SEARCH · Search PubMed

Results for “Retention”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,297 records · Page 72Linked to original sources

PubMed1990

The role of age-dependent behaviors in the retention of an approach-avoidance response in preweanling rats.

The role of age-dependent responses in infantile amnesia was examined. Ten- and 15-day old rats were trained in an approach-mother, avoid-shock paradigm and tested for retention immediately and after a 1-day delay. Ten-day-old rats were also tested after 6 days. Half of all the pups received a shock reactivation treatment before the delayed retention tests and half did not. In comparison to immediate retention, performance declined after 1 day but was reinstated by reactivation. A similar reactivation effect was found on 10-day-old pups tested after 6 days except that a different age-specific response was substituted for the original behavior. These effects were not found in untrained controls. These data show that learning may be expressed differently when acquisition and retention are measured at different developmental stages, a pattern that may be mistaken for infantile amnesia.

Aging↗

PubMed2003

Urodynamic evaluation of surgical outcome in patients with urinary retention due to central lumbar disc prolapse.

AIMS: To investigate whether acute urinary retention due to central lumbar disc prolapse is reversible after emergency spinal surgery. METHODS: Eight patients (two males, six females) with a mean age of 31.5 years (range, 18-42 years) with urinary retention due to lumbar disc prolapse were studied. An emergency surgery was performed within 48 hours (mean, 42 hours) after the onset of urinary retention. Urodynamic study was performed before and after the operation. RESULTS: All patients had acontractile detrusor without bladder sensation and four of seven patients had inactive external sphincter on electromyogram at presentation. Two patients were unable to void up to 1 and 5 months after surgery and were then lost for follow-up. The remaining six patients could void with straining or changing their voiding postures (bending forward), postoperatively. A follow-up urodynamic study was performed in all patients from 1 month to 6 years postoperatively. All patients demonstrated acontractile detrusor on cystometrogram. On external sphincter electromyogram, four patients had normal activities. The remaining four patients recovered electromyographic activities, but two of them had denervation motor unit potentials and two had low activities. CONCLUSIONS: Bladder function was irreversible after spinal surgery, whereas urethral function showed a better recovery in patients with acute urinary retention due to central lumbar disc prolapse. However, most of our patients could empty their bladder only by straining or changing their voiding postures postoperatively.

Adolescent↗

PubMed1995

Post-training unilateral vagal stimulation enhances retention performance in the rat.

Many peripherally administered substances which modulate memory do not freely enter the brain. Such compounds may act through peripheral receptors that send messages centrally through vagal afferents. To explore this hypothesis, rats were chronically implanted with cuff electrodes on the left cervical vagus nerve. Each animal was trained 48 h after surgery on a one-trial inhibitory-avoidance task with a 0.75-mA, 1.0-s footshock. Immediately following training, each animal received either no stimulation or vagal stimulation (0.5-ms biphasic pulses; 20 Hz, 30 s) at one of three intensities (0.2, 0.4, 0.8 mA; eight animals per group). Retention was tested 24 h later. Neither the 0.2-in or 0.8-mA groups (22.1-s; 53.7-s median latency) showed altered retention performances, whereas the 0.4-mA group showed significantly improved retention (881.0 s) compared to unstimulated controls (21.1 s; U = 6, p < .01). This inverted-U shaped function indicates that vagal activation during memory consolidation modulates retention for memory tasks.

Animals↗

PubMed1999

MK-801 improves retention in aged rats: implications for altered neural plasticity in age-related memory deficits.

Alterations in N-methyl-d-aspartate receptor (NMDAR)-dependent synaptic plasticity, characteristic of aged rodents, may contribute to impaired memory with advanced age. The purpose of the current research was to examine whether NMDARs contribute to rapid forgetting on a spatial memory task. Aged (22-24 months) and adult (3-6 months) male Fischer 344 rats received 18 training trials, over a period of 3 to 4 h, on the spatial version of the Morris water maze. Immediately after training, a standard free-swim probe trial was administered to assess the acquisition of spatial bias, which was determined by the percent of time spent in the goal quadrant and the number of platform crossings. Rats then received injections of the noncompetitive NMDAR antagonist, (+)-10, 11-dihydro-5methyl-5H-dibenzo(a,b)cycloheptene-5,10 imine (MK-801, 0. 05 mg/kg, i.p.), or a vehicle injection of equal volume. Approximately 24 h later, rats were administered a second free-swim probe trial to assess retention of spatial bias. All age/drug groups exhibited a spatial bias on the acquisition probe, with adults generally outperforming the aged rats. On the retention probe, this spatial bias continued to be shown by adult rats, regardless of treatment. For the aged group, in contrast, only MK-801-injected rats maintained a spatial bias on the retention probe, suggesting that NMDAR activity may be involved in rapid forgetting during aging. Because blockade of NMDARs also may impair new learning, which may, in turn, protect previously stored information from retroactive interference, rats in a second experiment received post-training injections of scopolamine (0.05 mg/kg), a compound known to inhibit learning. However, scopolamine did not enhance retention in the aged group, consistent with the hypothesis that MK-801 influenced memory in aged rats through its actions on NMDAR-dependent synaptic plasticity.

