Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 42
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Reprod Fertil Dev ; 33(4): 291-304, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33573714

ABSTRACT

Trials to improve oocyte developmental competence under metabolic stress by using antioxidants may start before or after oocyte maturation. In the present conceptual study, we aimed to identify the most efficient timing of antioxidant application in relation to a metabolic insult using a bovine invitro embryo production model. Pathophysiological concentrations of palmitic acid (PA) were used to induce metabolic stress during oocyte maturation or embryo development. Trolox (TR; antioxidant) treatment prior to, during or after the PA insult was tested to evaluate the protective, neutralising and rescuing capacity of TR respectively. Changes in embryo developmental competence, mitochondrial activity, reactive oxygen species (ROS) concentrations, blastocyst cell allocation and apoptosis and cell stress-related gene expression were monitored. The improvement in developmental capacity was most obvious when oocytes were preloaded with TR before the PA insult. This protective effect could be explained by the observed combination of increased mitochondrial activity with reduced ROS production. This resulted in blastocysts with normal cell counts and apoptosis, as well as increased nuclear factor erythroid 2-related factor 2 (NRF2) expression (a marker for redox regulatory processes) and normalised the expression of the mitochondrial transcription factor A (TFAM), a marker of mitochondrial biogenesis. These results indicate that 'pretreatment' of oocytes with antioxidants produces embryos that seem to be more resilient to a metabolic stress insult.


Subject(s)
Antioxidants/pharmacology , Blastocyst/drug effects , Chromans/pharmacology , Oocytes/drug effects , Oxidative Stress/drug effects , Reactive Oxygen Species/metabolism , Animals , Apoptosis/drug effects , Blastocyst/metabolism , Blastocyst/pathology , Cattle , Cells, Cultured , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Embryo Culture Techniques , Female , Gene Expression Regulation, Developmental , In Vitro Oocyte Maturation Techniques , Mitochondria/drug effects , Mitochondria/metabolism , Mitochondria/pathology , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , Oocytes/metabolism , Oocytes/pathology , Palmitic Acid/toxicity , Transcription Factors/genetics , Transcription Factors/metabolism
2.
J Electrocardiol ; 63: 75-82, 2020.
Article in English | MEDLINE | ID: mdl-33142185

ABSTRACT

BACKGROUND: Electrocardiograph-generated measurements of PR, QRS, and QT intervals are generally thought to be more precise than manual measurements on paper records. However, the performance of different programs has not been well compared. METHODS: Routinely obtained digital electrocardiograms (ECGs), including over 500 pediatric ECGs, were used to create over 2000 10 s analog ECGs that were replayed through seven commercially available electrocardiographs. The measurements for PR interval, QRS duration, and QT interval made by each program were extracted and compared against each other (using the median of the programs after correction for program bias) and the population mean values. RESULTS: Small but significant systematic biases were seen between programs. The smallest and largest variation from the population mean differed by 4.7 ms for PR intervals, 5.8 ms for QRS duration, and 12.4 ms for QT intervals. In pairwise comparison programs showed similar accuracy for most ECGs, with the average absolute errors at the 75th percentile for PR intervals being 4-6 ms from the median, QRS duration 4-8 ms, and QT interval 6-10 ms. However, substantial differences were present in the numbers and extent of large, clinically significant errors (e.g at the 98th percentile), for which programs differed by a factor of two for absolute errors, as well as differences in the mix of overestimations and underestimations. CONCLUSIONS: When reading digital ECGs, users should be aware that small systematic differences exist between programs and that there may be large clinically important errors in difficult cases.


Subject(s)
Electrocardiography , Child , Humans
3.
J Electrocardiol ; 58: 143-149, 2020.
Article in English | MEDLINE | ID: mdl-31884310

