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1.
Hum Reprod ; 38(4): 596-608, 2023 04 03.
Article in English | MEDLINE | ID: mdl-36763673

ABSTRACT

STUDY QUESTION: Can artificial intelligence (AI) algorithms developed to assist embryologists in evaluating embryo morphokinetics be enriched with multi-centric clinical data to better predict clinical pregnancy outcome? SUMMARY ANSWER: Training algorithms on multi-centric clinical data significantly increased AUC compared to algorithms that only analyzed the time-lapse system (TLS) videos. WHAT IS KNOWN ALREADY: Several AI-based algorithms have been developed to predict pregnancy, most of them based only on analysis of the time-lapse recording of embryo development. It remains unclear, however, whether considering numerous clinical features can improve the predictive performances of time-lapse based embryo evaluation. STUDY DESIGN, SIZE, DURATION: A dataset of 9986 embryos (95.60% known clinical pregnancy outcome, 32.47% frozen transfers) from 5226 patients from 14 European fertility centers (in two countries) recorded with three different TLS was used to train and validate the algorithms. A total of 31 clinical factors were collected. A separate test set (447 videos) was used to compare performances between embryologists and the algorithm. PARTICIPANTS/MATERIALS, SETTING, METHODS: Clinical pregnancy (defined as a pregnancy leading to a fetal heartbeat) outcome was first predicted using a 3D convolutional neural network that analyzed videos of the embryonic development up to 2 or 3 days of development (33% of the database) or up to 5 or 6 days of development (67% of the database). The output video score was then fed as input alongside clinical features to a gradient boosting algorithm that generated a second score corresponding to the hybrid model. AUC was computed across 7-fold of the validation dataset for both models. These predictions were compared to those of 13 senior embryologists made on the test dataset. MAIN RESULTS AND THE ROLE OF CHANCE: The average AUC of the hybrid model across all 7-fold was significantly higher than that of the video model (0.727 versus 0.684, respectively, P = 0.015; Wilcoxon test). A SHapley Additive exPlanations (SHAP) analysis of the hybrid model showed that the six first most important features to predict pregnancy were morphokinetics of the embryo (video score), oocyte age, total gonadotrophin dose intake, number of embryos generated, number of oocytes retrieved, and endometrium thickness. The hybrid model was shown to be superior to embryologists with respect to different metrics, including the balanced accuracy (P ≤ 0.003; Wilcoxon test). The likelihood of pregnancy was linearly linked to the hybrid score, with increasing odds ratio (maximum P-value = 0.001), demonstrating the ranking capacity of the model. Training individual hybrid models did not improve predictive performance. A clinic hold-out experiment was conducted and resulted in AUCs ranging between 0.63 and 0.73. Performance of the hybrid model did not vary between TLS or between subgroups of embryos transferred at different days of embryonic development. The hybrid model did fare better for patients older than 35 years (P < 0.001; Mann-Whitney test), and for fresh transfers (P < 0.001; Mann-Whitney test). LIMITATIONS, REASONS FOR CAUTION: Participant centers were located in two countries, thus limiting the generalization of our conclusion to wider subpopulations of patients. Not all clinical features were available for all embryos, thus limiting the performances of the hybrid model in some instances. WIDER IMPLICATIONS OF THE FINDINGS: Our study suggests that considering clinical data improves pregnancy predictive performances and that there is no need to retrain algorithms at the clinic level unless they follow strikingly different practices. This study characterizes a versatile AI algorithm with similar performance on different time-lapse microscopes and on embryos transferred at different development stages. It can also help with patients of different ages and protocols used but with varying performances, presumably because the task of predicting fetal heartbeat becomes more or less hard depending on the clinical context. This AI model can be made widely available and can help embryologists in a wide range of clinical scenarios to standardize their practices. STUDY FUNDING/COMPETING INTEREST(S): Funding for the study was provided by ImVitro with grant funding received in part from BPIFrance (Bourse French Tech Emergence (DOS0106572/00), Paris Innovation Amorçage (DOS0132841/00), and Aide au Développement DeepTech (DOS0152872/00)). A.B.-C. is a co-owner of, and holds stocks in, ImVitro SAS. A.B.-C. and F.D.M. hold a patent for 'Devices and processes for machine learning prediction of in vitro fertilization' (EP20305914.2). A.D., N.D., M.M.F., and F.D.M. are or have been employees of ImVitro and have been granted stock options. X.P.-V. has been paid as a consultant to ImVitro and has been granted stocks options of ImVitro. L.C.-D. and C.G.-S. have undertaken paid consultancy for ImVitro SAS. The remaining authors have no conflicts to declare. TRIAL REGISTRATION NUMBER: N/A.


