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J Arends

Publications and source records attributed to J Arends.

At least 19 recordsLinked to original sources
PubMed2006

The association between HTR2C polymorphisms and obesity in psychiatric patients using antipsychotics: a cross-sectional study.

The use of antipsychotics is associated with an increased risk of obesity. This consideration makes it important to search for determinants that can predict the risk for antipsychotic-induced obesity. In this cross-sectional study, we investigated whether polymorphisms in the HTR2C gene were associated with obesity (body mass index >30 kg/m2) in patients using antipsychotics. We examined polymorphisms in the promoter region of the HTR2C gene ((HTR2C:c.1-142948(GT)n, rs3813928 (-997 G/A), rs3813929 (-759 C/T), rs518147 (-697 G/C)) and an intragenic polymorphism (rs1414334:C>G). The results of the logistic regression were expressed as adjusted odds ratios (OR). In total, we included 127 patients mainly diagnosed with schizophrenia or schizoaffective disorder (89%). The results indicate that a combined genotype carrying the variant HTR2C:c.1-142948(GT)n 13 repeat allele, the common allele rs3813929 C, the variant allele rs518147 C and the variant allele rs1414334 C is significantly related to an increased risk of obesity (OR 3.71 (95% confidence interval: 1.24-11.12)).

Adult↗
PubMed2006

ESPEN Guidelines on Enteral Nutrition: Non-surgical oncology.

Enteral nutrition (EN) by means of oral nutritional supplements (ONS) and tube feeding (TF) offers the possibility of increasing or ensuring nutrient intake in cases where normal food intake is inadequate. These guidelines are intended to give evidence-based recommendations for the use of ONS and TF in cancer patients. They were developed by an interdisciplinary expert group in accordance with officially accepted standards, are based on all relevant publications since 1985 and were discussed and accepted in a consensus conference. Undernutrition and cachexia occur frequently in cancer patients and are indicators of poor prognosis. EN should be started if undernutrition already exists or if food intake is markedly reduced for more than 7-10 days. Standard formulae are recommended for EN. Nutritional needs generally are comparable to non-cancer subjects. In cachectic patients metabolic modulators such as progestins, steroids and possibly eicosapentaenoic acid may help to improve nutritional status. EN is indicated preoperatively for 5-7 days in cancer patients undergoing major abdominal surgery. During radiotherapy of head/neck and gastrointestinal regions dietary counselling and ONS prevent weight loss and interruption of radiotherapy. Routine EN is not indicated during (high-dose) chemotherapy.

Cachexia↗
PubMed2006

Epidemiology of multiple Acinetobacter outbreaks in The Netherlands during the period 1999-2001.

An increase in the number of outbreaks of Acinetobacter infection was notified in The Netherlands during 1999-2001. The present study compared the outbreaks at the species and strain levels, and analysed the epidemiology and control measures at the different locations. For each institute, three representative isolates from three patients were identified to the species and strain levels by genotyping methods. A questionnaire investigated the impact of the outbreak, the control measures that were taken, and the possible effects of the measures. Seven outbreaks were associated with Acinetobacter baumannii (three outbreaks with a strain designated strain A, two outbreaks with a strain designated strain B, and one outbreak each with strains designated C and D). An additional outbreak was caused by genomic species 13TU, which is related closely to A. baumannii. Strains B and D were identified as European clones III and II, respectively. Except for two hospitals with outbreaks caused by strain A, there was no known epidemiological link between the participating hospitals. In all hospitals the outbreak occurred on one or several intensive care units, and spread to other departments was noted in two hospitals. The number of patients affected ranged from six to 66 over a period of 2-22 months. In most outbreaks, patients were the likely reservoir from which spread occurred. In all hospitals, a large panel of measures was required to bring the outbreak to an end. Extensive environmental sampling yielded numerous positive samples in most but not all hospitals.

Acinetobacter↗
PubMed2004

Topiramate in clinical practice: long-term experience in patients with refractory epilepsy referred to a tertiary epilepsy center.

