[Supraventricular tachycardias: therapeutic attitude in 1998].
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Publications and source records attributed to M Zimmermann.
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Recent in vitro studies indicate an involvement of members of the interleukin-1beta converting enzyme (ICE) family of proteases in programmed neuronal cell death. Cell death of hippocampal neurons in animal models of cerebral ischemia and epilepsy shows morphological features of apoptosis and can be prevented by administration of protein synthesis inhibitors suggesting that de novo synthesis of components of the cell death program is necessary for neuronal apoptosis. In the present study we demonstrate by in situ hybridization analysis that expression of CPP-32, an ICE-related protease, is significantly upregulated in CA1 hippocampal neurons following global ischemia induced by cardiac arrest and in hippocampal neurons of the CA3/CA4 region after kainate-mediated epilepsy, respectively. Moreover, an increase in CPP-32-like proteolytic activity was detected in hippocampal extracts 24 h after ischemia using the fluorogenic CPP-32 substrate Ac-DEVD-AMC. Activation of CPP-32 clearly preceded cell death of hippocampal neurons as assessed by in situ end-labelling of nuclear DNA fragments. These results indicate that CPP-32 protease may be activated at both the transcriptional and post-translational level during neuronal apoptosis and that activation correlates with the selective vulnerability of hippocampal pyramidal neurons to ischemic and epileptic insults.
The effect of ischemia on the reactive expression of ecto-5'-nucleotidase in rat brain was studied 6 h and 1, 2 and 7 days after permanent middle cerebral artery occlusion (MCAO). The distribution of 5'-nucleotidase in the infarcted brain was compared to markers for astrocytes (glial fibrillary acidic protein (GFAP)) and microglia (complement receptor type 3, antibody OX42) using histological staining or immunohistochemistry. 5'-Nucleotidase could be associated with reactive astrocytes by immunohistochemistry and with reactive microglia by enzyme histochemistry. In the untreated control 5'-nucleotidase was associated with astrocytes only in the hippocampus and the submeningeal space. After ischemia the enzyme was expressed on reactive astrocytes in the tissue surrounding the volume of infarction. Individual reactive astrocytes were observed 6 h after MCAO and the astrocytic expression became continuously enhanced during the following days. An enzyme histochemical analysis of 5'-nucleotidase activity revealed a postischemic increase in reaction product around the infarcted tissue. Seven days after MCAO a discrete band (0.2-0.4 mm) of reaction product characterized the rim of the infarcted area. This band of activity of 5'-nucleotidase colocalized with a band of immunoreactivity for OX42, indicative of an intense accumulation of 5'-nucleotidase expressing microglia. Our results suggest that ischemia following permanent MCAO results in an upregulation of the capacity for the hydrolysis of nucleotides within the tissue adjacent to the infarcted volume. Nucleotides released from the damaged cells can be hydrolyzed and the adenosine eventually formed may exert neuroprotective functions limiting the extent of damage.
This study was done to investigate the influence of Gram-negative and Gram-positive sepsis on the expression of the three isoforms of nitric oxide synthase (NOS) gene in rat liver and kidney. Male Sprague-Dawley rats were treated with lipopolysaccharide (LPS, 10 mg/kg i.v.) as an in vivo model for Gram-negative sepsis or lipoteichoic acid (LTA, 10 mg/kg i.v.) as an in vivo model for Gram-positive sepsis. Animals were killed 12 h and 24 h after i.v. treatment. NOS mRNA of the three isoforms was determined by RNase protection assay. NOS II gene expression was strongly induced after LPS or LTA treatment in rat liver and kidney, indicating the efficacy of this treatment to induce sepsis. We found no change of NOS I gene expression after LPS or LTA injection in rat liver and kidney. NOS III gene expression was increased about 8-fold 12 h and about 5-fold 24 h after induction of sepsis in the rat liver whereas in the kidney there was no significant increase in NOS III gene expression. After correction for length NOS III mRNA was about 4- and 40-fold more abundant 12 h and 24 h after LPS treatment than NOS II mRNA in the liver, respectively. Twelve and 24 h after LTA treatment NOS III mRNA was about 18- and 140-fold more abundant than NOS II in the liver. These findings suggest that NOS III is an even more potent source of NO than NOS II in the liver after stimulation with LPS or LTA.
