Optimizing the process of fertility preservation in pediatric female cancer patients - a multidisciplinary program.

BACKGROUND: Current evidence indicates sub-optimal incidence of fertility preservation (FP) in eligible patients. We present herein our designated multidisciplinary program for FP in pediatric and adolescent population and present our data on FP in female patients. METHODS: Pediatric patients (age 0-18) who were candidate for highly gonadotoxic treatments were referred to FP program for a multidisciplinary discussion and gonadal risk-assessment followed by either oocyte cryopreservation or ovarian cryopreservation (OCP) for female patients, and sperm banking for male patients. The OCP protocol consists of aspiration of oocytes from small antral follicles and in-vitro maturation followed by cryopreservation, as well as ovarian tissue cryopreservation. RESULTS: The establishment of a designated FP program resulted in a significant increase in referral and subsequent FP procedures of all eligible patients. Sixty-two female patients were referred for FP discussion during a period of 36 months; 41 underwent OCP; 11 underwent oocyte cryopreservation and six were declined due to parental decision. The median age was 13.2y (range 18 months-18y). Thirty-two (51.6 %) were chemotherapy-naïve. Seventeen patients (27 %) had sarcoma, 16 patients (26 %) had acute leukemia. The mean number of mature oocytes that were eventually vitrified was significantly higher in chemotherapy-naïve patients compared with chemotherapy-exposed patients (mean 12 oocytes (1-42) versus 2 (0-7)). CONCLUSION: Multidisciplinary programs that encompass experts of all relevant fields, skilled laboratory resources and a facilitated path appear to maximize the yield. We observed a considerable higher referral rates following launching a designated program and earlier OCP in chemo-naïve patients that culminated in a better fertility preservation procedure.

Dialysis nurses for palliative care.

The palliative approach offers significant and practical care throughout the treatment of the dialysis patient until death. Varied aspects of quality of life for patients can be improved. It is possible to relieve symptoms such as sleep disorders, pain, constipation and pruritus, which, according to the present survey, are common symptoms. The treatment of dying dialysis patients or the possibility and legitimization of discontinuing treatment are complex, controversial issues with ethical and legal implications. But these issues have not yet been adequately dealt with by the nephrological community. The nurses who encounter patients daily, who constantly deal with great suffering and who lack tools to help, can lead the practice in this field within the framework of inter-disciplinary team work. In light of the obvious need for progress in this area, appropriate training courses should be considered. The implementation of the palliative approach in dialysis units could be a challenge for all of us in the coming years.

Beta-aminopropionitrile treatment can accelerate recovery of mice after spinal cord injury.

Modulations of the extracellular matrix and scar formation following central nervous system (CNS) injuries are considered prohibitive for axon regeneration, thus restricting functional recovery. Recent findings indicating that lysyl oxidase, an extracellular matrix-forming enzyme, appears in a time-dependent manner at brain injury sites have suggested that inhibition of this enzyme may be conducive for regeneration and functional recovery. Here, we report that after unilateral spinal cord transection in adult mice, daily treatment (for 20 days) with the lysyl oxidase inhibitor beta-aminopropionitrile (100 mg/kg intraperitoneal) resulted in accelerated and more complete functional recovery. The mode of functional recovery, however, indicates that axonal regeneration of long descending tracts did not occur.

Lysyl oxidase, the extracellular matrix-forming enzyme, in rat brain injury sites.

Lysyl oxidase is an extracellular enzyme that catalyzes cross-linkages of extracellular matrix proteins. We hypothesized that this enzyme is secreted by cells attracted to central nervous system injury sites and is involved in extracellular matrix modulation and in scar formation. Specific antibodies for immunohistochemistry and enzyme activity measurements were used to detect the presence of lysyl oxidase after longitudinal knife cuts in adult rat forebrain. Immunoreactivity was observed within the core of injury sites from 1 and up to 30 days postoperative, with less staining at 2 and 5 days, and was not associated with glial fibrillary acidic protein-positive astrocytes. Enzyme activity increased transiently in injury site regions with a peak (200% of control) at 10 days postoperative. These results are the first to provide evidence for a time-dependent appearance of active extracellular lysyl oxidase in brain injury sites. They imply that enzyme molecules are synthesized and secreted by cells attracted to brain injury sites and participate in extracellular matrix modulation.