Aging↗

PubMed1999

Chronic administration of propranolol impairs inhibitory avoidance retention in mice.

Adrenergic systems are importantly involved in memory storage processes. As such, agents that alter adrenergic receptors, such as "beta-blockers," also alter memory storage. However, the anxiety literature cautions that beta-adrenergic receptor antagonists, such as propranolol, may have different behavioral effects with acute vs chronic dosing. The effects of chronic propranolol specifically on memory modulation are unknown. This study was designed to evaluate the effects of chronic propranolol on retention for an aversive task, in which there is endogenous adrenergic activation. Adult male ICR mice were given daily injections of one of four doses of propranolol (2, 4, 8, and 12 mg/kg) or 0.9% NaCl vehicle for 15 days prior to, and continuing during, behavioral tests of exploration and retention. Exploratory behavior, as an index of anxiety level, was measured in a conventional elevated plus-maze, whereas retention of an aversive experience was measured in a step-through inhibitory avoidance apparatus. Sensitivity to aversive footshock was also evaluated. Compared to controls, propranolol-treated mice showed a dose-dependent decrease in retention for the inhibitory avoidance task, but no effect on anxiety on the plus-maze or on footshock sensitivity. Taken together with results from previous studies, it is apparent that propranolol can have different behavioral effects when administered acutely vs chronically, and its chronic effects significantly impair memory storage processes. Since these drugs are typically used chronically, and often in older adults, they could contribute to functional memory impairments.

Adrenergic beta-Antagonists↗

PubMed2000

Time-dependent impairment of inhibitory avoidance retention in rats by posttraining infusion of a mitogen-activated protein kinase kinase inhibitor into cortical and limbic structures.

Mitogen-activated protein kinase (MAPK) is abundantly expressed in postmitotic neurons of the developed nervous system. MAPK is activated and required for induction of long-term potentiation (LTP) in the CA1 area of the hippocampus, which is blocked by the specific inhibitor of the MAPK kinase, PD 098059. Recently it was demonstrated that MAPK is activated in the hippocampus after training and is necessary for contextual fear conditioning learning. The present work tests the role of the MAPK cascade in step-down inhibitory avoidance (IA) retention. PD 098059 (50 microM) was bilaterally injected (0.5 microl/side) into the CA1 region of the dorsal hippocampus or entorhinal cortex at 0, 90, 180, or 360 min, or into the amygdala or parietal cortex at 0, 180, or 360 min after IA training in rats using a 0.4-mA foot shock. Retention testing was carried out 24 h after training. PD 098059 impaired retention when injected into the dorsal hippocampus at 180 min, but not 0, 90, and 360 min after training. When infused into the entorhinal cortex, PD 098059 was amnestic at 0 and 180 min, but not at 90 and 360 min after training. The MAPKK inhibitor also impairs IA retention when infused into the parietal cortex immediately after training, but not at 180 or 360 min. Infusions performed into amygdala were amnestic at 180 min, but not at 0 and 360 min after training. Our results suggest a time-dependent involvement of the MAPK cascade in the posttraining memory processing of IA; the time dependency is different in the hippocampus, amygdala, entorhinal cortex, or parietal cortex of rats.

Amygdala↗

PubMed2002

Inhibition of guanylate cyclase and protein kinase G impairs retention for the passive avoidance task in the day-old chick.

