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1.
MAbs ; 15(1): 2254676, 2023.
Article in English | MEDLINE | ID: mdl-37698877

ABSTRACT

Prolactin (PRL) has recently been demonstrated to elicit female-selective nociceptor sensitization and increase pain-like behaviors in female animals. Here we report the discovery and characterization of first-in-class, humanized PRL neutralizing monoclonal antibodies (PRL mAbs). We obtained two potent and selective PRL mAbs, PL 200,031 and PL 200,039. PL 200,031 was engineered as human IgG1 whereas PL 200,039 was reformatted as human IgG4. Both mAbs have sub-nanomolar affinity for human PRL (hPRL) and produce concentration-dependent and complete inhibition of hPRL signaling at the hPRL receptor (hPRLR). These two PRL mAbs are selective for hPRL as they do not inhibit other hPRLR agonists such as human growth hormone or placental lactogen. They also cross-react with non-human primate PRL but not with rodent PRL. Further, both mAbs show long clearance half-lives after intravenous administration in FcRn-humanized mice. Consistent with their isotypes, these mAbs only differ in binding affinities to Fcγ receptors, as expected by design. Finally, PL 200,019, the murine parental mAb of PL 200,031 and PL 200,039, fully blocked stress-induced and PRL-dependent pain behaviors in female PRL-humanized mice, thereby providing in vivo preclinical proof-of-efficacy for PRL mAbs in mechanisms relevant to pain in females.


Subject(s)
Prolactin , Receptors, Prolactin , Female , Mice , Animals , Pregnancy , Prolactin/metabolism , Prolactin/pharmacology , Receptors, Prolactin/metabolism , Antibodies, Monoclonal , Placenta/metabolism , Protein Binding
2.
J Clin Endocrinol Metab ; 107(1): e328-e347, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34387319

ABSTRACT

CONTEXT: Recent evidence suggests that vasomotor symptoms (VMS) or hot flashes in the postmenopausal reproductive state and polycystic ovary syndrome (PCOS) in the premenopausal reproductive state emanate from the hyperactivity of Kiss1 neurons in the hypothalamic infundibular/arcuate nucleus (KNDy neurons). OBJECTIVE: We demonstrate in 2 murine models simulating menopause and PCOS that a peripherally restricted kappa receptor agonist (PRKA) inhibits hyperactive KNDy neurons (accessible from outside the blood-brain barrier) and impedes their downstream effects. DESIGN: Case/control. SETTING: Academic medical center. PARTICIPANTS: Mice. INTERVENTIONS: Administration of peripherally restricted kappa receptor agonists and frequent blood sampling to determine hormone release and body temperature. MAIN OUTCOME MEASURES: LH pulse parameters and body temperature. RESULTS: First, chronic administration of a PRKA to bilaterally ovariectomized mice with experimentally induced hyperactivity of KNDy neurons reduces the animals' elevated body temperature, mean plasma LH level, and mean peak LH per pulse. Second, chronic administration of a PRKA to a murine model of PCOS, having elevated plasma testosterone levels and irregular ovarian cycles, suppresses circulating levels of LH and testosterone and restores normal ovarian cyclicity. CONCLUSION: The inhibition of kisspeptin neuronal activity by activation of kappa receptors shows promise as a novel therapeutic approach to treat both VMS and PCOS in humans.


Subject(s)
Hot Flashes/drug therapy , Kisspeptins/antagonists & inhibitors , Menopause/metabolism , Polycystic Ovary Syndrome/drug therapy , Receptors, Opioid, kappa/agonists , Animals , Buprenorphine/administration & dosage , Disease Models, Animal , Female , Hot Flashes/blood , Hot Flashes/etiology , Humans , Kisspeptins/metabolism , Meloxicam/administration & dosage , Menopause/blood , Mice , Neurons/drug effects , Neurons/metabolism , Polycystic Ovary Syndrome/metabolism , Receptors, Opioid, kappa/metabolism , Vasomotor System/drug effects
3.
J Pharmacol Exp Ther ; 373(2): 193-203, 2020 05.
Article in English | MEDLINE | ID: mdl-32075870

ABSTRACT

Glucagon-like peptide-2 (GLP-2) agonists have therapeutic potential in clinical indications in which the integrity or absorptive function of the intestinal mucosa is compromised, such as in short bowel syndrome (SBS). Native hGLP-2, a 33-amino acid peptide secreted from the small intestine, contributes to nutritional absorption but has a very short half-life because of enzymatic cleavage and renal clearance and thus is of limited therapeutic value. The GLP-2 analog teduglutide (Revestive/Gattex; Shire Inc.) has been approved for use in SBS since 2012 but has a once-daily injection regimen. Pharmacokinetic (PK) and pharmacodynamic studies confirm that apraglutide, a novel GLP-2 analog, has very low clearance, long elimination half-life, and high plasma protein binding compared with GLP-2 analogs teduglutide and glepaglutide. Apraglutide and teduglutide retain potency and selectivity at the GLP-2 receptor comparable to native hGLP-2, whereas glepaglutide was less potent and less selective. In rat intravenous PK studies, hGLP-2, teduglutide, glepaglutide, and apraglutide had clearances of 25, 9.9, 2.8, and 0.27 ml/kg per minute, respectively, and elimination half-lives of 6.4, 19, 16, and 159 minutes, respectively. The unique PK profile of apraglutide administered via intravenous and subcutaneous routes was confirmed in monkey and minipig and translated into significantly greater in vivo pharmacodynamic activity, measured as small intestinal growth in rats. Apraglutide showed greater intestinotrophic activity than the other peptides when administered at less-frequent dosing intervals because of its prolonged half-life. We postulate that apraglutide offers several advantages over existing GLP-2 analogs and is an excellent candidate for the treatment of gastrointestinal diseases, such as SBS. SIGNIFICANCE STATEMENT: Apraglutide is a potent and selective GLP-2 agonist with an extremely low clearance and prolonged elimination half-life, which differentiates it from teduglutide (the only approved GLP-2 agonist). The enhanced pharmacokinetics of apraglutide will benefit patients by enabling a reduced dosing frequency and removing the need for daily injections.


