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PubMed1988

Flow reversal in the normal carotid bifurcation: color Doppler flow imaging analysis.

One hundred carotid bifurcations in young asymptomatic volunteers were examined with color Doppler flow imaging in an attempt to determine the frequency, configuration, magnitude, and duration of flow reversal. Areas of flow reversal were identified in all but one bifurcation. Just proximal to the bifurcation, flow reversal was typically located peripherally, opposite the origin of the external carotid artery. Distal to the bifurcation, flow reversal in the internal carotid artery typically assumed a linear configuration in the center of the vessel, extending from the superficial to the deep wall. Variations of these patterns were common. On the average, flow reversal occupied 33% of the lumen of the carotid bulb and extended for a distance of 14 mm. The average duration of flow reversal was 22% of the total cardiac cycle, with reversal typically occurring at peak systole and being replaced by static blood during diastole. These findings indicate that flow reversal in the carotid bifurcation is a normal phenomenon with a variable configuration, magnitude, and duration.

Adult↗
PubMed2005

Encoding changes in orbitofrontal cortex in reversal-impaired aged rats.

Previous work in rats and primates has shown that normal aging can be associated with a decline in cognitive flexibility mediated by prefrontal circuits. For example, aged rats are impaired in rapid reversal learning, which in young rats depends critically on the orbitofrontal cortex. To assess whether aging-related reversal impairments reflect orbitofrontal dysfunction, we identified aged rats with reversal learning deficits and then recorded single units as these rats, along with unimpaired aged cohorts and young control rats, learned and reversed a series of odor discrimination problems. We found that the flexibility of neural correlates in orbitofrontal cortex was markedly diminished in aged rats characterized as reversal-impaired in initial training. In particular, although many cue-selective neurons in young and aged-unimpaired rats reversed odor preference when the odor-outcome associations were reversed, cue-selective neurons in reversal-impaired aged rats did not. In addition, outcome-expectant neurons in aged-impaired rats failed to become active during cue sampling after learning. These altered features of neural encoding could provide a basis for cognitive inflexibility associated with normal aging.

Action Potentials↗
PubMed1999

Reversible and irreversible airflow obstruction as predictor of overall mortality in asthma and chronic obstructive pulmonary disease.

The importance of reversible airflow obstruction to the prognosis of asthma and chronic obstructive pulmonary disease (COPD) is not clear. We tested the hypothesis that reversibility to corticosteroid and bronchodilator is not an independent predictor of prognosis, but merely reflects a component of the maximal attainable lung function, which is the best spirometric predictor of survival. During a 6-yr period (1983-1988), 1,586 subjects with asthma or COPD underwent standardized bronchodilator and corticosteroid reversibility tests at a chest clinic in Copenhagen. The vital status was obtained by September 1997. The relationship between mortality and age, gender, smoking, FEV1, and reversibilities was examined by Cox proportional hazards analyses. Of 1,586 subjects, 850 had died before September 1997. Age, smoking, and FEV1 were significant predictors of mortality. After controlling for baseline FEV1, bronchodilator and corticosteroid reversibility were significantly associated with better survival. However, after controlling for best FEV1 all reversibilities became nonsignificant and nonpredictive. The combined use of corticosteroid and bronchodilator reversibility in survival analyses is a novel approach, and we have shown that both contribute to survival prediction to the extent that they modify FEV1. However, reversibility per se does not influence survival in subjects with moderate to severe asthma or COPD.

Asthma↗
PubMed1997

Reversed neurovegetative symptoms of depression: a community study of Ontario.

