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1.
Development ; 149(13)2022 07 01.
Article in English | MEDLINE | ID: mdl-35662330

ABSTRACT

Neural tube closure (NTC) is a fundamental process during vertebrate development and is indispensable for the formation of the central nervous system. Here, using Xenopus laevis embryos, live imaging, single-cell tracking, optogenetics and loss-of-function experiments, we examine the roles of convergent extension and apical constriction, and define the role of the surface ectoderm during NTC. We show that NTC is a two-stage process with distinct spatiotemporal contributions of convergent extension and apical constriction at each stage. Convergent extension takes place during the first stage and is spatially restricted at the posterior tissue, whereas apical constriction occurs during the second stage throughout the neural plate. We also show that the surface ectoderm is mechanically coupled with the neural plate and its movement during NTC is driven by neural plate morphogenesis. Finally, we show that an increase in surface ectoderm resistive forces is detrimental for neural plate morphogenesis.


Subject(s)
Neural Tube , Neurulation , Animals , Morphogenesis/physiology , Neural Plate , Neurulation/physiology , Xenopus laevis
2.
Mol Psychiatry ; 28(5): 2008-2017, 2023 05.
Article in English | MEDLINE | ID: mdl-37147389

ABSTRACT

Using machine learning, we recently decomposed the neuroanatomical heterogeneity of established schizophrenia to discover two volumetric subgroups-a 'lower brain volume' subgroup (SG1) and an 'higher striatal volume' subgroup (SG2) with otherwise normal brain structure. In this study, we investigated whether the MRI signatures of these subgroups were also already present at the time of the first-episode of psychosis (FEP) and whether they were related to clinical presentation and clinical remission over 1-, 3-, and 5-years. We included 572 FEP and 424 healthy controls (HC) from 4 sites (Sao Paulo, Santander, London, Melbourne) of the PHENOM consortium. Our prior MRI subgrouping models (671 participants; USA, Germany, and China) were applied to both FEP and HC. Participants were assigned into 1 of 4 categories: subgroup 1 (SG1), subgroup 2 (SG2), no subgroup membership ('None'), and mixed SG1 + SG2 subgroups ('Mixed'). Voxel-wise analyses characterized SG1 and SG2 subgroups. Supervised machine learning analyses characterized baseline and remission signatures related to SG1 and SG2 membership. The two dominant patterns of 'lower brain volume' in SG1 and 'higher striatal volume' (with otherwise normal neuromorphology) in SG2 were identified already at the first episode of psychosis. SG1 had a significantly higher proportion of FEP (32%) vs. HC (19%) than SG2 (FEP, 21%; HC, 23%). Clinical multivariate signatures separated the SG1 and SG2 subgroups (balanced accuracy = 64%; p < 0.0001), with SG2 showing higher education but also greater positive psychosis symptoms at first presentation, and an association with symptom remission at 1-year, 5-year, and when timepoints were combined. Neuromorphological subtypes of schizophrenia are already evident at illness onset, separated by distinct clinical presentations, and differentially associated with subsequent remission. These results suggest that the subgroups may be underlying risk phenotypes that could be targeted in future treatment trials and are critical to consider when interpreting neuroimaging literature.


Subject(s)
Psychotic Disorders , Schizophrenia , Humans , Brazil , Brain/diagnostic imaging , Magnetic Resonance Imaging
3.
Clin Auton Res ; 34(2): 233-252, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38709357

ABSTRACT

PURPOSE: We conducted a meta-analysis to determine the effect of hyperoxia on muscle sympathetic nerve activity in healthy individuals and those with cardio-metabolic diseases. METHODS: A comprehensive search of electronic databases was performed until August 2022. All study designs (except reviews) were included: population (humans; apparently healthy or with at least one chronic disease); exposures (muscle sympathetic nerve activity during hyperoxia or hyperbaria); comparators (hyperoxia or hyperbaria vs. normoxia); and outcomes (muscle sympathetic nerve activity, heart rate, blood pressure, minute ventilation). Forty-nine studies were ultimately included in the meta-analysis. RESULTS: In healthy individuals, hyperoxia had no effect on sympathetic burst frequency (mean difference [MD] - 1.07 bursts/min; 95% confidence interval [CI] - 2.17, 0.04bursts/min; P = 0.06), burst incidence (MD 0.27 bursts/100 heartbeats [hb]; 95% CI - 2.10, 2.64 bursts/100 hb; P = 0.82), burst amplitude (P = 0.85), or total activity (P = 0.31). In those with chronic diseases, hyperoxia decreased burst frequency (MD - 5.57 bursts/min; 95% CI - 7.48, - 3.67 bursts/min; P < 0.001) and burst incidence (MD - 4.44 bursts/100 hb; 95% CI - 7.94, - 0.94 bursts/100 hb; P = 0.01), but had no effect on burst amplitude (P = 0.36) or total activity (P = 0.90). Our meta-regression analyses identified an inverse relationship between normoxic burst frequency and change in burst frequency with hyperoxia. In both groups, hyperoxia decreased heart rate but had no effect on any measure of blood pressure. CONCLUSION: Hyperoxia does not change sympathetic activity in healthy humans. Conversely, in those with chronic diseases, hyperoxia decreases sympathetic activity. Regardless of disease status, resting sympathetic burst frequency predicts the degree of change in burst frequency, with larger decreases for those with higher resting activity.