For the treatment of patients with chronic refractory epilepsies, information about the long-term efficacy and safety profile of any new antiepileptic drug is crucial. Topiramate has been proven to be effective in patients with refractory chronic partial epilepsies in short-term controlled clinical trials, but the long-term retention, long-term efficacy, and long-term side-effect profile have not been sufficiently investigated. We analyzed all patients who had been treated with topiramate in the Epilepsy Centre Kempenhaeghe from the introduction of the drug in the spring of 1993 up to a final assessment point in mid-2002. In total, 470 patients were identified. The data show that the clinical dose achieved was about 200mg/day, reached after approximately 6 months of treatment. Further dose escalation in the survivors was slow, with a mean dose of about 300 mg/day after 24 months of treatment. Mean titration dose is 25mg/week, but titration strategy is mostly individual and responds to patient complaints. With respect to seizure frequency, 10-15% of the patients were seizure-free at the 6-month evaluation; 4 patients achieved a 2-year remission. Retention rate was 53% after 1 year, 45% after 2 years, 38% after 3 years, and 30% after 4 years. At 4 years, almost 70% of the patients had discontinued topiramate. The main reason was adverse events, which accounted for about 65% of the discontinuations. Behavioral side effects were dominant, with mental slowing (27.6%), dysphasia (16.0%), and mood problems (agitation: 11.9%) being the most frequently reported side effects. In about 10% of the patients side effects led to discontinuation despite the obvious favorable effects on seizure frequency. Comparisons between the patients who discontinued topiramate treatment and those who continued topiramate showed that discontinuation was associated with comedication (vigabatrin and lamotrigine). Our conclusion is that TPM is associated with a high incidence of side effects in clinical practice, affecting long-term retention. Meaningful prognostic factors that may help us in clinical decision making, i.e., to prevent the side effects or to help us identify those at risk, have not been found.

Adolescent↗
PubMed2004

The cognitive impact of epileptiform EEG-discharges; relationship with type of cognitive task.

In this study we analyzed the effect of differing task dimensions (high vs. low information demand; short vs. long testing duration) on the occurrence of epileptiform EEG-discharges and the cognitive impact of such discharges. We performed this study only in patients with focal discharges as this appears to be the most complicated group to assess any relationship between epileptiform EEG-discharges and cognitive impairment. Seventeen patients with focal discharges in the EEG and an established diagnosis of localization-related (partial) epilepsy were included. The following tasks were used: Low information demand: auditory and visual RT; high information demand: BCRT and CVST. Short testing duration: Arithmetic and Reading; long testing duration: Vocabulary and Block Design. The percentage of patients with epileptiform EEG-discharge and EEG-related cognitive impact were compared using Chi-square testing. The occurrence of epileptiform EEG-discharges was not associated with one of the experimental conditions introduced in our study, that is, high/low information demand or short/long testing period. Also the difference between computerized reaction-time measurement and more traditional 'paper and pencil tasks' such as reading was not statistically significant. The only statistical significant difference was the more frequent occurrence of epileptiform EEG-discharges during tasks that used the visual input mode. In addition, we could identify one test that appeared to be particularly sensitive to direct cognitive effects of epileptiform EEG-discharges. Only for the CVST, the computerized visual searching task, the relationship with epilepsy-related cognitive impact is statistically significant. This test is the most mentally demanding test of the tests presented in our study and measures speed of visual information processing, using complex stimulus patterns and has a long testing duration. Our results do not confirm that any of the investigated task dimensions (high vs. low information demand; short vs. long testing duration) have a dominant effect on the occurrence of epileptiform EEG-discharges and the cognitive impact of such discharges. The effect found for the CVST suggest that three factors combined are necessary to assess the impact of epileptiform EEG-discharges on cognition: visual input mode, longer testing duration and high information processing demand.

Auditory Perception↗
PubMed2003

Multiple primary malignancies in osteosarcoma patients. Incidence and predictive value of osteosarcoma subtype for cancer syndromes related with osteosarcoma.