OBJECTIVE: Most research on depression with reversed neurovegetative features (hypersomnia, hyperphagia, and weight gain) has been based on site-specific clinic-based samples. The goal of this study was to delineate the epidemiology of reversed symptoms in a large community sample and to use other symptom patterns for comparison. METHOD: Interviewers assessed 8,116 subjects across Ontario, aged 15-64 years, by using the World Health Organization Composite International Diagnostic Interview. Individuals who met the DSM-III-R criteria for major depression, current or lifetime, were classified into four groups on the basis of lifetime neurovegetative symptoms: episodes of typical symptoms only, episodes of reversed symptoms only, neither type, or both types (fluctuating-symptom group). The groups were compared on demographic characteristics, comorbidity, disability, and health care utilization. RESULTS: Of the 653 individuals with lifetime major depression, 11.3% had episodes of reversed symptoms only, and another 5.8% were classified as fluctuating. Most of the differences among the four groups were due to the unique characteristics of the groups with neither type of episode or a fluctuating pattern; individuals who had experienced only reversed symptoms were remarkably similar to those who had had only typical symptoms. The fluctuating-symptom group had high rates of comorbidity, substance abuse, and health care utilization. CONCLUSIONS: Several popular beliefs about depression with reversed features did not hold true for this community sample. Identifying individuals who fluctuate between reversed and typical episodes may be important in studies of major depression, in particular when reversed neurovegetative symptoms are a consideration.

Adolescent↗
PubMed1976

Effect of normal and reversed sleep-wake cycles upon nyctohemeral rhythmicity of plasma thyrotropin: evidence suggestive of an inhibitory influence in sleep.

The relation of nyctohemeral variation in plasma TSH to sleep-wake cycles was examined in 10 normal young men who had their sleep polygraphically monitored and their blood sampled every 20 min for 24,36, or 48 h periods. Studies of normal sleepwake cycles in which sleep was allowed from the usual bedtime to 0630 h totalled 21 nights (night = 1840-0620 h) and their corresponding 16 days. TSH was measured by a sensitive RIA. On 17 nights, the mean nightly TSH significantly exceeded that of the day's and, on 18 nights, clear nyctohemerally maximal peaks in TSH were seen in the 2100-0100 h interval. Greater amplitude, duration and rhythmic repetition over several nights distinguished 2100-0100 h maxima from a background of persistent briefly episodic release. These nyctohemeral peaks were pre-sleep maxima, as rises uniformly began, and on 15 nights, the peaks occurred prior to the onset of sleep. The peaks clustered within the 30 min just before (12 nights) or after (3 nights) entry into sleep. TSH release then declined across sleep. Other evidence suggestive of an inhibitory influence in sleep upon TSH release was that sleep began early on the 3 nights without clear 2100-0100 h TSH maxima and that the mean 2100-0100 h TSH peak was significantly reduced when sleep began prior to the usual 2300-0000 h interval and significantly increased when the onset of sleep was delayed or postponed. After a 24 h baseline, 4 men underwent phase-reversal of their sleep-wake cycles for 48 h, in which sleep was shifted to the 1100-1830 h interval. On the first wakeful night of reversal, the 2100-0100 h peak began normally, but, in the absence of sleep, the enhanced TSH release then simply continued across this night, delaying achievement of the nyctohemeral maxima. On the second wakeful night of reversal, the maximum in mean TSH lay in the same 0400-0600 h interval as that of first reversal night, and the mean 2100-0100 h peak was no longer evident. The TSH of the second 24 h of reversal also was significantly reduced, suggestive of a negative feedback effect of enhanced release of the first reversal day. No shift of basal pre-sleep TSH peaks to the 0900-1300 h interval or of sleep-enhanced TSH release was seen during reversal. Thus, despite the persistence of TSH's nyctohemeral rhythmicity across acute sleep-wake reversal, its pattern changed significantly in relation to shifts in sleep. We currently view these results as consistent with the origin of TSH's nyctohemeral rhythmicity in a circadian mechanism whose expression is subject to modulation by the inhibitory influences of feedback and sleep.

Circadian Rhythm↗
PubMed2003

Improvement in enzyme activity and stability by addition of low molecular weight polyethylene glycol to sodium bis(2-ethyl-L-hexyl)sulfosuccinate/isooctane reverse micellar system.

