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Spontaneous Recovery (spontaneous + recovery)
Selected AbstractsSpontaneous recovery of an intensively used grassland after cessation of fertilizingAPPLIED VEGETATION SCIENCE, Issue 4 2009Josef Královec Abstract Questions: (1) Does a fertilized grassland recover in terms of species composition and species richness after stopping the treatment? (2) Which species contributed most to the changes? (3) Is it realistic to rely upon spontaneous recovery in this and similar cases? Location: A large grassland, located in the western part of the Czech Republic in central Europe, latitude 49° 59,, longitude 12° 45,, altitude 750 m a.s.l. Methods: Experimental plots of 2.5 m × 6.0 m were established in the central part of the grassland in 1968 using a randomized block design with the following variants: unfertilized controls, 80, 160, 240 and 320 kg ha,1 of nitrogen, in four or eight (320 kg) replicates. The fertilization regime was stopped in 1989. Phytosociological relevés of 2 m × 4 m in size were made in 1990, 1994, 1996, 1997, 1999, 2003 and 2006. The data were processed by multivariate ordination methods (DCA, CCA). Differences in the number of species per plot were tested by repeated measures anova and Tukey's HSD test. Results: All plots, including controls, exhibited a distinct trajectory through time, reflecting the rates of fertilizer used and generally changing in the same direction. Both time and nutrients significantly influenced the vegetation pattern. Treatments differed significantly in species richness, especially at the beginning of the observation. Differences in later years were less pronounced, thus a convergence between the treatments was evident. Conclusions: During the 16 years after fertilization ceased, the number of species substantially increased not only in the fertilized plots but also in the controls. Species typical of semi-natural grasslands predominantly contributed to the increase. Spontaneous recovery after cessation of fertilizing was relatively efficient, but the fertilized plots were small in size and thus rather easily colonized from outside. For interpretation and extrapolation of results from small experimental plots, it is necessary to consider changes in the broader surroundings. [source] Glucocorticoid receptors in the basolateral nucleus of amygdala are required for postreactivation reconsolidation of auditory fear memoryEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 12 2007Xin-Chun Jin Abstract It is well known that initial consolidation requires de novo gene transcription and protein synthesis in order for memory to become stable. The consolidated memory again becomes labile and temporarily sensitive to disruption when retrieved, requiring a reconsolidation process to become permanent. Although it is well established that glucocorticoid receptors (GR) in the basolateral nucleus of amygdala (BLA) are required for consolidation of fear memory, little is known about their role in reconsolidation of fear memory. In the present study, we first examined the effect of a GR antagonist on postconditioning consolidation of auditory fear memory (AFM). Intra-BLA infusion of the GR antagonist RU486 0 h postconditioning impaired long-term AFM, leaving short-term AFM intact. RU486 had no effect if infusion was performed 6 h postconditioning. We then investigated the effect of the RU486 treatment on postretrieval reconsolidation of AFM. Severe amnesia took place when RU486 was infused into the BLA 0 h postretrieval (reactivation) of AFM, regardless of whether the retrieval was performed 1 day or 10 days postconditioning. RU486 produced no amnesia if the memory retrieval was omitted or if the drug was administered 6 h postretrieval. Treatment with RU486 0 h postretrieval produced no deficit in postretrieval short-term memory but impaired postretrieval long-term memory, and the amnesia exhibited no spontaneous recovery 6 days after retrieval. The present results provide strong evidence that glucocorticoid receptors in the BLA are required for reconsolidation as well as consolidation of AFM. [source] Sexual dimorphism in the spontaneous recovery from spinal cord injury: a gender gap in beneficial autoimmunity?EUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2002Ehud Hauben Abstract Immune cells have been shown to contribute to spontaneous recovery from central nervous system (CNS) injury. Here we show that adult female rats and mice recover significantly better than their male littermates from incomplete spinal cord injury (ISCI). This sexual dimorphism is wiped out and recovery is worse in adult mice deprived of mature T cells. After spinal cord contusion in adult rats, functional recovery (measured by locomotor scores in an open field) was significantly