Subject(s)
Artificial Intelligence , Embryo Transfer , Female , Pregnancy , Humans , Embryo Transfer/methods , Heart Rate, Fetal , Time-Lapse Imaging , Fertilization in Vitro , Pregnancy Rate
2.
RSC Adv ; 11(12): 7059-7069, 2021 02 04.
Article in English | MEDLINE | ID: mdl-35423179

ABSTRACT

Microemulsions are excellent systems for transdermal delivery of multifunctional drugs because they have the potential to improve drug absorption/permeation and handling limitations. Biocompatible polymers are used as a coating of microemulsions to avoid the interactions that can occur between the microemulsions and the skin. Thus, they protect and lubricate these transporter nanovesicles. In this paper, we studied decane/water microemulsions covered with hydrophobically modified PEO polymer (PEO-m). To reveal the effect of hydrophobically modified PEO (PEO-m) polymer on the shape, the micro-arrangement and the dynamics of the microemulsions, we used an integrated strategy combining Molecular Dynamics simulation (MD), Small-Angle Neutron Scattering experiments (SANS), and the Ornstein-Zernike integral equations with the Hypernetted Chain (HNC) closure relation. We determined the microemulsion shape in vitro using the renormalized intensities spectra from SANS experiments. We discussed the micro arrangements of microemulsions, in vitro and in silico, employing the pair correlation function g(r) and the structure factor S(q), obtained from the three approaches with good agreement. Thus, we used the validated MD simulations to calculate the microemulsion's dynamics properties that we discussed using the mean-squared displacement (MSD) and the diffusion coefficients. We found that the presence of moderate quantities of PEO-m, from 4 to 12 PEO-m per microemulsion, does not influence the microemulsion shape, increases the stability of the microemulsion, and slightly decrease the dynamics. Our in vitro and in silico results suggest that polymer incorporation, which has interesting in vivo implications, has no disadvantageous effects on the microemulsion properties.

3.
RSC Adv ; 11(18): 10400, 2021 Mar 10.
Article in English | MEDLINE | ID: mdl-35427040

ABSTRACT

[This corrects the article DOI: 10.1039/D0RA09804C.].

4.
RSC Adv ; 11(34): 20824-20835, 2021 Jun 09.
Article in English | MEDLINE | ID: mdl-35479396

ABSTRACT

We studied a large range of identical spherical oil/water microemulsion (O/W-MI) volume fractions. The O/W-MIs are stabilized by cetylpyridinium chloride ionic surfactant (CpCl) and octanol cosurfactant and dispersed in salt water. We grafted different numbers of dodecyl-(polyEthylene oxide)227-dodecyl triblock copolymer that we note (n(D-PEO227-D)), where n varies from 0 to 12. We accomplished the grafting process by replacing a small amount of CpCl and octanol with the appropriate n(D-PEO227-D). The aim is to determine the interaction/structure relationship of the covered microemulsions. Precisely, we are interested in a quantitative investigation of the influence of volume fraction Φ, temperature (T), and n(D-PEO227-D) on the microemulsion sol/gel transition. To this end, we first study the uncoated microemulsion structure depending only on Φ. Second, we determine the coated microemulsions structure as a function of n(D-PEO227-D) for different Φ. Third, we examine the effect of temperature on the uncoated and coated microemulsion. We show that the sol/gel transition is controlled by the three main parameters, Φ, T, and n(D-PEO227-D). Accordingly, the uncoated microemulsion sol/gel transition, at ambient temperature, occurred for Φ ≃ 33.65%. By increasing Φ, the O/W-MIs show a glass state, which occurs, along with the gel state, at Φ ≃ 37% and arises clearly at Φ ≃ 60%. The coated O/W-MI sol/gel transition is found to be linearly dependent on n(D-PEO227-D) and takes place for Φ ≃ 26.5% for n(D-PEO227-D) = 12. Ordinarily, the decrease in temperature leads to gel formation of microemulsions for low Φ. Additionally, in this work, we found that the gelation temperature increases linearly with n(D-PEO227-D). Thus, the parameter n(D-PEO227-D) can control the sol/gel transition of the O/W-MIs at ambient temperature and moderate Φ.