Nitric oxide (NO) is a highly labile chemical messenger which has previously been implicated in memory processes in a variety of learning paradigms and species. However, there is only limited evidence to suggest which enzymes are acted upon by NO during the formation of memory. The present study investigates the role of guanylate cyclase (GC) and protein kinase G (PKG) in a form of passive avoidance learning known to be dependent on nitric oxide activity. It was determined that in vivo pharmacological inhibition of GC using either 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one or 6-anilino-5,8-quinolinedione resulted in two transitory memory retention deficits centred around 40 and 120 min posttraining, respectively. In contrast, inhibition of PKG with N-[2-(methylamino)ehtyl]-5-isoquinoline-sulfornamide hydrochloride (H-8) resulted in a single temporary retention loss centered at 120 min posttraining. These temporary retention losses appear to be specific to memory since they were dose-dependent and could not be explained by nonspecific performance effects. Further, these results suggest that these agents inhibit memory retrieval rather than formation, since memory is subsequently available. The current findings indicate that guanylyl cyclase mediates two memory retrieval processes, the latter of which appears to be PKG-dependent. In contrast, since inhibition of NO results in a permanent retention loss, it is suggested that NO is required for memory formation through GC-independent processes.

Aminoquinolines↗

PubMed2002

Long-term consolidation and retention of learning-induced tuning plasticity in the auditory cortex of the guinea pig.

The major goal of this study was to determine whether classical conditioning produces long-term neural consolidation of frequency tuning plasticity in the auditory cortex. Local field potentials (LFPs) were obtained from chronically implanted adult male Hartley guinea pigs that were divided into conditioning (n = 4) and sensitization control (n = 3) groups. Tuning functions were determined in awake subjects for average LFPs (approximately 0.4 to 36.0 kHz, -20 to 80 dB) immediately before training as well as 1 h and 1, 3, 7, and 10 days after training; sensitization subjects did not have a 10-day retention test. Conditioning consisted of a single session of 30 to 45 trials of a 6-s tone (CS, 70 dB) that was not the best frequency (BF, peak of a tuning curve), followed by a brief leg shock (US) at CS offset. Sensitization control animals received the same density of CS and US presentations unpaired. Heart rate recordings showed that the conditioning group developed conditioned bradycardia, whereas the sensitization control group did not. Local field potentials in the conditioning group, but not in the sensitization group, developed tuning plasticity. The ratio of responses to the CS frequency versus the BF were increased 1 h after training, and this increase was retained for the 10-day period of the study. Both tuning plasticity and retention were observed across stimulus levels (10-80 dB). Most noteworthy, tuning plasticity exhibited consolidation (i.e., developed greater CS-specific effects across retention periods), attaining asymptote at 3 days. The findings indicate that LFPs in the auditory cortex have three cardinal features of behavioral memory: associative tuning plasticity, long-term retention, and long-term consolidation. Potential cellular and subcellular mechanisms of LFP tuning plasticity and long-term consolidation are discussed.

Animals↗

PubMed1975

Effects of serial lesions of somatosensory cortex and further neodecortication on tactile retention in rats.

Four groups of rats with bilateral lesions of somatosensory cortex and one of animals sustaining only sham operations were tested for retention of a difficult tactile discrimination. Two of the lesion groups had serial ablations, in one case with interoperative testing, and two had one-stage lesions. Bilateral ablations of somatosensory cortex severely retarded retention in all lesion groups relative to the control group and serial and one-stage groups did not differ from each other. The sham operated rats then experienced lesions of cortex anterior and posterior to the somatosensory areas. These lesions only marginally affected retention. Somatosensory cortex then was ablated and severe performance decrements were seen. Removal of additional neocortex in animals that previously had relearned the discrimination after somatosensory cortex lesions also resulted in very poor retention. These data demonstrate the importance of the somatosensory cortex in mediating tactile discriminations and suggest that non-somatosensory cortex may play a role in recovery after somatosensory cortical lesions.

Animals↗

PubMed1977

Impairment of retention of avoidance responses in rats by posttraining diethyldithiocarbamate.

Diethyldithiocarbamate (680 mg/kg), administered immediately after training, impaired rats' retention, 6 days later, of a one-way active avoidance task and a discriminated active avoidance task. In the discrimination task a lower dose (340 mg/kg) also impaired retention. Delayed posttraining injections did not affect retention in either task. The findings indicate that DDC can have similar effects on retention of tasks requiring quite different behavioral responses.

Animals↗

PubMed1998

Urinary retention after operations for benign anorectal diseases.