ABSTRACT

BACKGROUND: No direct comparison of current electrocardiogram (ECG) interpretation programs exists. OBJECTIVE: Assess the accuracy of ECG interpretation programs in detecting abnormal rhythms and flagging for priority review records with alterations secondary to acute coronary syndrome (ACS). METHODS: More than 2,000 digital ECGs from hospitals and databases in Europe, USA, and Australia, were obtained from consecutive adult and pediatric patients and converted to 10 s analog samples that were replayed on seven electrocardiographs and classified by the manufacturers' interpretation programs. We assessed ability to distinguish sinus rhythm from non-sinus rhythm, identify atrial fibrillation/flutter and other abnormal rhythms, and accuracy in flagging results for priority review. If all seven programs' interpretation statements did not agree, cases were reviewed by experienced cardiologists. RESULTS: All programs could distinguish well between sinus and non-sinus rhythms and could identify atrial fibrillation/flutter or other abnormal rhythms. However, false-positive rates varied from 2.1% to 5.5% for non-sinus rhythm, from 0.7% to 4.4% for atrial fibrillation/flutter, and from 1.5% to 3.0% for other abnormal rhythms. False-negative rates varied from 12.0% to 7.5%, 9.9% to 2.7%, and 55.9% to 30.5%, respectively. Flagging of ACS varied by a factor of 2.5 between programs. Physicians flagged more ECGs for prompt review, but also showed variance of around a factor of 2. False-negative values differed between programs by a factor of 2 but was high for all (>50%). Agreement between programs and majority reviewer decisions was 46-62%. CONCLUSIONS: Automatic interpretations of rhythms and ACS differ between programs. Healthcare institutions should not rely on ECG software "critical result" flags alone to decide the ACS workflow.


Subject(s)
Atrial Fibrillation , Atrial Flutter , Adult , Australia , Child , Electrocardiography , Europe , Humans
4.
Reprod Fertil Dev ; 29(11): 2284-2300, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28390473

ABSTRACT

Lipolytic metabolic conditions are traditionally associated with elevated non-esterified fatty acid (NEFA) concentrations, but may also be accompanied by hyperglycaemia in obesity or by hypoglycaemia during a negative energy balance status. Elevated NEFA concentrations disrupt oocyte and embryo development and quality, but little is known about whether the effects of lipolytic conditions on oocyte developmental competence are modulated by glucose availability. To answer this, bovine cumulus-oocyte complexes (COCs) were matured under different conditions: physiological NEFA (72µM) and normal glucose (5.5mM), pathophysiologically high NEFA (420µM) and normal glucose, high NEFA and high glucose (9.9mM), high NEFA and low glucose (2.8mM). Developmental potential, cumulus expansion and metabolism of COCs exposed to high NEFA and low glucose were affected to a greater extent compared with COCs matured under high NEFA and high glucose conditions. High NEFA and high glucose conditions caused a moderate increase in oocyte reactive oxygen species compared with their high NEFA and low glucose or control counterparts. Blastocyst metabolism and the transcriptome of metabolic and oxidative stress-related genes were not affected. However, both lipolytic conditions associated with hyper- or hypoglycaemia led to surviving embryos of reduced quality with regards to apoptosis and blastomere allocation.


Subject(s)
Embryonic Development/drug effects , Energy Metabolism/drug effects , Glucose/administration & dosage , Lipolysis/drug effects , Oocytes/drug effects , Oxidative Stress/drug effects , Animals , Cattle , Cumulus Cells/drug effects , Cumulus Cells/metabolism , Dose-Response Relationship, Drug , Embryonic Development/physiology , Female , In Vitro Oocyte Maturation Techniques , Lipolysis/physiology , Oocytes/metabolism , Reactive Oxygen Species/metabolism
5.
J Dairy Sci ; 99(7): 5808-5819, 2016 Jul.
Article in English | MEDLINE | ID: mdl-27157583

ABSTRACT

Maternal metabolic pressure due to a cow's negative energy balance (NEB) has a negative effect on oocyte quality as a result of increased oxidative stress. In this study, we hypothesized that a NEB status may negatively affect the availability of ß-carotene (bC, an antioxidant) in the micro-environment of the oocyte or follicular fluid (FF) and that daily bC supplementation can increase bC availability. We aimed to (1) determine the effect of a nutritionally induced NEB on bC concentrations in serum and FF as well as on the presence of bC metabolites, oxidative stress levels, and follicular growth in a nonlactating dairy cow model, and (2) investigate how this effect could be altered by dietary bC supplementation. Six multiparous nonlactating Holstein Friesian cows were subjected to 4 consecutive dietary treatments, 28 d each: (1) 1.2 × maintenance (M) or positive energy balance (PEB) without bC supplement (PEB-bC), (2) 1.2 × M with daily supplement of 2,000mg of bC comparable to the level of bC intake at grazing (PEB+bC), (3) 0.6 × M with 2,000mg of bC (NEB+bC), and (4) 0.6 × M (NEB-bC). At the end of each treatment, estrous cycles were synchronized and blood and FF of the largest follicle were sampled and analyzed for bC, retinol, α-tocopherol, free fatty acids, estradiol, and progesterone. Serum cholesterol, triglycerides, urea, insulin growth factor 1, growth hormone, total antioxidant status (TAS), and red blood cell glutathione (GSH) concentrations were determined as well. All cows lost body weight during both energy restriction periods and showed increased serum free fatty acid concentrations, illustrating a NEB. A dietary induced NEB reduced FF bC, but not plasma bC or plasma and FF retinol concentrations. However, bC and retinol concentrations drastically increased in both fluid compartments after bC supplementation. Follicular diameter was increased in supplemented PEB cows. Energy restriction reduced the TAS and red blood cell GSH, whereas daily bC supplementation could restore GSH concentrations, but not the TAS, to levels present in healthy PEB cows. In conclusion, daily bC supplementation can substantially improve bC and retinol availability in the oocyte's micro-environment, irrespective of the energy balance, which may affect follicular development and oocyte quality in the presence of maternal metabolic stress. This knowledge can be of importance to optimize nutritional strategies in the dairy industry to feed for optimal oocyte quality and fertility.


