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PubMed1997

The influence of smoking on reward responsiveness and cognitive functions: a natural experiment.

AIMS: To investigate the effects of (a) nicotine abstinence and (b) cigarette smoking after abstinence, on reward responsiveness and cognitive functions which are putatively dependent on activity in the dopaminergic system implicated in smoking. DESIGN: During Ramadhan, Muslim smokers elected to abstain from smoking either for the whole month (RAMQUIT) or during daylight hours (DAYQUIT). These groups, and non-smokers (NOSMOKE), were assessed on two occasions 6 hours apart (TEST1 and TEST2). DAYQUIT participants had abstained for 6 hours at TEST1 and smoked a single cigarette immediately prior to TEST2. RAMQUIT participants had abstained for at least 10 days prior to TEST1 and remained abstinent at TEST2. NOSMOKE and RAMQUIT participants are a small snack prior to TEST2 to control for non-specific consummatory effects. SETTING: TEST1 was conducted at the mosque and TEST2 in participants' homes. PARTICIPANTS: All were male; mean age was 26.7 years. Modal cigarette consumption prior to Ramadhan by both the 13 DAYQUIT and the 11 RAMQUIT smokers was 21-30 per day. DAYQUIT subjects rated themselves as more dependent. MEASUREMENTS: The Card Arranging Reward Responsivity Objective Test (CARROT), testing behavioural responsiveness to small financial incentive; digit span, measuring attention; verbal fluency, indexing frontal lobe function; and the two-choice guessing test (2CGT; at TEST1 only), measuring response stereotypy. FINDINGS: At TEST1, compared with non-smokers, both smoking groups showed greater stereotypy (2CG) and lower reward responsiveness (CARROT). DAYQUIT participants improved on all measures after smoking a single cigarette. No marked changes were seen in the other groups. CONCLUSION: These data suggest that (i) abstaining smokers have impaired dopaminergic function and (ii) nicotine consumption may boost their dopaminergic activity.

Adult↗
PubMed2005

Vardenafil improved patient satisfaction with erectile hardness, orgasmic function and sexual experience in men with erectile dysfunction following nerve sparing radical prostatectomy.

PURPOSE: Nerve sparing radical retropubic prostatectomy (NS-RRP) results in erectile dysfunction in a significant number of patients. Vardenafil, a potent and selective phosphodiesterase type 5 inhibitor, is generally safe. It improves International Index of Erectile Function erectile function domain scores, and penetration and erection maintenance success rates in patients who have undergone NS-RRP. We report additional parameters important to patient perceptions regarding erection quality and satisfaction with sexual experience following NS-RRP. MATERIALS AND METHODS: A total of 440 men at 58 centers throughout the United States and Canada participated in this randomized, placebo controlled, double-blind trial with 3 phases, namely baseline (4-week untreated period), treatment (12 weeks) and followup (7 days). Participants received placebo (145), 10 mg vardenafil (146) or 20 mg vardenafil (149) at home on demand but no more than once per calendar day. Efficacy and satisfaction with erection quality and sexual experience were determined during the trial. RESULTS: The 10 and 20 mg vardenafil doses were significantly superior to placebo for the International Index of Erectile Function domains for intercourse satisfaction, orgasmic function and overall satisfaction with sexual experience (vs placebo p <0.0009). Significant improvement in the satisfaction rate with erection hardness were demonstrated for each vardenafil dose compared with placebo (p <0.0001). Vardenafil was generally well tolerated. Common adverse events were headache, vasodilatation and rhinitis. CONCLUSIONS: In this difficult to treat population of men with erectile dysfunction subsequent to NS-RRP on demand treatment with vardenafil during a 3-month period significantly improved key aspects of the sexual experience important to patient quality of life.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed1989

Negative hallucinations, other irretrievable experiences and two functions of consciousness.

After providing a psychodynamic exploration of negative hallucinations in four clinical cases, the focus of this paper was broadened in an attempt to understand the mechanism of negative hallucination. To this end, after defining the term 'irretrievable experiences', two other examples--preconscious perceptions and infantile amnesia, both analogues to negative hallucination--were examined. A discussion followed concerning two types of 'consciousness': 'consciousness' as a synonym for 'awareness' and 'consciousness' as a distinct psychological state. Next, the role of different functions of each sort of consciousness in the processes of conferring, fixing and retrieving mental contents within particular categories of experience was taken up. Finally, integrating developmental aspects of these same functions, explanations were offered regarding the mechanisms involved in preconscious perception, infantile amnesia and negative hallucinations.