worse in females treated with dihydrotestosterone prior to the injury than in placebo-treated controls, and significantly better in castrated males than in their noncastrated male littermates. Post-traumatic administration of the testosterone receptor antagonist flutamide promoted the functional recovery in adult male rats. These results, in line with the known inhibitory effect of testosterone on cell-mediated immunity, suggest that androgen-mediated immunosuppression plays a role in ISCI-related immune dysfunction and can therefore partly explain the worse outcome of ISCI in males than in female. We suggest that females, which are more prone to develop autoimmune response than males, benefit from this response in cases of CNS insults. [source] Tissue inhibitor of metalloproteinases-1 attenuates spontaneous liver fibrosis resolution in the transgenic mouseHEPATOLOGY, Issue 4 2002Hitoshi Yoshiji It has been suggested that the tissue inhibitor of metalloproteinases-1 (TIMP-1) is involved in spontaneous resolution of liver fibrosis. The aim of this study was to investigate whether TIMP-1 altered spontaneous resolution of liver fibrosis in conjunction with matrix metalloproteinases (MMP) inhibition and hepatic stellate cell (HSC) activation. The livers of liver-targeted TIMP-1 transgenic (TIMP-Tg) and control hybrid (Cont) mice were harvested at 0, 3, 7, and 28 days following spontaneous recovery from CCl4 -induced liver fibrosis. The extent of fibrosis resolution, MMP expression, ,-smooth-muscle actin (,-SMA) positive cells, and procollagen-(I) messenger RNA (mRNA) in the liver were assessed at the respective periods in both groups. We also examined the effect of TIMP-1 on HSC apoptosis. The TIMP-Tg mice showed significantly attenuated resolution of spontaneous liver fibrosis compared with the Cont mice. The hydroxyproline content, number of ,-SMA positive cells, and procollagen-(I) mRNA rapidly decreased with time in the Cont mice, whereas these markers were little changed in TIMP-Tg mice. The level of the active form of metalloproteinases-2 (MMP-2) in the TIMP-Tg mice was less than that in the Cont mice. TIMP-1 markedly decreased the nonparenchyma apoptotic cells in the liver fibrosis resolution model, and it also inhibited HSC apoptosis associated with suppression of caspase-3 activity in vitro. In conclusion, TIMP-1 significantly attenuated spontaneous resolution of liver fibrosis by the combination of a net reduction of the MMP activity and suppression of apoptosis in HSC. [source] Predictive ability of propofol effect,site concentrations during fast and slow infusion ratesACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 4 2010P. O. SEPÚLVEDA Background: The performance of propofol effect,site pharmacokinetic models during target-controlled infusion (TCI) might be affected by propofol administration rate. This study compares the predictive ability of three effect,site pharmacokinetic models during fast and slow infusion rates, utilizing the cerebral state index (CSI) as a monitor of consciousness. Methods: Sixteen healthy volunteers, 21,45 years of age, were randomly assigned to receive either a bolus dose of propofol 1.8 mg/kg at a rate of 1200 ml/h or an infusion of 12 mg/kg/h until 3,5 min after loss of consciousness (LOC). After spontaneous recovery of the CSI, the bolus was administered to patients who had first received the infusion and vice versa. The study was completed after spontaneous recovery of CSI following the second dose scheme. LOC was assessed and recorded when it occurred. Adequacies of model predictions during both administration schemes were assessed by comparing the effect,site concentrations estimated at the time of LOC during the bolus dose and during the infusion scheme. Results: LOC occurred 0.97 ± 0.29 min after the bolus dose and 6.77 ± 3.82 min after beginning the infusion scheme (P<0.05). The Ce estimated with Schnider (ke0=0.45/min), Marsh (ke0=1.21/min) and Marsh (ke0=0.26/min) at LOC were 4.40 ± 1.45, 3.55 ± 0.64 and 1.28 ± 0.44 ,g/ml during the bolus dose and 2.81 ± 0.61, 2.50 ± 0.39 and 1.72 ± 0.41 ,g/ml, during the infusion scheme (P<0.05). The CSI values observed at LOC were 70 ± 4 during the bolus dose and 71 ± 2 during the infusion scheme (NS). Conclusion: Speed of infusion, within the ranges allowed by TCI pumps, significantly affects the accuracy of Ce predictions. The CSI monitor was shown to be a useful tool to predict LOC in both rapid and slow infusion schemes. [source] Glucose-dependent insulinotropic polypeptide (GIP) and its receptor (GIPR): Cellular localization, lesion-affected expression, and impaired regenerative axonal growthJOURNAL OF NEUROSCIENCE RESEARCH, Issue 8 2009Bettina A. Buhren Abstract Glucose-dependent insulinotropic polypeptide (GIP) was initially described