Subject(s)
Hyperoxia , Muscle, Skeletal , Sympathetic Nervous System , Humans , Hyperoxia/physiopathology , Sympathetic Nervous System/physiology , Sympathetic Nervous System/physiopathology , Muscle, Skeletal/physiology , Muscle, Skeletal/innervation , Heart Rate/physiology
4.
J Clin Psychol ; 80(1): 186-197, 2024 01.
Article in English | MEDLINE | ID: mdl-37850971

ABSTRACT

BACKGROUND: Misophonia is often referred to as a disorder that is characterized by excessive negative emotional responses, including anger and anxiety, to "trigger sounds" which are typically day-to-day sounds, such as those generated from people eating, chewing, and breathing. Misophonia (literally "hatred of sounds") has commonly been understood within an auditory processing framework where sounds cause distress due to aberrant processing in the auditory and emotional systems of the brain. However, a recent proposal suggests that it is the perceived action (e.g., mouth movement in eating/chewing sounds as triggers) of the trigger person, and not the sounds per se, that drives the distress in misophonia. Since observation or listening to sounds of actions of others are known to prompt mimicry in perceivers, we hypothesized that mimicking the action of the trigger person may be prevalent in misophonia. Apart from a few case studies and anecdotal information, a relation between mimicking and misophonia has not been systematically evaluated. METHOD: In this work, we addressed this limitation by collecting data on misophonia symptoms and mimicry behavior using online questionnaires from 676 participants. RESULTS: Analysis of these data shows that (i) more than 45% of individuals with misophonia reported mimicry, indicating its wide prevalence, (ii) the tendency to mimic varies in direct proportion to misophonia severity, (iii) compared to other human and environmental sounds, trigger sounds of eating and chewing are more likely to trigger mimicking, and (iv) the act of mimicking provides some degree of relief from distress to people with misophonia. CONCLUSION: This study shows prevalence of mimicry and its relation to misophonia severity and trigger types. The theoretical framework of misophonia needs to incorporate the phenomenon of mimicry and its effect on management of misophonia distress.


Subject(s)
Emotions , Hearing Disorders , Humans , Prevalence , Surveys and Questionnaires
5.
Exp Eye Res ; 225: 109282, 2022 12.
Article in English | MEDLINE | ID: mdl-36265576

ABSTRACT

Aging is a multifactorial process that affects the entire organism by cumulative alterations. Visual function impairments that go along with aging are commonly observed, causing lower visual acuity, lower contrast sensitivity, and impaired dark adaptation. Electroretinogram analysis revealed that the amplitudes of rod- and cone-mediated responses are reduced in aged mice and humans. Reports suggested that age-related changes observed in both rod and cone photoreceptor functionality were linked to oxidative stress regulation or free radical production homeostasis. Interestingly, several recent reports linked the fragile X mental retardation protein (FMRP) cellular activity with oxidative stress regulation in several tissue including brain tissue where FMRP participates to the response to stress via protein translation in neurite or is involved in free radical production and abnormal glutathione homeostasis. Based on these recent literatures, we raised the question about the effect of FMRP absence in the aging retina of Fmr1-/y compared to their WT littermates. Indeed, up to now, only young or adult mice (<6 months) were investigated and have shown a specific retinal phenotype. Herein, we demonstrated that Fmr1-/y mice do not present the aging effect on retinal function observed in WT littermates since ERG a- and b-waves amplitudes as well as oscillatory potentials amplitudes were not collapsed with age (12/18 months old). Absence of FMRP and its consequences seem to protect the retina against aging effect, rising a pivotal role of FMRP in retinal aging process.