Subject(s)
Glucagon-Like Peptide 2/agonists , Peptides/pharmacology , Short Bowel Syndrome/drug therapy , Animals , Glucagon-Like Peptide-2 Receptor/agonists , Glucagon-Like Peptide-2 Receptor/physiology , HEK293 Cells , Half-Life , Humans , Macaca fascicularis , Male , Peptides/pharmacokinetics , Peptides/therapeutic use , Rats , Rats, Sprague-Dawley , Swine , Swine, Miniature
4.
J Med Chem ; 62(10): 4991-5005, 2019 05 23.
Article in English | MEDLINE | ID: mdl-31022340

ABSTRACT

The vasopressin analogue desmopressin (desamino-d-arginine8 vasopressin, dDAVP, 1) is a potent vasopressin 2 (V2) receptor (V2R) agonist approved in many countries for the treatment of diabetes insipidus, primary nocturnal enuresis, nocturia, and coagulation disorders. Since 1 is primarily excreted via the kidneys, an age-related decline in kidney function leads to slower elimination, prolonged antidiuresis, and hyponatremia. In search of novel, potent, selective, and short-acting peptidic V2R agonists, we synthesized a series of C-terminally truncated analogues of [Val4]dDAVP, 2, modified in positions 2, 3, and 7 and/or at the disulfide bridge. The peptides were evaluated for in vitro potency at the human V2 receptor, selectivity versus the related receptors (human vasopressin 1a receptor, human vasopressin 1b receptor, and human oxytocin receptor), and pharmacokinetic profiles in rodents and other higher species. The truncated analogues show excellent potency at the V2R, increased systemic clearance, and shorter half-life in rats. Two compounds 19 (c(Bua-Cpa-Thi-Val-Asn-Cys)-Pro-Agm) and 38 (c(Bua-Cpa-Thi-Val-Asn-Cys)-Pro-d-Arg-NEt2) have been selected for clinical development for nocturia.


Subject(s)
Antidiuretic Agents/chemical synthesis , Antidiuretic Agents/pharmacology , Receptors, Vasopressin/agonists , Animals , Antidiuretic Agents/pharmacokinetics , Deamino Arginine Vasopressin/analogs & derivatives , Deamino Arginine Vasopressin/chemical synthesis , Deamino Arginine Vasopressin/pharmacology , Dose-Response Relationship, Drug , Drug Design , Drug Discovery , Half-Life , Humans , Nocturia/drug therapy , Rats , Receptors, Oxytocin/drug effects , Renal Agents/chemical synthesis , Renal Agents/pharmacology , Structure-Activity Relationship
5.
J Med Chem ; 59(7): 3129-39, 2016 Apr 14.
Article in English | MEDLINE | ID: mdl-26986178

ABSTRACT

Glucagon-like peptide-2 receptor agonists have therapeutic potential for the treatment of intestinal diseases. The native hGLP-2, a 33 amino acid gastrointestinal peptide, is not a suitable clinical candidate, due to its very short half-life in humans. In search of GLP-2 receptor agonists with better pharmacokinetic characteristics, a series of GLP-2 analogues containing Gly substitution at position 2, norleucine in position 10, and hydrophobic substitutions in positions 11 and/or 16 was designed and synthesized. In vitro receptor potency at the human GLP-2, selectivity vs the human GLP-1 and GCG receptors, and PK profile in rats were determined for the new analogues. A number of compounds more potent at the hGLP-2R than the native hormone, showing excellent receptor selectivity and very low systemic clearance (CL) were discovered. Analogues 69 ([Gly(2),Nle(10),D-Thi(11),Phe(16)]hGLP-2-(1-30)-NH2), 72 ([Gly(2),Nle(10),D-Phe(11),Leu(16)]hGLP-2-(1-33)-OH), 73 ([Gly(2),Nle(10),D-Phe(11),Leu(16)]hGLP-2-(1-33)-NH2), 81 ([Gly(2),Nle(10),D-Phe(11),Leu(16)]hGLP-2-(1-33)-NHEt), and 85 ([Gly(2),Nle(10),D-Phe(11),Leu(16)]hGLP-2-(1-33)-NH-((CH2)2O)4-(CH2)2-CONH2) displayed the desired profiles (EC50 (hGLP-2R) < 100 pM, CL in rat <0.3 mL/min/kg, selective vs hGLP-1R and hGCGR). Compound 73 (FE 203799) was selected as a candidate for clinical development.