The activity and stability of Chromobacterium viscosum lipase (glycerolester hydrolase, EC 3.1.1.3)-catalyzed olive oil hydrolysis in sodium bis (2-ethyl-l-hexyl)sulfosuccinate (AOT)/isooctane reverse micelles is increased appreciably when low molecular weight polyethylene glycol (PEG 400) is added to the reverse micelles. To understand the effect of PEG 400 on the phase behavior of the reverse micellar system, the phase diagram of AOT/ PEG 400/water/isooctane system was studied. The influences of relevant parameters on the catalytic activity in AOT/PEG 400 reverse micelles were investigated and compared with the results in the simple AOT reverse micelles. In the presence of PEG 400, the linear decreasing trend of the lipase activity with AOT concentration, which is observed in the simple AOT reverse micelles, disappeared. Enzyme entrapped in AOT/PEG reverse micelles was very stable, retaining >75% of its initial activity after 60 d, whereas the half-life in simple AOT reverse micelles was 38 d. The kinetics parameter maximum velocity (Vmax) exhibiting the temperature dependence and the activation energy obtained by Arrhenius plot was suppressed significantly by the addition of PEG 400.

Chromobacterium↗
PubMed2003

[Evaluation of the reverse flow around a worker's body produced by a local exhaust hood].

Recent studies have shown that a reverse flow often occurs in a unidirectional airflow in push-pull ventilation and may transport contaminants from the source into a worker's breathing zone. The same problem may arise in local exhaust ventilation when the contaminant source is located in the worker's wake region. In this study, organic solvent work with local exhaust ventilation was duplicated in a laboratory and the details of the reverse flow around the worker's body produced by the ventilation were experimentally investigated. In order to evaluate the influence of the reverse flow on the exposure of the worker, experiments with a mock-up mannequin (dummy worker) and a local ventilation system which was equipped with an exterior type hood and an enclosure type hood were conducted. The exposure level and the contaminant leakage from the hoods in several conditions were measured by means of a smoke test and tracer gas method. Ethanol vapor was used as a tracer gas. With the exterior type hood, the reverse flow visualized by the smoke was observed in front of the standing dummy worker but could not be observed when the dummy worker was seated. From the tracer gas measurements, it was proved that the exposure due to the reverse flow was not so serious at a capture velocity of > 0.4 m/s, but < 10 ppm contaminant leakage from the exterior hood had been recognized independently of the capture velocity. With the enclosure type hood, exposure due to the reverse flow could be controlled with a capture velocity of > 0.8 m/s. Although the contaminant leakage from the hood due to the reverse flow was not obvious with the enclosure type in any condition, caution should be exercised to prevent exposure when the worker is seated. Regardless of the hood type, the increase in the capture velocity was effective in decreasing exposure due to the reverse flow.

Air Movements↗
PubMed1990

Reversal sign on CT: effect of anoxic/ischemic cerebral injury in children.

A retrospective study was performed to determine the clinical and pathologic features, etiology, and outcome of children with the reversal sign. The reversal sign, a striking CT finding, probably represents a diffuse, anoxic/ischemic cerebral injury. CT features of the reversal sign are diffusely decreased density of cerebral cortical gray and white matter with a decreased or lost gray/white matter interface, or reversal of the gray/white matter densities and relatively increased density of the thalami, brainstem, and cerebellum. Twenty children with the reversal sign were retrospectively analyzed. We divided the patients into three groups: (1) acute reversal, (2) intermediate group, and (3) chronic reversal. There were nine cases of trauma (seven of child abuse); nine hypoxia/anoxia incidents (birth asphyxia, drowning, status epilepticus); one bacterial meningitis; and one degenerative encephalitis. All acute- and intermediate-group patients had respiratory problems requiring ventilator support and intensive care. In five of seven patients who died, autopsy findings were consistent with anoxic/ischemic encephalopathy. Surviving patients have profound neurologic deficits with severe developmental delay. The CT reversal sign carries a poor prognosis and indicates irreversible brain damage.