Subject(s)
Follicular Fluid , beta Carotene/metabolism , Animals , Cattle , Energy Metabolism , Fatty Acids, Nonesterified/blood , Female , Lactation/metabolism , Ovarian Follicle/metabolism
6.
Br J Anaesth ; 115(5): 743-51, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25935840

ABSTRACT

BACKGROUND: This study aimed to investigate whether reversal of rocuronium-induced neuromuscular blockade with sugammadex reduced the incidence of residual blockade and facilitated operating room discharge readiness. METHODS: Adult patients undergoing abdominal surgery received rocuronium, followed by randomized allocation to sugammadex (2 or 4 mg kg(-1)) or usual care (neostigmine/glycopyrrolate, dosing per usual care practice) for reversal of neuromuscular blockade. Timing of reversal agent administration was based on the providers' clinical judgement. Primary endpoint was the presence of residual neuromuscular blockade at PACU admission, defined as a train-of-four (TOF) ratio <0.9, using TOF-Watch® SX. Key secondary endpoint was time between reversal agent administration and operating room discharge-readiness; analysed with analysis of covariance. RESULTS: Of 154 patients randomized, 150 had a TOF value measured at PACU entry. Zero out of 74 sugammadex patients and 33 out of 76 (43.4%) usual care patients had TOF-Watch SX-assessed residual neuromuscular blockade at PACU admission (odds ratio 0.0, 95% CI [0-0.06], P<0.0001). Of these 33 usual care patients, 2 also had clinical evidence of partial paralysis. Time between reversal agent administration and operating room discharge-readiness was shorter for sugammadex vs usual care (14.7 vs. 18.6 min respectively; P=0.02). CONCLUSIONS: After abdominal surgery, sugammadex reversal eliminated residual neuromuscular blockade in the PACU, and shortened the time from start of study medication administration to the time the patient was ready for discharge from the operating room. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov:NCT01479764.


Subject(s)
Androstanols/antagonists & inhibitors , Delayed Emergence from Anesthesia/prevention & control , Neuromuscular Junction/drug effects , Neuromuscular Nondepolarizing Agents/antagonists & inhibitors , gamma-Cyclodextrins/pharmacology , Abdomen/surgery , Adult , Aged , Anesthesia Recovery Period , Anesthesia, General/methods , Dose-Response Relationship, Drug , Double-Blind Method , Drug Combinations , Female , Glycopyrrolate/pharmacology , Humans , Male , Middle Aged , Neostigmine/pharmacology , Neuromuscular Blockade , Neuromuscular Junction/physiopathology , Postoperative Care/methods , Rocuronium , Sugammadex , gamma-Cyclodextrins/administration & dosage , gamma-Cyclodextrins/adverse effects
7.
Reprod Domest Anim ; 49(3): 353-61, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24697981

ABSTRACT

In many countries, fat supplementation in the diet has become common in the dairy industry. There are several ideas as to how dietary fat could influence reproductive performance. Saturated fatty acids, such as palm oil, can increase milk yield but may aggravate negative energy balance and thus may impair fertility when fed during the first week post-partum. However, priming the lipid oxidation in the liver by feeding saturated fats during the dry period has recently been shown to be a potentially promising strategy to mitigate fat mobilization and liver accumulation post-partum. Furthermore, polyunsaturated fats (omega-3 fatty acids and conjugated linoleic acids) are fed to reduce the 'de novo' fat synthesis in the udder and thus the milk fat content, which may be of modest benefit for overall energy balance. Furthermore, omega-6 and omega-3 polyunsaturated fatty acids are reported to alter follicular growth, steroid synthesis and prostaglandin metabolism in the ovary and endometrium, respectively. Omega-6 fatty acids are believed to have pro-inflammatory and thus PGF2α-stimulating properties rendering them extra value as 'nutraceutical' early post-partum, while omega-3 fatty acids can weaken this inflammatory potency, leading to a higher chance of survival of the embryo when supplemented during the periconceptual period. Unfortunately, research results rarely provide a consensus in this perspective. The consequences of these fat-feeding strategies on oocyte and embryo quality remain an intriguing issue for debate. Fat feeding may alter the microenvironment of the growing and maturing oocyte of the early and older embryo and thus may affect reproductive outcome. We recently reported that dietary-induced hyperlipidaemic conditions can be harmful for embryo development and metabolism. However, to date, research results remain somewhat conflicting most probably due to differences in fat sources used, in diet and duration of supplementation and in experimental set-up in general.