5.
Med Mal Infect ; 50(8): 648-651, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32798610

ABSTRACT

Less than 20% of African adolescents aged 10-19 years are aware of their HIV status, whereas HIV screening remains the gateway to care and while AIDS has become the leading cause of death among adolescents in Sub-Saharan Africa. According to the UNAIDS target, scalable HIV testing strategies specific to various age groups, populations, and geographical areas must be implemented to end the AIDS epidemic by 2030. Many African countries have implemented policies supporting HIV self-testing (HIVST). Evidence of practicability and efficiency of HIVST in Sub-Saharan Africa settings has been reported, including HIVST data among adolescents. Adapted strategies of HIVST are urgently needed to promote HIV testing among adolescents living in sub-Saharan Africa.


Subject(s)
HIV Infections , Self-Testing , Adolescent , Africa South of the Sahara/epidemiology , HIV Infections/diagnosis , HIV Infections/epidemiology , HIV Testing , Humans
6.
RSC Adv ; 10(59): 36155-36163, 2020 Sep 28.
Article in English | MEDLINE | ID: mdl-35517086

ABSTRACT

Molecular dynamics simulation (MD) is used to study the static and dynamic properties of positively charged decane/water microemulsions, for various volume fractions Φ (2.8%, 6.98%, 14%, and 26.5%). An effective hybrid potential combining three potentials, namely the hard-sphere repulsive potential, the van der Waals attractive potential, and the Yukawa repulsive potential, is used to describe the microemulsion interactions. The microemulsion shape is determined using the renormalized spectra in Porod representation. The appropriate potential parameters are tested using the Ornstein-Zernike integral equation approach with the Hypernetted Chain (HNC) closure relation by a comparison between the structure factor calculated from HNC and that obtained from Small Angle Neutron Scattering experiments (SANS). Thus, the micro arrangements of microemulsions have been analyzed using the pair correlation function g(r) and the structure factor S(q) obtained from HNC, SANS, and MD simulation using these parameters. The microemulsion dynamic properties were discussed using the mean-square displacement (MSD) and the diffusion coefficient D c calculated from MD simulations.

7.
Med Sante Trop ; 28(2): 144-149, 2018 May 01.
Article in English | MEDLINE | ID: mdl-29997071

ABSTRACT

HIV self-testing constitutes a new complementary strategy for HIV testing for general populations as well as "key" populations such as sex workers and their clients, men who have sex with men, and young people; it may help to reach the UNAIDS 90-90-90 objectives by 2020. In Africa, many pilot studies have been conducted, mainly in English-speaking countries, and they have demonstrated the high acceptability, practicability and clinical performance of HIV self-testing. Innovative strategies, including the translation of HIV self-test instructions for use into vernacular languages in association with educational pictograms, should be developed and evaluated in sub-Saharan Africa to implement HIV self-testing.


Subject(s)
AIDS Serodiagnosis/methods , HIV Infections/diagnosis , Self Care , Africa , Humans , Practice Guidelines as Topic
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2017: 475-478, 2017 Jul.
Article in English | MEDLINE | ID: mdl-29059913

ABSTRACT

Epilepsy is a neurological disorder for which the electroencephalogram (EEG) is the most important diagnostic tool. In particular, this diagnosis heavily depends on the detection of interictal (between seizures) paroxysmal epileptic discharges (IPED) in the EEG. This is a time-consuming task requiring significant training and experience. Automatic detection of these EEG patterns would greatly assist visual inspections of human readers. We present a new method, which allows automatic detection of IPED based on discrete wavelet decomposition and a random forest classifier. The algorithm was trained and cross validated using 17 subjects with scalp EEG and 10 subjects with intracranial EEG. The performance of this method reached 62% recall and 26% precision for surface EEG subjects and 63% recall and 53% precision for intracranial EEG subjects. Thus, the method hereby proposed has great potential for diagnosis support in clinical environments.