Subject(s)
Electroretinography , Fragile X Mental Retardation Protein , Retina , Animals , Mice , Aging/physiology , Contrast Sensitivity , Fragile X Mental Retardation Protein/genetics , Retina/pathology , Retinal Cone Photoreceptor Cells/metabolism
6.
J Intellect Disabil Res ; 66(7): 577-616, 2022 07.
Article in English | MEDLINE | ID: mdl-35698311

ABSTRACT

BACKGROUND: Little is known about how to evaluate relationships and sex education (RSE) delivered to students with intellectual disability and what stakeholders perceive are important outcomes. The present study aimed to systematically review existing studies on outcomes of RSE, as the first step in the development of a core outcome set (COS) for students with intellectual disability. METHOD: A systematic literature process included two stages: (1) searching for studies reporting on RSE outcomes for students with intellectual disability and (2) studies reporting on measurement properties (e.g. validity, reliability and responsiveness) of standardised instruments identified in stage 1. RESULTS: A total of 135 RSE outcomes were extracted from 42 studies: 43 outcomes for students in secondary education and 92 outcomes for students in further education. No RSE outcomes were reported for primary education. Outcomes referred to the human body, hygiene, relationships, sexuality, sex and its consequences, inappropriate and appropriate social and sexual behaviour, keeping safe, emotional vocabulary and positive self-esteem. Outcomes were predominantly knowledge-based, rather than relating to skills and attitudes development. Students with intellectual disability, parents and teachers perceive different RSE outcomes meaningful. Five instruments were used to measure the outcomes, but none have established psychometric properties with this population. CONCLUSIONS: The comprehensive list of RSE outcomes for students with intellectual disability will be used to inform the next steps of a Core Outcome Set needed for RSE evaluations in research and education settings. There is an urgent need to develop standardised instruments validated for students with intellectual disability.


Subject(s)
Intellectual Disability , Sex Education , Humans , Intellectual Disability/psychology , Reproducibility of Results , Sexuality , Students/psychology
7.
Cell Commun Signal ; 19(1): 3, 2021 01 07.
Article in English | MEDLINE | ID: mdl-33413438

ABSTRACT

BACKGROUND: Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase that is overexpressed or activated in several advanced-stage solid cancers. It is known to play both kinase-dependent and -independent roles in promoting tumor progression and metastasis. Numerous inhibitors, targeting either the enzymatic or scaffolding activities of FAK have been generated, with varying degree of success. Here, we describe a novel approach to site-specifically target both kinase-dependent and -independent FAK functions at focal adhesions (FAs), the primary sites at which the kinase exerts its activity. METHODS: We took advantage of the well-characterized interactions between the paxillin LD motifs and the FAK FAT domain and generated a polypeptide (LD2-LD3-LD4) expected to compete with interactions with paxillin. Co-immunoprecipitation experiments were performed to examine the interaction between the LD2-LD3-LD4 polypeptide and FAK. The effects of LD2-LD3-LD4 in the localization and functions of FAK, as well as FA composition, were evaluated using quantitative immunofluorescence, cell fractionation, FA isolation and Western Blot analysis. Live cell imaging, as well as 2-D migration and cell invasion assays were used to examine the effects on FA turnover and tumor cell migration and invasion. RESULTS: Expression of the LD2-LD3-LD4 polypeptide prevents FAK localization at FAs, in a controlled and dose-dependent manner, by competing with endogenous paxillin for FAK binding. Importantly, the LD2-LD3-LD4 peptide did not otherwise affect FA composition or integrin activation. LD2-LD3-LD4 inhibited FAK-dependent downstream integrin signaling and, unlike existing inhibitors, also blocked FAK's scaffolding functions. We further show that LD2-LD3-LD4 expression markedly reduces FA turnover and inhibits tumor cell migration and invasion. Finally, we show that dimers of a single motif, linked through a flexible linker of the proper size, are sufficient for the displacement of FAK from FAs and for inhibition of tumor cell migration. This work raises the possibility of using a synthetic peptide as an antimetastatic agent, given that effective displacement of FAK from FAs only requires dimers of a single LD motif linked by a short flexible linker. CONCLUSION: In conclusion, these results suggest that FAK displacement from FAs is a promising new strategy to target critical processes implicated in cancer progression and metastasis. Video abstract.


Subject(s)
Focal Adhesion Protein-Tyrosine Kinases/metabolism , Focal Adhesions/metabolism , Neoplasms/metabolism , Neoplasms/pathology , Paxillin/metabolism , Cell Line , Cell Movement , Disease Progression , Humans , Paxillin/genetics , Protein Domains
8.
J Environ Manage ; 295: 113146, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34186317

ABSTRACT

In Europe, regions in the Mediterranean area share common characteristics in terms of high sensitivity to climate change impacts. Does this translate into specificities regarding climate action that could arise from these Mediterranean characteristics? This paper sheds light on regional and local climate mitigation actions of the Mediterranean Europe, focusing on the plans to reduce greenhouse gases emissions in a representative sample of 51 regions and 73 cities across 9 Mediterranean countries (Croatia, Cyprus, France, Greece, Italy, Malta, Portugal, Slovenia, Spain). The study investigates: (i) the availability of local and regional mitigation plans, (ii) their goals in term of greenhouse gas emissions reduction targets on the short and medium-long term, and (iii) the impact of transnational climate networks on such local and regional climate mitigation planning. Results of this study indicate an uneven and fragmented planning, that shows a Mediterranean West-East divide, and a link with population size. However, overall, both regional and city action seem insufficiently ambitious with regards to meeting the Paris Agreement, at least at city level. While national frameworks are currently weak in influencing regional and local actions, transnational networks seem to be engaging factors for commitment (at city level) and ambitiousness (at regional level). The uneven and fragmented progress revealed by this study, does not align with the characteristics shared by investigated regions and cities in terms of environmental, socio-political, climatic and economic conditions. The results support the call of a common green deal at the Mediterranean level to further address specific Mediterranean challenges and related needs. This will allow to capitalise on available resources, generate local-specific knowledge, build capacities, and support Mediterranean regions and cities in preparing the next generation of more ambitious mitigation plans.