Subject(s)
Cattle/physiology , Dairying/trends , Diet/veterinary , Dietary Fats/administration & dosage , Embryo, Mammalian/physiology , Oocytes/physiology , Reproduction/physiology , Animal Nutritional Physiological Phenomena , Animals , Cattle/embryology , Dairying/methods , Embryo, Mammalian/chemistry , Energy Metabolism , Female , Lipids/analysis , Ovarian Follicle/growth & development , Ovary/physiology , Uterus/physiology
8.
Tijdschr Psychiatr ; 51(11): 847-52, 2009.
Article in Dutch | MEDLINE | ID: mdl-19904710

ABSTRACT

A 51-year-old woman suffering an epileptic seizure came to the emergency unit. A ct scan showed a mass lesion in the right frontal lobe. The psychiatric examination indicated a frontal syndrome with severe cognitive impairment. A stereotactical biopsy was carried out. Histopathology produced an unusual diagnosis, namely an intracerebral amyloidoma. By reviewing the literature on intracerebral amyloidoma we were able to compare the psychiatric symptoms of published cases with those of this case.


Subject(s)
Amyloidosis/diagnosis , Brain Neoplasms/diagnosis , Cerebral Ventricles/pathology , Frontal Lobe/pathology , Biopsy , Diagnosis, Differential , Female , Humans , Middle Aged , Tomography, X-Ray Computed
9.
Neurotox Res ; 30(3): 285-94, 2016 10.
Article in English | MEDLINE | ID: mdl-27342132

ABSTRACT

Schizophrenia has a clear sexual dimorphism in age of onset and progression. The underlying mechanisms of this dimorphism are not known, but may be found in the interactions of sex hormones with the tryptophan catabolising kynurenine pathway. Schizophrenia is associated with general inflammation and disruption of glutamatergic and dopaminergic signalling. Metabolites of the kynurenine pathway have been shown to be immunomodulatory and have effects on glutamatergic and dopaminergic signalling. This review discusses the currently available literature on sex hormones and their effect on the kynurenine pathway in the context of the glutamatergic, dopaminergic and immunological features of schizophrenia.


Subject(s)
Kynurenine/metabolism , Schizophrenia/immunology , Sex Characteristics , Animals , Humans , Neuroimmunomodulation/physiology
10.
Int J Tryptophan Res ; 9: 89-93, 2016.
Article in English | MEDLINE | ID: mdl-27980422

ABSTRACT

We have previously demonstrated that the kynurenine pathway (KP), the major biochemical pathway for tryptophan metabolism, is dysregulated in many inflammatory disorders that are often associated with sexual dimorphisms. We aimed to identify a potential functional interaction between the KP and gonadal hormones. We have treated primary human macrophages with progesterone in the presence and absence of inflammatory cytokine interferon-gamma (interferon-γ) that is known to be a potent inducer of regulating the KP enzyme. We found that progesterone attenuates interferon-γ-induced KP activity, decreases the levels of the excitotoxin quinolinic acid, and increases the neuroprotective kynurenic acid levels. We also showed that progesterone was able to reduce the inflammatory marker neopterin. These results may shed light on the gender disparity in response to inflammation.

11.
Trends Pharmacol Sci ; 12(10): 379-83, 1991 Oct.
Article in English | MEDLINE | ID: mdl-1763431

ABSTRACT

Pharmacology is the study of the interaction of drugs with living organisms, especially humans. The body is a very complicated system, which suggests that the 'effect' induced by a drug is not a single entity but a change in several variables at the same time, all of which are interrelated in a nonlinear fashion. Research on nonlinear systems in other fields of science--commonly known as chaos theory--may therefore be of use in understanding pharmacology, as explained here by J. M. van Rossum and J. E. G. M. de Bie. They argue that in the study of drug effects, several variables should be measured simultaneously. Many pharmacologists prefer to construct an illusion of reality, studying just one of the essential variables and averaging data in a population of subjects, thus losing the opportunity to understand what a drug really does to a patient.