Subject(s)
Electrocorticography , Algorithms , Epilepsy , Humans , Seizures
9.
Neuropharmacology ; 76 Pt A: 68-79, 2014 Jan.
Article in English | MEDLINE | ID: mdl-23891615

ABSTRACT

Methylene blue (MB) belongs to the phenothiazinium family. It has been used to treat a variety of human conditions and has beneficial effects on the central nervous system in rodents with and without brain alteration. The present study was designed to test whether chronic MB treatment taken after (therapeutic effect) or before (preventive effect) the onset of beta-amyloid pathology influences cognition in a transgenic mouse model (APP/PS1). In addition, the present study aims at revealing whether these behavioral effects might be related to brain alteration in beta-amyloid deposition. To this end, we conducted an in vivo study and compared two routes of drug administration, drinking water versus intraperitoneal injection. Results showed that transgenic mice treated with MB orally or following intraperitoneal injection were protected from cognitive impairments in a variety of social, learning, and exploratory tasks. Immunoreactive beta-amyloid deposition was significantly reduced in the hippocampus and adjacent cortex in MB-treated transgenic mice. Interestingly, these beneficial effects were observed independently of beta-amyloid load at the time of MB treatment. This suggests that MB treatment is beneficial at both therapeutic and preventive levels. Using solid-state High Resolution Magic Angle Spinning Nuclear Magnetic Resonance (HRMAS-NMR), we showed that MB administration after the onset of amyloid pathology significantly restored the concentration of two metabolites related to mitochondrial metabolism, namely alanine and lactate. We conclude that MB might be useful for the therapy and prevention of Alzheimer's disease. This article is part of the Special Issue entitled 'The Synaptic Basis of Neurodegenerative Disorders'.


Subject(s)
Alzheimer Disease/drug therapy , Alzheimer Disease/prevention & control , Methylene Blue/pharmacology , Methylene Blue/therapeutic use , Neuroprotective Agents/pharmacology , Neuroprotective Agents/therapeutic use , Administration, Oral , Alanine/metabolism , Alzheimer Disease/metabolism , Alzheimer Disease/pathology , Amyloid beta-Peptides/metabolism , Animals , Avoidance Learning/drug effects , Cerebral Cortex/drug effects , Cerebral Cortex/metabolism , Discrimination, Psychological/drug effects , Disease Models, Animal , Hippocampus/drug effects , Hippocampus/metabolism , Injections, Intraperitoneal , Lactic Acid/metabolism , Male , Methylene Blue/administration & dosage , Mice , Mice, Transgenic , Mitochondria/drug effects , Mitochondria/metabolism , Motor Activity/drug effects , Nesting Behavior/drug effects
10.
Brain Behav Immun ; 26(6): 880-5, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22401992

ABSTRACT

The myeloid differentiation primary response gene 88 (MyD88) product is the most common adaptor protein implicated in Toll-like and interleukin receptor (TIR) domain signaling and thus plays an important role in the innate immune system. Despite the fact that the MyD88-dependent pathway has emerged as an important player in cell death processes described in several animal models of neurodegenerative disorders, the contribution of this pathway to specific behavioral phenotypes has been largely ignored. To understand the full implication of this pathway, we tested MyD88(-/-) mice for both motor and cognitive functions in normal conditions. MyD88(-/-) mice displayed impaired spatial and working memory as detected by the Barnes maze, the water T-maze and the passive avoidance tests. Furthermore, MyD88(-/-) mice demonstrated hypolocomotion in the open-field and wheel activity systems, as well as impairments in motor coordination and balance using the pole test and the rotarod. Our findings shed light on behavioral alterations that are associated with the deletion of the MyD88 protein in physiological conditions. These behavioral effects should be taken into consideration when assessing the role of the MyD88-dependent pathway in various infectious and non-infectious conditions.