Subject(s)
Glucagon-Like Peptide 2/agonists , Peptides/chemistry , Peptides/pharmacology , Structure-Activity Relationship , Amino Acid Sequence , Animals , Chemistry Techniques, Synthetic , Drug Stability , Glucagon-Like Peptide 2/chemistry , Glucagon-Like Peptide-1 Receptor/metabolism , Glucagon-Like Peptide-2 Receptor/metabolism , Humans , Intestine, Small/drug effects , Intestine, Small/growth & development , Male , Molecular Sequence Data , Norleucine/chemistry , Peptides/pharmacokinetics , Rats, Sprague-Dawley
6.
PLoS One ; 11(3): e0149615, 2016.
Article in English | MEDLINE | ID: mdl-26950065

ABSTRACT

STUDY QUESTION: What is the threshold for the prediction of moderate to severe or severe ovarian hyperstimulation syndrome (OHSS) based on the number of growing follicles ≥ 11 mm and/or estradiol (E2) levels? SUMMARY ANSWER: The optimal threshold of follicles ≥11 mm on the day of hCG to identify those at risk was 19 for both moderate to severe OHSS and for severe OHSS. Estradiol (E2) levels were less prognostic of OHSS than the number of follicles ≥ 11 mm. WHAT IS KNOWN ALREADY: In comparison to long gonadotropin-releasing hormone (GnRH) agonist protocols, the risk of severe OHSS is reduced by approximately 50% in a GnRH antagonist protocol for ovarian stimulation prior to in vitro fertilisation (IVF), while the two protocols provide equal chances of pregnancy per initiated cycle. Nevertheless, moderate to severe OHSS may still occur in GnRH antagonist protocols if human chorionic gonadotropin (hCG) is administered to trigger final oocyte maturation, especially in high responder patients. Severe OHSS following hCG trigger may occur with an incidence of 1-2% in a relatively young (aged 18 to 36 years) IVF population treated in a GnRH-antagonist protocol. STUDY DESIGN, SIZE, DURATION: From the Engage, Ensure and Trust trials, in total, 2,433 women who received hCG for oocyte maturation and for whom the number of follicles ≥ 11 mm and the level of E2 on the day of hCG administration were known were included in the analyses. PARTICIPANTS/MATERIALS, SETTING, METHODS: The threshold for OHSS prediction of moderate and severe OHSS was assessed in women treated with corifollitropin alfa or daily recombinant follicle stimulation hormone (rFSH) in a gonadotropin-releasing hormone (GnRH)-antagonist protocol. Receiver operating characteristics curve analyses for moderate to severe OHSS and severe OHSS were performed on the combined dataset and the sensitivity and specificity for the optimal threshold of number of follicles ≥ 11 mm, E2 levels on the day of (hCG), and a combination of both, were determined. MAIN RESULTS AND THE ROLE OF CHANCE: The optimal threshold of follicles ≥ 11 mm on the day of hCG to identify those at risk of moderate to severe OHSS was 19 (sensitivity and specificity 62.3% and 75.6%, respectively) and for severe OHSS was also 19 (sensitivity and specificity 74.3% and 75.3%, respectively). The positive and negative predictive values were 6.9% and 98.6%, respectively, for moderate to severe OHSS, and 4.2% and 99.5% for severe OHSS. LIMITATIONS, REASONS FOR CAUTION: This was a retrospective analysis of combined data from three trials following ovarian stimulation with two different gonadotropins. WIDER IMPLICATIONS OF THE FINDINGS: For patients with 19 follicles or more ≥11 mm on the day of hCG, measures to prevent the development of OHSS should be considered. Secondary preventive measures include cycle cancellation or coasting, use of a GnRH agonist to trigger final oocyte maturation in place of hCG and a freeze all strategy. TRIAL REGISTRATION: ClinicalTrials.gov NCT00702845 NCT00696800 NCT00696878.


Subject(s)
Chorionic Gonadotropin/adverse effects , Chorionic Gonadotropin/pharmacology , Follicle Stimulating Hormone, Human/adverse effects , Follicle Stimulating Hormone, Human/pharmacology , Gonadotropin-Releasing Hormone/antagonists & inhibitors , Ovarian Hyperstimulation Syndrome/chemically induced , Ovarian Hyperstimulation Syndrome/diagnosis , Adolescent , Adult , Clinical Trials as Topic , Estradiol/metabolism , Female , Hormone Antagonists/adverse effects , Hormone Antagonists/pharmacology , Humans , Organ Size/drug effects , Ovarian Follicle/drug effects , Ovarian Follicle/growth & development , Ovarian Hyperstimulation Syndrome/metabolism , Ovarian Hyperstimulation Syndrome/pathology , Ovulation Induction/adverse effects , Pregnancy , Prognosis , Retrospective Studies , Young Adult
7.
Epilepsy Behav ; 54: 14-9, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26615481

ABSTRACT

OBJECTIVE: Psychogenic nonepileptic seizures (PNESs) resemble epileptic seizures but originate from psychogenic rather than organic causes. Patients with PNESs are often unable or unwilling to reflect on underlying emotions. To gain more insight into the internal states of patients during PNES episodes, this study explored the time course of heart rate variability (HRV) measures, which provide information about autonomic nervous system functioning and arousal. METHODS: Heart rate variability measures were extracted from double-lead electrocardiography data collected during 1-7days of video-electroencephalography monitoring of 20 patients with PNESs, in whom a total number of 118 PNESs was recorded. Heart rate (HR) and HRV measures in time and frequency domains (standard deviation of average beat-to-beat intervals (SDANN), root mean square of successive differences (RMSSD), high-frequency (HF) power, low-frequency (LF) power, and very low-frequency (VLF) power) were averaged over consecutive five-minute intervals. Additionally, quantitative analyses of Poincaré plot parameters (SD1, SD2, and SD1/SD2 ratio) were performed. RESULTS: In the five-minute interval before PNES, HR significantly (p<0.05) increased (d=2.5), whereas SDANN (d=-0.03) and VLF power (d=-0.05) significantly decreased. During PNES, significant increases in HF power (d=0.0006), SD1 (d=0.031), and SD2 (d=0.016) were observed. In the five-minute interval immediately following PNES, SDANN (d=0.046) and VLF power (d=0.073) significantly increased, and HR (d=-5.1) and SD1/SD2 ratio (d=-0.14) decreased, compared to the interval preceding PNES. CONCLUSION: The results suggest that PNES episodes are preceded by increased sympathetic functioning, which is followed by an increase in parasympathetic functioning during and after PNES. Future research needs to identify the exact nature of the increased arousal that precedes PNES.