Brain Edema↗
PubMed1998

Reversion from type 2 diabetes to nondiabetic status. Influence of the 1997 American Diabetes Association criteria.

OBJECTIVE: To determine the incidence and the rate of reversion of type 2 diabetes to a nondiabetic status in the 7- to 8-year follow-up of the San Antonio Heart Study, and to determine the influence of the recent 1997 American Diabetes Association (ADA) criteria for diabetes on these rates. Individuals who revert have been problematic for those developing criteria for the diagnosis of type 2 diabetes. Few studies have addressed this issue using 1979 National Diabetes Data Group/1980 World Health Organization (WHO) criteria. RESEARCH DESIGN AND METHODS: We studied 3,682 Mexican-American and non-Hispanic white men and nonpregnant women who completed both the baseline and follow-up examination of the San Antonio Heart Study. Incidence and reversion rates were calculated using both the 1980 WHO and the 1997 ADA criteria. Risk factors for reversion were identified, and the best fitting model using multiple logistic regression was determined using both the 1980 WHO and the 1997 ADA criteria. RESULTS: Using the 1997 ADA criteria, the age-adjusted incidences of type 2 diabetes for Mexican-American men and women were 10.8 and 12.2%, respectively. For non-Hispanic white men and women, the age-adjusted incidence rates were 5.5 and 5.1%, respectively. Similar age-adjusted incidences were recorded using the 1980 WHO criteria. The reversion rate for individuals with type 2 diabetes was 11.5% using the 1980 WHO criteria and 12.5% using the 1997 ADA criteria. These rates were not significantly different. Numerous risk factors for reversion were identified. The best fitting model, after controlling for age, sex, and ethnicity, included baseline 2-h glucose level, baseline HDL cholesterol, and previous diagnosis of diabetes. The models were the same for both the 1980 WHO and the 1997 ADA criteria. CONCLUSIONS: There was no significant difference in the incidence or the reversion rates for diabetic subjects using either 1980 WHO or 1997 ADA criteria. In addition, the risk factors for reversion were very similar using either set of criteria. The revision of the ADA criteria did not have a significant influence on reversion in this study.

Adult↗
PubMed1991

Mucosal surface area of a reversed intestinal segment in rats.

Only scarce knowledge exists of morphologic changes after antiperistaltic reversal of the small intestine. Previous animal models using a reversed segment of the small intestine after massive intestinal resection have been mostly concerned with assessing absorption. A rat model was therefore developed for the purpose of studying mucosal surface area in the small intestine after reversal of an intestinal segment. A reversal of 10 cm, representing a length of about 10%, was found suitable for the investigation. Marked dilatation of the reversed segment occurred. A pronounced increase in mucosal surface area caused by mucosal hyperplasia was observed. The mucosal surface area in an anastomosed, but not reversed, segment also increased markedly compared with a group undergoing no operation, although less than in the reversed segment. We conclude that a reversed intestinal segment will increase mucosal surface area in an optimal length used for this purpose. This increase is possibly caused by prolonged exposure to intestinal chyme.

Animals↗
PubMed2003

Evaluating the efficacy of habit reversal: comparison with a placebo control.