The overall incidence of osteosarcoma is low. However, the occurrence of osteosarcoma in a setting of multiple primary tumours is not infrequent, although population-based incidence numbers are unknown. The occurrence of osteosarcoma and other malignancies is frequently related to treatment, and can also be the result of genetic predisposition as in patients with retinoblastoma, Li-Fraumeni syndrome, Werner syndrome and Rothmund-Thomson syndrome. The aim of our study is to establish the incidence of osteosarcoma associated with other malignancies in a populationwide study and to find out if these osteosarcomas have a specific subtype, that could draw attention to a genetic predisposition to malignancy. A list of all patients registered in the Dutch National Pathology Register, named PALGA, with a diagnosis of osteosarcoma between 1975 and May 2000 was retrieved. All patients with another malignancy besides osteosarcoma were selected. All patients registered in the same period with a tonsillectomy served as a control for the occurrence of malignancy in a normal population. In a second step, only osteosarcoma patients with a history of retinoblastoma or a malignancy before the age of 46 years, since these are most probable to have a hereditary cancer syndrome, were retained for further analysis. The osteosarcomas were subtyped as common, chondroblastic, fibroblastic, teleangiectatic, anaplastic, osteoclast-rich or small cell. As a control for osteosarcoma subtypes the data of 570 patients entered in two studies from the European Osteosarcoma Intergroup (EORTC/MRC) were used. Of all 938 patients registered with the diagnosis of osteosarcoma, 66 had a history of multiple primary tumours. Four patients had a surface osteosarcoma, three an extraskeletal osteosarcoma and 59 had intramedullar high-grade osteosarcoma. Of this last group, one patient was known with Rothmund-Thomson syndrome, one had retinoblastoma and 30 had their malignancies before the age of 46. Of these 32 patients, 17 had osteosarcoma of the long bones. Especially women seem to be more susceptible for the development of multiple primaries. In nine patients, the histological subtype could be assessed by revision of available histological slides. All of these patients had an osteosarcoma subtype other than common as opposed to 29% in the control group of the European Osteosarcoma Intergroup. It is concluded that although the incidence of osteosarcoma is low, the occurrence of another malignancy in osteosarcoma patients is higher than in the normal population. Specifically, osteosarcoma patients have a relative risk of 2.4 (95% confidence interval 1.88-3.07) to develop another malignancy. A noncommon subtype of osteosarcoma should draw attention to a possible genetic predisposition of the patient involved.

Adolescent↗
PubMed2002

Randomized double-blind parallel-group study comparing cognitive effects of a low-dose lamotrigine with valproate and placebo in healthy volunteers.

PURPOSE: This study aimed at investigating the cognitive and mood effects of lamotrigine (LTG) versus valproate (VPA) and placebo (PBO). METHODS: By studying the effects in healthy volunteers, it is possible to separate the genuine effects of LTG from the cognitive improvements, caused by better seizure control. The study used a pretest-posttest comparison of 50 mg LTG, 900 mg VPA, or PBO in a double-blind single-dummy parallel-group design with 30 healthy volunteers. Study duration was 12 days (with a last control on day 13). Outcome measures included cognitive tests (FePsy neuropsychological test battery), mood scales (ASL; mood-rating scale), and a scale for subjective complaints (ABNAS Neurotoxicity scale). Total sleep time was controlled with actigraphic recordings. The results were analyzed by comparing the change over time (pretest with posttest) for the three treatments with Student's t tests. RESULTS: COGNITIVE TESTS: significant differences between the treatments were found for measurements of cognitive activation (i.e., three of the four simple reaction-time measurements showed statistically significant differences in change between PBO and LTG in favor of LTG (p=0.03; 0.03; 0.04); two of four tests showed statistically significant differences in change between LTG and VPA, both in favor of LTG (p=0.03; 0.05). SUBJECTIVE COMPLAINTS: the ABNAS-neurotoxicity scale reveals a significant reduction of drug-related cognitive complaints for the subjects taking LTG, relative to VPA (p=0.02). MOOD RATING: significant changes were found on the scale assessing "tiredness," showing increased tiredness/sedation for VPA relative to PBO (p=0.02) and on the "timid scale" for LTG reporting "being more at ease" compared with both PBO and VPA (p=0.02; 0.02). The general direction of change for the mood scales was toward "activation" for LTG (five of six scales improved), whereas for VPA, the reverse effect was found (four of six scales showed a change in the direction of "tiredness/sedation"). CONCLUSIONS: Short-term treatment in normal volunteers with a low dose of LTG resulted in improved cognitive activation on simple reaction-time measurements, a more positive subjective report about the impact of drug treatment relative to VPA, and mood changes concurring with the activating effect demonstrated by the cognitive tests.