Chronic myelomonocytic leukemia (CMML) is a rare hematopoietic malignancy of childhood. To define the clinical and hematologic characteristics of the disease, we performed a retrospective analysis of 110 children given the diagnosis CMML irrespective of karyotype. Median age at diagnosis was 1.8 years. Neurofibromatosis type 1 was known in 14% and other clinical abnormalities in 7% of the children. At presentation, the medium white blood count was 35 x 10(9)/L, with a median monocyte count of 7 x 10(9)/L. Karyotypic abnormalities in bone marrow cells were noted in 36% of the patients, whereas 26% of the children had monosomy 7. Children with monosomy 7 did not differ from those with normal karyotype with respect to their clinical presentation. However, they did display some characteristic hematologic features. Of 110 children, 38 received an allogeneic bone marrow transplant (BMT). The probability of survival at 10 years was 0.39 (standard error [SE] = 0.10) for the BMT group and 0.06 (SE = 0.4) for the 72 patients of the non-BMT group. Platelet count, age, and hemoglobin F at diagnosis were the main predicting factors for the length of survival in the non-BMT group. There is a strong need for a broad agreement on nomenclature in children with myelodysplastic syndromes (MDS). We propose here to use the French-American-British classification for MDS in childhood.
Proto-oncogenes of the fos and jun family are rapidly expressed in the central nervous system following various stimuli. Proto-oncogene encoded nuclear proteins such as c-Fos or c-Jun act as transcription factors that may link neuronal excitation to changes in target gene expression. However, the precise in vivo functions of proto-oncogenes in neuroplasticity are still poorly understood. In the present study the effect of systemically administered c-fos antisense oligodeoxynucleotides (ODNs) on c-Fos and dynorphin protein levels in rat L4 spinal cord has been investigated by immunohistochemistry during carrageenan-induced hindpaw inflammation. Continuous infusion of terminal-phosphorothioated c-fos antisense ODNs by subcutaneously implanted miniosmotic pumps for 3 days sequence-specifically suppressed c-Fos protein expression in dorsal horn neurons by about 50%, while the increase in c-Jun immunopositive nuclei was not affected. Digital image analysis revealed a concomitant decrease in spinal dynorphin immunoreactivity. Moreover, 48 hr after carrageenan injection into one hindpaw plasma protein extravasation was observed in numerous blood vessels in the ipsilateral dorsal horn using intravenously administered Evans Blue. Our results provide further evidence that c-Fos may contribute to the regulation of spinal dynorphin gene expression following noxious stimulation. The local increase in blood-spinal cord barrier permeability during sustained peripheral inflammation may permit penetration of hydrophilic antisense ODNs into the central nervous system.
INTRODUCTION: Almost all patients treated with opioids suffer from constipation. Numerous laxatives are used to overcome the problem, but none has yet been found to yield favourable results in all patients. Several studies have attempted to reverse opioid-induced constipation by the use of oral naloxone. Experiments carried out in rats showed that morphine-induced constipation is reduced by oral naloxone without impairment of antinociception [4]. However, evaluation of clinical studies reveals that there is uncertainty about the dosage regimen (the daily dose of naloxone ranged from 0.5% to about 60% that of morphine) and a lack of larger numbers of patients studied. METHODS: Fifteen patients suffering from opioid-induced constipation participated in the present study. Constipation had been present for 5 to 14 days despite the use of laxatives. According to the results obtained in the animal experiments [4], it was originally planned to administer oral naloxone at a dose ratio of 1:1 with respect to morphine on day 1 and 2; reducing it on day 3 and 4 to one-half and then to one-fourth of the initial dose on day 5 and 6. RESULTS: Twelve patients experienced a strong laxative effect with spontaneous bowel evacuation 1 to 4 h after the first intake of oral naloxone. Three patients had no laxative effects even after repeated doses. Eleven of the 15 patients reported an average loss of 10%-15% of analgesia after oral naloxone as measured by visual analogue scales. Increasing the morphine dose by about 15% restored the previous level of analgesia without reappearance of constipation. Eight of the 12 patients having a laxative effect experienced abdominal cramps, and therefore, the total dose of naloxone was reduced on day 2 to 2%-15% of that originally planned; this dose still produced a laxative effect. Four of the 15 patients had a withdrawal syndrome. A single dose of morphine equivalent to their daily morphine intake abolished the symptoms. DISCUSSION: The medical history of the 3 patients in whom naloxone failed to abolish constipation revealed neurological disturbances. Treatment of these patients included the use of neuroleptics, antiemetics, and other drugs. In this context, it should be noted that oral naloxone can be expected to abolish only opioid-induced constipation. In conclusion, it was found that the treatment of opioid-induced constipation by administration of oral naloxone produced positive results. A controlled study will show, whether the side effects can be minimized by reducing the naloxone dose.