BACKGROUND: The purpose of this study was to compare the effectiveness of habit reversal with a placebo control as a treatment for chronic nail biting in adults. METHOD: Thirty adults with a chronic nail-biting problem (occurring > or = 5 times/day nearly every day for > or = 4 weeks and causing physical damage or social impairment) were randomly assigned to a placebo control or habit reversal group. Five participants withdrew from the study prior to the completion of treatment. The remaining individuals in both groups received a total of 2 hours of treatment over 3 sessions. Individuals in the habit reversal group (N = 13) received the components of awareness training, competing response training, and social support. Individuals in the placebo control group (N = 12) simply discussed their nail biting. At pretreatment, posttreatment, and a 5-month follow-up, nail length was measured, photographs were taken of the damaged nails and later rated by independent observers, and data on participant depression, anxiety, and self-esteem were obtained. Treatment compliance and acceptability data were collected at posttreatment only. RESULTS: Results showed that habit reversal produced a greater increase in nail length at posttreatment and follow-up when compared with the placebo. Data from the independent raters confirmed these findings. Habit reversal was also viewed as a more acceptable intervention by the participants. At posttreatment, the habit reversal group had increased their nail length by 22% from pretreatment compared with a 3% increase for the placebo group. At follow-up, the habit reversal group maintained a 19% increase in nail length from pretreatment compared with a 0% increase for the placebo group. CONCLUSION: Findings from this study suggest habit reversal is more effective than a placebo control and should be considered a well-established intervention for body-focused repetitive behaviors.

Adult↗
PubMed1998

Protein refolding by reversed micelles utilizing solid-liquid extraction technique.

This article reports that a reversed micellar solution is useful for refolding proteins directly from a solid source. The solubilization of denatured RNase A, which had been prepared by reprecipitation from the denaturant protein solution, into reversed micelles formulated with sodium di-2-ethylhexyl sulfosuccinate (AOT) has been investigated by a solid-liquid extraction system. This method is an alternative to the ordinary protein extraction in reversed micelles based on the liquid-liquid extraction. The solid-liquid extraction method was found to facilitate the solubilization of denatured proteins more efficiently in the reversed micellar media than the ordinary phase transfer method of liquid extraction. The refolding of denatured RNase A entrapped in reversed micelles was attained by adding a redox reagent (reduced and oxidized glutathion). Enzymatic activity of RNase A was gradually recovered with time in the reversed micelles. The denatured RNase A was completely refolded within 30 h. In addition, the efficiency of protein refolding was enhanced when reversed micelles were applied to denatured RNase A containing a higher protein concentration that, in the case of aqueous media, would lead to protein aggregation. The solid-liquid extraction technique using reversed micelles affords better scale-up advantages in the direct refolding process of insoluble protein aggregates.

Acetone↗
PubMedDate not supplied

[Reversible dementia in neurology outpatient clinics].

INTRODUCTION: The dementias are one of the commonest conditions seen in Neurology Clinics. Potentially reversible causes are described amongst the various aetiologies although there are doubts as to whether the use of indiscriminate testing to detect them is worthwhile. OBJECTIVE: In a group of demented persons to determine how many had a potentially reversible condition and how many improved, in a prospective, descriptive study in a Neurology Outpatient Clinic. PATIENTS AND METHODS: Using the Mini-Mental State Examination of Folstein and the DSM-III-R criteria for dementia, 121 demented patients were selected. An ordinary biochemical study was made (vitamin B12, thyroid hormones), serology (lues) and neuroimaging (cerebral CT), and when a potentially reversible condition was found, each case was treated. The patients treated were followed-up periodically for an average of 9.6 months (range 2 to 24 months). RESULTS: A potentially reversible condition was seen in 19.8% of the patients. On prospective evaluation only 3.3% had reversible symptoms and in no case were these completely reversed. Improvement was seen in conditions of depressive pseudo-dementia. CONCLUSIONS: Since some causes of dementia are reversible, the neurologist is obliged to investigate and seek these possible aetiologies. This study should be individualized according to clinical criteria to improve profitability of the complementary tests. Our results suggest that there are doubts as to the usefulness of indiscriminate investigation of possible reversible causes of the cases of dementia referred to Outpatient neurologists.

Aged↗
PubMed1975

Relationship between pulse pressure, arteriosclerosis, and a visual reversal phenomenon.