Adult↗
PubMed2002

Neural substrates of memory, affective functions, and conscious experience.

This review presents an account of the areas and circuits of the brain that are thought to be involved in such cognitive functions as memory, affect and consciousness. Considerable progress has been made in the past two decades in the identification of the cerebral areas and in our understanding of the brain mechanisms involved in these functions, thanks in large parts to a number of imaging observations (PET and fMRI), together with many clinical neurological and experimental studies. Thus, there is now convincing evidence that these high level functions are represented in a complex organization of interconnected cortical and subcortical areas that operate as spatially distributed systems, specialized for the different cognitive activities. Despite the progress that has been made, it is still not known how genetic and environmental factors interact during early development and throughout life to create the necessary conditions out of which these cognitive capacities emerge, nor is it evident to what extent they are shaped by adaptive changes in synaptic organization and other forms of neuronal plasticity.

Brain Mapping↗
PubMed2005

[Auditory-evoked brainstem response in a schwannoma of the VIIIth cranial nerve: an anatomophysiological and functional correlation. Our experience].

INTRODUCTION: Schwannomas are tumors charasteristically originated from the nerve sheath. They expande eccentrically from the nerve promoting a disturbance in the neural function either due to vascular compresion or to the effect of the tumor itself on the nerve, disturbance that can be evidenced with the Auditory-evoked Brainstem Response (ABR), fact that constituted the base for their diagnosis in the past. The new radiological techniques developed over the last decades have made possible an earlier diagnosis, and therefore changed their prognosis in terms of nerve function. Diagnosis is more certain today with these techniques so it could seem that ABR may not have any longer a role in the management of this condition. OBJECTIVE: To describe the most frequent ABR patterns in those patients suffering from acoustic schwannoma related to the size of the tumour and the remanent audition thresholds, and to determine the value of this test in our practice. MATERIAL AND METHODS: We describe the ABR features found in our series of 72 patients. Whose diagnosis was done between 1997 and 2003 in relation to the size of the tumour and the residual auditory function. RESULTS AND CONCLUSIONS: ABR has a good sensibility for detection of acoustic schwannoma. This sensibility decreases in small-sized tumours, specially in intracanalicular ones. ABR patterns do not relate to the size of the tumour but they do to the auditory function. The authors defend ABR to be a very valuable test due to the information and accesibility they provide.

Cranial Nerve Neoplasms↗
PubMed1980

Total anomalous pulmonary venous connection in infancy. Ten years' experience including studies of postoperative ventricular function.

The surgical experience with total anomalous pulmonary venous connection (TAPVC) at the Venderbilt Hospital between the years 1969 and 1979 was reviewed. Twenty-five patients with TAPVC were studied. All but one patient presented at less than 1 year of age, and 11 patients were operated upon in the first 2 weeks of life. Operative mortality rate was 20% (5/25). Four of the five deaths were in critically ill neonates requiring preoperative ventilatory support. All operative deaths were in patients with pulmonary venous obstruction. All operative survivors have been followed for a mean 4.5 years (6 months to 10 years). There have been no late deaths or cases of symptomatic pulmonary venous obstruction. All children have had normal growth patterns. Ten patients have been recatheterized. Pulmonary artery systolic pressure, which was markedly elevated prior to operation, fell to normal levels after operation. Ventricular function has been evaluated by quantitative angiocardiography in nine patients before and after operation. Left ventricular size and function were markedly depressed preoperatively and rose to normal levels in postoperative survivors. Left atrial maximal volume was found to be 94% of normal values. These data support the contention that preoperative pulmonary venous obstruction is the single risk factor predicting higher risk of operative death. The presence of severe depression of left ventricular size and function preoperatively does not predict a higher operative risk, and postoperative survivors can expect normal ventricular function.

Angiocardiography↗
PubMed2001

Characteristics of maltreatment experience and academic functioning among maltreated children.