Adult↗
PubMed2001

Excellent response to gemcitabine in a massively pre-treated woman with extensive cutaneous involvement after recurrence of breast cancer.

A 50-year-old woman presented with local relapse of breast cancer 6 years after partial mastectomy. Relapse was accompanied by extended skin induration due to tumor cell embolization of dermal lymphatics. During the following years the patient was exposed to 11 different anti-tumor regimens including 13 cytotoxic drugs (including alkylating agents, antitumor antibiotics, vinca alcaloids, epipodophyllotoxins, and taxanes), 4 anti-hormonal, and 2 immunologic attempts. Paclitaxel achieved a prolonged local improvement for some 7 months, but further various treatments were ineffective. At that time gemcitabine therapy was initiated and tumor infiltration of the skin was visibly diminished only 2 weeks later. After that tumor regressed further for 5 months and remained stable with continued doses of gemcitabine during much of the woman's last year. The patient died of acute myeloid leukemia (AML) 4 years after the local recurrence of breast cancer. Since multiple treatments using a plethora of aggressive cytotoxic drugs may render several classes of chemotherapy agents ineffective due to cross-resistance, it seems advisable to select mild agents that are not subject to multidrug resistance mechanisms and display a unique mode of action as demonstrated in this case by gemcitabine.

Antimetabolites, Antineoplastic↗
PubMed2001

Acute cognitive effects of nonconvulsive difficult-to-detect epileptic seizures and epileptiform electroencephalographic discharges.

This study compares the acute cognitive effects of short nonconvulsive seizures with the effects of interictal epileptiform electroencephalographic (EEG) discharges in children. The study is a prospective, standardized, nonrandomized, and open clinical comparative study. Eligible patients were included when they had (a) unclear seizures and fluctuations in cognitive performance and (b) frequent epileptiform EEG discharges in a recent EEG. All children were assessed with EEG/video (Brainlab) simultaneously with computerized neuropsychologic testing (FePsy) assessing motor speed/alertness, mental speed/attention, and memory function. Eleven patients with short nonconvulsive seizures during cognitive testing were included and compared with 11 matched patients with interictal epileptiform EEG discharges during cognitive testing but without seizures. Patients included in both groups had a reconfirmed diagnosis of epilepsy. Cognitive performance for both groups was compared. Statistical analysis showed significant correlations between the number of seizures (during cognitive testing) and impaired alertness and between the duration of the ictal period and memory impairment. Interictal epileptiform EEG discharges do not have an additional independent effect on cognitive function. The results demonstrate the accumulating cognitive effect of seizures and illustrate that frequent seizures, even when these are short in duration and with subtle symptomatology, can have a substantial impact on daily life and can lead to state-dependent learning impairment. Alertness and short-term memory appeared to be the functions that are most vulnerable for the acute effects of seizures.

Brain↗
PubMed2000

Effects of a combined thermochemotherapy on markers of apoptosis, differentiation and adhesion in the human mammary carcinoma MX-1. A light microscopic and immunohistochemical study.