Varying numbers of Ss were studied on a task producing a perceived reversal in the direction of rotating objects. Ss were required to indicate when reversal in the direction of rotation of the percept occurred for the first time. Low initial reversal time coincided with high pulse pressure which is an indicator or arteriosclerotic processes. The relationship of initial reversal time and pulse pressure existed for all Ss with histories of cerebro-vascular accident, amputees secondary to diabetes mellitus, and many control Ss (a nonpatient group of higher socio-economic and intellectual levels) who had a poor health history regarding high blood pressure and/or diabetes mellitus. In contrast, control Ss with no cardio-vascular or diabetic problems had high initial reversal times or no reversal at all. Initial reversal time was stable over a short as well as longer periods of time. Initial reversal time may be useful as an adjunct in the prognosis of arteriosclerotic pathology.

Adult↗
PubMed2003

Reversal of breast cancer resistance protein-mediated drug resistance by estrogen antagonists and agonists.

Breast cancer resistance protein (BCRP), an ATP-binding cassette transporter, confers resistance to a series of anticancer agents such as SN-38, mitoxantrone, and topotecan. In a previous study, we found that estrogens reverse drug resistance of BCRP-expressing cells. In this study, estrogen antagonists, estrogen agonists, and their derivatives were evaluated for BCRP-reversing activity. First, compounds were tested for effects on the cellular accumulation of topotecan in BCRP-transduced K562 cells (K562/BCRP). Next, these compounds were examined for their ability to reverse SN-38 and mitoxantrone resistance in K562/BCRP cells. Among commercially available estrogen antagonists and agonists tested, diethylstilbestrol showed the strongest BCRP-reversing activity. Diethylstilbestrol increased the cellular accumulation of topotecan and reversed drug resistance in K562/BCRP cells but showed marginal or no effect in parental K562 cells. The reversal activities of estrone and diethylstilbestrol were more prominent for mitoxantrone than for SN-38. Tamoxifen and toremifene were also found to enhance topotecan uptake in K562/BCRP cells. Next, various tamoxifen derivatives were screened for anti-BCRP activity. In the first cycle of screening with 14 compounds, TAG-11 showed the strongest effect. In the second cycle of screening of 25 TAG-11-related compounds, TAG-139 showed the strongest effect. Reversal of SN-38 and mitoxantrone resistance in K562/BCRP cells by TAG-139 was 5-fold stronger than that by estrone. Dose-dependent characteristics of drug resistance reversal with estrone and TAG-139 were very similar, suggesting that estrone and tamoxifen derivatives interact with the same drug-binding site of BCRP. Derivatives of antiestrogens that exhibit no other biological effects promise to be useful in overcoming BCRP-mediated drug resistance.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2005

[HCV genotyping by combination of the Cobas Amplicor HCV 2.0 test and the reverse hybridization Versant HCV Genotype Assay].

Genotyping of hepatitis C virus (HCV) is of relevance to scheduling the treatment of patients with chronic hepatitis C (VHC), making their prognosis and monitoring the treatment efficacy. A set of 62 sera testing HCV RNA positive in Cobas Amplicor HCV 2.0 test (CA) were genotyped using Versant HCV Genotype Assay (LiPA) Bayer, i.e. the reverse hybridization method, with the CA amplified product being directly used in the assay. Fifty-six out of 57 samples reactive in reverse hybridization (92%) were genotyped. One sample showed a profile differing from any genotype, five samples were not reactive and one sample was not tested within this study design. Two out of five non-reactive sera and one non-tested serum could be genotyped by nested PCR based reverse hybridization. It can be concluded that the CA product resulting from one-step HCV RNA amplification is suitable for use in genotyping by reverse hybridization. The CA product based genotyping procedure is easier to perform, less time-consuming and less costly. The nested PCR based procedure could be used for typing of sera with lower HCV concentrations nontypeable with the combination of CA and Versant HCV Genotype Assay. Forty-eight selected samples were typed not only by reverse hybridization but also by a serological kit Murex HCV Serotyping 1-6 Assay (Abbot Murex). Thirty-seven (77%) of these sera, including all of three sera negative in reverse hybridization, appeared typeable by this kit. Although less sensitive, serotyping may be of relevance to typing of sera with low HCV levels or not containing detectable viral NA which are nontypeable by reverse hybridization. Thirty-three sera appeared genotypeable by both of the methods tested with the results being in good agreement. In two cases only the serotyping method revealed one more type of virus (mixed genotype) compared to the reverse hybridization.