Subject(s)
Autonomic Nervous System/physiopathology , Heart Rate/physiology , Psychophysiologic Disorders/physiopathology , Seizures/physiopathology , Adult , Arousal/physiology , Electrocardiography , Emotions/physiology , Female , Humans , Male , Middle Aged , Psychophysiologic Disorders/psychology , Seizures/psychology , Young Adult
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2016: 1010-1013, 2016 Aug.
Article in English | MEDLINE | ID: mdl-28268495

ABSTRACT

Electroencephalography (EEG) is paramount for both retrospective analysis and real-time monitoring of epileptic seizures. Studies have shown that EEG-based seizure detection is very difficult for a specific epileptic population with intellectual disability due to the cerebral development disorders. In this work, a seizure detection method based on dynamic warping (DW) is proposed for patients with intellectual disability. It uses an EEG template of an individual subject's dominant seizure type, to extract the morphological features from EEG signals. A linear discriminant analysis (LDA) classifier is used to perform the seizure detection. Results show that the DW-based feature in the frequency domain is superior than that in the time domain, and the features extracted using wavelet transform method.


Subject(s)
Algorithms , Electroencephalography , Epilepsy/diagnosis , Intellectual Disability/complications , Seizures/diagnosis , Humans
9.
Annu Int Conf IEEE Eng Med Biol Soc ; 2015: 578-81, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26736328

ABSTRACT

Mental retardation (MR) is one of the most common secondary disabilities in people with Epilepsy. However, to our knowledge there are no reliable seizure detection methods specified for MR-patients. In this paper we performed a pilot study on a group of six patients with mental retardation to assess what EEG features potentially work well on this group. A group of EEG features on the time, frequency and spatio-temporal domain were extracted, the modified wrapper approach was then employed as an improved feature subset selection method. Results show high variance on obtained features subset across this group, meanwhile there exist some common features which characterize the high-frequency components of epileptic EEG signals.


Subject(s)
Epilepsy , Algorithms , Electroencephalography , Humans , Intellectual Disability , Pilot Projects , Seizures
10.
Hum Reprod ; 29(8): 1688-97, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24903202

ABSTRACT

STUDY QUESTION: Can predictors of low and high ovarian responses be identified in patients undergoing controlled ovarian stimulation (COS) in a GnRH antagonist protocol? SUMMARY ANSWER: Common prognostic factors for high and low ovarian responses were female age, antral follicle count (AFC) and basal serum FSH and LH. WHAT IS KNOWN ALREADY: Predictors of ovarian response have been identified in GnRH agonist protocols. With the introduction of GnRH antagonists to prevent premature LH rises during COS, and the gradual shift in use of long GnRH agonist to short GnRH antagonist protocols, there is a need for data on the predictability of ovarian response in GnRH antagonist cycles. STUDY DESIGN, SIZE, DURATION: A retrospective analysis of data from the Engage trial and validation with the Xpect trial. Prognostic models were constructed for high (>18 oocytes retrieved) and low (<6 oocytes retrieved) ovarian response. Model building was based on the recombinant FSH (rFSH) arm (n = 747) of the Engage trial. Multivariable logistic regression models were constructed in a stepwise fashion (P < 0.15 for entry). Validation based on calibration was performed in patients with equivalent treatment (n = 199) in the Xpect trial. PARTICIPANTS/MATERIALS, SETTING, METHODS: Infertile women with an indication for COS prior to IVF. The Engage and Xpect trials included patients of similar ethnic origins from North America and Europe who had regular menstrual cycles. The main causes of infertility were male factor, tubal factor and endometriosis. MAIN RESULTS AND THE ROLE OF CHANCE: In the Engage trial, 18.3% of patients had a high and 12.7% had a low ovarian response. Age, AFC, serum FSH and serum LH at stimulation Day 1 were prognostic for both high and low ovarian responses. Higher AFC and LH were associated with an increased chance of high ovarian response. Older age and higher FSH correlated with an increased chance of low ovarian response. Region (North America/Europe) and BMI were prognostic for high ovarian response, and serum estradiol at stimulation Day 1 was associated with low ovarian response. The area under the receiver operating characteristic (ROC) curve (AUC) for the model for a high ovarian response was 0.82. Sensitivity and specificity were 0.82 and 0.73; positive and negative predictive values were 0.40 and 0.95, respectively. The AUC for the model for a low ovarian response was 0.80. Sensitivity and specificity were 0.77 and 0.73, respectively; positive and negative predictive values were 0.29 and 0.96, respectively. In Xpect, 19.1% of patients were high ovarian responders and 16.1% were low ovarian responders. The slope of the calibration line was 0.81 and 1.35 for high and low ovarian responses, respectively, both not statistically different from 1.0. In summary, common prognostic factors for high and low ovarian responses were female age, AFC and basal serum FSH and LH. Simple multivariable models are presented that are able to predict both a too low or too high ovarian response in patients treated with a GnRH antagonist protocol and daily rFSH. LIMITATIONS, REASONS FOR CAUTION: Anti-Müllerian hormone was not included in the prediction modelling. WIDER IMPLICATIONS OF THE FINDINGS: The findings will help with the identification of patients at risk of a too high or too low ovarian response and individualization of COS treatment. STUDY FUNDING/COMPETING INTERESTS: Financial support for this study and the editorial work was provided by Merck, Sharp & Dohme Corp. (MSD), a subsidiary of Merck & Co. Inc., Whitehouse Station, NJ, USA. F.J.B. received a grant from CVZ to his institution; P.J.M.V. and H.W. are employees of MSD, and B.M.J.L.M. was an employee of MSD at the time of development of this manuscript. TRIAL REGISTRATION NUMBERS: NCT 00696800 and NCT00778999.


