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1.
PLoS Negl Trop Dis ; 18(4): e0012057, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38557658

ABSTRACT

BACKGROUND: Intraspecific variations in snake venom composition have been extensively documented, contributing to the diverse clinical effects observed in envenomed patients. Understanding these variations is essential for developing effective snakebite management strategies and targeted antivenom therapies. We aimed to comprehensively investigate venoms from three distinct populations of N. mossambica from Eswatini, Limpopo, and KwaZulu-Natal regions in Africa in terms of their protein composition and reactivity with three commercial antivenoms (SAIMR polyvalent, EchiTAb+ICP, and Antivipmyn Africa). METHODOLOGY/PRINCIPAL FINDINGS: Naja mossambica venoms from Eswatini region exhibited the highest content of neurotoxic proteins, constituting 20.70% of all venom proteins, compared to Limpopo (13.91%) and KwaZulu-Natal (12.80%), and was characterized by the highest diversity of neurotoxic proteins, including neurotoxic 3FTxs, Kunitz-type inhibitors, vespryns, and mamba intestinal toxin 1. KwaZulu-Natal population exhibited considerably lower cytotoxic 3FTx, higher PLA2 content, and significant diversity in low-abundant proteins. Conversely, Limpopo venoms demonstrated the least diversity as demonstrated by electrophoretic and mass spectrometry analyses. Immunochemical assessments unveiled differences in venom-antivenom reactivity, particularly concerning low-abundance proteins. EchiTAb+ICP antivenom demonstrated superior reactivity in serial dilution ELISA assays compared to SAIMR polyvalent. CONCLUSIONS/SIGNIFICANCE: Our findings reveal a substantial presence of neurotoxic proteins in N. mossambica venoms, challenging previous understandings of their composition. Additionally, the detection of numerous peptides aligning to uncharacterized proteins or proteins with unknown functions underscores a critical issue with existing venom protein databases, emphasizing the substantial gaps in our knowledge of snake venom protein components. This underscores the need for enhanced research in this domain. Moreover, our in vitro immunological assays suggest EchiTAb+ICP's potential as an alternative to SAIMR antivenom, requiring confirmation through prospective in vivo neutralization studies.


Subject(s)
Antivenins , Naja , Animals , Humans , Antivenins/pharmacology , Naja/metabolism , Proteomics , Prospective Studies , South Africa , Elapid Venoms/toxicity , Proteins
3.
Toxins (Basel) ; 14(4)2022 04 16.
Article in English | MEDLINE | ID: mdl-35448894

ABSTRACT

Antivenom immunotherapy is the mainstay of treatment for snakebite envenoming. Most parts of the world affected by snakebite envenoming depend on broad-spectrum polyspecific antivenoms that are known to contain a low content of case-specific efficacious immunoglobulins. Thus, advances in toxin-specific antibodies production hold much promise in future therapeutic strategies of snakebite envenoming. We report anti-3FTxs monoclonal antibodies developed against N. ashei venom in mice. All the three test mAbs (P4G6a, P6D9a, and P6D9b) were found to be IgG antibodies, isotyped as IgG1. SDS-PAGE analysis of the test mAbs showed two major bands at approximately 55 and 29 kDa, suggestive of immunoglobulin heavy and light chain composition, respectively. The immunoaffinity-purified test mAbs demonstrated higher binding efficacy to the target antigen compared to negative control. Similarly, a cocktail of the test mAbs was found to induce a significantly higher inhibition (p-value < 0.0001) compared to two leading commercial brands of antivenoms on the Kenyan market, implying a higher specificity for the target antigen. Both the test mAbs and 3FTxs polyclonal antibodies induced comparable inhibition (p-value = 0.9029). The inhibition induced by the 3FTxs polyclonal antibodies was significantly different from the two antivenoms (p-value < 0.0001). Our results demonstrate the prospects of developing toxin-specific monoclonal-based antivenoms for snakebite immunotherapy.