This article examined the impact of maltreatment characteristics on academic functioning in a sample of school-age maltreated children. Results revealed several differences among three types of maltreatment subgroups (physical abuse, neglect, and sexual abuse) on characteristics of maltreatment experience. Few maltreatment characteristics were significantly related to measures of academic functioning, but the findings suggest that the effects of maltreatment characteristics should be examined separately for different types of maltreatment.

Age Factors↗
PubMed1996

Supracricoid laryngectomy with cricohyoidopexy (CHP) in the treatment of laryngeal cancer: a functional and oncologic experience.

Subtotal laryngectomy with cricohyoidopexy (CHP) results in a satisfactory cure rate in selected T1b, T2, and T3 supraglottic and glottic cancers. The clinical, oncologic, and functional results of this type of surgery have led to an ever-increasing number of patients undergoing this procedure. This study involved 70 patients operated on from 1984 to 1993 using this surgical procedure. This report also discusses the clinical (cTNM) and pathologic (pTNM) classifications of CHP cases. Fifty-two of these patients were evaluated after a follow-up of more than 3 years. Lymph node treatment protocol comprised 51 functional ipsilateral neck dissections (FNDs), 9 bilateral FNDs, 1 radical ipsilateral dissection, and 1 radical ipsilateral and contralateral FND. There were 6 recurrences (5 local, 1 neck); after CHP physiologic deglutition was recovered in most of the patients (95.5%), and all but 6 (92%) were decannulated. Results were excellent after phoniatric rehabilitation. This surgical procedure may be indicated for selected laryngeal cancers and allows for the preservation of laryngeal functions even when the neoplastic lesions are advanced. However, care must be taken when evaluating the infiltration of the paraglottic space, as that infiltration represents the main cause of failure in this type of surgery.

Adult↗
PubMed2006

Preliminary evidence of asymmetry in uncomfortable loudness levels after unilateral hearing aid experience: evidence of functional plasticity in the adult auditory system.

The aim of the study was to compare uncomfortable loudness levels (ULLs) in a group of adults before and after unilateral hearing aid experience. Twelve participants presented with a symmetrical hearing loss consistent with natural ageing. Pure tones were presented to each ear separately, commencing at 60 dB HL and increased in 5-dB step sizes until ULL was reached. The post-fitting ULLs were typically measured three years after fitting. Hearing thresholds were symmetrical and remained unchanged after fitting. Mean ULL values were symmetrical before fitting. The mean ULL values increased (i.e. greater tolerance) in both ears after fitting; however, the increase was greatest in the fitted ear: 14.5 and 7 dB at 2000-4000 Hz in the fitted and not-fitted ear, respectively. A separate two-factor repeated ANOVA (ear and frequency) was performed on the pre and post-fitting ULL data. There was no statistically significant difference for ear (p > 0.05) when comparing the pre-fitting ULLs. However, there was a statistically significant difference for ear (p < 0.01) when comparing post-fitting ULLs. The underlying mechanism for the asymmetry is unknown but it is consistent with learning induced reorganization within the auditory system.

Acoustic Stimulation↗
PubMed2006

Diversity in in-group bias: structural factors, situational features, and social functions.

Four experiments addressed the different forms and functions of in-group bias in different contexts. The authors proposed 2 functions: an identity-expressive function and an instrumental function (or promotion of positive social change). The authors manipulated status differentials, the stability of these differences, and the communication context (intra- vs. intergroup) and measured in-group bias and both functions. As predicted, identity expression via in-group bias on symbolic measures was most important for stable, high-status groups. By contrast, material in-group bias for instrumental motives was most prevalent in unstable, low-status groups but only when communicating with in-group members. This latter effect illustrates the strategic adaptation of group behavior to audience (i.e., displaying in-group bias may provoke the out-group and be counterproductive in instrumental terms). Stable, low-status groups displayed more extreme forms of in-group bias for instrumental reasons regardless of communication context (i.e., they had nothing to lose). Results are discussed in terms of a contextual-functional approach to in-group bias.

Adult↗
PubMed1995

Impact of acute pulmonary rejection on cardiac function.