Subject(s)
Pharmacology , Animals , Humans
12.
Int J Nurs Stud ; 42(6): 637-48, 2005 Aug.
Article in English | MEDLINE | ID: mdl-15970292

ABSTRACT

Occurrence of problems with, refusals of orders and contemplated refusals of orders for risky procedures by nurses in Dutch hospitals and views on the safety of performance was studied using postal questionnaires (600 physicians and 3200 nurses, response 60--71%). Of the respondents, 11--30% experienced problems with and (contemplated) refusals of orders for risky procedures in the previous 12 months. Gynaecologists and internists most frequently mentioned problems concerning the practical performance of the procedure (44% and 30%, respectively). The reason for a problem or a contemplated refusal most frequently given by nurses was that they disagreed with the medication policy (34% and 35%, respectively). The reason for a refusal most frequently given by the gynaecologists, internists, and nurses was that the nurses themselves were of the opinion that they did not have the necessary authorisation (95%, 67%, and 62%, respectively). With regard to certain procedures, the views of professionals are more strict than the current legal regulations.


Subject(s)
Attitude of Health Personnel , Medical Staff, Hospital/psychology , Nursing Staff, Hospital/psychology , Personnel Delegation , Refusal to Treat , Risk-Taking , Clinical Competence/legislation & jurisprudence , Clinical Competence/standards , Conflict, Psychological , Female , Gynecology , Humans , Internal Medicine , Male , Medical Staff, Hospital/organization & administration , Netherlands , Nurse's Role/psychology , Nursing Methodology Research , Nursing Staff, Hospital/education , Nursing Staff, Hospital/organization & administration , Organizational Policy , Personnel Delegation/organization & administration , Physician's Role/psychology , Physician-Nurse Relations , Professional Autonomy , Refusal to Treat/legislation & jurisprudence , Safety Management , Self Efficacy , Surveys and Questionnaires
13.
Int J Nurs Stud ; 42(7): 759-71, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16084924

ABSTRACT

Occurrence of problems with, refusals of orders and contemplated refusals of orders for risky procedures by nurses in Dutch hospitals and views on the safety of performance was studied using postal questionnaires (600 physicians and 3200 nurses, response 60-71%). Of the respondents, 11-30% experienced problems with and (contemplated) refusals of orders for risky procedures in the previous 12 months. Gynaecologists and internists most frequently mentioned problems concerning the practical performance of the procedure (44% and 30%, respectively). The reason for a problem or a contemplated refusal most frequently given by nurses was that they disagreed with the medication policy (34% and 35%, respectively). The reason for a refusal most frequently given by the gynaecologists, internists and nurses was that the nurses themselves were of the opinion that they did not have the necessary authorisation (95%, 67%, and 62%, respectively). With regard to certain procedures, the views of professionals are more strict than the current legal regulations.


Subject(s)
Attitude of Health Personnel , Delegation, Professional , Nursing Staff, Hospital/standards , Physician-Nurse Relations , Risk Management , Gynecology , Humans , Internal Medicine , Netherlands , Nurse's Role , Risk Management/legislation & jurisprudence
15.
Clin Pharmacokinet ; 17(1): 27-44, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2663303

ABSTRACT

Pharmacokinetics is in essence the study of the input/output relationships of the (human) body, which is considered as a system characterised by a density function of residence times. The input is the dosage rate, and the output is the concentration in the blood. The body transport function is first derived in a model-independent fashion, assuming linear kinetics. It is subsequently defined on the basis of a positive feedback loop of transport through the pulmonary and systemic circulation. Thus, the residence times distribution is based on transit times distributions and recirculation. The relevant dynamic systems parameters are cardiac output, extraction ratio, clearance, volume of distribution, mean transit time and mean residence time. In the case of drug absorption, mean absorption time and bioavailability are also important. In this review, the systems approach in pharmacokinetics is illustrated by clinical and computational experiments.