to be rapidly regulated by endocrine cells in response to nutrient ingestion, with stimulatory effects on insulin synthesis and release. Previously, we demonstrated a significant up-regulation of GIP mRNA in the rat subiculum after fornix injury. To gain more insight into the lesion-induced expression of GIP and its receptor (GIPR), expression profiles of the mRNAs were studied after rat sciatic nerve crush injury in 1) affected lumbar dorsal root ganglia (DRG), 2) spinal cord segments, and 3) proximal and distal nerve fragments by means of quantitative RT-PCR. Our results clearly identified lesion-induced as well as tissue type-specific mRNA regulation of GIP and its receptor. Furthermore, comprehensive immunohistochemical stainings not only confirmed and exceeded the previous observation of neuronal GIP expression but also revealed corresponding GIPR expression, implying putative modulatory functions of GIP/GIPR signaling in adult neurons. In complement, we also observed expression of GIP and its receptor in myelinating Schwann cells and oligodendrocytes. Polarized localization of GIPR in the abaxonal Schwann cell membranes, plasma membrane-associated GIPR expression of satellite cells, and ependymal GIPR expression strongly suggests complex cell type-specific functions of GIP and GIPR in the adult nervous system that are presumably mediated by autocrine and paracrine interactions, respectively. Notably, in vivo analyses with GIPR-deficient mice suggest a critical role of GIP/GIPR signal transduction in promoting spontaneous recovery after nerve crush, insofar as traumatic injury of GIPR-deficient mouse sciatic nerve revealed impaired axonal regeneration compared with wild-type mice. © 2009 Wiley-Liss, Inc. [source] Molecular adsorbent recirculating system treatment for patients with liver failure: the Hong Kong experienceLIVER INTERNATIONAL, Issue 6 2006Alexander Chiu Abstract: Background: The molecular adsorbent recirculating system (MARS) is an extracorporeal liver dialysis system that allows selective removal of bilirubin and other albumin-bound toxins. We reported here our experience with the use of this technique for management of liver failure at Queen Mary Hospital, Hong Kong. Methods: From December 2002 to 2004, a total of 74 MARS sessions were performed on 22 patients. The cause of liver failure included acute liver failure (n=2), acute on chronic liver failure (n=12), posthepatectomy liver failure (n=4), and posttransplantation allograft failure (n=4). Results: MARS treatment showed significant reduction in total bilirubin level, serum ammonia level and blood urea, and nitrogen (P<0.001 for all three parameters). Five patients (22.7%) were able to bridge to transplantation and one patient (4.5%) made a spontaneous recovery. The 30-day mortality rate was 72.7%. Conclusions: Our results indicated that MARS can effectively improve serum biochemistry and is suitable for temporarily supporting patients with liver failure where transplantation is not immediately available. There is, however, no clear evidence showing that MARS can increase survival, improve the chance of transplantation or assist liver regeneration. Future studies in the form of randomized-controlled trials are crucial to characterize the true potential of this treatment. [source] Changes in the visual field following laser in situ keratomileusis for myopiaOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 2 2007Antonio Lleó-Pérez Abstract Purpose:, To assess the changes of the visual field (VF) caused by transient intraocular pressure (IOP) peaks during laser in situ keratomileusis (LASIK) surgery for myopia using automated perimetry. Methods:, This prospective study involved 94 eyes of 94 patients who underwent a conventional LASIK procedure. A complete eye examination was carried out in which the IOP measurement, and Humphrey 24-2 SITA standard VF were tested prior to LASIK and 6 and 12 months after LASIK. Patients were divided into two subgroups according to their refractive error. VF global indices, Glaucoma Hemifield Test and the number of depressed points deviating at p < 5%, p < 2%, p < 1% and p < 0.5% on the Pattern Deviation probability maps were compared using the analysis of variance. Results:, In the low myopia group, there were no significant differences in the analysed variables, except a slight decrease in mean deviation (MD) when comparing results prior to and 6 months following LASIK (p = 0.036; anova) that returned to baseline values at 12 months after surgery. In the moderate and high myopia group, there were no statistically significant differences in any of the variables analysed. No significant correlation was found between the transitory reduction in MD and any of the variables studied. Conclusions:, In patients with low myopia, the