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1.
J Cell Sci ; 137(1)2024 01 01.
Article in English | MEDLINE | ID: mdl-38063216

ABSTRACT

In Chlamydomonas, the channel polycystin 2 (PKD2) is primarily present in the distal region of cilia, where it is attached to the axoneme and mastigonemes, extracellular polymers of MST1. In a smaller proximal ciliary region that lacks mastigonemes, PKD2 is more mobile. We show that the PKD2 regions are established early during ciliogenesis and increase proportionally in length as cilia elongate. In chimeric zygotes, tagged PKD2 rapidly entered the proximal region of PKD2-deficient cilia, whereas the assembly of the distal region was hindered, suggesting that axonemal binding of PKD2 requires de novo assembly of cilia. We identified the protein Small Interactor of PKD2 (SIP), a PKD2-related, single-pass transmembrane protein, as part of the PKD2-mastigoneme complex. In sip mutants, stability and proteolytic processing of PKD2 in the cell body were reduced and PKD2-mastigoneme complexes were absent from the cilia. Like the pkd2 and mst1 mutants, sip mutant cells swam with reduced velocity. Cilia of the pkd2 mutant beat with an increased frequency but were less efficient in moving the cells, suggesting a structural role for the PKD2-SIP-mastigoneme complex in increasing the effective surface of Chlamydomonas cilia.


Subject(s)
Chlamydomonas , Cilia , Cilia/metabolism , Chlamydomonas/genetics , Chlamydomonas/metabolism , Proteins/metabolism , Axoneme/metabolism
2.
bioRxiv ; 2023 Jun 14.
Article in English | MEDLINE | ID: mdl-37398320

ABSTRACT

In Chlamydomonas cilia, the ciliopathy-relevant TRP channel PKD2 is spatially compartmentalized into a distal region, in which PKD2 binds the axoneme and extracellular mastigonemes, and a smaller proximal region, in which PKD2 is more mobile and lacks mastigonemes. Here, we show that the two PKD2 regions are established early during cilia regeneration and increase in length as cilia elongate. In abnormally long cilia, only the distal region elongated whereas both regions adjusted in length during cilia shortening. In dikaryon rescue experiments, tagged PKD2 rapidly entered the proximal region of PKD2-deficient cilia whereas assembly of the distal region was hindered, suggesting that axonemal docking of PKD2 requires de novo ciliary assembly. We identified Small Interactor of PKD2 (SIP), a small PKD2-related protein, as a novel component of the PKD2-mastigoneme complex. In sip mutants, stability and proteolytic processing of PKD2 in the cell body were reduced and PKD2-mastigoneme complexes were absent from mutant cilia. Like the pkd2 and mst1 mutants, sip swims with reduced velocity. Cilia of the pkd2 mutant beat with normal frequency and bending pattern but were less efficient in moving cells supporting a passive role of the PKD2-SIP-mastigoneme complexes in increasing the effective surface of Chlamydomonas cilia.

3.
Psychiatr Serv ; 70(3): 239-242, 2019 03 01.
Article in English | MEDLINE | ID: mdl-30554561

ABSTRACT

In rural communities, primary care providers continue to provide mental health services, and about 70% of children and adolescents identified to have a psychiatric disorder never receive treatment. A telehealth model for providing integrated mental health services in a school-based health clinic has the potential to increase access to specialized care for the most vulnerable youths. This column provides an overview of the strategies used to implement and integrate such a model in West Virginia. Operationalization, barriers, challenges, and judicious resource use are discussed. Appropriate reimbursement for services and state-specific legislation to ensure consistent revenue to sustain the program are considered.


Subject(s)
Delivery of Health Care, Integrated/organization & administration , Mental Disorders/therapy , Mental Health Services/organization & administration , School Health Services/organization & administration , Telemedicine/organization & administration , Adolescent , Child , Health Services Accessibility , Humans , Rural Health Services , West Virginia
4.
Mol Psychiatry ; 23(1): 26-35, 2018 01.
Article in English | MEDLINE | ID: mdl-29133952