Subject(s)
Pharmacokinetics , Systems Analysis , Biological Transport , Humans , Methods , Statistics as Topic , Time Factors
16.
Br J Pharmacol ; 119(7): 1484-90, 1996 Dec.
Article in English | MEDLINE | ID: mdl-8968559

ABSTRACT

1. Mice were sensitized by 7 intraperitoneal injections of ovalbumin without adjuvant (10 micrograms in 0.5 ml of sterile saline) on alternate days and after 3 weeks exposed to either ovalbumin (2 mg ml-1 in sterile saline) or saline aerosol for 5 min on 8 consecutive days. One day before the first challenge, animals were injected intraperitoneally on a daily basis with vehicle (0.25 ml sterile saline), dexamethasone (0.5 mg kg-1) or metyrapone (30 mg kg-1). 2. In vehicle-treated ovalbumin-sensitized animals ovalbumin challenge induced a significant increase of airway responsiveness to metacholine both in vitro (27%, P < 0.05) and in vivo (40%, P < 0.05) compared to saline-challenged mice. Virtually no eosinophils could be detected after saline challenge, whereas the numbers of eosinophils were significantly increased (P < 0.01) at both 3 and 24 h after the last ovalbumin challenge (5.48 +/- 3.8 x 10(3) and 9.13 +/- 1.7 x 10(3) cells, respectively). Furthermore, a significant increase in ovalbumin-specific immunoglobulin E level (583 +/- 103 units ml-1, P < 0.05) was observed after ovalbumin challenge compared to saline challenge (201 +/- 38 units ml-1). 3. Plasma corticosterone level was significantly reduced (-92%, P < 0.001) after treatment with metyrapone. Treatment with metyrapone significantly increased eosinophil infiltration (17.4 +/- 9.93 x 10(3) and 18.7 +/- 2.57 x 10(3) cells, P < 0.05 at 3 h and 24 h, respectively) and potentiated airway hyperresponsiveness to methacholine compared to vehicle-treated ovalbumin-challenged animals. Dexamethasone inhibited both in vitro and in vivo hyperresponsiveness as well as antigen-induced infiltration of eosinophils (0, P < 0.05 and 0.7 +/- 0.33 x 10(3) cells, P < 0.05 at 3 h and 24 h, respectively). Metyrapone as well as dexamethasone did not affect the increase in ovalbumin-specific immunoglobulin E levels after ovalbumin challenge (565 +/- 70 units/ml-1; P < 0.05; 552 +/- 48 units ml-1, P < 0.05 respectively). 4. From these data it can be concluded that exogenously applied corticosteroids can inhibit eosinophil infiltration as well as airway hyperresponsiveness. Vise versa, endogenously produced corticosteroids play a down-regulating role on the induction of both eosinophil infiltration and airway hyperresponsiveness.


Subject(s)
Anti-Inflammatory Agents/pharmacology , Bronchial Hyperreactivity/physiopathology , Corticosterone/physiology , Dexamethasone/pharmacology , Eosinophilia/blood , Animals , Asthma/pathology , Asthma/physiopathology , Bronchial Hyperreactivity/pathology , Bronchoalveolar Lavage Fluid/cytology , Bronchodilator Agents/pharmacology , Corticosterone/blood , Immunoglobulin E/biosynthesis , In Vitro Techniques , Male , Methacholine Chloride/pharmacology , Metyrapone/pharmacology , Mice , Mice, Inbred BALB C , Ovalbumin/immunology
17.
Br J Pharmacol ; 124(5): 857-64, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9692769

ABSTRACT

1. Since both histamine and 5-hydroxytryptamine (5-HT) can be released by murine mast cells, we investigated the possible role of these autacoids on airway hyperresponsiveness (AHR), eosinophil infiltration and serum-IgE levels in a murine model of allergic asthma. 2. Ovalbumin-sensitized mice were exposed to either ovalbumin (2 mg ml(-1)) or saline aerosols on 8 consecutive days. Starting one day before the challenge, animals were injected i.p. twice a day with a 5-HT-type 1 (5-HT1) or type 2 (5-HT2) receptor antagonist (methiotepine, 1.25 or 2.0 mg kg(-1) and ketanserin, 12 mg kg(-1), respectively) or a histamine-type 1 (H1) or type 2 (H2) receptor antagonist (mepyramine, 12 or 20 mg kg(-1) and cimetidine, 10 or 25 mg kg(-1), respectively). Furthermore, animals were injected with a combination of cimetidine and ketanserin or with an alpha-adrenoceptor antagonist (phentolamine, 5 mg kg(-1)). 3. In vehicle-treated ovalbumin-challenged animals airway responsiveness to intravenous injections of methacholine in vivo was significantly (9 fold increase, P<0.01) increased when compared to vehicle-treated saline-challenged animals. Furthermore, ovalbumin challenge of vehicle-treated animals induced a significant increase in both eosinophil numbers in bronchoalveolar lavage (BAL) fluid (0+/-0, vehicle/saline and 15.0+/-5.9 x 10(4) cells vehicle/ovalbumin, P<0.05) and ovalbumin-specific IgE levels in serum (157+/-69 and 617+/-171 units ml(-1), respectively, P<0.05) compared to saline-challenged mice. Virtually no eosinophils could be detected in saline-challenged animals after all different treatments. 4. Treatment with ketanserin or cimetidine resulted in a partial but significant decrease of the ovalbumin-induced AHR compared to ovalbumin-challenged controls (P<0.05) and reduced eosinophil infiltration after ovalbumin challenge by 60% and 58%, respectively. The combination of cimetidine and ketanserin almost completely abolished AHR whereas eosinophilia was decreased by 49%. No effects of these antagonists were observed on IL-16 levels in BAL fluid or on serum antigen-specific IgE levels. Treatment with either the H1-receptor, the 5-HT1-receptor or the alpha-adrenoceptor antagonist, did not decrease the observed ovalbumin-induced airway responsiveness or eosinophilia in vehicle-treated animals. Higher doses of either methiotepine (2.0 mg kg(-1)) or mepyramine (20 mg kg(-1)) did decrease ovalbumin-induced eosinophil infiltration (by 67%, P<0.05 and 73%, respectively), whereas no effects of these antagonists were observed on ovalbumin-specific IgE levels in serum. 5. From these data it can be concluded that both histamine and 5-HT play a role in antigen-induced AHR and eosinophilia in the mouse.