Subject(s)
Cognition Disorders/genetics , Cognition Disorders/psychology , Movement Disorders/genetics , Movement Disorders/physiopathology , Myeloid Differentiation Factor 88/deficiency , Animals , Avoidance Learning/physiology , Hot Temperature , Maze Learning/physiology , Memory, Short-Term/physiology , Mice , Mice, Inbred C57BL , Mice, Knockout , Motor Activity/genetics , Motor Activity/physiology , Pain Measurement , Postural Balance/genetics , Postural Balance/physiology , Reaction Time/physiology
11.
Reprod Biomed Online ; 19 Suppl 4: 4309, 2009.
Article in English | MEDLINE | ID: mdl-20034411

ABSTRACT

BCL2-associated X protein (BAX) and B-cell leukaemia/lymphoma gene-2 (BCL2), which are, respectively, pro- and anti-apoptotic proteins of the BCL2 gene family, participate in the mitochondria-dependent apoptosis pathway. A correlation between low incidence of apoptosis in cumulus cells and oocyte maturation has previously been suggested in ovarian stimulation. However, little is known in unprimed ovaries. These authors have investigated whether BAX and BCL2 expression in cumulus cells affects the competency of in-vitro matured oocytes. We have studied 100 cumulus-oocyte-complexes (COC) recovered from unprimed ovaries of 13 women diagnosed with polycystic ovary syndrome (PCOS) and undergoing in-vitro maturation (IVM) with their informed consent. COC were matured for 24 h in a specific maturation medium and the cumulus was stripped from the oocyte. BAX and BCL2 mRNA content was measured in each COC using real-time polymerase chain reaction. We found that BCL2 mRNA expression was significantly higher in cumulus cells associated with mature oocytes than those associated with immature oocytes while BAX mRNA concentrations did not vary in cumulus cells. Regarding fertilization, higher BCL2 mRNA content was found in cumulus cells enclosing fertilized oocytes (0.140 versus 0.075; P = 0.03). These results suggest that BCL2 expression is strongly associated with the ability of oocytes to complete nuclear maturation and to be fertilized.


Subject(s)
Cumulus Cells/chemistry , Genes, bcl-2/genetics , Oocytes/growth & development , RNA, Messenger/analysis , Apoptosis/physiology , Cells, Cultured , Cumulus Cells/physiology , Female , Fertilization in Vitro , Humans , Polycystic Ovary Syndrome , bcl-2-Associated X Protein/genetics
12.
Br J Cancer ; 101(2): 312-9, 2009 Jul 21.
Article in English | MEDLINE | ID: mdl-19568237

ABSTRACT

BACKGROUND: The RAS/RAF/MEK/ERK pathway is involved in the balance between melanocyte proliferation and differentiation. The same pathway is constitutively activated in cutaneous and uveal melanoma (UM) and related to tumour growth and survival. Whereas mutant BRAF and NRAS are responsible for the activation of the RAS/RAF/MEK/ERK pathway in most cutaneous melanoma, mutations in these genes are usually absent in UM. METHODS: We set out to explore the RAS/RAF/MEK/ERK pathway and used mitogen-activated protein kinase profiling and tyrosine kinase arrays. RESULTS: We identified Src as a kinase that is associated with ERK1/2 activation in UM. However, low Src levels and reduced ERK1/2 activation in metastatic cell lines suggest that proliferation in metastases can become independent of Src and RAS/RAF/MEK/ERK signalling. Inhibition of Src led to the growth reduction of primary UM cultures and cell lines, whereas metastatic cell line growth was only slightly reduced. CONCLUSION: We identified Src as an important kinase and a potential target for treatment in primary UM. Metastasis cell lines seemed largely resistant to Src inhibition and indicate that in metastases treatment, a different approach may be required.