The polyamine stress response: tissue-, endocrine-, and developmental-dependent regulation.

Transient alterations in polyamine (PA) metabolism, termed the polyamine stress response (PSR), constitute a common cellular response to stressful stimuli. In contrast to the adult brain and liver, the PSR in the adrenal gland and thymus is characterized by a reduction in PA metabolism. The brain PSR undergoes an early postnatal period of non-responsiveness. The aim of the present study was twofold: i) to determine whether the PSR in the liver, thymus, and adrenal gland is developmentally regulated as that in the brain and ii) to establish whether neuronal and hormonal signals can activate the PSR independently. Ornithine decarboxylase (ODC) activity and tissue PA concentrations served as markers of the PSR. Changes were measured in male Wistar rats during postnatal development and at 2 weeks after adrenalectomy in adults. Unlike the brain, the direction of the PSR in peripheral organs did not undergo developmental changes. After adrenalectomy, the PSR was not activated in the thymus and liver by acute (2-hr) restraint stress, but a characteristic PSR was induced in the hippocampus. However, dexamethasone injection (3 mg/kg) did induce a characteristic PSR in all organs of adrenalectomized rats. The results justify the following conclusions: i) Unlike peripheral organs, the PSR in the brain is developmentally regulated; ii) The developmental switch to a mature PSR in the brain corresponds in time to the cessation of the "stress hypo-responsive period" in the hypothalamic-pituitary-adrenocortical (HPA) axis; iii) In the periphery, the PSR appears to be dependent principally on stress-induced activation of the HPA axis and on increased circulating glucocorticoid concentrations rather than on neuronal activation; iv) In the brain, however, the PSR can be induced independently by glucocorticoids or by direct activation of the neuronal circuitry; and v) up-regulation of the PSR, as in the brain and liver, is constructive and may be implicated in cell survival, while its down-regulation, as in the adrenal and thymus, may be implicated in cell death.

Accelerated functional recovery and neuroprotection by agmatine after spinal cord ischemia in rats.

Treatment with agmatine, decarboxylated arginine, proved to be non-toxic and to exert neuroprotective effects in several models of neurotoxic and ischemic brain and spinal cord injuries. Here we sought to find out whether agmatine treatment would also prove beneficial in a rat spinal cord ischemia model (balloon occlusion of the abdominal aorta bellow the branching point of the left subclavian artery for 5 min). Agmatine was injected (100 mg/kg, i.p. ) 5 min after beginning of re-perfusion and again once daily for the next 3 post-operative days. Motor performance ('combined motor score') was recorded for up to 17 days post-operative and motoneuron cell counts (in representative spinal cord sections) performed on the 17th post-operative day. Agmatine treatment was found to accelerate recovery of motor deficits and to prevent the loss of motoneurons in the spinal cord after transient ischemia. Together, the present and previous findings demonstrate that agmatine is an efficacious neuroprotective agent and that this naturally occurring non-toxic compound should be tried for therapeutic use after neurotrauma and in neurodegenerative diseases.

Different effects of acute neonatal stressors and long-term postnatal handling on stress-induced changes in behavior and in ornithine decarboxylase activity of adult rats.

