate extracranially migrating centrally, along the terminal nerve, during development, whereas those located in the mesencephalon express earlier and may have an intracranial site of origin.