Subject(s)
Gonadotropin-Releasing Hormone/antagonists & inhibitors , Ovary/drug effects , Ovulation Induction , Adult , Decision Support Techniques , Female , Humans , Logistic Models , Patient-Specific Modeling , Prognosis , Retrospective Studies
11.
J Med Chem ; 57(12): 5306-17, 2014 Jun 26.
Article in English | MEDLINE | ID: mdl-24874785

ABSTRACT

Mothers of preterm babies frequently have difficulty establishing or maintaining lactation, thought to be due to interference with the milk ejection reflex. Administration of exogenous oxytocin can produce alveolar contraction and adequate breast emptying resulting in establishment of successful lactation. The natural hormone oxytocin is not receptor-selective and may cause hyponatremia via V2 receptor mediated antidiuresis. We have designed a series of potent oxytocin analogues containing N-alkylglycines in position 7 with excellent selectivity versus the related V1a, V1b, and V2 vasopressin receptors and short half-life: agonists 31 ([2-ThiMeGly(7)]dOT), 47 (carba-6-[Phe(2),BuGly(7)]dOT), 55 (carba-6-[3-MeBzlGly(7)]dOT), and 57 (carba-1-[4-FBzlGly(7)]dOT) have EC50 values at hOTR < 0.1 nM, selectivity ratios versus related human vasopressin receptors of >2000, IC50 at hV1aR > 500 nM, and total clearance in rats in the range of 60-80 mL min(-1) kg(-1). Compound 57 (FE 202767) is currently in clinical development for the treatment of preterm mothers requiring lactation support.


Subject(s)
Oligopeptides/chemistry , Oxytocin/analogs & derivatives , Oxytocin/chemistry , Peptides, Cyclic/chemistry , Receptors, Oxytocin/agonists , Animals , CHO Cells , Cricetulus , Genes, Reporter , Humans , Male , Oligopeptides/pharmacokinetics , Oligopeptides/pharmacology , Oxytocin/pharmacokinetics , Oxytocin/pharmacology , Peptides, Cyclic/pharmacokinetics , Peptides, Cyclic/pharmacology , Rats, Sprague-Dawley , Receptors, Oxytocin/genetics , Receptors, Vasopressin/agonists , Receptors, Vasopressin/genetics , Stereoisomerism , Structure-Activity Relationship
12.
J Psychiatr Res ; 54: 126-33, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24703187

ABSTRACT

OBJECTIVE: Psychogenic non-epileptic seizures (PNES) are epilepsy-like episodes which have an emotional rather than organic origin. Although PNES have often been related to the process of dissociation, the psychopathology is still poorly understood. To elucidate underlying mechanisms, the current study applied independent component analysis (ICA) on resting-state fMRI to investigate alterations within four relevant networks, associated with executive, fronto-parietal, sensorimotor, and default mode activation, and within a visual network to examine specificity of between-group differences. METHODS: Twenty-one patients with PNES without psychiatric or neurologic comorbidities and twenty-seven healthy controls underwent resting-state functional MR imaging at 3.0T (Philips Achieva). Additional neuropsychological testing included Raven's Matrices test and dissociation questionnaires. ICA with dual regression was used to identify resting-state networks in all participants, and spatial maps of the networks of interest were compared between patients and healthy controls. RESULTS: Patients displayed higher dissociation scores, lower cognitive performance and increased contribution of the orbitofrontal, insular and subcallosal cortex in the fronto-parietal network; the cingulate and insular cortex in the executive control network; the cingulate gyrus, superior parietal lobe, pre- and postcentral gyri and supplemental motor cortex in the sensorimotor network; and the precuneus and (para-) cingulate gyri in the default-mode network. The connectivity strengths within these regions of interest significantly correlated with dissociation scores. No between-group differences were found within the visual network, which was examined to determine specificity of between-group differences. CONCLUSIONS: PNES patients displayed abnormalities in several resting-state networks that provide neuronal correlates for an underlying dissociation mechanism.