Ventricular late potentials (VLP) have been shown to be independent predictors of arrhythmic events after myocardial infarction. However, many studies have had one or more limitations: limited follow-up period, small study group, possible selection bias, inadequate statistical analysis, or inclusion of patients with previous infarction. The purpose of this study was to assess the long-term prognostic value of VLP in a large group of unselected patients after a first acute myocardial infarction. Time-domain signal averaging was performed in 458 patients (380 male, 78 female, mean age 59 +/- 11 years) a mean of 10 days (range 7 to 13 days) after a first acute myocardial infarction. The overall prevalence of VLP was 20% (90 of 458 patients). By univariate analysis a left ventricular ejection fraction <40% (p = 0.002) and the presence of an occluded infarct-related artery (p = 0.006) were the only statistically significant predictors for the development of VLP. During a median follow-up of 70 months, 21 (5%) patients died suddenly, and 11 (2%) patients had documented sustained ventricular tachycardia. The presence of VLP (p < 0.0001), older age (p = 0.02), and an occluded infarct-related artery (p = 0.045) were the only variables significantly associated with the occurrence of serious arrhythmic events during follow-up. The probability of having no arrhythmic events was 99% at 1 year and 96% at 5 years in the absence of VLP and 87% at 1 year and 80% at 5 years in the presence of VLP (4.6-fold increase in arrhythmic risk; 95% confidence interval: 2.3 to 9.1). VLPs are powerful predictors of serious arrhythmic events in patients after a first acute myocardial infarction, and their prognostic value, although waning with time, persists for at least 7 years. This study also provides further evidence that an open infarct-related artery may reduce the arrhythmic risk after myocardial infarction.
In adult male rats, the expression of the neuropeptide galanin and its co-localization with the c-Jun transcription factor and the NADPH-diaphorase, the marker enzyme for the nitric oxide synthase (NOS), was investigated by immunohistochemistry in axotomized neurons following unilateral stereotaxic transection of the (a) mamillo-thalamic tract, (b) medial forebrain bundle, (c) fimbria fornix bundle and (d) sciatic nerve. This surgical procedure resulted in axotomy of neurons of (a) mamillary ncl. (MnM), (b) substantia nigra compacta (SNC) and paraventricular ncl. of thalamic (PF) neurons, (c) medial septum (MS) and vertical diagonal band of Broca (VDB), and (d) sciatic motoneurons and dorsal root ganglia (DRG). In all of these axotomized neuronal subpopulations, expression of c-Jun appeared between 24 and 36 h post-axotomy and persisted on substantial levels for 15 days in the SNC and for 30-50 days in the MnM, PF, MS, VBD, sciatic DRG and motoneurons. Expression of galanin was seen in axotomized MnM, MS and DRG, but not in SNC, PF and sciatic motoneurons. Galanin-immunoreactivity (IR) appeared between 3 and 5 days after nerve fiber transection and persisted up to 50 days in the MnM, MS and DRGs. The cytoplasmic galanin-IR was almost completely restricted to those neurons showing a nuclear c-Jun expression. Moreover, galanin expression showed a long-lasting co-localization with those neurons that exhibited an increased NADPH-diaphorase reactivity in the MnM and DRG or a residual NADPH-diaphorase reactivity in MS post-axotomy. Very similar to galanin, NADPH-diaphorase was not affected by axotomy in the SNC, PF or sciatic motoneurons. Our findings suggest a common mechanism for galanin and NOS (NADPH-diaphorase activity) expression. Since the galanin promotor contains an AP-1 binding site, c-Jun might trigger the lasting induction of galanin in NOS-positive central neurons that survive the axotomy-evoked injury.