A transient increase in brain polyamine (PA) metabolism, termed the PA-stress-response (PSR), is a common response to stressful stimuli. Previous studies have implicated the PSR as a component of the adaptive and/or maladaptive brain response to stressful events. Ample evidence indicates that stressful experiences during early life can alter normal developmental processes and may result in pathophysiological and behavioral changes in the adult. The aim of the present study, therefore, was to determine whether strong acute neonatal stressors (3 mg/kg dexamethasone, or 2 h restraint stress at day 7), as compared to mild long-term intermittent maternal separation and handling (15 min, twice a day between postnatal days 2 and 25), would lead in adult Wistar rats to different PSR and behavioral reactivity to novelty stress. Changes in ornithine decarboxylase (ODC) activity and in tissue PA concentrations served as markers of the PSR, and behavioral alterations in an open-field arena indicated the reactivity to novelty stress. Animals subjected to acute neonatal stressors, showed reduced behavioral reactivity in the open-field test, indicative of increased emotional reactivity to novelty. In these animals, the increase in ODC activity after dexamethasone challenge was attenuated in the brain, but exaggerated in the liver. In the thymus and adrenal gland of these animals, the basal enzyme activity was significantly increased, but a similar reduction was observed after dexamethasone challenge. In contrast, long-term postnatal handling led in adults to novelty-induced changes indicative of reduced emotional behavior, yet the alterations in ODC activity after dexamethasone challenge in these animals were similar to those in animals after acute stressors. The concentrations of tissue polyamines in adults were not affected by any of the postnatal stressors. The results justify the following conclusions: (1) Strong acute neonatal stressors can lead to increased emotional behavior in adults, while mild long-term intermittent handling, may result in adaptation and reduced emotionality. (2) Attenuated stress-induced increase of ODC activity in the brain, but exaggerated increased activity in the liver, may be implicated in altered emotional behavior reactivity to stressors.

Novel polyamine derivatives as neuroprotective agents.

The induction of an early increase in polyamine metabolism, termed "the polyamine response," is now recognized to have a critical role in the reaction of neurons to injury. Several studies in experimental animals have demonstrated that treatment with the naturally occurring polyamines spermine, spermidine, and putrescine can protect neurons from dying after the infliction of various types of neurotrauma, including mechanical injuries, neurotoxic insults, and ischemia. These findings led us to synthesize a series of polyamine derivatives of 1-aminoindan and 1-aminotetralin and to determine their effects in several in vitro and in vivo models of neurotrauma. Some of the novel compounds proved to be potent neuroprotective in these models, and one of them, N, N-di-(4-aminobutyl)-1-aminoindan, was superior to the others and to the natural polyamines themselves. We conclude that compounds based on the novel polyamine-based structures we synthesized have therapeutic potential as neuroprotective agents.

The course of putrescine immunocytochemical appearance in neurons, astroglia and microglia in rat brain cultures.

Putrescine, the diamine precursor for polyamine biosynthesis, is a ubiquitous molecule normally present at low concentration in quiescent cells. During development, or after traumatic stress, putrescine concentrations are greatly increased. Here we describe the localization of putrescine by fluorescence immunocytochemistry in primary cultures of embryonic rat brain using specific antibodies. Antibodies against putrescine conjugated to keyhole limpet hemocyanin (KLH) were produced in rabbits. The antisera were adsorbed on KLH affinity columns and the specificity of the antibodies was assessed by inhibition enzyme-linked immunoassays (ELISA). The cellular localization paralleled the temporal sequence of appearance and disappearance of the different cell types in these mixed cultures. During the first 3 days after plating the antibodies were localized mainly in neurons. As the neurons disappeared the localization was mainly in the growing astroglia, and then, as astroglia reached confluence between 10 and 14 days in vitro, labeled astroglia were diminished in numbers while the number of labeled microglia was greatly increased. The subcellular localization was prominent in the perinuclear region of the cytoplasm. The results indicate that antibodies to KLH-conjugated putrescine can be used for immunocytochemical studies of changes in putrescine concentrations during development and after traumatic injuries.

Developmental regulation of the brain polyamine-stress-response.