Subject(s)
Antineoplastic Agents, Immunological , Snake Bites , Animals , Antibodies, Monoclonal/pharmacology , Antivenins/therapeutic use , Elapid Venoms , Immunoglobulin G , Kenya , Mice , Naja/metabolism , Snake Bites/drug therapy , Three Finger Toxins
4.
Molecules ; 27(3)2022 Jan 28.
Article in English | MEDLINE | ID: mdl-35164152

ABSTRACT

The administration of toxin-specific therapy in snake envenoming is predicated on improved diagnostic techniques capable of detecting specific venom toxins. Various serological tests have been used in detecting snakebite envenoming. Comparatively, enzyme-linked immunosorbent assay (ELISA) has been shown to offer a wider practical application. We report an inhibition ELISA for detecting three-finger toxin (3FTx) proteins in venoms of African spitting cobras. The optimized assay detected 3FTxs in N. ashei (including other Naja sp.) venoms, spiked samples, and venom-challenged mice samples. In venoms of Naja sp., the assay showed inhibition, implying the detection of 3FTxs, but showed little or no inhibition in non-Naja sp. In mice-spiked samples, one-way ANOVA results showed that the observed inhibition was not statistically significant between spiked samples and negative control (p-value = 0.164). Similarly, the observed differences in inhibition between venom-challenged and negative control samples were not statistically significant (p-value = 0.9109). At an LOD of 0.01 µg/mL, the assay was able to confirm the presence of 3FTxs in the samples. Our results show a proof of concept for the use of an inhibition ELISA model as a tool for detecting 3FTxs in the venoms of African spitting cobra snakes.


Subject(s)
Elapid Venoms/analysis , Enzyme-Linked Immunosorbent Assay/methods , Three Finger Toxins/analysis , Analysis of Variance , Animals , Elapidae , Female , Mice , Mice, Inbred BALB C
5.
Toxins (Basel) ; 12(8)2020 08 04.
Article in English | MEDLINE | ID: mdl-32759763

ABSTRACT

In contrast to comprehensively investigated antibacterial activity of snake venoms, namely crude venoms and their selected components, little is known about antifungal properties of elapid snake venoms. In the present study, the proteome of two venoms of red spitting cobra Naja pallida (NPV) and Mozambique spitting cobra Naja mossambica (NMV) was characterized using LC-MS/MS approach, and the antifungal activity of crude venoms against three Candida species was established. A complex response to venom treatment was revealed. NPV and NMV, when used at relatively high concentrations, decreased cell viability of C. albicans and C. tropicalis, affected cell cycle of C. albicans, inhibited C. tropicalis-based biofilm formation and promoted oxidative stress in C. albicans, C. glabrata and C. tropicalis cells. NPV and NMV also modulated ammonia pulses during colony development and aging in three Candida species. All these observations provide evidence that NPV and NMV may diminish selected pathogenic features of Candida species. However, NPV and NMV also promoted the secretion of extracellular phospholipases that may facilitate Candida pathogenicity and limit their usefulness as anti-candidal agents. In conclusion, antifungal activity of snake venoms should be studied with great caution and a plethora of pathogenic biomarkers should be considered in the future experiments.


Subject(s)
Antifungal Agents/pharmacology , Candida/drug effects , Elapid Venoms/pharmacology , Naja , Animals , Biofilms/drug effects , Candida/physiology , Cell Cycle/drug effects , Elapid Venoms/chemistry , Mitochondria/drug effects , Mitochondria/metabolism , Proteome/analysis , Reactive Oxygen Species/metabolism , Reptilian Proteins/analysis
6.
Animals (Basel) ; 10(3)2020 Mar 08.
Article in English | MEDLINE | ID: mdl-32182656

ABSTRACT

Snake venom is an extremely interesting natural mixture of proteins and peptides, characterized by both high diversity and high pharmacological potential. Much attention has been paid to the study of venom composition of different species and also detailed analysis of the properties of individual components. Since proteins and peptides are the active ingredients in venom, rapidly developing proteomic techniques are used to analyze them. During such analyses, one of the routine operations is to measure the protein concentration in the sample. The aim of this study was to compare five methods used to measure protein content in venoms of two snake species: the Viperids representative, Agkistrodon contortrix, and the Elapids representative, Naja ashei. The study showed that for A. contortrix venom, the concentration of venom protein measured by four methods is very similar and only the NanoDrop method clearly stands out from the rest. However, in the case of N. ashei venom, each technique yields significantly different results. We hope that this report will help to draw attention to the problem of measuring protein concentration, especially in such a complex mixture as animal venoms.