ABSTRACT

Major depressive disorder (MDD) is a complex and heterogeneous mood disorder, making it difficult to develop a generalized, pharmacological therapy that is effective for all who suffer from MDD. Through the fortuitous discovery of N-methyl-D-aspartate receptor (NMDAR) antagonists as effective antidepressants, we have gained key insights into how antidepressant effects can be produced at the circuit and molecular levels. NMDAR antagonists act as rapid-acting antidepressants such that relief from depressive symptoms occurs within hours of a single injection. The mode of action of NMDAR antagonists seemingly relies on their ability to activate protein-synthesis-dependent homeostatic mechanisms that restore top-down excitatory connections. Recent evidence suggests that NMDAR antagonists relieve depressive symptoms by forming new synapses resulting in increased excitatory drive. This event requires the mammalian target of rapamycin complex 1 (mTORC1), a signaling pathway that regulates synaptic protein synthesis. Herein, we review critical studies that shed light on the action of NMDAR antagonists as rapid-acting antidepressants and how they engage a neuron's or neural network's homeostatic mechanisms to self-correct. Recent studies notably demonstrate that a shift in γ-amino-butyric acid receptor B (GABABR) function, from inhibitory to excitatory, is required for mTORC1-dependent translation with NMDAR antagonists. Finally, we discuss how GABABR activation of mTORC1 helps resolve key discrepancies between rapid-acting antidepressants and local homeostatic mechanisms.


Subject(s)
Depressive Disorder, Major/pathology , Depressive Disorder, Major/physiopathology , Homeostasis/physiology , Neuronal Plasticity/physiology , Animals , Antidepressive Agents/therapeutic use , Depressive Disorder, Major/therapy , GABA Agents/pharmacology , GABA Agents/therapeutic use , Homeostasis/drug effects , Humans , Models, Molecular , Neuronal Plasticity/drug effects , Receptors, GABA/metabolism , Receptors, N-Methyl-D-Aspartate/antagonists & inhibitors , Receptors, N-Methyl-D-Aspartate/metabolism
5.
Mol Psychiatry ; 20(3): 298-310, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25560757

ABSTRACT

A single injection of N-methyl-D-aspartate receptor (NMDAR) antagonists produces a rapid antidepressant response. Lasting changes in the synapse structure and composition underlie the effectiveness of these drugs. We recently discovered that rapid antidepressants cause a shift in the γ-aminobutyric acid receptor (GABABR) signaling pathway, such that GABABR activation shifts from opening inwardly rectifiying potassium channels (Kir/GIRK) to increasing resting dendritic calcium signal and mammalian Target of Rapamycin activity. However, little is known about the molecular and biochemical mechanisms that initiate this shift. Herein, we show that GABABR signaling to Kir3 (GIRK) channels decreases with NMDAR blockade. Blocking NMDAR signaling stabilizes the adaptor protein 14-3-3η, which decouples GABABR signaling from Kir3 and is required for the rapid antidepressant efficacy. Consistent with these results, we find that key proteins involved in GABABR signaling bidirectionally change in a depression model and with rapid antidepressants. In socially defeated rodents, a model for depression, GABABR and 14-3-3η levels decrease in the hippocampus. The NMDAR antagonists AP5 and Ro-25-6981, acting as rapid antidepressants, increase GABABR and 14-3-3η expression and decrease Kir3.2. Taken together, these data suggest that the shift in GABABR function requires a loss of GABABR-Kir3 channel activity mediated by 14-3-3η. Our findings support a central role for 14-3-3η in the efficacy of rapid antidepressants and define a critical molecular mechanism for activity-dependent alterations in GABABR signaling.


Subject(s)
14-3-3 Proteins/metabolism , Antidepressive Agents/pharmacology , G Protein-Coupled Inwardly-Rectifying Potassium Channels/metabolism , Neurons/drug effects , Receptors, GABA-B/metabolism , 14-3-3 Proteins/genetics , Animals , Animals, Newborn , Cells, Cultured , Disease Models, Animal , Excitatory Amino Acid Antagonists/pharmacology , Excitatory Amino Acid Antagonists/therapeutic use , G Protein-Coupled Inwardly-Rectifying Potassium Channels/genetics , Immunoprecipitation , Male , Mice , Phenols/pharmacology , Phenols/therapeutic use , Piperidines/pharmacology , Piperidines/therapeutic use , Prefrontal Cortex/cytology , RNA, Messenger/metabolism , Rats , Rats, Sprague-Dawley , Receptors, GABA-B/genetics , Stress, Psychological/drug therapy , Stress, Psychological/pathology , Stress, Psychological/physiopathology , Swimming/psychology , Synaptosomes/drug effects , Synaptosomes/metabolism , Transduction, Genetic , Valine/analogs & derivatives , Valine/pharmacology , Valine/therapeutic use
6.
Neuropharmacology ; 73: 192-203, 2013 Oct.
Article in English | MEDLINE | ID: mdl-23752093