Subject(s)
Brain Mapping , Brain/pathology , Dissociative Disorders/etiology , Psychophysiologic Disorders/physiopathology , Rest , Seizures , Adult , Brain/blood supply , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Neuropsychological Tests , Oxygen/blood , Seizures/complications , Seizures/pathology , Seizures/psychology , Statistics as Topic , Surveys and Questionnaires
13.
Crit Care Med ; 42(7): e525-e533, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24674922

ABSTRACT

OBJECTIVE: To determine if the selective vasopressin type 1a receptor agonist selepressin (FE 202158) is as effective as the mixed vasopressin type 1a receptor/vasopressin V2 receptor agonist vasopressor hormone arginine vasopressin when used as a titrated first-line vasopressor therapy in an ovine model of Pseudomonas aeruginosa pneumonia-induced severe sepsis. DESIGN: Prospective, randomized, controlled laboratory experiment. SETTING: University animal research facility. SUBJECTS: Forty-five chronically instrumented sheep. INTERVENTIONS: Sheep were anesthetized, insufflated with cooled cotton smoke via tracheostomy, and P. aeruginosa were instilled into their airways. They were then placed on assisted ventilation, awakened, and resuscitated with lactated Ringer's solution titrated to maintain hematocrit ± 3% from baseline levels. If, despite fluid management, mean arterial pressure fell by more than 10 mm Hg from baseline level, an additional continuous IV infusion of arginine vasopressin or selepressin was titrated to raise and maintain mean arterial pressure within no less than 10 mm Hg from baseline level. Effects of combination treatment of selepressin with the selective vasopressin V2 receptor agonist desmopressin were similarly investigated. MEASUREMENTS AND MAIN RESULTS: In septic sheep, MAP fell by ~30 mm Hg, systemic vascular resistance index decreased by ~50%, and ~7 L of fluid were retained over 24 hours; this fluid accumulation was partially reduced by arginine vasopressin and almost completely blocked by selepressin; and combined infusion of selepressin and desmopressin increased fluid accumulation to levels similar to arginine vasopressin treatment. CONCLUSIONS: Resuscitation with the selective vasopressin type 1a receptor agonist selepressin blocked vascular leak more effectively than the mixed vasopressin type 1a receptor/vasopressin V2 receptor agonist arginine vasopressin because of its lack of agonist activity at the vasopressin V2 receptor.


Subject(s)
Arginine Vasopressin/therapeutic use , Receptors, Vasopressin/agonists , Sepsis/drug therapy , Vasoconstrictor Agents/therapeutic use , Vasopressins/therapeutic use , Animals , Arginine Vasopressin/administration & dosage , Arginine Vasopressin/adverse effects , Drug Therapy, Combination , Hemodynamics , Pneumonia, Bacterial/complications , Pseudomonas aeruginosa , Random Allocation , Respiratory Mechanics , Sepsis/etiology , Sheep , Vasoconstrictor Agents/administration & dosage , Vasoconstrictor Agents/adverse effects , Vasopressins/administration & dosage , Vasopressins/adverse effects
14.
Psychol Med ; 44(12): 2465-74, 2014 Sep.
Article in English | MEDLINE | ID: mdl-24330830

ABSTRACT

Belief in free will has been a mainstay in philosophy throughout history, grounded in large part in our intuitive sense that we consciously control our actions and could have done otherwise. However, psychology and psychiatry have long sought to uncover mechanistic explanations for human behavior that challenge the notion of free will. In recent years, neuroscientific discoveries have produced a model of volitional behavior that is at odds with the notion of contra-causal free will and our sense of conscious agency. Volitional behavior instead appears to have antecedents in unconscious brain activity that is localizable to specific neuroanatomical structures. Updating notions of free will in favor of a continuous model of volitional self-control provides a useful paradigm to conceptualize and study some forms of psychopathology such as addiction and impulse control disorders. Similarly, thinking of specific symptoms of schizophrenia as disorders of agency may help to elucidate mechanisms of psychosis. Beyond clinical understanding and etiological research, a neuroscientific model of volitional behavior has the potential to modernize forensic notions of responsibility and criminal punishment in order to inform public policy. Ultimately, moving away from the language of free will towards the language of volitional control may result in an enhanced understanding of the very nature of ourselves.


Subject(s)
Brain/physiology , Mental Disorders/physiopathology , Personal Autonomy , Volition/physiology , Humans
15.
J Neurol Neurosurg Psychiatry ; 85(2): 174-9, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23175855

ABSTRACT

OBJECTIVE: Dissociation is a mental process with psychological and somatoform manifestations, which is closely related to hypnotic suggestibility and essentially shows the ability to obtain distance from reality. An increased tendency to dissociate is a frequently reported characteristic of patients with functional neurological symptoms and syndromes (FNSS), which account for a substantial part of all neurological admissions. This review aims to investigate what heart rate variability (HRV), EEG and neuroimaging data (MRI) reveal about the nature of dissociation and related conditions. METHODS: Studies reporting HRV, EEG and neuroimaging data related to hypnosis, dissociation and FNSS were identified by searching the electronic databases Pubmed and ScienceDirect. RESULTS: The majority of the identified studies concerned the physiological characteristics of hypnosis; relatively few investigations on dissociation related FNSS were identified. General findings were increased parasympathetic functioning during hypnosis (as measured by HRV), and lower HRV in patients with FNSS. The large variety of EEG and functional MRI investigations with diverse results challenges definite conclusions, but evidence suggests that subcortical as well as (pre)frontal regions serve emotion regulation in dissociative conditions. Functional connectivity analyses suggest the presence of altered brain networks in patients with FNSS, in which limbic areas have an increased influence on motor preparatory regions. CONCLUSIONS: HRV, EEG and (functional) MRI are sensitive methods to detect physiological changes related to dissociation and dissociative disorders such as FNSS, and can possibly provide more information about their aetiology. The use of such measures could eventually provide biomarkers for earlier identification of patients at risk and appropriate treatment of dissociative conditions.