Subject(s)
Asthma/pathology , Bronchial Hyperreactivity/pathology , Eosinophilia/pathology , Histamine Antagonists/pharmacology , Serotonin Antagonists/pharmacology , Airway Resistance/drug effects , Animals , Asthma/blood , Asthma/physiopathology , Bronchial Hyperreactivity/blood , Bronchial Hyperreactivity/physiopathology , Bronchoalveolar Lavage Fluid/chemistry , Bronchoalveolar Lavage Fluid/cytology , Bronchoconstrictor Agents/pharmacology , Eosinophilia/blood , Immunoglobulin E/blood , Immunoglobulin E/immunology , Male , Methacholine Chloride/pharmacology , Mice , Mice, Inbred BALB C , Ovalbumin/immunology , Succinimides/chemistry , Succinimides/metabolism
18.
J Clin Psychiatry ; 62 Suppl 22: 30-3, 2001.
Article in English | MEDLINE | ID: mdl-11599645

ABSTRACT

BACKGROUND: Treatment guidelines recommend antidepressant treatment be continued for at least 6 months to ensure maximal improvement and to prevent relapse. Naturalistic studies show that the average length of treatment is shorter than 6 months and that dropout rates are high. Factors leading patients to discontinuation of therapy are not well understood. This study investigates when and why patients stop treatment and whether they inform their doctors. METHOD: Patients (N = 272) receiving antidepressant therapy due to an episode of major depressive disorder (DSM-IV) were asked to complete an antidepressant compliance questionnaire. Patients were then telephoned monthly while they continued on antidepressant therapy, up to 6 months. During each call, patients were asked standard questions. RESULTS: By endpoint, 53% of patients had discontinued antidepressant treatment. The most common reason given was "feeling better." However, different dropout reasons were prevalent at different times after initiation of therapy. Overall, 24% of the patients did not inform their physician about stopping the antidepressant medication. The likelihood of patients' informing their physicians differed according to the patients' reasons for discontinuation and according to the patients' perceptions of their relationship with their physicians. CONCLUSION: These results provide new guidelines for improving compliance. Strategy should be adapted to the stage of treatment, as patients' reasons for discontinuation vary as treatment progresses. The attitude of the physician and the information provided by the physician significantly influence whether patients inform the physician when they discontinue antidepressant therapy.


Subject(s)
Antidepressive Agents/therapeutic use , Depressive Disorder/drug therapy , Patient Compliance , Primary Health Care/statistics & numerical data , Adult , Attitude of Health Personnel , Attitude to Health , Communication , Depressive Disorder/prevention & control , Female , Humans , Male , Patient Dropouts/psychology , Patient Dropouts/statistics & numerical data , Patient Selection , Physician-Patient Relations , Practice Guidelines as Topic , Probability , Research Design/standards , Secondary Prevention , Selection Bias , Surveys and Questionnaires , Survival Analysis , Telephone , Treatment Outcome
19.
J Clin Psychiatry ; 62 Suppl 22: 34-7, 2001.
Article in English | MEDLINE | ID: mdl-11599646