7.
Molecules ; 25(2)2020 Jan 10.
Article in English | MEDLINE | ID: mdl-31936872

ABSTRACT

One of the key problems of modern infectious disease medicine is the growing number of drug-resistant and multi-drug-resistant bacterial strains. For this reason, many studies are devoted to the search for highly active antimicrobial substances that could be used in therapy against bacterial infections. As it turns out, snake venoms are a rich source of proteins that exert a strong antibacterial effect, and therefore they have become an interesting research material. We analyzed Naja ashei venom for such antibacterial properties, and we found that a specific composition of proteins can act to eliminate individual bacterial cells, as well as the entire biofilm of Staphylococcus epidermidis. In general, we used ion exchange chromatography (IEX) to obtain 10 protein fractions with different levels of complexity, which were then tested against certified and clinical strains of S. epidermidis. One of the fractions (F2) showed exceptional antimicrobial effects both alone and in combination with antibiotics. The protein composition of the obtained fractions was determined using mass spectrometry techniques, indicating a high proportion of phospholipases A2, three-finger toxins, and L-amino acids oxidases in F2 fraction, which are most likely responsible for the unique properties of this fraction. Moreover, we were able to identify a new group of low abundant proteins containing the Ig-like domain that have not been previously described in snake venoms.


Subject(s)
Anti-Bacterial Agents , Biofilms/drug effects , Elapid Venoms , Naja , Staphylococcus epidermidis/physiology , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Biofilms/growth & development , Elapid Venoms/chemistry , Elapid Venoms/pharmacology
8.
Lancet ; 395(10219): 200-211, 2020 01 18.
Article in English | MEDLINE | ID: mdl-31954465

ABSTRACT

BACKGROUND: Sepsis is life-threatening organ dysfunction due to a dysregulated host response to infection. It is considered a major cause of health loss, but data for the global burden of sepsis are limited. As a syndrome caused by underlying infection, sepsis is not part of standard Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) estimates. Accurate estimates are important to inform and monitor health policy interventions, allocation of resources, and clinical treatment initiatives. We estimated the global, regional, and national incidence of sepsis and mortality from this disorder using data from GBD 2017. METHODS: We used multiple cause-of-death data from 109 million individual death records to calculate mortality related to sepsis among each of the 282 underlying causes of death in GBD 2017. The percentage of sepsis-related deaths by underlying GBD cause in each location worldwide was modelled using mixed-effects linear regression. Sepsis-related mortality for each age group, sex, location, GBD cause, and year (1990-2017) was estimated by applying modelled cause-specific fractions to GBD 2017 cause-of-death estimates. We used data for 8·7 million individual hospital records to calculate in-hospital sepsis-associated case-fatality, stratified by underlying GBD cause. In-hospital sepsis-associated case-fatality was modelled for each location using linear regression, and sepsis incidence was estimated by applying modelled case-fatality to sepsis-related mortality estimates. FINDINGS: In 2017, an estimated 48·9 million (95% uncertainty interval [UI] 38·9-62·9) incident cases of sepsis were recorded worldwide and 11·0 million (10·1-12·0) sepsis-related deaths were reported, representing 19·7% (18·2-21·4) of all global deaths. Age-standardised sepsis incidence fell by 37·0% (95% UI 11·8-54·5) and mortality decreased by 52·8% (47·7-57·5) from 1990 to 2017. Sepsis incidence and mortality varied substantially across regions, with the highest burden in sub-Saharan Africa, Oceania, south Asia, east Asia, and southeast Asia. INTERPRETATION: Despite declining age-standardised incidence and mortality, sepsis remains a major cause of health loss worldwide and has an especially high health-related burden in sub-Saharan Africa. FUNDING: The Bill & Melinda Gates Foundation, the National Institutes of Health, the University of Pittsburgh, the British Columbia Children's Hospital Foundation, the Wellcome Trust, and the Fleming Fund.