BACKGROUND: Experiments were designed to define cardiac function in dogs with single lung allografts during acute rejection of the allografted lung. METHODS AND RESULTS: Left lungs were either autotransplanted (n = 4) or allotransplanted (n = 8) in adult male mongrel dogs. All allotransplanted animals were maintained on triple-drug immunosuppression (cyclosporine, azathioprine, and steroids) for 5 days after the operation. In 4 allotransplanted animals, treatment was discontinued, allowing the animals to reject (usually after a further 3 days; rejecting group); 4 other allotransplanted animals were maintained on immunosuppression for an additional 3 days (immunosuppressed group). Another group of dogs were not operated on but were maintained on the same immunosuppression as the rejecting group (controls). All experimental animals underwent fast computed tomographic scanning with measurement of left ventricular pressure and calculation of ventricular chamber volumes, cross-sectional areas of coronary arteries, myocardial perfusion, and intramyocardial blood volume. Neither cardiac output, left ventricular mass, left ventricular pressure, nor myocardial oxygen consumption was altered during acute rejection of lung allografts. However, left ventricular contractility (systolic elastance, Emax) and ejection fraction were depressed to approximately one half (P < .05) in acutely rejecting animals compared with other groups. The cross-sectional area of the coronary arteries was less in autotransplanted and allotransplanted treated animals than in animals that were not operated on. Cross-sectional area of the coronary arteries was decreased by an additional 30% in the rejecting group (P < .05). CONCLUSIONS: The results of this study indicate that acute rejection of a single lung allograft decreases cardiac performance and reduces diameter of coronary arteries in the recipient. Alterations of circulating humoral factors and activated leukocytes may contribute to these changes.

Animals↗
PubMed2002

On the role of covarying functions in stimulus class formation and transfer of function.

This experiment investigated whether directly trained covarying functions are necessary for stimulus class formation and transfer of function in humans. Initial class training was designed to establish two respondent-based stimulus classes by pairing two visual stimuli with shock and two other visual stimuli with no shock. Next, two operant discrimination functions were trained to one stimulus of each putative class. The no-shock group received the same training and testing in all phases, except no stimuli were ever paired with shock. The data indicated that skin conductance response conditioning did not occur for the shock groups or for the no-shock group. Tests showed transfer of the established discriminative functions, however, only for the shock groups, indicating the formation of two stimulus classes only for those participants who received respondent class training. The results suggest that transfer of function does not depend on first covarying the stimulus class functions.

Adult↗
PubMed1993

Cryopreserved venous allografts: effects of immunosuppression and antiplatelet therapy on patency and function.

PURPOSE: Experiments were designed to determine the function of the endothelium and smooth muscle in cryopreserved and fresh canine saphenous vein allografts. METHODS: Reversed interposition saphenous vein grafts were implanted into the femoral arteries of two groups of dogs: group 1 received one freshly harvested saphenous vein allograft and group 2 received one cryopreserved saphenous vein allograft. The contralateral femoral artery in each group was replaced with a freshly harvested autogenous saphenous vein. Animals received oral cyclosporine alone (n = 3) or in combination with aspirin (325 mg/day; n = 20). RESULTS: Four weeks after surgery, none of the cryopreserved grafts was patent in the group treated with cyclosporine alone. All grafts were patent in animals treated with cyclosporine and aspirin. At 4 weeks, blood flow through cryopreserved allografts was significantly greater than in freshly harvested allografts. Platelet deposition was comparable in cryopreserved and freshly harvested allografts immediately after implantation and at 4 weeks. Rings cut from the grafts were suspended for the measurement of isometric force in organ chambers. alpha-Adrenergic agonists and endothelin caused concentration-dependent contractions in fresh autografts and allografts. After submaximal contraction with prostaglandin F2 alpha in these same grafts, calcium ionophore and thrombin caused relaxations in rings with endothelium, and nitric oxide caused relaxations in rings without endothelium. Cryopreserved allografts did not respond to any of the agonists tested. Histologic examination of the tissue indicated smooth muscle cells in cryopreserved grafts; evidence of rejection was observed in all allografts. CONCLUSION: These results indicate that cryopreserved allografts remain patent with antiplatelet and immunosuppressive therapy in spite of loss of functional smooth muscle.

Animals↗
PubMedDate not supplied

Functional CT imaging of the acute hyperemic response to radiation therapy of the prostate gland: early experience.