The susceptibility to apoptotic stimuli, the degree of differentiation and the adhesive properties are important determinants of a tumor's biological behavior and of the possibility of it's being influenced by treatment. In this study we examined the effects of a combined thermochemotherapy, consisting of the administration of the alkylating agents ifosfamide or mafosfamide combined with hyperthermia at 41 degrees C for one hour, applied to the human mammary carcinoma MX-1. We concentrated our observations on the apoptosis-associated proteins bax and bcl-2, on cytokeratin and vimentin as markers of differentiation, on desmosomes and on the antiadhesive epithelial membrane antigen episialin. These proteins were visualized immunohistochemically in cultured cells in vitro as well as in xenotransplants growing in nude mice in vivo. We found that the susceptibility of the surviving cells to apoptotic stimuli, measured by the bax/bcl-2 ratio, was much higher after a combined thermochemotherapy than after chemotherapy or thermotherapy alone. Many of these cells could probably be forced into apoptosis by later applying another kind of anticancer therapy. With regard to the expression of episialin after thermochemotherapy, fewer cells possessed an antiadhesive and, therefore, potentially invasive capacity. The number of desmosomes seemed not to be affected. As to their higher expression of cytokeratin and their unchanged expression of vimentin, the surviving cells appear to be more differentiated. Since these results could be observed in vivo as well as in vitro, it seems likely that, apart from its influence on the perfusion of the tumor, the amplification of the cytostatic efficacy of the chemotherapy by hyperthermia must be mediated by a direct mechanism.

Animals↗
PubMed1999

An open, nonrandomized clinical comparative study evaluating the effect of epilepsy on learning.

Children with epilepsy, as a group, have a greater risk for developing learning problems as comorbid disorders. It is unknown which factors contribute to the development of such learning problems; therefore, our current knowledge does not allow the prediction of educational delay in an individual child with epilepsy. This study aimed at excluding as many factors as possible that could interfere with the analysis of the impact of epilepsy on learning. From patients referred to us in 1997 (N = 123), children were included with mild global learning impairment, defined as educational delay between 6 months and 1 year and no other apparent reason for learning impairment except for epilepsy (ie, excluding children with dyslexia, attention-deficit hyperactivity disorder, or mental handicap). A total of 44 patients fulfilled this criterion: 31 also had epilepsy (experimental group); the remaining 13 patients with similar mild learning impairment but without epilepsy were used as controls. In the experimental group two subgroups were distinguished on the basis of onset of learning impairment: in group A (n = 17) the learning problems are not unexpected as they were preceded by mild developmental delay; in group B (n = 14) the problems are unexpected and had a sudden onset. The two experimental groups differed from the control group on a number of variables, such as gender and the incidence of perinatal complications. More differences have been found between the two experimental groups: group B is selected from a larger group: all children with mild global learning impairment with sudden onset. In this group considerably more children with epilepsy have been found compared to the children with developmental delay; moreover the epilepsy is more often characterized in these children as "unexpected," that is, there was no previous established diagnosis of epilepsy, the symptoms were mostly unclear and behavioral in make-up (attentional lapses, etc); the electroencephalogram plays a much greater role in the diagnosis in this group, especially in demonstrating seizures; finally, the children in this group more frequently have neuropsychologic impairment. Children with epilepsy can have mild global learning difficulties, especially in the period after the onset of seizures. This group can be divided in a group with "trait-dependent learning difficulties," that is learning difficulties based on developmental delay, and a group with "state-dependent learning difficulties." The focus in our study was on this latter group, consisting of children with sudden and unexpected decline of results in school. The crucial finding in this group is the relatively frequent demonstration of difficult-to-detect seizures, demonstrating that an uncontrolled epilepsy can cause a decline in school results even when the seizures are of short duration and have subtle symptoms.

Attention Deficit Disorder with Hyperactivity↗
PubMed1998

Cariostatic effect of a light-cured, resin-reinforced glass-ionomer for bonding orthodontic brackets in vivo. A combined study using microradiography and confocal laser scanning microscopy.