In anesthetized cats, recordings were obtained from single lumbar dorsal horn neurons and from primary afferent fibers of the posterior tibial nerve excited by controlled noxious radiant heating of glabrous hindpaw skin. Electrical stimulation in four brain stem regions (periaqueductal gray and lateral reticular formation in the midbrain, raphe and reticular formation in the medulla) during noxious skin heating markedly reduced the nociceptive excitation of the dorsal horn neurons. In contrast, such brain stem stimulation had small and variable effects upon the noxious heat-evoked activity in the primary afferent fibers; both increases and decreases were observed. The brain stimulation also produced transient changes in blood pressure, suggesting that circulatory effects may underlie the mechanism of nociceptor modulation. It is concluded that brain stem stimulation can modulate cutaneous nociceptor activity, but that this modulatory effect on nociceptor inflow is too small and inconsistent to explain the marked descending inhibition of the nociceptive excitation of dorsal horn neurons.
The expression of the constitutive transcription factors activating transcription factor-2 (ATF-2), serum response factor (SRF) and cAMP/Ca response element binding factor (CREB), and the phosphorylation of SRF and CREB were studied in the untreated adult rat nervous system and following seizure activities and neurodegenerative stimuli. In the untreated rat, intense nuclear SRF immunoreactivity was present in the vast majority of neurons in the forebrain, cortex, striatum, amygdala and hippocampus, and in some scattered neurons in the medulla and spinal cord. In contrast, SRF immunoreactivity was absent in the midline areas of the forebrain, e.g., the globus pallidum and septum, and in the hypothalamus, thalamus, mesencephalon and motoneurons. Nuclear ATF-2 was expressed at high levels in apparently all neurons, but not glial cells, throughout the neuraxis except for those neuronal populations which exhibit a high basal level of c-Jun, i.e. dentate gyrus and the motoneurons of cranial and somatosensory neurons. CREB immunoreactivity was present at a rather uniform intensity in all neuronal and glial cells throughout the neuraxis. Two hours, but not 5 h or 24 h, following systemic application of kainic acid, an increase in SRF was detectable by western blot analysis in hippocampal and cortical homogenates whereas the expression of ATF-2 and CREB did not change. Phosphorylation of CREB at serine 133 and of SRF at serine 103 were studied with specific antisera. In untreated rats, intense phosphoCREB and phosphoSRF immunoreactivities labelled many glial cells and/or neurons with the highest levels in the dentate gyrus, the entorhinal cortex and the retrosplenial cortex. Following kainate-induced seizures, phosphoSRF-IR but not phosphoCREB-IR transiently increased between 0.5 h and 2 h. Following transection of peripheral or central nerve fibres such as optic nerve, medial forebrain bundle, vagal and facial nerve fibres, ATF-2 rapidly decreased in the axotomized neurons during that period when c-Jun was rapidly expressed. SRF remained unchanged and CREB disappeared in some axotomized subpopulations. Similar to axotomy, c-Jun increased and ATF-2 decreased in cultured adult dorsal root ganglion neurons following ultraviolet irradiation. The distribution of SRF and ATF-2 suggests that their putative target genes c-fos, junB, krox-24 and c-jun can be independently regulated from SRF and ATF-2. The suppression of ATF-2 and the expression of c-Jun following axotomy and ultraviolet irradiation might be part of a novel neuronal stress response in the brain that strongly resembles the stress response characterized in non-neuronal cells.
In the present study we have demonstrated that the same aversive stimulus induces different patterns of expression of transcription factors in the hippocampus and septum of male and female rats. We have investigated by immunohistochemistry the effects of a persistent painful stimulus and restraint stress on c-Fos expression in the hippocampus and septum of male and female rats. Subjects were randomly assigned to one of three experimental groups: (i) untreated controls, (ii) subcutaneous injection with formalin (50 microliters, 10%) in the right hindpaw, or (iii) immobilization in an adjustable restrainer. Formalin-treated and restrained animals were killed 90 min after the beginning of treatment. In both male and female rats, unilateral injection of formalin induced bilateral c-Fos expression in the hippocampus, but the number of labeled neurons was two-fold higher in females than in males. Restraint stress was not effective in c-Fos induction in the hippocampus of both sexes. In the septum, both treatments increased c-Fos, but this increase tended to be greater in males than females. Previous experiments have consistently shown that male and female rats react differently to aversive stimulation. The present findings suggest that hormonal and behavioral differences between the sexes are accompanied by genetic modifications in those brain areas involved in cognition and emotion.