Subject(s)
Global Burden of Disease/statistics & numerical data , Sepsis/epidemiology , Sepsis/mortality , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Cause of Death , Child , Child, Preschool , Female , Humans , Incidence , Infant , Infant, Newborn , Male , Middle Aged , Sex Distribution , Socioeconomic Factors , Young Adult
9.
Nervenarzt ; 90(3): 243-250, 2019 Mar.
Article in German | MEDLINE | ID: mdl-30643954

ABSTRACT

BACKGROUND: Motherhood in adolescence is associated with risks for both the young mother and the children. OBJECTIVE: Presentation of the current state of research on the mental health of adolescent mothers and its effects on the development of their children. MATERIAL AND METHODS: Electronic database search in PubMed using various combined key terms such as "teenage pregnancy", "adolescent pregnancy", "teenage mother", "child development", "mother-child interaction". Review of the literature of the sources found and discussion of current publications and databases of public institutions. RESULTS: In addition to psychosocial risks such as fewer education years due to family formation and lower incomes, young mothers also suffer more frequently from mental disorders, both before pregnancy and due to the additional burden of motherhood in their own developmental phase of youth. These can have unfavorable effects on the mother-child interaction and on the psychosocial and cognitive development of the children, thereby leading to the transgenerational transmission of risk factors. CONCLUSION: In addition to primary prevention by avoiding teenage pregnancies, early identification of adolescent mothers and children at risk for early treatment and intervention is necessary.


Subject(s)
Mental Health , Mothers , Pregnancy in Adolescence , Adolescent , Child , Child Development , Female , Humans , Mother-Child Relations/psychology , Mothers/psychology , Pregnancy , Pregnancy in Adolescence/psychology , Socioeconomic Factors
10.
J Cell Physiol ; 234(5): 6147-6160, 2019 05.
Article in English | MEDLINE | ID: mdl-30317566

ABSTRACT

Snake venoms are widely studied in terms of their systemic toxicity and proteolytic, hemotoxic, neurotoxic, and cytotoxic activities. However, little is known about snake-venom-mediated effects when used at low, noncytotoxic concentrations. In the current study, two human fibroblast cell lines of different origin, namely WI-38 fetal lung fibroblasts and BJ foreskin fibroblasts were used to investigate snake-venom-induced adaptive response at a relatively noncytotoxic concentration (0.01 µg/ml). The venoms of Indochinese spitting cobra ( Naja siamensis), western green mamba ( Dendroaspis viridis), forest cobra ( Naja melanoleuca), and southern copperhead ( Agkistrodon contortrix) were considered. Snake venoms promoted FOXO3a-mediated oxidative stress response and to a lesser extent DNA damage response, which lead to changes in cell cycle regulators both at messenger RNA and protein levels, limited cell proliferation and migration, and induced cellular senescence. Taken together, we have shown for the first time that selected snake venoms may also exert adverse effects when used at relatively noncytotoxic concentrations.


Subject(s)
Cellular Senescence/drug effects , Fibroblasts/drug effects , Oxidative Stress/drug effects , Snake Venoms/pharmacology , Animals , Cell Movement/drug effects , Cell Proliferation/drug effects , DNA Damage/drug effects , Gene Expression Regulation/drug effects , Humans
11.
J Exp Bot ; 2018 Apr 26.
Article in English | MEDLINE | ID: mdl-29701811

ABSTRACT

Changes in cytosolic Ca2+ concentration ([Ca2+]cyt) serve to transmit information in eukaryotic cells. The involvement of this second messenger in plant cell growth as well as osmotic- and water relations is well established. After almost 40 years of intense research on the coding and decoding of plant Ca2+ signals, numerous proteins involved in Ca2+ action have been identified. However, we are still far from understanding the complexity of Ca2+ networks. New in vivo Ca2+ imaging techniques combined with molecular genetics allow visualisation of spatio-temporal aspects of Ca2+ signalling. In parallel, cell biology together with protein biochemistry and electrophysiology are able to dissect information processing by this second messenger in space and time. Here we focus on the time-resolved changes in cellular events upon Ca2+ signals, concentrating on the two best-studied cell types, pollen tubes and guard cells. We put their signalling networks side by side, compare them with those of other cell types and discuss rapid signalling in the context of Ca2+ transients and oscillations to regulate ion homeostasis.