The aim of this study was to evaluate in vivo the cariostatic potential of the resin-reinforced glass-ionomer (Vitremer core build-up restorative; 3M Dental Product Division) when used as a bonding agent for orthodontic brackets. The mineral distribution and topography of the enamel surface adjacent to the bracket base was determined by quantitative microradiography (TMR) and confocal laser scanning microscopy (CLSM). The study was designed in split-mouth technique using 9 pairs of premolars to be extracted for orthodontic reasons. One tooth of each pair was bonded with the resin-reinforced glass-ionomer, and the control contralateral premolar with the non-fluoridated composite (Concise, 3M Dental Products Division). After 4 weeks all teeth were extracted and stored until analysis. The lesion depths and mineral loss values in enamel adjacent to brackets bonded with Vitremer were significantly lower than in teeth bonded with the composite, indicating that the resin-reinforced glass-ionomers significantly reduced caries lesion development in vivo. CLSM images show a severe cariogenic challenge around orthodontic brackets and support TMR measurements.

Bicuspid↗
PubMed1998

The electrical resistance of enamel-dentine cylinders. Influence of NaCl content in storage solutions.

OBJECTIVES: To investigate the influence of different electrolyte concentrations on the electrical resistance of sound human enamel-dentine cylinders in vitro. METHODS: Forty cylinders of 3-mm diameter and 2-mm length were drilled from 40 extracted caries-free third molar teeth. For ease of handling the samples were fixed in Perspex discs by means of a cyanoacrylate-adhesive. An a.c. source (frequency 500 Hz, amplitude 1 microA) with a high internal resistance was applied. Only Ohm's resistance was measured. The resistance measurements on the samples were made after storage in distilled water, 0.16 mM NaCl, 1.6 mM NaCl and 16 mM NaCl and 160 mM NaCl for 24 h. RESULTS: The mean resistance values were 2026 +/- 152, 1835 +/- 178, 1605 +/- 364, 483 +/- 265 and 60 +/- 33 k omega, respectively. All values were statistically significantly different (Wilcoxon test; P < 0.0001). CONCLUSION: It is concluded that the choice of electrolyte solution influences the resistance values of the enamel-dentine samples. This effect should be taken into account when measuring electrical resistances in vivo and in vitro.

Cyanoacrylates↗
PubMed1998

Influence of nail varnish on the remineralization of enamel single sections assessed by microradiography and confocal laser scanning microscopy.

Single-section techniques are attractive in enamel de- and remineralization investigations because they allow longitudinal studies in which mineral changes can be assessed by microradiography (TMR). Nail varnish (NV) is in general applied to coat the cut thin-section sides. The aims of this study were to investigate: (1) NV penetration depth in cut surfaces of demineralized enamel, (2) the influence of NV on cut surfaces of demineralized enamel on TMR, (3) the influence of NV penetration on a following remineralization. Cut surfaces of thin sections of demineralized enamel were NV coated; the NV was peeled off and the penetration depth assessed by confocal laser scanning microscopy. The NV penetration was 18+/-5 micrometer (mean+/-SD) in demineralized enamel. To evaluate the possible influence of NV on TMR, cut surfaces of thin sections of demineralized enamel were coated (twice) and microradiographed before and after nail varnishing. The NV effect (total effect of penetrated and surface NV) on the main parameters of TMR, Ld and DeltaZ, was less than 5% of the mean values. In the remineralization experiment (remineralization with 1.5 mM Ca2+, 0.9 mM phosphate, pH 7, 1 ppm F for 1 and 2 weeks), lesions in bulk samples, lesions in thin sections with NV-coated cut surfaces and lesions in thin sections in a PMMA (polymethylmethacrylate) holder were compared. (1) The remineralization of bulk samples and of NV-coated thin sections is different in one aspect. The amounts of mineral deposited in the lesions expressed as DeltaZ are comparable after 1 week. But because the NV penetrates part of the lesion outside, there was an Ld difference. The lesion depth difference between bulk lesions and NV-coated lesions in thin sections was statistically significant and was about 19% less in NV-coated lesions after 1 week; after 2 weeks of remineralization there was no difference in Ld between bulk- and NV-coated lesions any more. (2) There was no difference in remineralization efficacy between lesions in bulk samples and lesions in thin sections in the PMMA holder.

Adolescent↗
PubMed1998

Effect of toothpicks with and without fluoride on De- and remineralization of enamel and dentine in situ.