The aim of the multicentre study entitled 'Description and Documentation of Painful States in Spinal Cord Injury Patients', in addition to the description and documentation of chronic pain and stressful dysaesthesiae in SCI patients, was the search for correlations between these symptoms and medical and psychosocial variables. To this end, the sample was selected to be as representative as possible. All patients referred for in-patient or out-patient treatment at the centres taking part were enrolled in the study in order of presentation, providing they gave consent and met the inclusion criteria. Psychosocial, medical and demographic data were elicited by a standardized battery of questions and a standardized physical examination, as were any chronic pain/dysaesthesiae (P/D) present in any localization. Among 901 patients, 34% had no chronic pain or dysaesthesiae, 50% had pain only, 11% had painful dysaesthesiae and 5%, non-painful but chronic and distressing dysaesthesiae. The intensity of P/D was noted as seven or more on a 10 cm visual analogue scale by 61% of the patients affected and was experienced as rather or very distressing in 75% of cases. Most (86%) P/D were located below the spinal lesion or in the transition zone. There were significant correlations between the presence of P/D and age on questioning and at onset of the paraplegia/tetraplegia, problems with rectal paralysis, expectations of life as a paraplegic/tetraplegic, and subjective assessment of changes in working life. Highly significant correlations were found with subjective distress resulting of paraplegia/tetraplegia as such, depressed mood and psychosomatic disturbances of wellbeing. Overall, among the selected variables of our study, we found that correlations between P/D and psychosocial variables were more frequent and closer than those between P/D and medical variables.
Dystrophic epidermolysis bullosa (EBD) is a clinically heterogeneous skin disorder, characterized by abnormal anchoring fibrils (AF) and loss of dermal-epidermal adherence. EBD has been linked to the COL7A1 gene at chromosome 3p21 which encodes collagen VII, the major component of the AF. Here we investigated two unrelated EBD families with different clinical phenotypes and novel combinations of recessive and dominant COL7A1 mutations. Both families shared the same recessive heterozygous 14 bp deletion at the exon-intron 115 boundary of the COL7A1 gene. The deletion caused in-frame skipping of exon 115 and the elimination of 29 amino acid residues from the pro-alpha1(VII) polypeptide chain. As a result, procollagen VII was not converted to collagen VII and the C-terminal NC-2 propeptide which is normally removed from the procollagen VII prior to formation of the anchoring fibrils was retained in the skin. All affected individuals also carried missense mutations in exon 73 of COL7A1 which lead to different glycine-to-arginine substitutions in the triple-helical domain of collagen VII. Combination of the deletion mutation with a G2009R substitution resulted in a mild phenotype. In contrast, combination of the deletion with a G2043R substitution led to a severe phenotype. The G2043R substitution was a de novo mutation which alone caused a mild phenotype. Thus, different combinations of dominant and recessive COL7A1 mutations can modulate disease activity of EBD and alter the clinical presentation of the patients.
We describe a patient with severe generalized dystrophic epidermolysis bullosa (EBD) and a novel combination of compound heterozygous mutations in the COL7A1 gene. The maternal mutation was an A-to-G transition (425-A --> G) at position -2 of the donor splice site within exon 3 that causes aberrant splicing of two abnormal transcripts. One includes intron 3, and one excludes both exon 3 and intron 3. Both splice variants contained a premature termination of the translation. The paternal mutation is a 25-bp deletion in exon 20 (2638de125) that leads to a frameshift and a premature termination codon 133 bp downstream from the site of deletion. This combination of mutations allowed expression of collagen VII mRNA. Immunofluorescence staining of the patient's skin and cultured keratinocytes with domain-specific collagen VII antibodies, however, demonstrated markedly reduced levels of alpha1(VII) polypeptides, and no stable collagen VII protein could be extracted from the patient's cells. Electron microscopy showed severely hypoplastic fibrils below the lamina densa, without evidence of normal anchoring fibrils. The clinically unaffected parents were heterozygous for the mutations, suggesting that both COL7A1 gene defects were recessively inherited disease-causing mutations that are "silent" in heterozygous carriers but in combination can severely interfere with the dermal-epidermal adhesion and lead to severe EBD.