ABSTRACT

BACKGROUND: DSM-IV diagnosis of major depressive disorder includes a requirement that symptoms result in significant clinical distress or impairment. This criterion is difficult to assess and is often overlooked. This study examines the use of the Sheehan Disability Scale as a possible method of assessing impairment, as well as the relationship between functioning and discontinuation of antidepressant medication. METHOD: Patients (N = 272) receiving antidepressant therapy due to an episode of major depressive disorder were asked to complete an antidepressant compliance questionnaire. Patients were telephoned monthly while they continued on antidepressant therapy, up to 6 months. During each call, the Sheehan Disability Scale was administered. RESULTS: Of patients referred to this study, 94.8% met DSM-IV criteria of at least 5 symptoms of major depressive disorder. Most patients had initial scores ranging from 5 to 8 on all 3 Sheehan disability subscales (occupational, social, and family functioning); 72% of patients had at least moderate impairment (scores > or = 4) on all 3 subscales. After 8 weeks of treatment, 42% of patients had scores < 4 on all 3 subscales (recovery); after 24 weeks, 64% of patients had scores < 4 on all 3 subscales. Dropout risk in men was related to improvement in occupational, social, and family functioning, whereas dropout risk in women was related only to improvement in family functioning. CONCLUSION: The Sheehan Disability Scale can be valuable in assessing impairment and thus in correctly diagnosing major depressive disorder. We suggest that scores of 4 or more (moderate impairment) on all 3 subscales indicate sufficient impairment for a strict diagnosis of major depressive disorder. Functional symptoms continued to improve for up to 24 weeks on antidepressant therapy, suggesting 6 months or more of therapy is necessary for maximum functional improvement. Premature discontinuation of antidepressant therapy is more likely to occur in women who experience significant improvement in family functioning or men who experience significant improvement in any functional area.


Subject(s)
Antidepressive Agents/therapeutic use , Depressive Disorder/drug therapy , Patient Compliance , Primary Health Care/statistics & numerical data , Adult , Attitude of Health Personnel , Attitude to Health , Depressive Disorder/diagnosis , Disability Evaluation , Family Relations , Female , Follow-Up Studies , Humans , Male , Patient Dropouts/psychology , Patient Dropouts/statistics & numerical data , Psychiatric Status Rating Scales/statistics & numerical data , Severity of Illness Index , Sex Factors , Social Adjustment , Substance Withdrawal Syndrome/etiology , Substance Withdrawal Syndrome/psychology , Surveys and Questionnaires , Treatment Outcome
20.
Eur J Pharmacol ; 383(2): 189-96, 1999 Oct 27.
Article in English | MEDLINE | ID: mdl-10585533

ABSTRACT

In this study, we examined whether peptides based on the hydrophilic Cluster of Differentiation (CD) 4-binding part of the amino acid sequence of human interleukin-16 can block interleukin-16-induced chemotaxis of murine lymphocytes in vitro. Peptide 3 was capable of inhibiting interleukin-16-induced chemotaxis of murine splenocytes in vitro. Next, we compared the effects of intra-airway administration of peptide 3 with those of antibodies to interleukin-16 on antigen-induced features in a murine model of allergic asthma. Intra-airway administration of peptide 3 largely inhibited the development of antigen-induced airway hyperresponsiveness while airway eosinophilia was not affected. Similar effects were observed after intranasal application of antibodies to interleukin-16. These results indicate that treatment with peptide 3 causes the same effects as do antibodies to interleukin-16, possibly via the inhibition of interaction between interleukin-16 and its receptor CD4. Therefore, peptide 3 could be useful as a lead compound in attempting to limit airway hyperresponsiveness via binding to CD4.


Subject(s)
Anti-Asthmatic Agents/therapeutic use , Asthma/drug therapy , Interleukin-16/antagonists & inhibitors , Interleukin-16/pharmacology , Peptide Fragments/pharmacology , Administration, Intranasal , Airway Resistance/drug effects , Amino Acid Sequence , Animals , Anti-Asthmatic Agents/administration & dosage , Antibodies, Blocking/pharmacology , Bronchial Hyperreactivity/drug therapy , Bronchoalveolar Lavage Fluid/cytology , Cell Separation , Chemotaxis, Leukocyte/drug effects , Eosinophils/drug effects , Eosinophils/metabolism , In Vitro Techniques , Interleukin-16/administration & dosage , Methacholine Chloride/pharmacology , Mice , Mice, Inbred BALB C , Molecular Sequence Data , Muscarinic Agonists/pharmacology , Oligopeptides/pharmacology , Ovalbumin/immunology , Peptide Fragments/administration & dosage
SELECTION OF CITATIONS
SEARCH DETAIL