Subject(s)
Brain Waves/physiology , Brain/physiopathology , Dissociative Disorders/physiopathology , Functional Neuroimaging , Heart Rate/physiology , Nervous System Diseases/physiopathology , Brain/physiology , Dissociative Disorders/complications , Humans , Hypnosis , Nervous System Diseases/complications , Nervous System Diseases/psychology
16.
Psychoneuroendocrinology ; 38(1): 155-65, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22776420

ABSTRACT

BACKGROUND: Nightmares and insomnia in PTSD are hallmark symptoms, yet poorly understood in comparison to the advances toward a biological framework for the disorder. According to polysomnography (PSG), only minor changes in sleep architecture were described. This warrants alternative methods for assessing sleep regulation in PTSD. METHODS: After screening for obstructive sleep apnea and period limb movement disorder, veterans with PTSD (n=13), trauma controls (TCs, n=17) and healthy controls (HCs, n=15) slept in our sleep laboratory on two consecutive nights with an IV catheter out of which blood was sampled every 20min from 22:00h to 08:00h. Nocturnal levels of plasma adrenocorticotropic hormone (ACTH), cortisol, melatonin were assessed in conjunction with PSG registration, as well as subjective sleep parameters. RESULTS: PTSD patients showed a significant increase in awakenings during sleep in comparison to both control groups. These awakenings were correlated with ACTH levels during the night, and with the subjective perception of sleep depth. Also, heart rate (HR) was significantly increased in PTSD patients as compared with both control groups. The diurnal regulation of ACTH, cortisol and melatonin appeared undisturbed. PTSD patients exhibited lower cortisol levels at borderline significance (p=0.056) during the first half of the night. ACTH levels and cortisol levels during the first half of the night were inversely related to slow wave sleep (SWS). CONCLUSION: This study suggests that hypothalamo-pituitary-adrenal (HPA) axis activity is related to sleep fragmentation in PTSD. Also, activity of the sympathetic nervous system (SNS) is increased during sleep in PTSD. Further research is necessary to explore the potential causal relationship between sleep problems and the activity of the HPA-axis and SNS in PTSD.


Subject(s)
Adrenocorticotropic Hormone/blood , Blood Specimen Collection , Hydrocortisone/blood , Hypothalamo-Hypophyseal System/physiopathology , Melatonin/blood , Pineal Gland/physiopathology , Pituitary-Adrenal System/physiopathology , Polysomnography , Sleep Deprivation/physiopathology , Stress Disorders, Post-Traumatic/physiopathology , Sympathetic Nervous System/physiopathology , Adult , Circadian Rhythm , Dreams , Heart Rate , Humans , Male , Middle Aged , Military Personnel/psychology , Pineal Gland/metabolism , Sleep Deprivation/blood , Sleep Deprivation/etiology , Stress Disorders, Post-Traumatic/blood , Stress Disorders, Post-Traumatic/complications , Veterans/psychology , Warfare , Wounds and Injuries/blood , Wounds and Injuries/complications , Wounds and Injuries/physiopathology
17.
Crit Care Med ; 40(6): 1957-60, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22488005

ABSTRACT

OBJECTIVE: To compare the effects on von Willebrand factor release of the mixed vasopressin type 1a and type 2 receptor agonist arginine vasopressin and the selective vasopressin type 1a receptor agonist FE 202158, [Phe2,Ile3,Hgn4,Orn(iPr)8]vasopressin, at doses required for the treatment of septic shock. DESIGN: Prospective, randomized, controlled laboratory experiment. SETTING: University animal research facility. SUBJECTS: Twenty-four chronically instrumented sheep. INTERVENTIONS: After a 5-day recovery from instrumentation, sheep were randomly assigned to receive a single intravenous bolus of the selective vasopressin type 2 receptor agonist desmopressin (1 nmol·kg(-1)) or continuous intravenous infusions of arginine vasopressin (3 pmol·kg(-1)·min(-1)), the selective vasopressin type 1a receptor agonist FE 202158 (10 pmol·kg(-1)·min(-1)), or vehicle (0.9% NaCl) (n = 6 each). MEASUREMENTS AND MAIN RESULTS: The von Willebrand factor antigen activity relative to hemoglobin concentration (vWF:Ag/Hb ratio) was measured at different time points during the 120-min study period. Maximal vWF:Ag/Hb ratio expressed as percentage of baseline level was significantly increased compared to vehicle-infused animals (3 ± 2%) in the desmopressin (40 ± 6%, p < .001) and arginine vasopressin groups (25 ± 4%, p < .001). The ratio for the FE 202158 group was not statistically different from the sham group (9 ± 2%, p = .208). Notably, maximal vWF:Ag/Hb ratio was lower in the FE 202158 than the arginine vasopressin group (p < .005). CONCLUSIONS: Unlike the mixed vasopressin type 1a receptor/vasopressin type 2 receptor agonist arginine vasopressin, the selective vasopressin type 1a receptor agonist FE 202158 does not release von Willebrand factor. Because von Willebrand factor is involved in coagulatory and inflammatory pathways during septic shock, future studies should clarify the role of the vasopressin type 2 receptor-mediated von Willebrand factor increase by arginine vasopressin and the potential benefit of selective vasopressin type 1a receptor-agonists like FE 202158.