PURPOSE: To evaluate the role of allogeneic bone marrow transplantation (BMT) in children with chronic myelomonocytic leukemia (CMML). PATIENTS AND METHODS: Forty-three children with CMML given BMT and reported to the European Working Group on Myelodysplastic Syndrome in Childhood (EWOG-MDS) data base were evaluated. In 25 cases, the donor was a human leukocyte antigen (HLA)-identical or a one-antigen-disparate relative, in four cases a mismatched family donor, and in 14 a matched unrelated donor (MUD). Conditioning regimens consisted of total-body irradiation (TBI) and chemotherapy in 22 patients, whereas busulfan (Bu) with other cytotoxic drugs was used in the remaining patients. RESULTS: Six of 43 patients (14%), five of whom received transplants from alternative donors, failed to engraft. There was a significant difference in the incidences of chronic graft-versus-host disease (GVHD) between children transplanted from compatible/one-antigen-mismatched relatives and from alternative donors (23% and 87%, respectively; P < .005). Probabilities of transplant-related mortality for children given BMT from HLA-identical/one-antigen-disparate relatives or from MUD/ mismatched relatives were 9% and 46%, respectively. The probability of relapse for the entire group was 58%, whereas the 5-year event-free survival (EFS) rate was 31%. The EFS rate for children given BMT from an HLA-identical sibling or one-antigen-disparate relative was 38%. In this latter group, patients who received Bu had a better EFS compared with those given TBI (62% v 11%, P < .01). CONCLUSION: Children with CMML and an HLA-compatible relative should be transplanted as early as possible. Improvement of donor selection, GVHD prophylaxis, and supportive care are needed to ameliorate results of BMT from alternative donors.
PURPOSE: The ALL-BFM 90 and AIEOP-ALL 91 studies share the same treatment backbone and have 5-year event-free survival (EFS) rates close to 75%. This study evaluated the impact of differing presymptomatic CNS therapies in T-cell acute lymphoblastic leukemia (T-ALL) patients with a good response to prednisone (PGR) according to WBC count and Berlin-Frankfurt-Münster (BFM) risk factor (RF). PATIENTS: A total of 192 patients (141 boys; median age, 7.5 years) with T-ALL, PGR, RF less than 1.7, and no CNS leukemia diagnosed between 1990 and 1995 were enrolled onto the ALL-BFM 90 (n = 123) or AIEOP-ALL 91 (n = 69) study. Presymptomatic CNS therapy consisted of cranial radiation (CRT) and intrathecal methotrexate (I.T. MTX) (11 doses) in the BFM study and of extended triple intrathecal therapy (T.I.T.) (17 doses) in the Associazione Italiana Ematologia Oncologia Pediatrica (AIEOP) study. Patients were divided into a low-WBC group (WBC count < 100,000/microL) and a high-WBC group (WBC count > 100,000/microL). EFS was compared using the log-rank test. RESULTS: For patients treated with CRT and I.T. MTX (BFM group), the 3-year EFS rate was 89.8% (SE = 3.5) for 99 patients in the low-WBC group versus 81.9% (SE = 8.2) in the high-WBC group (difference not significant). Conversely, for patients treated with T.I.T. alone (AIEOP group), the EFS rate was 80.6% (SE = 5.6) in 55 patients with a low WBC count versus 17.9% (SE = 11.0) in 14 patients with a high WBC count (P < .001). CONCLUSION: These data suggest that CRT may not be necessary in PGR T-ALL patients with a WBC count less than 100,000/microL; on the contrary, in patients with a high count, extended T.I.T. may be inferior to CRT and I.T. MTX.
BACKGROUND: To determine if routine semen culture is useful in asymptomatic couples joining an in-vitro fertilization (IVF/ET) program. METHODS: Bacterial cultures and semen analysis according to WHO recommendations were performed on semen samples obtained before oocyte recovery from 88 asymptomatic couples undergoing IVF during a 7-month period. RESULTS: In 46 cultures at least one kind of microorganisms could be isolated. Forty-two cultures either contained bacterias regarded as normal skin flora (n = 14) or showed no growth of microorganisms (n = 28). No differences were found in sperm concentration, total sperm count and sperm morphology between the semen samples with positive bacteriology and those with negative culture results. Sperm motility was decreased before Percoll preparation if microorganisms were present. Positive culture results had no effect on either fertilization or pregnancy rates. CONCLUSIONS: These observations suggest that bacteriospermia is not associated with abnormal sperm function after Percoll preparation or adverse IVF outcome.