12.
J Diabetes Res ; 2017: 8615769, 2017.
Article in English | MEDLINE | ID: mdl-29238730

ABSTRACT

BACKGROUND: In T1DM, delayed pubertal development and reduced final height are associated with inadequate metabolic control. OBJECTIVE: To assess whether T1DM affects pubertal growth spurt and whether metabolic control during puberty is gender-related. METHODS: Using a large multicentre database, longitudinal data from 1294 patients were analysed. Inclusion criteria: complete records of height and HbA1c from the age of seven to 16 years. Exclusion criteria: other significant chronic diseases and medications, T1DM duration less than three months, and initial BMI < 3rd or >97th percentile. RESULTS: Growth velocity (GV) was impaired with a significant reduction of peak GV by 1.2 cm in boys. HbA1c increase during male puberty was lower except for a period of 1.5 years. The highest HbA1c increase in boys coincided with maximum growth spurt. In girls, the highest HbA1c increase was observed during late puberty. Even though there is impaired GV, both sexes reach a height at 16 years of age which corresponds to the background population height. CONCLUSION: Worsening of metabolic control is sex-discordant and associated with gender-specific alterations of GV. However, the vast majority of boys and girls with T1DM seems to reach normal height at the age of 16 years.


Subject(s)
Diabetes Mellitus, Type 1/metabolism , Puberty/metabolism , Adolescent , Child , Databases, Factual , Female , Glycated Hemoglobin/analysis , Humans , Male , Sex Factors
13.
Neuroimage Clin ; 14: 112-121, 2017.
Article in English | MEDLINE | ID: mdl-28180069

ABSTRACT

Behavioral research has revealed deficits in the development of joint attention (JA) as one of the earliest signs of autism. While the neural basis of JA has been studied predominantly in adults, we recently demonstrated a protracted development of the brain networks supporting JA in typically developing children and adolescents. The present eye-tracking/fMRI study now extends these findings to adolescents with autism. Our results show that in adolescents with autism JA is subserved by abnormal activation patterns in brain areas related to social cognition abnormalities which are at the core of ASD including the STS and TPJ, despite behavioral maturation with no behavioral differences. Furthermore, in the autism group we observed increased neural activity in a network of social and emotional processing areas during interactions with their mother. Moreover, data indicated that less severely affected individuals with autism showed higher frontal activation associated with self-initiated interactions. Taken together, this study provides first-time data of JA in children/adolescents with autism incorporating the interactive character of JA, its reciprocity and motivational aspects. The observed functional differences in adolescents ASD suggest that persistent developmental differences in the neural processes underlying JA contribute to social interaction difficulties in ASD.


Subject(s)
Attention Deficit Disorder with Hyperactivity/etiology , Autistic Disorder , Fixation, Ocular/physiology , Interpersonal Relations , Magnetic Resonance Imaging , Social Behavior , Adolescent , Autistic Disorder/complications , Autistic Disorder/diagnostic imaging , Autistic Disorder/psychology , Brain Mapping , Child , Female , Humans , Image Processing, Computer-Assisted , Male , Oxygen/blood , Statistics, Nonparametric
14.
Hum Brain Mapp ; 38(2): 855-868, 2017 02.
Article in English | MEDLINE | ID: mdl-27774721

ABSTRACT

Childhood maltreatment is associated with alterations in neural architecture that potentially put these children at increased risk for psychopathology. Alterations in white matter (WM) tracts have been reported, however no study to date has investigated WM connectivity in brain networks in maltreated children to quantify global and local abnormalities through graph theoretical analyses of DTI data. We aimed for a multilevel investigation examining the DTI-based structural connectome and its associations with basal cortisol levels of 25 children with documented maltreatment experiences before age 3, and 24 matched controls (age: 10.6 ± 1.75 years). On the global and lobar level, maltreated children showed significant reductions in global connectivity strength, local connectivity and increased path length, suggesting deviations from the small-world network architecture previously associated with psychopathology. Reductions in global connectivity were associated with placement instability, attenuated cortisol secretion and higher levels of internalizing and externalizing behaviours. Regional measures revealed lower connectivity strength especially in regions within the ventromedial prefrontal cortex (vMPFC) in maltreated children. These findings show that childhood maltreatment is associated with systemic global neurodevelopmental alterations in WM networks next to regional alterations in areas involved in the regulation of affect. These alterations in WM organization could underlie global functional deficits and multi-symptom patterns frequently observed in children with maltreatment experiences. Hum Brain Mapp 38:855-868, 2017. © 2016 Wiley Periodicals, Inc.