PURPOSE: Functional CT can measure perfusion and permeability. We hypothesized that acute changes could be measured in these indexes following radiation therapy (RT) to the prostate gland. METHOD: Twenty-two patients with prostatic cancer were studied before and 1-2 and 6-12 weeks after RT. A single section through the prostate was repeatedly scanned after contrast medium bolus injection. Contrast agent clearance per unit volume (alpha/V) and fractional vascular volume (fvv) were calculated using Patlak graphical analysis. Perfusion was calculated as the ratio between maximal rate of tissue enhancement and peak arterial enhancement. RESULTS: Significant increases in all indexes occurred after RT. Mean perfusion rose from 0.122 to 0.263 ml/min/ml at 1-2 weeks, mean alpha/V increased from 0.0012 to 0.0016 ml/min/ml at 1-2 weeks, and mean fvv increased from 13.7 to 21% at 1-2 weeks. All three indexes remained elevated at 6-12 weeks after the start of RT. CONCLUSION: Functional CT demonstrated an acute hyperemic response following RT to the prostate gland.

Acute Disease↗
PubMed1982

Brain stimulation in the study of neuronal functions for conscious sensory experiences.

Some features of cerebral neuronal functions that are uniquely related to generation of conscious sensory responses, have been discovered. Included are two temporal factors: (1) Substantial delays, of up to about 0.5 sec, before achieving cerebral "neuronal adequacy" appear to be required for eliciting a sensory experience. This includes the demonstration that a cortical stimulus (C) can retroactively modify a skin (S)-induced sensation even when C stimulus begins up to 500 msec after S stimulus. (2) However, there appears to be a subjective referral of the experience back to the time of the cortical primary evoked response to S; subjectively the skin sensation would thus appear to have no delay. Stimuli that are inadequate for eliciting conscious sensory experience can nevertheless evoke considerable neuronal activity, including that represented in direct cortical responses or in primary (early) components of evoked potentials. Virtually all the qualities of somatic sensation (except pain) can be elicited by stimuli at post-central gyrus, when intensities of suitable trains of pulses are kept down to liminal levels. Some additional implications, for the manner in which mental and neural events are related, are discussed.

Arousal↗
PubMed1985

[Rehabilitation programs for patients with cochlear implants as a function of acquired experience in logopedics for deaf children].

Rehabilitation of patients after cochlear implant surgery should be planified along the same basic principles as those that have been envolved for the adaptation of patients to a classical hearing aid or acoustic prosthesis. When this is adapted to a patient with a sensorineural hearing loss, the quality of hearing differs from that of normal hearing because the pathological inner ear introduces distorsions. The patient therefore has to be trained to equate the new auditory sensations with those he had previously, which is basically the same situation as with a cochlear implant. Some profoundly or totally deaf patients are fitted with vibro-tactile aids and they also have to be trained to make use of these new sensations in a meaningful way for an aid to speech understanding. For the above reasons the term "cochlear prosthesis" is considered particularly adequate. It also has the advantage of playing down the surgical aspect of this new technique, often overemphasized by the media and creating exaggerated emotional involvement of the patients. If the above facts are recognized, one should entrust the rehabilitation of patients fitted with cochlear prostheses to logopeds (speech therapists) well trained in the habilitation and prosthetic adaptation of profoundly deaf children. Only they have the expertise necessary to devise and apply a program founded upon experience. This will help avoid the pitfalls into which several surgically directed cochlear implant teams are currently falling. One of these is to design a training program in function of the tests meant to measure the patients' new capacities.(ABSTRACT TRUNCATED AT 250 WORDS)

Child↗
PubMed2001

[Functional constipation syndrome: experience in the use of sour milk products and biologically active food supplements in the complex treatment of patients].

Sour milk product "Bifeedock" and biologically-active food additives of "Litovite" and "Pektsecom" type are used in the overall treatment of functional constipation and accompanying colon disbacteriosis of I and II degree. They help to improve the clinical symptomatics and the functional state of the gastrointestinal tract. According to the data analysis, the elimination of the colon stasis results in the improved microbiocenosis expressed in the suppression of growth of conditionally pathogenic microflora. It also stimulates the growth of the symbiotic elements of microbiota (bifidobacteria, lactobacteria and the intestinal E. coli).

Adult↗