VF undergoes a transitory increase in diffuse defects 6 months after surgery, with spontaneous recovery at 12 months after LASIK procedure. Possible explanations for these findings are discussed. [source] Primary pulmonary lymphangiectasis in a premature infant: Resolution following intensive care,PEDIATRIC PULMONOLOGY, Issue 5 2003C. Scott MRCPCH Abstract Primary pulmonary lymphangiectasis is a rare disease, often described as fatal within the neonatal period. We report on an infant who developed severe bilateral chylous pleural effusions with computed tomography (CT) features of pulmonary lymphangiectasis. She recovered spontaneously with supportive treatment only. We discuss aspects of her intensive care which might have contributed to the good outcome, and conclude that modern intensive care may allow spontaneous recovery in conditions described in the literature as having a very poor outcome. Pediatr Pulmonol. 2003; 35:405,406. © 2003 Wiley-Liss, Inc. [source] Habituation of sexual response in male Heliothis mothsPHYSIOLOGICAL ENTOMOLOGY, Issue 2 2000Kevin C. Daly Summary It has been generally hypothesized that habituation mediates the effects of pheromone-based disruption strategies used in the management of moth pests. The current study demonstrates that pheromone-mediated sexual response in the tobacco budworm moth, Heliothis virescens (F.) (Lepidoptera: Noctuidae), can in fact be modulated by conditions consistent with the production of habituation. An ethogram was used to measure response strength in a wind tunnel experiment where male moths were allowed to respond freely to one of two different blends of female pheromone in 16 trials over 4 days. Post-test measures were collected to investigate stimulus specificity and long-term effects. In conditions appropriate to the formation of habituation, habituation will develop and disrupt male sexual response to female sex pheromone. Males repeatedly exposed to plumes of synthetic pheromone blends display a habituated response lasting up to 96 h. Habituation rate and spontaneous recovery of response strength are greater with less intense stimuli. Additionally, males habituated to one blend express no habituation of sexual response when exposed to a different blend. This indicates a high degree of stimulus specificity, which could facilitate outbreeding, and that moths attend to the configuration of the pheromone blend, not simply to its elements. [source] Intratympanic Dexamethasone for Sudden Sensorineural Hearing Loss After Failure of Systemic TherapyTHE LARYNGOSCOPE, Issue 1 2007David S. Haynes MD Abstract Objective: Intratympanic steroids are increasingly used in the treatment of inner ear disorders, especially in patients with sudden sensorineural hearing loss (SNHL) who have failed systemic therapy. We reviewed our experience with intratympanic steroids in the treatment of patients with sudden SNHL to determine overall success, morbidity, and prognostic factors. Hypothesis: Intratympanic steroids have minimal morbidity and the potential to have a positive effect on hearing recovery in patients with sudden SNHL who have failed systemic therapy. Study Design: The authors conducted a retrospective review. Methods: Patients presenting with sudden SNHL defined as a rapid decline in hearing over 3 days or less affecting 3 or more frequencies by 30 dB or greater who underwent intratympanic steroids therapy (24 mg/mL dexamethasone) were reviewed. Excluded were patients with Meniere disease, retrocochlear disease, autoimmune HL, trauma, fluctuating HL, radiation-induced HL, noise-induced HL, or any other identifiable etiology for sudden HL. Patients who showed signs of fluctuation of hearing after injection were excluded. Pretreatment and posttreatment audiometric evaluations including pure-tone average (PTA) and speech reception threshold (SRT) were analyzed. Patient variables as they related to recovery were studied and included patient age, time to onset of therapy, status of the contralateral ear, presence of diabetes, severity of HL, and presence of associated symptoms (tinnitus, vertigo). A 20-dB gain in PTA or a 20% improvement in SDS was considered significant. Results: Forty patients fit the criteria for inclusion in the study. The mean age of the patients was 54.8 years with a range from 17 to 84 years of age. Overall, 40% (n = 16) showed any improvement in PTA or SDS. Fourteen (35%) men and 26 (65%) women were included. Using the criteria of 20-dB improvement in PTA or 20% improvement in SDS for success, 27.5% (n = 11) showed improvement. The mean number of days from onset of symptoms to intratympanic therapy was 40 days with a range of 7 days to 310 days. A statistically significant difference was noted in those patients who received earlier injection (P = .0008, rank