Subject(s)
Brain/diagnostic imaging , Child Abuse , Diffusion Tensor Imaging , Mental Disorders/diagnostic imaging , Neural Pathways/diagnostic imaging , White Matter/diagnostic imaging , Adolescent , Brain Mapping , Child , Child Abuse/psychology , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Mental Disorders/etiology , Models, Neurological , Nerve Fibers, Myelinated/physiology , Psychiatric Status Rating Scales
15.
Klin Padiatr ; 228(6-07): 307-312, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27846660

ABSTRACT

Background: Diabetes mellitus is a common endocrinopathy in patients with thalassemia major, but the occurrence of hemoglobinopathies is rare in Germany and Western Europe. The longitudinal German-Austrian DPV (Diabetes Patienten Verlaufsdokumentation) registry allows a comprehensive characterization of this group of patients. Patients/methods: Patients from the DPV-registry aged<30 years with thalassemia major or other hemoglobinopathies were compared to patients with type 1 diabetes (T1D) and type 2 diabetes (T2D) using the statistical software SAS 9.4. Results: 94 patients (0.13% of patients) with hemoglobinopathies are registered in DPV. 82.4% of 17 patients with thalassemia major, 100% of 12 patients with sickle cell disease (SCD) and >90% of 65 patients with other hemoglobinopathies receive insulin treatment. In the majority of patients with thalassemia major, hemosiderosis is documented. Patients with thalassemia major developed diabetes at a median age of 14.6 [IQR 8.4-18.0] years (9.0 years [5.3-12.5] in T1D; 18.7 years [14.2-25.6] in TD2; both p<0.01). They show high HbA1c/fructosamine levels and frequent hypoglycemia, reflecting poor metabolic control. Conclusion: Diabetes in thalassemia major is probably caused by hemosiderosis due to polytransfusion, while patients with SCD/thalassemia minor are most likely affected by T1D. The high rate of hypoglycemia in patients with ß-thalassemia major may be caused by liver fibrosis and a lack of hepatic glycogen stores.


Subject(s)
Diabetes Mellitus, Type 1/epidemiology , Diabetes Mellitus, Type 2/epidemiology , Hemoglobinopathies/epidemiology , beta-Thalassemia/epidemiology , Adolescent , Adult , Age of Onset , Comorbidity , Cross-Sectional Studies , Diabetes Complications/epidemiology , Female , Humans , Male , Registries , Young Adult
16.
J Neural Transm (Vienna) ; 123(8): 949-59, 2016 08.
Article in English | MEDLINE | ID: mdl-27188331

ABSTRACT

Gray matter (GM) and white matter (WM) volume loss occur in the brains of patients with acute anorexia nervosa (AN) and improve again upon weight restoration. Adolescence is an important time period for AN to begin. However, little is known about the differences between brain changes in adolescents vs adults. We used a meta-analysis and a qualitative review of all MRI studies regarding acute structural brain volume changes and their recovery in adolescents and adults with AN. 29 studies with 473 acute, 121 short-term weight-recovered and 255 long-term recovered patients with AN were included in the meta-analysis. In acute AN, GM and WM were reduced compared to healthy controls. Acute adolescent patients showed a significantly greater GM reduction than adults (-8.4 vs -3.1 %), the difference in WM (-4.0 vs -2.1 %) did not reach significance. Short-term weight-recovered patients showed a remaining GM deficit of 3.6 % and a non-significant WM reduction of 0.9 % with no age differences. Following 1.5-8 years of remission, GM and WM were no longer significantly reduced in adults (GM -0.4 %, WM -0.7 %); long-term studies for adolescents were scarce. The qualitative review showed that GM volume loss was correlated with cognitive deficits and three studies found GM regions, cerebellar deficits and WM to be predictive of outcome. GM and WM are strongly reduced in acute AN and even more pronounced in adolescence. Long-term recovery appears to be complete for adults while no conclusions can be drawn for adolescents, thus caution remains.