Subject(s)
Climate Change , Cities , Croatia , Cyprus , Europe , France , Greece , Italy , Mediterranean Region , Paris , Portugal , Slovenia , Spain
9.
J Biol Chem ; 292(2): 488-504, 2017 Jan 13.
Article in English | MEDLINE | ID: mdl-27895123

ABSTRACT

We previously identified focal adhesion kinase (FAK) as an important regulator of ciliogenesis in multiciliated cells. FAK and other focal adhesion (FA) proteins associate with the basal bodies and their striated rootlets and form complexes named ciliary adhesions (CAs). CAs display similarities with FAs but are established in an integrin independent fashion and are responsible for anchoring basal bodies to the actin cytoskeleton during ciliogenesis as well as in mature multiciliated cells. FAK down-regulation leads to aberrant ciliogenesis due to impaired association between the basal bodies and the actin cytoskeleton, suggesting that FAK is an important regulator of the CA complex. However, the mechanism through which FAK functions in the complex is not clear, and in this study we examined the role of this protein in both ciliogenesis and ciliary function. We show that localization of FAK at CAs depends on interactions taking place at the amino-terminal (FERM) and carboxyl-terminal (FAT) domains and that both domains are required for proper ciliogenesis and ciliary function. Furthermore, we show that an interaction with another CA protein, paxillin, is essential for correct localization of FAK in multiciliated cells. This interaction is indispensable for both ciliogenesis and ciliary function. Finally, we provide evidence that despite the fact that FAK is in the active, open conformation at CAs, its kinase activity is dispensable for ciliogenesis and ciliary function revealing that FAK plays a scaffolding role in multiciliated cells. Overall these data show that the role of FAK at CAs displays similarities but also important differences compared with its role at FAs.


Subject(s)
Avian Proteins/metabolism , Basal Bodies/enzymology , Focal Adhesion Protein-Tyrosine Kinases/metabolism , Actin Cytoskeleton/enzymology , Actin Cytoskeleton/genetics , Animals , Avian Proteins/genetics , Chickens , Cilia/enzymology , Cilia/genetics , Focal Adhesion Protein-Tyrosine Kinases/genetics , Paxillin/genetics , Paxillin/metabolism , Protein Domains , Xenopus Proteins/genetics , Xenopus Proteins/metabolism , Xenopus laevis
10.
J Endocrinol Invest ; 40(9): 999-1005, 2017 Sep.
Article in English | MEDLINE | ID: mdl-28386795

ABSTRACT

PURPOSE: Physical activity is an effective therapeutic tool for cardiovascular risk prevention. However, exercise aerobic capacity of patients with type 1 diabetes (T1DM) has not been thoroughly investigated. Aim of the present study is to evaluate exercise aerobic capacity in patients with T1DM compared to a normal control population. METHODS: This observational study included 17 T1DM patients and 17 matched healthy volunteers. Cardiopulmonary exercise test (CPET) was conducted on an electronically-braked cycle ergometer. Blood samples were collected for evaluation of glycemia and lactate levels. RESULTS: Mean oxygen uptake at peak exercise (V'O2,peak) was significantly lower in T1DM subjects (V'O2,peak T1DM 2200 ± 132ml/min vs V'O2,peak Healthy subjects of 2659 ± 120 ml/min p = 0.035). Cardiovascular response analysis did not show statistically significant differences. Respiratory exchange ratio (RER) was significantly higher in healthy subjects at peak exercise and at the first minute of recovery (p = 0.022, p = 0.024). Peak exercise lactate levels were significantly higher in healthy subjects. There was no statistical correlation between CPET results and diabetes-related parameters. CONCLUSIONS: Patients affected by T1DM have a worse exercise tolerance than normal subjects. The two groups differed by RER which can be greatly influenced by the substrate type utilized to produce energy. Because of the impaired carbohydrate utilization, T1DM subjects may use a larger amount of lipid substrates, such hypothesis could be strengthened by the lower lactate levels found in T1DM group at peak exercise. The lack of correlation between exercise tolerance and disease-related variables suggests that the alterations found could be independent from the glycemic levels.


Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus, Type 1/metabolism , Exercise Test/methods , Exercise Tolerance/physiology , Exercise/physiology , Heart Rate/physiology , Adult , Diabetes Mellitus, Type 1/physiopathology , Female , Humans , Male , Oxygen Consumption/physiology
11.
J Hum Nutr Diet ; 30(6): 700-708, 2017 12.
Article in English | MEDLINE | ID: mdl-28419643

ABSTRACT

OBJECTIVES: Post-prandial hypertriglyceridaemia (P-HTG) is associated with cardiovascular disease. This association is of paramount importance during menopause, which is also related to reduced high-density lipoprotein-cholesterol (HDLc) and elevated triglyceride (TG) levels. We aimed to provide a self-assesing tool to screen for P-HTG in menopausal women who were normotriglyceridaemic at fasting and adhered to a Mediterranean-style eating pattern. METHODS: We performed oral fat loading tests (OFLT) in combination with self-measurements of diurnal capillary TG at fixed time-points (DC-TG) in 29 healthy menopausal women. TG levels >220 mg dL-1 at any given time during the OFLT served as diagnostic criteria for P-HTG. Subsequently, DC-TG profiles were examined to determine the best mealtime (breakfast, lunch or dinner), as well as optimal cut-off points to classify these women as having P-HTG according to the OFLT. Insulin resistance was defined as the upper tertile of the homeostatic model assessment of insulin resistance. RESULTS: We found that, despite having normal fasting TG levels, P-HTG was highly prevalent (approximately 40%). Moreover, self-assessed 3-h post-lunch TG levels >165 mg dL-1 increased the odds of having hypo-HDL cholesterolaemia by 14.1-fold (P = 0.026) and the odds of having insulin resistance by 31.6-fold (P = 0.007), adjusted for total fat intake in women adhering to a Mediterranean eating pattern having their highest energy intake at lunch. CONCLUSIONS: Self-assessed 3-h post-lunch TG can be used to study post-prandial TG metabolism in Southern European menopausal women who are normotriglyceridaemic at fasting. Characterising an individual's post-prandial response may help menopausal women to evaluate their risk of cardiovascular disease.


Subject(s)
Cholesterol, HDL/blood , Hypertriglyceridemia/blood , Insulin Resistance , Postprandial Period , Triglycerides/blood , Blood Glucose/metabolism , Body Mass Index , C-Peptide/blood , Diet, Mediterranean , Fasting , Female , Glycated Hemoglobin/metabolism , Humans , Hypertriglyceridemia/diagnosis , Insulin/blood , Lunch , Menopause , Middle Aged , Patient Compliance , Waist Circumference
12.
Development ; 140(20): 4266-76, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24048589

ABSTRACT

FAK is a non-receptor tyrosine kinase involved in a wide variety of biological processes and crucial for embryonic development. In this manuscript, we report the generation of a new FAK dominant negative (FF), composed of the C terminus (FRNK) and the FERM domain of the protein. FF, unlike FRNK and FERM, mimics the localization of active FAK in the embryo, demonstrating that both domains are necessary to target FAK to its complexes in vivo. We show that the FERM domain has a role in the recruitment of FAK on focal adhesions and controls the dynamics of the protein on these complexes. Expression of FF blocks focal adhesion turnover and, unlike FRNK, acts as a dominant negative in vivo. FF expression in Xenopus results in an overall phenotype remarkably similar to the FAK knockout in mice, including loss of mesodermal tissues. Expression of FF in the animal cap revealed a previously unidentified role of FAK in early morphogenesis and specifically epiboly. We show that a fibronectin-derived signal transduced by FAK governs polarity and cell intercalation. Finally, failure of epiboly results in severe gastrulation problems that can be rescued by either mechanical or pharmacological relief of tension within the animal cap, demonstrating that epiboly is permissive for gastrulation. Overall, this work introduces a powerful new tool for the study of FAK, uncovers new roles for FAK in morphogenesis and reveals new mechanisms through which the FERM domain regulates the localization and dynamics of FAK.


Subject(s)
Focal Adhesion Kinase 1/metabolism , Morphogenesis , Xenopus laevis/embryology , Animals , Cell Adhesion , Cell Movement , Focal Adhesion Kinase 1/chemistry , Focal Adhesion Kinase 1/genetics , Focal Adhesions/metabolism , Gastrulation , Gene Expression Regulation, Developmental , Mesoderm/metabolism , Protein Structure, Tertiary , Protein-Tyrosine Kinases/metabolism , Signal Transduction , Xenopus laevis/genetics , Xenopus laevis/metabolism
13.
Am J Public Health ; 105(1): 9-12, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25393184

ABSTRACT

As the nation's premier biomedical research agency, the National Institutes of Health (NIH) has supported most of the research that underlies the prevention services that are provided to citizens in the United States and around the world. Within the NIH, the Office of Disease Prevention (ODP) has as its mission to improve the public health by increasing the scope, quality, dissemination, and effect of prevention research supported by the NIH. In today's environment, the ODP needs to focus its efforts to address this mission. To do so, the ODP has developed a strategic plan for 2014 to 2018. We provide background on the ODP and key points from the strategic plan.