Subject(s)
Melanoma/enzymology , Uveal Neoplasms/enzymology , src-Family Kinases/metabolism , Cell Growth Processes/physiology , Cell Line, Tumor , Enzyme Activation , Humans , Melanoma/pathology , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Neoplasm Metastasis , Uveal Neoplasms/pathology
13.
Genes Brain Behav ; 8(2): 143-8, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19077180

ABSTRACT

Neuropsychiatric signs are critical in primary caregiving of Alzheimer patients and yet have been relatively ignored in murine models. In the present study, APPswe/PS1 bigenic mice had higher levels of irritability than non-transgenic controls as measured in the touch escape test. Moreover, APPswe/PS1 mice showed poorer nest building than controls and a higher duration of immobility in the forced swimming assay. These results are concordant with the hypothesis of increased apathy and depression-like behavior in an Alzheimer's disease model. In addition, APPswe/PS1 bigenic mice were deficient in retention of passive avoidance learning and left-right discrimination learning, concordant with previous findings in other Alzheimer-like models.


Subject(s)
Alzheimer Disease/genetics , Alzheimer Disease/psychology , Amyloid beta-Protein Precursor/genetics , Behavior, Animal/physiology , Cognition/physiology , Presenilin-1/genetics , Animals , Avoidance Learning/physiology , Depression/psychology , Discrimination Learning/physiology , Escape Reaction/physiology , Female , Functional Laterality/physiology , Irritable Mood , Male , Maze Learning/physiology , Mice , Mice, Transgenic , Nesting Behavior , Swimming/psychology
14.
Reprod Biomed Online ; 16(2): 250-6, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18284882

ABSTRACT

In-vitro maturation of oocytes (IVM) is a new IVF technology developed in order to avoid iatrogenic complications of standard IVF treatments. This technique is particularly useful in patients suffering from polycystic ovary syndrome (PCOS) who are concerned with the risk of ovarian hyperstimulation syndrome. This technique is nowadays routinely practised in many international centres. However, the efficiency of this technique needs to be improved for a better support of maturation conditions to maximize oocyte developmental competence. In order to improve IVM results, the efficiency of two IVM media was retrospectively compared. Ninety-three PCOS candidates undergoing their first IVM cycle were included in this study, and IVM was conducted with TCM-199 or IVM-Medicult medium. This is the first study comparing two maturation media. Both media resulted in the same results concerning total oocyte maturation, fertilization, early embryo development and pregnancy rates.


Subject(s)
Culture Media/pharmacology , Embryo Culture Techniques , Oocytes/drug effects , Oogenesis/drug effects , Adult , Cells, Cultured , Culture Media/chemistry , Embryo Transfer , Female , Fertilization in Vitro , Humans , Oocytes/physiology , Pregnancy , Pregnancy Rate , Retrospective Studies
17.
J Cell Biochem ; 74(2): 168-80, 1999 Aug 01.
Article in English | MEDLINE | ID: mdl-10404387

ABSTRACT

The human spliceosomal Sm B/B' proteins are essential for the biogenesis of the snRNP particles. B/B' proteins contain several clusters of the PPPPGM/IR sequence, which occurs within the C-terminus of Sm B/B'. This sequence is very similar to the PPPPPGHR sequence of the cytoplasmic tail of the CD2 receptor and closely resembles the class II of SH3 ligands, suggesting a similarly important role. We report that a monoclonal antibody (3E10) against the PPPPPGHR sequence recognizes spliceosomal Sm B/B' proteins. Proteins that are specifically immunoprecipitated by 3E10 include Sm B, B', D1, D2, D3, E, F, and G. However, unlike Y12 and other anti-Sm immunoprecipitates, 3E10 immunoprecipitates appear to lack the U1 snRNP-specific proteins A and C and U snRNAs. These findings indicate that 3E10 recognizes a subset of Sm protein core and suggest the presence of snRNA-free Sm protein complex(es) in vivo. We propose that the epitope binding for 3E10 may become unaccessible upon interactions of Sm proteins and their subsequent incorporation into the core particles. The Sm proline-rich sequences may have an important role in mediating protein-protein interactions necessary for the proper snRNP core assembly or function, or both. To our knowledge, 3E10 is the first well characterized mAb specific for a subclass of polyproline-arg motif recognizing Sm B/B' and CD2 proteins. 3E10 antibody can be used to further characterize the nature of protein components in the snRNA-free Sm subcore protein complex(es) that are formed during the snRNP core assembly steps.