sum test). No patient receiving intratympanic dexamethasone after 36 days recovered hearing using 20-dB PTA decrease or a 20% increase in discrimination as criteria for recovery. Twelve percent (n = 5) of patients in the study had diabetes with 20% recovering after intratympanic dexamethasone (not significantly different from nondiabetics at 28.6%, Fisher exact test, P = 1.0). Comparison to other studies that used differing steroid type, concentration, dosing schedule, inclusion criteria, and criteria for success revealed, in many instances, a similar overall recovery rate. Conclusions: Difficulty in proving efficacy of a single modality is present in all studies on SNHL secondary to multiple treatment protocols, variable rates of recovery, and a high rate of spontaneous recovery. Forty percent of patients showed some improvement in SDS or PTA after treatment failure. When criteria of 20-dB PTA or 20% is considered to define improvement, the recovery rate was 27.5%. Modest improvement is seen with the current protocol of a single intratympanic steroid injection of 24 mg/mL dexamethasone in patients who failed systemic therapy. Dramatic hearing recovery in treatment failures was rarely encountered. No patient showed significant benefit from intratympanic steroids after 36 days when using this protocol for idiopathic sudden SNHL. If patients injected after 6 weeks are excluded from the study, the improvement rate increases from 26.9% to 39.3%. Earlier intratympanic injection had a significant impact on hearing recovery, although with any therapeutic intervention for sudden SNHL, early success may be attributed to natural history. If we further exclude seven patients treated with intratympanic steroids within 2 weeks of the onset of symptoms (i.e., study only those patients treated with intratympanic dexamethasone between 2 and 6 weeks after onset of symptoms), still, 26% improved by 20 dB or 20% SDS. The recovery rates after initial systemic failure are higher than would be expected in this treatment failure group given our control group (9.1%) and literature review. These findings indicate a positive effect from steroid perfusion in this patient population. [source] Repairing the human brain after stroke: I. Mechanisms of spontaneous recoveryANNALS OF NEUROLOGY, Issue 3 2008Steven C. Cramer MD Stroke remains a leading cause of adult disability. Some degree of spontaneous behavioral recovery is usually seen in the weeks after stroke onset. Variability in recovery is substantial across human patients. Some principles have emerged; for example, recovery occurs slowest in those destined to have less successful outcomes. Animal studies have extended these observations, providing insight into a broad range of underlying molecular and physiological events. Brain mapping studies in human patients have provided observations at the systems level that often parallel findings in animals. In general, the best outcomes are associated with the greatest return toward the normal state of brain functional organization. Reorganization of surviving central nervous system elements supports behavioral recovery, for example, through changes in interhemispheric lateralization, activity of association cortices linked to injured zones, and organization of cortical representational maps. A number of factors influence events supporting stroke recovery, such as demographics, behavioral experience, and perhaps genetics. Such measures gain importance when viewed as covariates in therapeutic trials of restorative agents that target stroke recovery. Ann Neurol 2008;63:272,287 [source] Spontaneous recovery of an intensively used grassland after cessation of fertilizingAPPLIED VEGETATION SCIENCE, Issue 4 2009Josef Královec Abstract Questions: (1) Does a fertilized grassland recover in terms of species composition and species richness after stopping the treatment? (2) Which species contributed most to the changes? (3) Is it realistic to rely upon spontaneous recovery in this and similar cases? Location: A large grassland, located in the western part of the Czech Republic in central Europe, latitude 49° 59,, longitude 12° 45,, altitude 750 m a.s.l. Methods: Experimental plots of 2.5 m × 6.0 m were established in the central part of the grassland in 1968 using a randomized block design with the following variants: unfertilized controls, 80, 160, 240 and 320 kg ha,1 of nitrogen, in four or eight (320 kg) replicates. The fertilization regime was stopped in 1989. Phytosociological relevés of 2 m × 4 m in size were made in 1990, 1994, 1996, 1997, 1999, 2003 and 2006. The data were processed by multivariate ordination methods (DCA, CCA). Differences in the number of species per plot were tested by repeated measures anova and Tukey's HSD test. Results: All plots, including