Subject(s)
Anorexia Nervosa/diagnostic imaging , Brain Mapping , Brain/diagnostic imaging , Neuroimaging , Adolescent , Adult , Age Factors , Anorexia Nervosa/pathology , Humans , Young Adult
17.
Neuroimage ; 130: 248-260, 2016 Apr 15.
Article in English | MEDLINE | ID: mdl-26892856

ABSTRACT

Joint attention, the shared attentional focus of at least two people on a third significant object, is one of the earliest steps in social development and an essential aspect of reciprocal interaction. However, the neural basis of joint attention (JA) in the course of development is completely unknown. The present study made use of an interactive eye-tracking paradigm in order to examine the developmental trajectories of JA and the influence of a familiar interaction partner during the social encounter. Our results show that across children and adolescents JA elicits a similar network of "social brain" areas as well as attention and motor control associated areas as in adults. While other-initiated JA particularly recruited visual, attention and social processing areas, self-initiated JA specifically activated areas related to social cognition, decision-making, emotions and motivational/reward processes highlighting the rewarding character of self-initiated JA. Activation was further enhanced during self-initiated JA with a familiar interaction partner. With respect to developmental effects, activation of the precuneus declined from childhood to adolescence and additionally shifted from a general involvement in JA towards a more specific involvement for self-initiated JA. Similarly, the temporoparietal junction (TPJ) was broadly involved in JA in children and more specialized for self-initiated JA in adolescents. Taken together, this study provides first-time data on the developmental trajectories of JA and the effect of a familiar interaction partner incorporating the interactive character of JA, its reciprocity and motivational aspects.


Subject(s)
Attention/physiology , Brain Mapping/methods , Brain/physiology , Interpersonal Relations , Social Behavior , Adolescent , Child , Eye Movements , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Reward
18.
Amino Acids ; 48(4): 1109-1120, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26767373

ABSTRACT

The default mode network (DMN) plays a central role in intrinsic thought processes. Altered DMN connectivity has been linked to diminished cerebral serotonin synthesis. Diminished brain serotonin synthesis is further associated with a lack of impulse control and various psychiatric disorders. Here, we investigated the serotonergic modulation of intrinsic functional connectivity (FC) within the DMN in healthy adult females, controlling for the menstrual cycle phase. Eighteen healthy women in the follicular phase (aged 20-31 years) participated in a double-blind controlled cross-over study of serotonin depletion. Acute tryptophan depletion (ATD) and a balanced amino acid load (BAL), used as the control condition, were applied on two separate days of assessment. Neural resting state data using functional magnetic resonance imaging (fMRI) and individual trait impulsivity scores were obtained. ATD compared with BAL significantly reduced FC with the DMN in the precuneus (associated with self-referential thinking) and enhanced FC with the DMN in the frontal cortex (associated with cognitive reasoning). Connectivity differences with the DMN between BAL and ATD in the precentral gyrus were significantly correlated with the magnitude of serotonin depletion. Right medial frontal gyrus and left superior frontal gyrus connectivity differences with the DMN were inversely correlated with trait impulsivity. These findings partially deviate from previous findings obtained in males and underline the importance of gender-specific studies and controlling for menstrual cycle to further elucidate the mechanism of ATD-induced changes within intrinsic thought processes.


Subject(s)
Follicular Phase/physiology , Frontal Lobe/physiology , Nerve Net/physiology , Parietal Lobe/physiology , Rest/physiology , Serotonin/biosynthesis , Adult , Affect/drug effects , Affect/physiology , Amino Acids/administration & dosage , Brain Mapping , Cognition/drug effects , Cognition/physiology , Cross-Over Studies , Double-Blind Method , Female , Frontal Lobe/anatomy & histology , Frontal Lobe/drug effects , Humans , Impulsive Behavior/drug effects , Impulsive Behavior/physiology , Magnetic Resonance Imaging , Nerve Net/anatomy & histology , Nerve Net/drug effects , Parietal Lobe/anatomy & histology , Parietal Lobe/drug effects , Rest/psychology , Thinking/drug effects , Thinking/physiology , Tryptophan/administration & dosage , Tryptophan/deficiency
19.
Pediatr Diabetes ; 17(7): 483-491, 2016 11.
Article in English | MEDLINE | ID: mdl-26530288