Genotype↗
PubMedDate not supplied

Expression pattern of telomerase reverse transcriptase in rectal carcinoma predicts tumor radiosensitivity, local recurrence and disease-free survival.

BACKGROUND/AIMS: Predictive indicators of radiosensitivity in rectal cancer are required in order to avoid unnecessary preoperative radiotherapy. Telomeres are specialized structures at the ends of chromosomes that protect against that such as irradiation. Lower telomerase activity has been reported to be related to radiosensitivity in vitro or vivo. The aim of this study was to examine the possible role of telomerase reverse transcriptase expression, which is correlated to telomerase activity, in determining tumor radiosensitivity, local recurrence, and disease-free survival in patients with rectal carcinomas. METHODOLOGY: We studied 96 cases with advanced rectal carcinoma. In preradiation biopsy specimens of tumor samples, the number of cells stained positive for telomerase reverse transcriptase protein was evaluated by immunohistochemistry. RESULTS: The expression pattern of telomerase reverse transcriptase protein correlated with tumor radiosensitivity (P=0.0007). All tumors that had a high percentage of telomerase reverse transcriptase positive cells were radioresistant. High telomerase reverse transcriptase expression pattern is a predictive marker for high local recurrence or poor survival in patients with rectal cancer (P=0.011, P=0.0005). Telomerase reverse transcriptase expression and histopathological grade were significant prognostic variables for disease-free survival in the multivariate analysis (P=0.0003, P=0.0091). CONCLUSIONS: Telomerase reverse transcriptase raises the predictive possibility of tumor radiosensitivity in rectal cancer. Telomerase reverse transcriptase might be a useful parameter for patient selection for preoperative radiotherapy in rectal carcinoma.

Adenocarcinoma↗
PubMed2005

Patency following vasectomy reversal. Temporal and immunological considerations.

OBJECTIVES: To evaluate the postoperative patency rates of microsurgical vasovasostomy and vasoepididymostomy at various vasectomy reversal time intervals, and to assess the implications of anti-sperm antibodies on results. METHODS: Three hundred and eighty-two patients underwent unilateral or bilateral vasectomy reversal between January 1997 and April 2001 at the Health Clinic, Highgate and Manor House Hospitals, London, United Kingdom. Patients were divided into 4 groups according to the time interval between vasectomy and reversal; less than 5 years, 5-10 years, 10-15 years, and more than 15 years. Data collected included patient's age at time of vasectomy reversal, seminal fluid analysis at 3, 6 and 12 months after surgery, and the presence or absence of anti-sperm antibodies before vasectomy reversal. RESULTS: Mean patient age at the time of reversal was 44.6 years. The mean vasectomy reversal time interval was 12.8 years. Overall patency rate of the patients groups was 62.9% with positive sperm in the ejaculate in 85.3% in the less than 5 years group, 75.3% in the 5-10 years group, 50.3% in the 10-15 years group and 26.9% in the more than 15 years group. Anti-sperm antibodies were positive in 31 patients (9.1%), of whom 12 patients (38.7%) were positive for sperm in the ejaculate. CONCLUSION: Microsurgical vasectomy reversal produces satisfactory patency rates to couples that consider reestablishing their fertility even more than 15 years after vasectomy. The presence of anti-sperm antibodies is associated with negative effects on sperm count, motility, and percentage of abnormal forms.

Adult↗