PURPOSE: This study was undertaken to determine the incidence and risk factors for urinary retention after operations for benign anorectal diseases. METHODS: We reviewed 1,026 consecutive operations for benign anorectal diseases from 1989 to 1994. Risk factor analysis was done for patients undergoing hemorrhoidectomy (Group I) and other procedures (Group II) using logistic regression analysis. RESULTS: The number of procedures and urinary retention rate was as follows: 344 (34 percent) hemorrhoidectomies, 159 (2 percent) fistulotomies, 95 (5 percent) incision/drainage, 247 (4 percent) lateral internal sphincterotomy, 181 (17 percent) combinations of the above four procedures, and overall 1,026 (16 percent). In Group I, four-quadrant excision (odds ratio, 3.3; P = 0.0004), three quadrant excision (odds ratio, 2.4; P = 0.003), morphine equivalents >33 (odds ratio, 1.8; P = 0.01), and male gender (odds ratio, 1.7; P = 0.02) were independent risk factors. In Group II, more than one operation (odds ratio, 3.0; P = 0.004), older age (odds ratio, 3.1; P = 0.005), intraoperative fluids (odds ratio, 2.6; P = 0.03), and postoperative fluids (odds ratio, 2.7; P = 0.02) were independent risk factors. Urinary obstructive symptoms for both groups and perioperative fluids for Group I were NOT independent risk factors. Hospital stay was prolonged significantly in patients with urinary retention (P = 0.0001). CONCLUSIONS: Urinary retention is a common postoperative complication that increases hospital stay. It is most common after hemorrhoidectomy. Disease severity (quadrants excised and analgesia requirement for Group I and number of operations for Group II) is an important risk factor for both groups studied. Older age in Group I and perioperative fluid in Group II may be important risk factors.

Abscess↗

PubMed1994

Ambulatory surgical hemorrhoidectomy--a solution to postoperative urinary retention?

PURPOSE: The most frequent complication of surgical hemorrhoidectomy is urinary retention. This study evaluates the incidence of urinary retention in a series of patients undergoing surgical hemorrhoidectomy in an ambulatory setting. METHODS: The records of all patients undergoing anorectal surgical operative procedures during the calendar year 1990 were reviewed, with particular emphasis on urinary retention and other postoperative complications. RESULTS: Of 201 patients undergoing full surgical hemorrhoidectomy by Colon and Rectal Clinic, 91 percent had operations performed on an ambulatory basis (discharge less than four hours following surgery). Of these 190 patients, only 1 (0.53 percent) required urinary catheterization during the postoperative period. CONCLUSIONS: The ambulatory setting, when combined with careful patient education and perioperative fluid restriction, allows surgical hemorrhoidectomy to be performed with a very low incidence of urinary retention to the benefit of both patient and surgeon.

Adult↗

PubMed2001

Isolated urinary retention in young women, or Fowler's syndrome.

A group of women with otherwise unexplained urinary retention occurring as an isolated phenomenon have been shown to have abnormal urethral sphincters, as assessed by electromyography, transvaginal ultrasonographic volume and pressure profile. A questionnaire survey of a number of women diagnosed with the disorder showed that there was a common natural history, and from the results it was possible to build up a profile of the "typical" patient. She is likely to be between 20 and 35 years old and also to have polycystic ovaries. Before the onset of retention she is likely to have had a relatively mild voiding dysfunction, such as infrequent voiding or an intermittent stream. Commonly her first retention episode will follow a triggering event such as an operation or childbirth. The retention is unlikely to resolve but is not associated with the development of other disorders. Neuromodulation of the sacral nerves is the only intervention that has been demonstrated to restore voiding.

Adult↗

PubMed2003

Incidence and treatment of urinary retention postpartum.

The aim of this clinical study was to examine the incidence of postpartum urinary retention, to investigate the relationship between different obstetric parameters, and to find out whether our proposed treatment program fulfilled our needs. The incidence of urinary retention postpartum was 0.7%. The incidence of instrumental delivery, sphincter rupture, and larger lacerations of the perineum was significantly increased in the group with urinary retention. Our program for detecting and treating patients with postpartum urinary retention seemed to work efficiently.

Adult↗

PubMedDate not supplied

Prospective 3D ultrasonographic evaluation of immediate postpartum urine retention volume in 100 women who delivered vaginally.