The aim of this investigation was to study the effect of the interproximal use of fluoride (F)-impregnated and non-impregnated birch toothpicks on the degree of de- and remineralization of enamel and dentine in situ. Ten volunteers with complete dentures in the upper jaw participated. Each subject had four specimens: (1) sound enamel, (2) demineralized enamel, (3) sound dentine and (4) demineralized dentine; placed pairwise at two approximal sites (15/16 and 25/26) of the maxillary prosthesis. The study involved three test periods (A, B and C), each lasting 4 weeks. In A, the subjects used F toothpicks (impregnated in 4% NaF) and, in B, nonimpregnated toothpicks 3 times daily. During period C, no toothpicks were used. Dentifrice or other F-containing products were not allowed during the 4-week periods. Transversal microradiography was used to determine lesion depth (ld) and mineral loss (DeltaZ). The results revealed that all the sound samples lost mineral during the three experimental periods; DeltaZ for both enamel and dentine was less for A and B compared with C (p<0.01) and less for A compared with B and C for dentine (p<0.05, p<0.01). The demineralized samples also lost mineral, apart from dentine, during periods A and B, i.e. when F-impregnated and non-impregnated toothpicks were used; ld for enamel and DeltaZ for dentine were less for A compared with C (p<0.05). Four weeks' use of toothpicks, especially F-impregnated toothpicks, thus reduces the demineralization of enamel and dentine at approximal sites in situ.

Aged↗
PubMed1997

Persistence or reappearance of nonmotile sperm after vasectomy: does it have clinical consequences?

OBJECTIVE: To determine the percentage of patients with nonmotile sperm 12 weeks after vasectomy, to estimate the time needed for eventual azoospermia in these patients, and to record the percentage of patients with recurrence of nonmotile sperm after initial azoospermia after vasectomy. DESIGN: A review of the semen analysis of vasectomies performed in a 2-year period. Semen analysis in a group of volunteers from 4 months until 24 months after vasectomy. SETTING: Vasectomies performed in an outpatient department of the University Hospital of Maastricht. PATIENT(S): Men referred by the general practitioner for a vasectomy. INTERVENTION(S): Vasectomy. MAIN OUTCOME MEASURE(S): Amount and motility of sperm in postvasectomy semen samples. RESULT(S): Nonmotile sperm was found in 33% of the patients 12 weeks after vasectomy. The mean time to azoospermia was 6.36 months. Nonmotile sperm after initial azoospermia was found in 5 of 65 patients. CONCLUSION(S): Azoospermia as a criterion for sterility leads to unnecessary prolonged semen analysis in a large percentage of the vasectomized patients. Reappearance of nonmotile sperm was found in an unexpectedly high percentage.

Adult↗
PubMed1997

Fluoride level in saliva after bonding orthodontic brackets with a fluoride containing adhesive.

The fluoride level in saliva is considered an important parameter in caries prevention. Elevation of the salivary fluoride level by a fluoride-releasing orthodontic bonding adhesive would most likely be beneficial in the prevention of enamel caries. In this study, the fluoride level in saliva was measured after bonding brackets with a visible light-curing adhesive containing fluoride (12.4 wt% total F). The fluoride released from the adhesive has been shown in a previous study to inhibit demineralization adjacent to orthodontic brackets in vivo. Twenty-four patients each had 20 brackets bonded and saliva samples taken before bonding (t = 0) and after 1, 3, and 6 months. The participants were requested to brush daily with a fluoride toothpaste during the study period. The saliva fluoride analysis was done with the microdiffusion method. The analysis of the saliva showed fluoride levels (+/- SD) of 0.011 +/- 0.007, 0.011 +/- 0.009, 0.0011 +/- 0.007, and 0.012 +/- 0.008 ppm at t = 0, 1, 3, and 6 months, respectively. There was no significant difference at the 5% level. The study indicated indirectly that the caries inhibiting effect of the orthodontic adhesive shown previously was most likely due to a localized fluoridation of the cariogenic environment rather than to an elevation of the fluoride level in saliva.

Adhesives↗