Subject(s)
Arginine Vasopressin/pharmacology , Receptors, Vasopressin/agonists , Vasopressins/pharmacology , von Willebrand Factor/metabolism , Animals , Blood Coagulation/drug effects , Female , Prospective Studies , Random Allocation , Sheep , Shock, Septic/drug therapy , von Willebrand Factor/immunology
18.
Anal Bioanal Chem ; 402(4): 1471-80, 2012 Feb.
Article in English | MEDLINE | ID: mdl-21761109

ABSTRACT

X-ray radiographic images of paintings often show little or no contrast. In order to increase the contrast in radiographic images we measured the X-ray spectrum of a low power X-ray tube, after passing through the painting, with a high energy-resolution SDD detector. To obtain images, the detector is collimated with a 400 µm diameter pinhole and the painting was moved through the beam in the x and y-direction using a dwell time of a few seconds per pixel. The data obtained consists of a data cube of, typically, 200 × 200 pixels and a 512-channel X-ray spectrum for each pixel, spanning the energy range from 0 to 40 keV. Having the absorbance spectrum available for each pixel, we are able, a posteriori, to produce images by edge subtraction for any given element. In this way high contrast, element-specific, images can be obtained. Because of the high energy-resolution a much simpler edge subtraction algorithm can be applied. We also used principal-component imaging to obtain, in a more automated way, images with high contrast. Some of these images can easily be attributed to specific elements. It turns out that preprocessing of the spectral data is crucial for the success of the multivariate image processing.

19.
Vaccine ; 29(35): 5994-6001, 2011 Aug 11.
Article in English | MEDLINE | ID: mdl-21718744

ABSTRACT

Genital Chlamydia trachomatis infections often result in pelvic inflammatory disease and sequelae including infertility and ectopic pregnancies. In addition to the already established murine models, the development of other animal models is necessary to study the safety and efficacy of prototype vaccine candidates. The intravaginal infection of guinea pigs with C. trachomatis has been tested in three independent studies. The first two studies investigated the effect of hormonal treatment of the animals prior to infection with serovars D and E. The results showed that estradiol treatment was required for sustained infection. The third study conducted an immunization-challenge experiment to explore the feasibility of measuring protection in this guinea pig model. C. trachomatis bacteria were sampled using vaginal swabs and measured by qPCR. Using immunohistochemistry the bacteria were detected in the oviducts 19 days post-infection, indicating that the estradiol treatment resulted in ascending infection. Furthermore, immunization of guinea pigs with live EB formulated with ISCOM matrix led to reduction of cervico-vaginal shedding and diminished the severity of pathology. In this study we have developed a new guinea pig model of C. trachomatis female genital tract infection for the purpose of evaluating potential vaccine candidates.


Subject(s)
Chlamydia Infections/pathology , Chlamydia trachomatis/pathogenicity , Disease Models, Animal , Genital Diseases, Female/pathology , Animals , Antibodies, Bacterial/blood , Chlamydia Infections/microbiology , Chlamydia trachomatis/genetics , Chlamydia trachomatis/immunology , Chlamydia trachomatis/isolation & purification , Estradiol/administration & dosage , Female , Genital Diseases, Female/microbiology , Guinea Pigs , HeLa Cells , Humans , Oviducts/microbiology , Oviducts/pathology , Polymerase Chain Reaction , Vagina/microbiology , Vagina/pathology
20.
J Med Chem ; 54(13): 4388-98, 2011 Jul 14.
Article in English | MEDLINE | ID: mdl-21688787

ABSTRACT

[Arg(8)]vasopressin (AVP) produces vasoconstriction via V(1a) receptor (V(1a)R)-mediated vascular smooth muscle cell contraction and is being used to increase blood pressure in septic shock, a form of vasodilatory hypotension. However, AVP also induces V(2) receptor (V(2)R)-mediated antidiuresis, vasodilation, and coagulation factor release, all deleterious in septic shock. The V(1a)R agonist terlipressin (H-Gly(3)[Lys(8)]VP) also lacks selectivity vs the V(2)R and has sizably longer duration of action than AVP, preventing rapid titration of its vasopressor effect in the clinic. We designed and synthesized new short acting V(1a)R selective analogues of general structure [Xaa(2),Ile(3),Yaa(4),Zaa(8)]VP. The most potent and selective compounds in in vitro functional assays (e.g., [Phe(2),Ile(3),Asn(Me(2))(4),Orn(8)]VP (31), [Phe(2),Ile(3),Asn((CH(2))(3)OH)(4),Orn(8)]VP (34), [Phe(2),Ile(3),Hgn(4),Orn(iPr)(8)]VP (45), [Phe(2),Ile(3),Asn(Et)(4),Dab(8)]VP (49), [Thi(2),Ile(3),Orn(iPr)(8)]VP (59), [Cha(2),Ile(3),Asn(4),Orn(iPr)(8)]VP (68)) were tested by intravenous bolus in rats for duration of vasopressive action. Analogues 31, 34, 45, and 49 were as short-acting as AVP. Compound 45, FE 202158, is currently undergoing clinical trials in septic shock.


Subject(s)
Oligopeptides/chemical synthesis , Receptors, Vasopressin/agonists , Vasopressins/chemical synthesis , Animals , Blood Pressure/drug effects , HEK293 Cells , Humans , Male , Oligopeptides/chemistry , Oligopeptides/pharmacology , Rats , Rats, Wistar , Structure-Activity Relationship , Vasopressins/chemistry , Vasopressins/pharmacology
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