Our objective was to determine the reproducibility and validity of urine retention volumes measured by 3D ultrasonography (3D-US) 2 h postpartum. This was a longitudinal prospective study of 100 women who delivered vaginally. Each woman underwent five successive urine retention measurements with the Bladder Scan 2 h after vaginal delivery, followed by transurethral catheterization to determine the real volume. The reproducibility of only the last four scan values was analyzed with an intraclass correlation coefficient, and that of determinations 4 and 5 with a Bland-Altman plot. The validity of the device was similarly evaluated using the mean four-scan and real values. Pearson's correlation coefficient was calculated and a least-trimmed squares robust linear-regression model was used. All tests were two-sided with a 5% alpha risk. Results showed that 3D-US measurements were highly reproducible, with an intraclass correlation coefficient of 0.974 (95% CI:0.964-0.981). 3D-US also accurately estimated the real urine volume (intraclass correlation coefficient 0.924; 95% CI:0.888-0.949), but tended to underestimate by about 6.8%. The between-technique Pearson correlation coefficient was 0.94 (P < 0.0001) and the regression analysis gave an R2 of 0.914. Urine retention volumes exceeded 500 ml in 55 women, and 11 in 7. We concluded that 3D-US was reliably able to measure postpartum urine retention volume.

Adult↗

PubMed1999

The retention deficit induced by (RS)-alpha-methyl-4-carboxyphenylglycine in a lever-press learning task is blocked by selective agonists of either group I or group II metabotropic glutamate receptors.

The effects of immediate post-training administration of drugs interacting with group I and/or group II glutamate metabotropic receptors (mGluRs) were determined on the retention performance of a partially acquired lever-press learning task in mice. The antagonist (RS)-alpha-methyl-4-carboxyphenylglycine (MCPG) dose-dependently (0. 1-100 nmol/mouse, i.c.v.) impairs the retention performance evaluated 24 h post-training. The retention deficit induced by 100 nmol MCPG is related to the selective suppression of a time-dependent spontaneous improvement of performance between the two sessions. This phenomenon appears progressively within 24 h post-training in control mice and is thought to reflect post-training processing of memory traces. The coadministration of either (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (ACPD), the group I mGluR agonist (R,S)3,5-dihydroxyphenylglycine (DHPG), or the group II mGluR agonist LY354740, completely blocked MCPG-induced deficits at a dose of 0.1 nmol for each agonist. These results suggest that selective activation of either group I or group II mGluRs is able to prevent the memory retention deficits induced by MCPG.

Animals↗

PubMed2003

The role of the carbachol test and concomitant diseases in patients with nonobstructive urinary retention undergoing sacral neuromodulation.

The aim of this study was to evaluate the percutaneous nerve evaluation (PNE) test success in patients with nonobstructive urinary retention. A total of 24 PNE tests were performed in patients with nonobstructive urinary retention and in 18 patients, a carbachol test was performed during urodynamics. The diagnosis relating to the acontractile detrusor was also assessed and compared to the outcome of the PNE test. The PNE test was successful in eight of 24 patients (33.3%) with the the highest success rate being observed in patients after hysterectomy (80%). It was successful in five of 12 patients with negative carbachol tests and in three of six patients with positive carbachol tests. We conclude that sacral neuromodulation is an effective treatment option in patients with nonobstructive urinary retention. PNE tests should be performed in all patients with therapy resistant nonobstructive urinary retention, because predictive factors do not exist.

Adult↗

PubMed2006

Acute urinary retention due to benign inflammatory nervous diseases.

Both neurologists and urologists might encounter patients with acute urinary retention due to benign inflammatory nervous diseases. Based on the mechanism of urinary retention, these disorders can be divided into two subgroups: disorders of the peripheral nervous system (e.g., sacral herpes) or the central nervous system (e.g., meningitis-retention syndrome [MRS]). Laboratory abnormalities include increased herpes virus titers in sacral herpes, and increased myelin basic protein in the cerebrospinal fluid (CSF) in some cases with MRS. Urodynamic abnormality in both conditions is detrusor areflexia; the putative mechanism of it is direct involvement of the pelvic nerves in sacral herpes; and acute spinal shock in MRS. There are few cases with CSF abnormality alone. Although these cases have a benign course, management of the acute urinary retention is necessary to avoid bladder injury due to overdistension. Clinical features of sacral herpes or MRS differ markedly from those of the original "Elsberg syndrome" cases.

Acute Disease↗