ABSTRACT

Administration of N-methyl-D-aspartate receptors (NMDAR) antagonists initiates a rapid anti-depressant response requiring mammalian Target of Rapamycin Complex 1 (mTORC1) kinase; however the molecular mechanism is unknown. We have determined that upon NMDAR blockade, dendritic γ-amino-butyric acid B receptors (GABABR) facilitate dendritic calcium entry. The GABABR-mediated increase in calcium signal requires the availability of dendritic L-type calcium channels. Moreover, GABABR can activate mTOR and increase mTOR dependent expression of BDNF under the same NMDAR blocked conditions. In vivo, blocking GABABR prevents the fast-acting, anti-depressant effect of the NR2B antagonist, Ro-25-6891, decreases active mTORC1 kinase, and reduces expression of BDNF and the AMPA receptor subunit GluA1. These findings propose a novel role for GABABRs in the antidepressant action of NR2B antagonists and as an initiator/regulator of mTORC1-mediated translation.


Subject(s)
Brain-Derived Neurotrophic Factor/metabolism , Cytoskeletal Proteins/metabolism , Multiprotein Complexes/metabolism , Nerve Tissue Proteins/metabolism , Receptors, GABA-B/metabolism , TOR Serine-Threonine Kinases/metabolism , 2-Amino-5-phosphonovalerate/pharmacology , Animals , Baclofen/pharmacology , Calcium/metabolism , Calcium Channels, L-Type/drug effects , Calcium Channels, L-Type/metabolism , Cells, Cultured , Excitatory Amino Acid Antagonists/pharmacology , GABA Antagonists/pharmacology , GABA-B Receptor Agonists/pharmacology , Hippocampus/metabolism , Humans , Immobility Response, Tonic/drug effects , Male , Mechanistic Target of Rapamycin Complex 1 , Mice , Organophosphorus Compounds/pharmacology , Piperidines/pharmacology , Prefrontal Cortex/drug effects , Prefrontal Cortex/metabolism , Primary Cell Culture , Receptors, AMPA/metabolism , Signal Transduction/drug effects
7.
J Obstet Gynecol Neonatal Nurs ; 30(6): 569-73, 2001.
Article in English | MEDLINE | ID: mdl-11724192

ABSTRACT

Supporting a family through the impending death of their infant challenges the health care team to create opportunities for the parents to complete the attachment process and begin to grieve. Even in the neonatal intensive-care unit, the family can be brought together with their child in activities that comfort and console, lay the foundation for positive memories, and initiate healing and closure after the death of the infant. Interventions for grieving parents are described in this article.


Subject(s)
Death , Neonatal Nursing/methods , Parents/psychology , Social Support , Adaptation, Psychological , Adult , Attitude of Health Personnel , Attitude to Death , Attitude to Health , Communication , Fear , Funeral Rites , Grief , Humans , Infant, Newborn , Intensive Care Units, Neonatal , Memory , Nurse's Role , Nursing Assessment , Parents/education , Patient Care Planning , Professional-Family Relations , Withholding Treatment
8.
Dev Psychopathol ; 12(1): 23-45, 2000.
Article in English | MEDLINE | ID: mdl-10774594

ABSTRACT

Parental emotions and behaviors that contribute to continuity and change in preschool children's externalizing problems were examined. Mothers and fathers were observed interacting with their children, and child-rearing styles were reported. Teachers, mothers, and children reported children's antisocial, oppositional behavior. Externalizing problems showed strong continuity 2 and 4 years later. Proactive parenting (i.e., supportive presence, clear instruction, and limit setting) predicted fewer behavior problems over time, after controlling for initial problems; the converse was true for parental anger. In contrast, the hypothesized ameliorative contribution of parents' positive emotion was not found. Parental contributions were most influential for children whose initial problems were in the clinical range. In particular, parental anger predicted continuation of problems over time. Paternal, as well as maternal, influences were identified. Examination of parental emotions and inclusion of fathers is important to research and intervention with young antisocial children.