A transient increase in brain polyamine metabolism, termed the polyamine-stress-response is a common response to stressful stimuli. Previous studies have implicated an over-reactive polyamine response as a component of the maladaptive brain response to stressful events, and as a novel molecular mechanism involved in the pathophysiology of affective disorders. Ample evidence indicates that stressful experiences during early life can alter normal developmental processes and may result in pathophysiological and behavioral changes in the adult. Additionally, an important characteristic of affective disorders is their age dependency, a phenomenon that may be correlated with a maladaptive regulation of the hypothalamic-pituitary-adrenocortical (HPA) neuroendocrine system. In the present study we measured the activities of the enzymes ornithine decarboxylase and S-adenosylmethionine decarboxylase as markers of polyamine synthesis and found that unlike adults, immature rats do not show the characteristic brain polyamine-stress-response. Instead of the characteristic increase observed in adults, ornithine decarboxylase activity in immature animals was reduced or remained unchanged (for up to 16 days of age) after a dexamethasone injection or restraint stress application. The ontogenesis of this ornithine decarboxylase response was brain region-specific, indicating its dependence on the stage of neuronal maturation. Animals treated with dexamethasone at 7 days of age, showed increased behavioral reactivity in the open-field test as adults and an attenuated increase in ornithine decarboxylase activity after a re-challenge with dexamethasone at age 60 days. The results indicate that: (1) the brain polyamine-stress-response is developmentally regulated and its ontogenesis is brain region-specific, indicating dependence on the stage of neuronal maturation; (2) the switch to a mature polyamine-stress-response pattern coincides with the cessation of the stress hyporesponsive period in the HPA system: (3) activation of the polyamine-stress-response, as in the mature brain, appears to be a constructive reaction, while its down-regulation, as in the developing brain, may be implicated in neuronal cell death; (4) an attenuated dexamethasone-induced increase in ornithine decarboxylase activity implicates an altered polyamine-stress-response in the maladaptive response of the brain to stressful events.

Brain polyamine stress response: recurrence after repetitive stressor and inhibition by lithium.

We recently demonstrated that, unlike in peripheral tissues, the increase in activity of polyamine synthesizing enzymes observed in the brain after acute stress can be prevented by long-term, but not by short-term, treatment with lithium. In the present study we sought to examine the effects of chronic intermittent stress on two key polyamine synthesizing enzymes, ornithine decarboxylase and S-adenosylmethionine decarboxylase, and their modulation by lithium treatment. Adult male rats were subjected to 2 h of restraint stress once daily for 5 days and to an additional delayed stress episode 7 days later. Enzyme activities were assayed 6 h after the beginning of each stress episode. In contrast to the liver, where ornithine decarboxylase activity was increased (300% of the control) only after the first stress episode, the enzyme activity in the brain was increased after each stress episode (to approximately 170% of the control). Unlike ornithine decarboxylase activity, S-adenosylmethionine decarboxylase activity was slightly reduced after the first episode (86% of the control) but remained unchanged thereafter. After cessation of the intermittent stress period, an additional stress episode 7 days later led again to an increase in ornithine decarboxylase activity in the brain (225% of the control) but not in the liver, whereas S-adenosylmethionine decarboxylase activity remained unchanged. The later increase in ornithine decarboxylase activity was blocked by lithium treatment during the intervening 7-day interval between stressors. The results warrant the following conclusions: (a) Repetitive application of stressors results in a recurrent increase in ornithine decarboxylase activity in the brain but to habituation of this response in the liver. (b) This brain polyamine stress response can be blocked by long-term (days) lithium treatment. (c) The study implicates an overreactive polyamine response as a component of the adaptive, or maladaptive, brain response to stressful events and as a novel molecular target for lithium action.

Arginine and ornithine decarboxylation in rodent brain: coincidental changes during development and after ischemia.

Agmatine, product of arginine decarboxylation, is known to occur mainly in bacteria and plants where it serves as a precursor for the synthesis of polyamines. Recently however, agmatine and arginine decarboxylation were detected in mammalian brain. Here we examined changes in rodent brain arginine decarboxylation during cerebellum development and after global forebrain ischemia and compared them to changes in ornithine decarboxylase, the enzyme catalyzing the first limiting step in polyamine synthesis. The findings suggest that (1) arginine decarboxylation is transiently increased during development and after ischemia in parallel to ornithine decarboxylase activity. (2) Arginine decarboxylation reaction is catalyzed by ornithine decarboxylase. (3) Decarboxylation of both ornithine and arginine becomes more pronounced in membrane fractions, rather than in the cytosol, during brain maturation. (4) During development, ornithine decarboxylase activity is reduced in the cytosol, but increased in the membrane fractions.

Metabolism of agmatine into urea but not into nitric oxide in rat brain.