14.
Dev Biol ; 384(1): 83-100, 2013 Dec 01.
Article in English | MEDLINE | ID: mdl-24076278

ABSTRACT

Calpains are a family of calcium-dependent intracellular cysteine proteases that regulate several physiological processes by limited cleavage of different substrates. The role of Calpain2 in embryogenesis is not clear with conflicting evidence from a number of mouse knockouts. Here we report the temporal and spatial expression of Calpain2 in Xenopus laevis embryos and address its role in Xenopus development. We show that Calpain2 is expressed maternally with elevated expression in neural tissues and that Calpain2 activity is spatially and temporally regulated. Using a Calpain inhibitor, a dominant negative and a morpholino oligonoucleotide we demonstrate that impaired Calpain2 activity results in defective convergent extension both in mesodermal and neural tissues. Specifically, Calpain2 downregulation results in loss of tissue polarity and blockage of mediolateral intercalation in Keller explants without affecting adherens junction turnover. We further show that Calpain2 is activated in response to Wnt5a and that the inhibitory effect of Wnt5a expression on animal cap elongation can be rescued by blocking Calpain2 function. This suggests that Calpain2 activity needs to be tightly regulated during convergent extension. Finally we show that expression of Xdd1 blocks the membrane translocation of Calpain2 suggesting that Calpain2 activation is downstream of Dishevelled. Overall our data show that Calpain2 activation through the Wnt/Ca(2+) pathway and Dishevelled can modulate convergent extension movements.


Subject(s)
Calcium/metabolism , Calpain/genetics , Signal Transduction , Wnt Proteins/metabolism , Xenopus Proteins/genetics , Xenopus laevis/metabolism , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Animals , Calpain/metabolism , Dishevelled Proteins , Down-Regulation , Embryo, Nonmammalian/cytology , Embryo, Nonmammalian/metabolism , Phosphoproteins/genetics , Phosphoproteins/metabolism , Wnt Proteins/genetics , Xenopus Proteins/metabolism , Xenopus laevis/embryology , Xenopus laevis/genetics
15.
Dev Biol ; 380(2): 243-58, 2013 Aug 15.
Article in English | MEDLINE | ID: mdl-23685253

ABSTRACT

Nucleotide binding protein 1 (Nubp1) is a highly conserved phosphate loop (P-loop) ATPase involved in diverse processes including iron-sulfur protein assembly, centrosome duplication and lung development. Here, we report the cloning, expression and functional characterization of Xenopus laevis Nubp1. We show that xNubp1 is expressed maternally, displays elevated expression in neural tissues and is required for convergent extension movements and neural tube closure. In addition, xNubp1knockdown leads to defective ciliogenesis of the multi-ciliated cells of the epidermis as well as the monociliated cells of the gastrocoel roof plate. Specifically, xNubp1 is required for basal body migration, spacing and docking in multi-ciliated cells and basal body positioning and axoneme elongation in monociliated gastrocoel roof plate cells. Live imaging of the different pools of actin and basal body migration during the process of ciliated cell intercalation revealed that two independent pools of actin are present from the onset of cell intercalation; an internal network surrounding the basal bodies, anchoring them to the cell cortex and an apical pool of punctate actin which eventually matures into the characteristic apical actin network. We show that xNubp1 colocalizes with the apical actin network of multiciliated cells and that problems in basal body transport in xNubp1 morphants are associated with defects of the internal network of actin, while spacing and polarity issues are due to a failure of the apical and sub-apical actin pools to mature into a network. Effects of xNubp1 knockdown on the actin cytoskeleton are independent of RhoA localization and activation, suggesting that xNubp1 may have a direct role in the regulation of the actin cytoskeleton.


Subject(s)
Actin Cytoskeleton/physiology , Cilia/physiology , GTP-Binding Proteins/physiology , Morphogenesis , Xenopus Proteins/physiology , Xenopus laevis/embryology , Animals , Cell Movement , Female
16.
J Cell Biol ; 222(11)2023 11 06.
Article in English | MEDLINE | ID: mdl-37851005

ABSTRACT

The c-Jun N-terminal kinase (JNK) regulates various important physiological processes. Although the JNK pathway has been under intense investigation for over 20 yr, its complexity is still perplexing, with multiple protein partners underlying the diversity of its activity. We show that JNK is associated with the basal bodies in both primary and motile cilia. Loss of JNK disrupts basal body migration and docking and leads to severe ciliogenesis defects. JNK's involvement in ciliogenesis stems from a dual role in the regulation of the actin networks of multiciliated cells (MCCs) and the establishment of the intraflagellar transport-B core complex. JNK signaling is also critical for the maintenance of the actin networks and ciliary function in mature MCCs. JNK is implicated in the development of diabetes, neurodegeneration, and liver disease, all of which have been linked to ciliary dysfunction. Our work uncovers a novel role of JNK in ciliogenesis and ciliary function that could have important implications for JNK's role in the disease.