Subject(s)
Affect , Child Behavior Disorders/diagnosis , Parent-Child Relations , Parents/psychology , Socialization , Child , Child Behavior Disorders/psychology , Child, Preschool , Female , Humans , Male , Play and Playthings , Predictive Value of Tests
10.
Int J Behav Med ; 5(3): 185-203, 1998.
Article in English | MEDLINE | ID: mdl-16250701

ABSTRACT

This study examined daily reports of pain, medication use, health care use, and activity reduction in adults with sickle cell disease, and their association with stress. Participants were 53 adults with sickle cell disease. They completed the Daily Hassles questionnaire at the start of the study, and they kept daily records of pain and pain response over the following 14 days. On average, patients reported pain on 6.5 days of the 14-day study period. The average pain intensity rating during a painful episode was 4.4 on a 10-point scale. Pain was most often managed at home. Patients took medication (analgesics and/or narcotics) on 80% of the days they experienced pain, and they were more likely to use medication, particularly narcotics, as pain levels increased. At higher pain levels some patients also utilized a range of health care services. On average, patients also cut back considerably on household and social activities, especially when pain reached a level of over 5 on the 10-point scale. Those who were employed, however, were likely to continue to work, even when in pain. In addition, stress had significant positive associations with average pain intensity as well as reductions in household and social activities. Furthermore, stress predicted activity reductions even after controlling for pain intensity. Stress was unrelated to medication and health care use in this study.

11.
Psychiatr Serv ; 48(12): 1582-3, 1997 Dec.
Article in English | MEDLINE | ID: mdl-9406268

ABSTRACT

This paper describes a program of rural satellite psychiatric clinics that has evolved within a Veterans Affairs medical center over the past three decades. The eight clinics are staffed by a single team that includes a psychiatrist, a psychiatric nurse, and two mental health technicians. The team travels to the eight sites at least once each month. The program has achieved its goal of providing outpatient screening, diagnosis, and treatment services to veterans who would otherwise have no access to specialty psychiatric care due to distance and transportation problems.


Subject(s)
Community Mental Health Services/organization & administration , Delivery of Health Care/methods , Hospitals, Veterans/organization & administration , Program Evaluation , Adult , Allied Health Personnel/statistics & numerical data , Delivery of Health Care/standards , Health Services Accessibility , Humans , Male , Patient Care Team/statistics & numerical data , Peripheral Nervous System Diseases/complications , Peripheral Nervous System Diseases/diagnosis , Psychiatric Nursing , Psychiatry , Psychotic Disorders/complications , Schizophrenia, Paranoid/drug therapy , United States
13.
Int J Behav Med ; 4(4): 364-77, 1997.
Article in English | MEDLINE | ID: mdl-16250724

ABSTRACT

This study was designed to examine whether brief training in cognitive coping skills would enhance pain coping strategies and alter pain perception in children and adolescents with sickle cell disease (SCD). Forty-nine participants with SCD were randomly assigned to either a cognitive coping skills condition or a standard care control condition. At pre- and posttesting, coping strategies and pain sensitivity using laboratory pain stimulation were measured. Results indicated that in comparison to the randomly assigned control condition, brief training in cognitive coping skills resulted in decreased negative thinking and lower pain ratings during low intensity laboratory pain stimulation.

14.
Psychosom Med ; 58(2): 138-42, 1996.
Article in English | MEDLINE | ID: mdl-8849630

ABSTRACT

Previous work from our group has examined the relationship between stress and immunodepression in medical students taking National Boards, Part I, and has described a relationship between stress intrusion scores (SIS) and immunodepression. We have also shown that a high proportion of individuals with generalized anxiety disorders (GAD) and panic disorders (PD) exhibit enhanced stress intrusion (SI) and are more prone to upper respiratory infections (URI). In the present preliminary study, we sought to establish a model to evaluate further the role of SI level on the extent of immunodepression. This would serve to assess in further studies the mechanism(s) of stress-induced immunodepression, its relationship to morbidity, and the role of therapeutic interventions. In 14 GAD patients and 14 controls, we correlated the expression of interleukin-2 receptors (CD25) on T lymphocytes stimulated with anti-CD3 in short term cultures and the frequency of URI and the SIS to assess the relationships among these parameters. A decreased expression of CD25 correlates linearly with increasing SIS and with a higher number of sick days with URI. These results support our previous observations that GAD patients are more susceptible to URI. Moreover, they suggest that there may be a direct relationship between immunodepression and morbidity and between SIS and immunodepression.


Subject(s)
Anxiety Disorders/etiology , Anxiety Disorders/immunology , HLA-DR Antigens/immunology , Receptors, Interleukin-2/immunology , Stress, Psychological/immunology , Stress, Psychological/psychology , Female , Humans , Male , T-Lymphocytes/immunology
15.
Br J Rheumatol ; 34(3): 270-3, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7728405