Agmatine is a guanidino compound abundant in bacteria and plants where it serves as a precursor for polyamine synthesis. It can interfere with several neurotransmission-related functions and can exert neuroprotective effects after brain injury. Agmatine was recently identified in mammalian brain and its synthesis by arginine decarboxylation was characterized. Its metabolism by the brain is, however, unknown. Here we report evidence indicating that agmatine can be selectively metabolized in the rat brain (cerebellum) into urea and thus, may lead to formation of putrescine, the precursor of polyamine synthesis. In addition, while agmatine can inhibit brain nitric oxide synthase, it did not serve as a substrate for nitric oxide formation.

Accelerated recovery following polyamines and aminoguanidine treatment after facial nerve injury in rats.

Accelerated axon regeneration is of paramount importance for improved functional recovery after motor nerve injuries. Following injury of their axon neurones undergo a series of changes, termed the axon reaction, aimed at survival and regeneration of a new axon. We and others have found that early treatment with exogenous polyamines can enhance neuronal survival and accelerate the rate of axon regeneration and functional recovery after sympathetic and motor (sciatic) nerve injuries. Results of the present study corroborate the previous findings and demonstrate that after facial nerve injury in adult rats, polyamine treatment can accelerate the early phases of motor function recovery (vibrissae movement). Treatment with aminoguanidine, an inhibitor of several oxidation reactions, produced a further improvement at the early phase of functional recovery. In the facial nucleus, the injury-induced transient reduction in the activity of the acetylcholine synthesizing enzyme choline acetyltransferase was not affected by the treatment. After nerve injury in 5-day-old male rats, polyamines and aminoguanidine treatment exerted a minor neuroprotective effect (127.6% surviving neurones compared to control). We conclude that polyamines and aminoguanidine may have therapeutic potential in the acceleration of recovery after nerve injuries.

Delivery of the very low birthweight breech: what is the best way for the baby?

A retrospective analysis was done to determine whether vaginally vs. cesarean section-born breech infants in the very low birthweight range are at increased risk for morbidity and mortality. Eighty-three viable singleton breech infants weighing 700-1,600 g, who were delivered in our medical center during the period 1980 through 1993, were followed for up to 5 years of age. Analysis of data after correction for weight, gestational age and other confounding variables such as antepartum complications revealed that survival rates in the 700-1,000 g group were similar in both routes of delivery. In the 1,001-1,600 g group, survival rate was 60.9% after vaginal delivery, as compared to 100% after cesarean section (P < 0.01). No difference was demonstrated in long-term outcome between the vaginal and cesarean groups, although the population was too small to draw statistical conclusions. Considering the limitation of such a retrospective analysis, our data identified a trend that supports prophylactic cesarean section in cases of pre-term breech infants weighing 1,000-1,600 g.

Agmatine treatment is neuroprotective in rodent brain injury models.

Agmatine is a naturally occurring guanidino compound, found in bacteria and plants, with several proposed nervous system-related functions suggestive of beneficial effects in central nervous system injury. Here evidence is presented that agmatine can exert potent neuroprotection in both in vitro and in vivo rodent models of neurotoxic and ischemic brain injuries. The cumulative evidence lead us to suggest that agmatine, a relatively nontoxic compound, be tried for potential therapeutic use after neurotrauma and in neurodegenerative disorders.

Chemotaxis and accumulation of nerve growth factor by microglia and macrophages.

Astrocytes and microglia play a critical role in the reaction of the central nervous system (CNS) to trauma. Although both astrocytes and microglia can produce it, accumulation of immunoreactive nerve growth factor (the prototype neurotrophin important for the survival of several classes of neurons) was observed selectively in cultured microglia and macrophages, rather than in astrocytes. Furthermore, microglia were found to display chemotaxis toward a localized source of nerve growth factor and, as demonstrated by autoradiography, take up extracellular nerve growth factor. These findings suggest that microglia, the brain's own macrophages, participate in the regulation of nerve growth factor availability in a site-specific manner. This novel function may assume a general importance both in the CNS and the peripheral nervous system at critical times after trauma when this neurotrophin is needed for nerve cell survival.