ABSTRACT

BACKGROUND: Diabetes education of patients and/or parents is an essential part of diabetes care with effects on diabetes outcome. The objective of our study was to describe the current practice of diabetes education in Germany and Austria with regard to training frequency, patient age, migration background and diabetes therapy in a large cohort of pediatric patients with diabetes mellitus type 1 (T1DM). METHODS: We analyzed data from pediatric T1DM patients with diabetes training in 2013 and complete data available for treatment year in the multicenter Diabetes Patienten Verlaufsdokumentation (DPV) registry using sas 9.4. RESULTS: In 2013 21 871 pediatric patients with T1DM were documented [52.4% male, age: 12.70 (9.35-15.30) yr (median (interquartile range)], diabetes duration: 3.80 (1.45-7.00) yr, migration background: 21.4%, twice daily injections: 5.5%, multiple daily injections: 52.5%, insulin-pump therapy: 42%. Of these 32.31% were trained in 2013. Younger patients and their parents were trained more intensely and more frequently as inpatients compared with older patients (0-6 vs. 6-12 and 12-18 yr: teaching units: 13.07 vs. 12.05 and 9.79; inpatient: 79% vs. 72% and 70%). There was also a difference in training frequency with regard to migration background. Severe hypoglycemia or ketoacidosis resulted in intensification of training (4.0 vs. 2.0%; 7.8 vs. 3.1%). Centre-specific education tools were used frequently alone or in combination with published, standardized education programs. CONCLUSION: Training frequency was highest in younger patients and during the first year of diabetes. Acute complications resulted in more frequent diabetes training, indicating that currently many education sessions take place in consequence to these complications.


Subject(s)
Diabetes Mellitus, Type 1/therapy , Patient Education as Topic/methods , Patient Education as Topic/statistics & numerical data , Practice Patterns, Physicians'/statistics & numerical data , Adolescent , Austria/epidemiology , Child , Databases, Factual , Diabetes Complications/prevention & control , Diabetes Mellitus, Type 1/complications , Diabetes Mellitus, Type 1/epidemiology , Diabetic Ketoacidosis/epidemiology , Female , Germany/epidemiology , Humans , Hypertension/epidemiology , Male , Practice Patterns, Physicians'/trends , Registries
20.
Eur Neuropsychopharmacol ; 25(6): 846-56, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25869157

ABSTRACT

Diminished synthesis of the neurotransmitter serotonin (5-HT) has been linked to disrupted impulse control in aversive contexts. However, the neural correlates underlying a serotonergic modulation of female impulsivity remain unclear. The present study investigated punishment-induced inhibition in healthy young women. Eighteen healthy female subjects (aged 20-31) participated in a double-blinded, counterbalanced, placebo-controlled, within subjects, repeated measures study. They were assessed on two randomly assigned occasions that were controlled for menstrual cycle phase. In a randomized order, one day, acute tryptophan depletion (ATD) was used to reduce 5-HT synthesis in the brain. On the other day, participants received a tryptophan-balanced amino acid load (BAL) as a control condition. Three hours after administration of ATD/BAL, neural activity was recorded during a modified Go/No-Go task implementing reward or punishment processes using functional magnetic resonance imaging (fMRI). Neural activation during No-Go trials in punishment conditions after BAL versus ATD administration correlated positively with the magnitude of central 5-HT depletion in the ventral and subgenual anterior cingulate cortices (ACC). Furthermore, neural activation in the medial orbitofrontal cortex (mOFC) and the dorsal ACC correlated positively with trait impulsivity. The results indicate reduced neural sensitivity to punishment after short-term depletion of 5-HT in brain areas related to emotion regulation (subgenual ACC) increasing with depletion magnitude and in brain areas related to appraisal and expression of emotions (mOFC and dorsal ACC), increasing with trait impulsivity. This suggests a serotonergic modulation of neural circuits related to emotion regulation, impulsive behavior, and punishment processing in females.


Subject(s)
Gyrus Cinguli/physiology , Prefrontal Cortex/physiology , Punishment , Serotonin/deficiency , Adult , Decision Making/physiology , Double-Blind Method , Estradiol/blood , Female , Follicle Stimulating Hormone/blood , Gyrus Cinguli/blood supply , Humans , Impulsive Behavior/physiology , Luteinizing Hormone/blood , Neuropsychological Tests , Oxygen/blood , Prefrontal Cortex/blood supply , Psychiatric Status Rating Scales , Psychological Tests , Surveys and Questionnaires , Tryptophan/deficiency , Young Adult
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