ABSTRACT

The role of diet in rheumatoid arthritis (RA) remains controversial and there have been no controlled studies on the use of elemental diet in the treatment of RA. Elemental diet is an hypoallergenic protein-free artificial diet consisting of essential amino acids, glucose, trace elements and vitamins. This study was carried out to assess the role of elemental diet and subsequent food reintroduction in RA. Elemental diet (E028) (and a small number of foods) was given to 24 patients with definite RA in order to induce a remission and then foods were gradually introduced. Where a food was suspected of causing symptoms it was removed from the diet. Twenty-three control patients supplemented their usual diet with E028. After the elemental diet there was a statistically significant improvement in the diet group in grip strength (P = 0.008) and Ritchie score (P = 0.006) but not in ESR, CRP, thermographic joint score or functional score. The diet group lost more weight than the control group and this correlated with the improvement in grip strength. This improvement was not present following food reintroduction. As the improvements took place in more subjective disease parameters and because of the difficulties in adequately blinding studies of diet in arthritis, a placebo effect must be considered. There was a high default rate, only 38% of those patients originally enrolled completed the study. In conclusion, this study shows that elemental diet can cause an improvement in a number of disease parameters in RA but this is not sustained by an individualized diet. It also illustrates some of the difficulties involved in the study of diet in arthritis.


Subject(s)
Arthritis, Rheumatoid/diet therapy , Adult , Arthritis, Rheumatoid/complications , Arthritis, Rheumatoid/physiopathology , Female , Food, Formulated , Hand Strength , Humans , Male , Pilot Projects , Severity of Illness Index , Weight Loss
16.
J Clin Psychiatry ; 54(1): 5-12, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8428898

ABSTRACT

BACKGROUND: Our investigation involved a quantitative literature review technique known as meta-analysis to compare the efficacy of three newer antidepressants and imipramine. METHOD: We examined seven major journals in psychiatry from 1980 through 1990, inclusive, and selected those investigations of imipramine, trazodone, bupropion, and fluoxetine that met our minimal criteria for interpretability. These criteria included: (1) the presence of a placebo control, (2) double-blind status, (3) the use of the Hamilton Rating Scale for Depression as a dependent variable measure, (4) the use of nongeriatric adults with a diagnosis of major depression by DSM or RDC standards, and (5) the presence of reported means and standard deviations in the investigation, or sufficient data that allowed such to be computed. Each study of four antidepressants was analyzed for an effect size of the drug investigated. The effect size allows for a determination of the efficacy of a particular drug as compared with placebo, measured in standard deviation units. RESULTS: The data indicated that all four agents are effective as compared with placebo. Furthermore, there is no evidence that the newer heterocyclic agents are less effective than imipramine, as an ANOVA showed no statistically significant difference between the effect sizes of the four antidepressants. CONCLUSION: These data are discussed in terms of characteristics of the various investigations and the need for further research comparing the efficacy of psychopharmacologic agents.


Subject(s)
Antidepressive Agents/therapeutic use , Depressive Disorder/drug therapy , Imipramine/therapeutic use , Bupropion/therapeutic use , Depressive Disorder/psychology , Fluoxetine/therapeutic use , Humans , Trazodone/therapeutic use
18.
Thromb Res ; 67(4): 419-27, 1992 Aug 15.
Article in English | MEDLINE | ID: mdl-1412220

ABSTRACT

Radioactivity from I125-labeled human platelets was measured to estimate the extent of binding of platelet surface proteins to immobilized thrombin. 1-3% of the radioactivity was bound with 10-20% of this amount apparently irreversibly bound to the thrombin matrix. Site-specific chemical modification of thrombin with pyridoxal-5'-phosphate, N-bromosuccinimide or tetranitromethane resulted in a variable reduction of the amount of radiolabel bound. When thrombin modified with H-D-PheProArg-chloromethyl ketone (PPACK) was coupled to the matrix, there was no difference in the binding of platelet membrane proteins when compared to a control thrombin preparation while thrombin modified with tosyl-Lys-chloromethyl ketone (TLCK) coupled to the matrix did not bind radiolabel any more effectively than albumin which served as the control. However, when thrombin was modified with PPACK after coupling to the agarose matrix, ability to bind radiolabel was lost. Thrombin bound to platelets remained catalytically active when assayed with a peptide nitroanilide substrate. These results suggest tight binding between thrombin and platelets that is not only not dependent on active site integrity but leaves the bound thrombin catalytically competent.


Subject(s)
Blood Platelets , Cell Separation/methods , Chromatography, Affinity/methods , Enzymes, Immobilized , Thrombin , Amino Acid Chloromethyl Ketones , Amino Acid Sequence , Blood Platelets/metabolism , Catalysis , Humans , Molecular Sequence Data , Platelet Membrane Glycoproteins/metabolism , Sepharose , Thrombin/metabolism , Tosyllysine Chloromethyl Ketone
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