Subject(s)
Actins , JNK Mitogen-Activated Protein Kinases , MAP Kinase Signaling System , Actins/genetics , Actins/metabolism , Cilia/metabolism , Phosphorylation , Protein Processing, Post-Translational
17.
Breast Cancer Res Treat ; 134(1): 353-62, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22434525

ABSTRACT

In spite the close association of the triple-negative breast cancer immunophenotype with hereditary breast cancers and the BRCA1 pathway, there is a lack of population studies that determine the frequency of BRCA1 mutations among triple-negative breast cancer patients. To address this, we have screened a large sample of 403 women diagnosed with triple-negative invasive breast cancer, independently of their age or family history, for germline BRCA1 mutations. Median age at diagnosis was 50 years (range 20-83). The overall prevalence of triple-negative cases among the initial patient group with invasive breast cancer was 8%. BRCA1 was screened by direct DNA sequencing in all patients, including all exons where a mutation was previously found in the Greek population (exons 5, 11, 12, 16, 20, 21, 22, 23, 24-77% of the BRCA1 coding region), including diagnostic PCRs to detect the three Greek founder large genomic rearrangements. Sixty-five deleterious BRCA1 mutations were identified among the 403 triple-negative breast cancer patients (16%). Median age of onset for mutation carriers was 39 years. Among a total of 106 women with early-onset triple-negative breast cancer (<40 years), 38 (36%) had a BRCA1 mutation, while 27% of women with triple-negative breast cancer diagnosed before 50 years (56/208) had a BRCA1 mutation. A mutation was found in 48% (50/105) of the triple-negative breast cancer patients with family history of breast or ovarian cancer. It is noteworthy, however, that of the 65 carriers, 15 (23%) had no reported family history of related cancers. All but one of the carriers had grade III tumors (98%). These results indicate that women with early-onset triple-negative breast cancer, and ideally all triple-negative breast cancer patients, are candidates for BRCA1 genetic testing even in the absence of a family history of breast or ovarian cancer.


Subject(s)
BRCA1 Protein/genetics , Carcinoma, Ductal, Breast/genetics , Carcinoma, Lobular/genetics , Genetic Testing , Hereditary Breast and Ovarian Cancer Syndrome/genetics , Adult , Aged , Aged, 80 and over , Carcinoma, Ductal, Breast/diagnosis , Carcinoma, Ductal, Breast/epidemiology , Carcinoma, Ductal, Breast/metabolism , Carcinoma, Lobular/diagnosis , Carcinoma, Lobular/epidemiology , Carcinoma, Lobular/metabolism , DNA Mutational Analysis , Female , Hereditary Breast and Ovarian Cancer Syndrome/diagnosis , Hereditary Breast and Ovarian Cancer Syndrome/epidemiology , Hereditary Breast and Ovarian Cancer Syndrome/metabolism , Heterozygote , Humans , Middle Aged , Mutation , Patient Selection , Prevalence , Receptor, ErbB-2/metabolism , Receptors, Estrogen/metabolism , Receptors, Progesterone/metabolism , Young Adult
18.
BMC Cancer ; 12: 342, 2012 Aug 06.
Article in English | MEDLINE | ID: mdl-22866924

ABSTRACT

BACKGROUND: BRCA1 (B), ERCC1 (E), RRM1 (R) and TYMS (T) mRNA expression has been extensively studied with respect to NSCLC patient outcome upon various chemotherapy agents. However, these markers have not been introduced into clinical practice yet. One of the reasons seems to be lack of a standard approach for the classification of the reported high/low mRNA expression. The aim of this study was to determine the prognostic/predictive impact of B, E, R, T in routinely-treated NSCLC patients by taking into account the expression of these genes in the normal lung parenchyma. METHODS: B, E, R, T mRNA expression was examined in 276 NSCLC samples (real-time PCR). The normal range of B, E, R, T transcript levels was first determined in matched tumor - normal pairs and then applied to the entire tumor series. Four main chemotherapy categories were examined: taxanes-without-platinum (Tax); platinum-without-taxanes (Plat); taxanes/platinum doublets (Tax/Plat); and, all-other combinations. RESULTS: In comparison to remotely located normal lung parenchyma, B, E, R, T mRNA expression was generally increased in matched tumors, as well as in the entire tumor series. Therefore, tumors were classified as expressing normal or aberrant B, E, R, T mRNA. In general, no marker was associated with overall and progression free survival (OS, PFS). Upon multivariate analysis, aberrant intratumoral TYMS predicted for shorter PFS than normal TYMS in 1st line chemo-naïve treated patients (p = 0.012). In the same setting, specific interactions were observed for aberrant TYMS with Plat and Tax/Plat (p = 0.003 and p = 0.006, respectively). Corresponding patients had longer PFS in comparison to those treated with Tax (Plat: HR = 0.234, 95% CI:0.108-0.506, Wald's p < 0.0001; Tax/Plat: HR = 0.242, 95% CI:0.131-0.447, Wald's p < 0.0001). Similar results were obtained for PFS in 1st line chemo-naïve and (neo)adjuvant pre-treated patients. Adenocarcinoma, early disease stage, and treatment with Tax/Plat doublets independently predicted for prolonged OS in patients who received only one line of treatment (adjuvant or 1st line). CONCLUSION: Classifying intratumoral B, E, R, T mRNA expression in comparison to normal lung may facilitate standardization of these parameters for prospective studies. With this approach, NSCLC patients with aberrant intratumoral TYMS expression will probably fare better with platinum-based treatments.