Subject(s)
Antibodies, Monoclonal/immunology , Autoantigens/metabolism , Dipeptides/immunology , Ribonucleoproteins, Small Nuclear/metabolism , Amino Acid Sequence , Antibody Specificity , Arginine/immunology , Autoantigens/chemistry , Autoantigens/immunology , Epitopes/immunology , Humans , Jurkat Cells , Molecular Sequence Data , Peptides/immunology , Precipitin Tests , RNA, Small Nuclear/metabolism , Ribonucleoproteins, Small Nuclear/chemistry , Ribonucleoproteins, Small Nuclear/immunology , Spliceosomes/metabolism , snRNP Core Proteins
18.
J Cell Biochem ; 73(2): 153-63, 1999 May 01.
Article in English | MEDLINE | ID: mdl-10227379

ABSTRACT

We have identified a 36 kD phosphoprotein that forms a complex with spliceosomal small nuclear ribonucleoproteins in lymphocyte extracts. This 36 kD protein is differentially phosphorylated in transformed human lymphoid cell lines and is regulated by IL-2 in peripheral blood T cells. We purified the 36 kD protein from human lymphocytes by employing a combination of immuno-affinity chromatography and preparative two-dimensional gel electrophoresis. Internal amino acid sequence analysis of the purified protein yielded two peptides that had perfect matches with sequences in the human protein serine/threonine phosphatase 6 (PP6). Using degenerate primers corresponding to the peptides, we obtained from a human T lymphocyte cDNA library a DNA fragment whose sequence is homologous to an EST cDNA clone (R05547). The predicted amino acid sequence of this clone showed over 98% sequence identity to human PP6. The identification of an IL-2 regulated type 6 protein serine/threonine phosphatase in lymphocytes was further substantiated by immunoblotting with anti-peptide antibodies. These findings suggest that PP6 is a component of a signaling pathway regulating cell cycle progression in response to IL-2 receptor stimulation.


Subject(s)
Interleukin-2/pharmacology , Phosphoprotein Phosphatases/metabolism , Amino Acid Sequence , Cell Cycle , Cloning, Molecular , DNA, Complementary , Electrophoresis, Gel, Two-Dimensional , Enzyme Activation , Expressed Sequence Tags , Humans , Jurkat Cells , Lymphocytes/cytology , Lymphocytes/enzymology , Molecular Sequence Data , Phosphoprotein Phosphatases/isolation & purification , Phosphorylation , Sequence Homology, Amino Acid
19.
Neurobiol Learn Mem ; 65(2): 113-20, 1996 Mar.
Article in English | MEDLINE | ID: mdl-8833100

ABSTRACT

Cerebellar damage occurs during developmental stages in three mutant mice (staggerer, hot-foot, and lurcher), causing disturbances in posture and equilibrium. During three tests of motor coordination, the performances of staggerer mutants was inferior to that of normal mice and did not improve with extended practice for up to 7 days of training. The sensorimotor performance of hot-foot mutants and of lurcher mutants was also lower than that of normal mice. Nevertheless, hot-foot mutants showed evidence of learning in two of the three tests and lurcher mutants in all three tests. Cerebellar atrophy in the latter two mutants did not prevent sensorimotor learning, but instead impaired their ability to reach the same level of performance as that of normal mice.


Subject(s)
Atrophy/physiopathology , Cerebellum/physiopathology , Learning , Mice, Mutant Strains , Animals , Behavior, Animal , Female , Male , Mice
20.
J Comp Physiol A ; 178(1): 101-4, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8568721

ABSTRACT

Hot-foot mutant mice, characterized by defective innervation of Purkinje cells and an ataxic gait, were less active than normal mice in a T-maze. In spontaneous alternation testing with either single or multiple trials, hot-foot mutants, contrary to normal mice, did not alternate above chance. Moreover, the mutants had a higher number of errors and higher escape latencies in a water-filled Z-maze. These results indicate that in addition to motor coordination deficits, these cerebellar mutants have deficits in spatial learning and perseverate choices of maze arms.


Subject(s)
Cerebellum/physiology , Maze Learning , Motor Activity/physiology , Animals , Female , Male , Mice , Mice, Mutant Strains , Spatial Behavior/physiology , Time Factors
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