controls, exhibited a distinct trajectory through time, reflecting the rates of fertilizer used and generally changing in the same direction. Both time and nutrients significantly influenced the vegetation pattern. Treatments differed significantly in species richness, especially at the beginning of the observation. Differences in later years were less pronounced, thus a convergence between the treatments was evident. Conclusions: During the 16 years after fertilization ceased, the number of species substantially increased not only in the fertilized plots but also in the controls. Species typical of semi-natural grasslands predominantly contributed to the increase. Spontaneous recovery after cessation of fertilizing was relatively efficient, but the fertilized plots were small in size and thus rather easily colonized from outside. For interpretation and extrapolation of results from small experimental plots, it is necessary to consider changes in the broader surroundings. [source] Risk for Contrast Nephropathy in Patients Undergoing CoronarographyARTIFICIAL ORGANS, Issue 6 2010Gaetano La Manna Abstract Among the causes of in-hospital acute renal failure, contrast-induced nephropathy ranks third in prevalence. Although it represents a condition of renal impairment with spontaneous recovery, contrast nephropathy should always be considered, because it prolongs hospitalization and it may become a severe complication requiring dialysis. The purposes of this study are: (i) to determine if the application of the most effective contrast-induced nephropathy prevention strategies in the Cardiology Intensive Care Unit can prove to be successful in reducing nephropathy risk; and (ii) to identify which of the involved risk factors persist after the preventive treatment. We examined the patients who had a coronarography at the Bentivoglio hospital from April 2007 to April 2008 who required at least 3 days of permanence in hospital due to the presence of potential risk factors; 136 out of 784 patients were included. Among the selected patients, 21 (15.44%) developed a renal impairment compatible with contrast-induced nephropathy. The risk factors that seemed to display the best correlation with risk of contrast nephropathy were advanced age and an ventricular failure (ejection fraction <40%); however, the critical condition did not appear to be due to a single risk factor, but it resulted from the association of more contextual risk factors. Particularly, the concomitant presence of ventricular failure, anemia, diabetes, previous myocardial infarction and advanced age (>70 years) determined a threefold increased risk of contrast nephropathy. Our data suggest that the development of contrast nephropathy following coronarography is associated with worse renal function during hospitalization and at discharge. [source] Clinical Practice of Functional Electrical Stimulation: From "Yesterday" to "Today"ARTIFICIAL ORGANS, Issue 8 2008Milan R. DimitrijevicArticle first published online: 18 AUG 200 Abstract:, Functional electrical stimulation (FES) is an accepted treatment method for paresis or paralysis after spinal cord and head injury as well as stroke and other neurological upper motor neuron disorders. At the beginning, FES worked like an electrophysiological brace for the correction of drop foot of patients after a stroke. When analyzing early accomplishments, it becomes evident that FES was influenced rather by technological and biomedical engineering development than by contemporary knowledge on neurocontrol of movement in individuals with upper motor neuron paralysis. Nevertheless, with better understanding of pathophysiology of spasticity and neurocontrol of impaired movement, FES advanced from an electrophysiological brace to a treatment modality for the improvement of muscle control, neuroaugmentation of residual movements, and supportive procedure for "spontaneous recovery" of motor control. In the present article we shall illustrate barriers which delayed FES to be applied in clinical practice of neuron rehabilitation from "Yesterday" to "Today." We shall discuss the importance to apply FES early after the onset of neurological conditions to prevent disuse of noninjured portions of the CNS. Moreover, FES can play a significant role in the supporting processes of neuroplasticity in the subacute phase of upper motor neuron dysfunction. Therefore, the electrophysiological brace of "Yesterday" provides "Today" a correction of missing neuromuscular function. At the same time, it is an active external device for the correction of motor deficits interacting with the somatosensory-motor integration. Thus, "Yesterday" and "Today" of the same technological approach can be very different, thanks to a different understanding and assessment of "external" and "internal" components of human motor control. [source] Delayed-onset neutropenia associated with rituximab therapyBRITISH JOURNAL OF HAEMATOLOGY, Issue 6 2003Kritika Chaiwatanatorn Summary. The characteristics of severe neutropenia with a delayed onset following administration of rituximab have been evaluated in 53 consecutively treated patients. All but one patient received rituximab for the treatment of non-Hodgkin's lymphoma. Eight episodes of grade 4 neutropenia were detected between 1 and 5 months after rituximab, when administered alone on five occasions, and on three occasions in combination with chemotherapy, where neutrophil counts had recovered prior to the development of neutropenia. In three episodes, the patients presented with sepsis. Development of neutropenia did not correlate with either the presence of detectable disease or the administration of further treatment. Neutropenia was associated with selective depletion of neutrophil precursors in all but one episode, where it was associated with generalized bone marrow hypoplasia. All episodes developed after a period of either normal or mildly depressed neutrophil counts following treatment with rituximab, and persisted for between several days and several months, before undergoing spontaneous recovery in four instances, and after administration of filgrastim in the remainder. Episodes of neutropenia were associated with disordered immune status manifested by lymphopenia and hypogammaglobulinaemia, raising the possibility that either disturbance of the balance of lymphocyte subsets or an immune dyscrasia induced by rituximab resulted in the development of this type of neutropenia. [source] FSH and ovarian response: spontaneous recovery of pituitary,ovarian activity during the pill-free period vs. exogenous recombinant FSH during high-dose combined oral contraceptivesCLINICAL ENDOCRINOLOGY, Issue 4 2002A. M. Van Heusden Summary ojbective Compare spontaneous recovery of pituitary,ovarian activity during the pill-free period following the correct use of low-dose oral contraceptives and subsequent ovarian function during the administration of exogenous recombinant FSH (recFSH) after switching to continued Lyndiol® (2·5 mg lynestrenol + 0·05 mg ethinyl-oestradiol) medication. design Prospective, randomized, group-comparative, single-centre study. Following the monitoring of the pill-free period (week 1) and subsequent treatment with Lyndiol® (for a total of 5 weeks), all subjects were randomly allocated to one of four groups receiving daily FSH injections for 1 week [75, 150, 225 IU recFSH or 150 IU purified urinary FSH (uFSH)] during the fourth week of Lyndiol® use. patients Thirty-six healthy volunteers aged 18,39 years, prestudy oral contraceptive use for at least 3 months, cycle length between 24 and 35 days. measurements Serum FSH, LH and oestradiol (E2) concentrations as well as transvaginal ultrasound assessment of the number and diameter of follicles > 2 mm were used to monitor pituitary ovarian function. results At the start of the pill-free period following the prestudy contraceptive medication, 67% of the women presented with LH and FSH levels < 1 IU/l and only one follicle > 10 mm was observed. Initial levels of LH and FSH correlated (P < 0·05) with the extent of pituitary,ovarian activity during the pill-free period. At the end of the pill-free period a follicle > 10 mm had emerged in one subject only. During the first 3 days of Lyndiol® use, seven women (19%) eventually showed at least one follicle > 10 mm. During combined exogenous FSH and Lyndiol® administration, LH levels remained completely suppressed (, 0·5 IU/l) in all women studied. FSH levels and number and size of follicles increased with increasing doses of exogenous FSH in a dose-dependent manner. E2 levels remained low in all groups (< 150 pmol/l). During the week following FSH administration, FSH levels and E2 levels decreased gradually while the number of follicles > 10 mm still increased. conclusions We have confirmed that dominant follicles > 10 mm are present at the end of the pill-free period and during the first days after resumption of pill intake. Once follicles > 10 mm arose at the end of the pill-free period, continued use of Lyndiol® did not reduce follicle diameters. One week of Lyndiol® reduces pituitary,ovarian activity to levels observed after 3 weeks of low-dose pills. FSH administration during Lyndiol® resulted in dose-dependent follicle growth despite extremely low LH levels. E2 secretion (56 ± 51 pmol/l) occurred to a limited and variable extent along with extremely low serum LH concentrations. Recovery of pituitary,ovarian activity at the end of the pill-free period is comparable to FSH levels and follicle dynamics following 7 days of 75,150 IU/l recFSH. [source] | |||||||||||||