Subject(s)
Biomarkers, Tumor/metabolism , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , DNA Repair/genetics , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Thymidylate Synthase/genetics , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , BRCA1 Protein/biosynthesis , BRCA1 Protein/genetics , BRCA1 Protein/metabolism , Biomarkers, Tumor/biosynthesis , Biomarkers, Tumor/genetics , Carcinoma, Non-Small-Cell Lung/drug therapy , Carcinoma, Non-Small-Cell Lung/enzymology , Cohort Studies , DNA-Binding Proteins/biosynthesis , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Endonucleases/biosynthesis , Endonucleases/genetics , Endonucleases/metabolism , Female , Gene Expression Profiling , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/enzymology , Male , Middle Aged , Multivariate Analysis , Organoplatinum Compounds/administration & dosage , Organoplatinum Compounds/therapeutic use , RNA, Messenger/biosynthesis , RNA, Messenger/genetics , RNA, Messenger/metabolism , Ribonucleoside Diphosphate Reductase , Survival Analysis , Taxoids/administration & dosage , Taxoids/therapeutic use , Thymidylate Synthase/metabolism , Treatment Outcome , Tumor Suppressor Proteins/biosynthesis , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolism
19.
J Biomed Biotechnol ; 2012: 627602, 2012.
Article in English | MEDLINE | ID: mdl-22287835

ABSTRACT

The photostability and narrow emission spectra of nanometer-scale semiconductor crystallites (QDs) make them desirable candidates for whole-mount fluorescent in situ hybridization to detect mRNA transcripts in morphologically preserved intact embryos. We describe a method for direct QD labeling of modified oligonucleotide probes through streptavidin-biotin and antibody-mediated interactions (anti-FITC and anti-digoxigenin). To overcome permeability issues and allow QD conjugate penetration, embryos were treated with proteinase K. The use of QDs dramatically increased sensitivity of whole-mount in situ hybridization (WISH) in comparison with organic fluorophores and enabled fluorescent detection of specific transcripts within cells without the use of enzymatic amplification. Therefore, this method offers significant advantages both in terms of sensitivity, as well as resolution. Specifically, the use of QDs alleviates issues of photostability and limited brightness plaguing organic fluorophores and allows fluorescent imaging of cleared embryos. It also offers new imaging possibilities, including intracellular localization of mRNAs, simultaneous multiple-transcript detection, and visualization of mRNA expression patterns in 3D.


Subject(s)
In Situ Hybridization, Fluorescence/methods , Nanoparticles/chemistry , Quantum Dots , RNA, Messenger/analysis , Xenopus/embryology , Animals , Endopeptidase K/chemistry , Fluorescent Dyes/chemistry , Gene Expression Profiling , Permeability , Xenopus/genetics , Xenopus/metabolism
20.
Biomed Chromatogr ; 26(4): 534-40, 2012 Apr.
Article in English | MEDLINE | ID: mdl-21989922

ABSTRACT

A quantitative method, using LC/ESI-MS(n) with a quadrupole linear ion trap mass analyzer, has been developed for the analysis of ipratropium cation in horse plasma and urine. The method applies solid-phase extraction with WCX cartridges for plasma and MM2 cartridges for urine, prior to analysis by LC/ESI-MS(n). The efficiency of extraction combined with the sensitivity and the selectivity of MS(n) allows for the quantification of ipratropium cation at picogram per milliliter levels. The analytical capabilities of the method have been successfully checked by the quantitative analysis of ipratropium cation in post-administration samples collected from horses treated by nebulization.


Subject(s)
Cholinergic Antagonists/blood , Cholinergic Antagonists/urine , Chromatography, High Pressure Liquid/methods , Horses/blood , Horses/urine , Ipratropium/blood , Ipratropium/urine , Animals , Sensitivity and Specificity , Solid Phase Extraction/methods , Spectrometry, Mass, Electrospray Ionization/methods
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