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1.
Curr Biol ; 33(4): 749-754.e4, 2023 02 27.
Article in English | MEDLINE | ID: mdl-36638798

ABSTRACT

Understanding the impact of human disturbance on wildlife populations is of societal importance,1 with anthropogenic noise known to impact a range of taxa, including mammals,2 birds,3 fish,4 and invertebrates.5 While animals are known to use acoustic and other behavioral mechanisms to compensate for increasing noise at the individual level, our understanding of how noise impacts social animals working together remains limited. Here, we investigated the effect of noise on coordination between two bottlenose dolphins performing a cooperative task. We previously demonstrated that the dolphin dyad can use whistles to coordinate their behavior, working together with extreme precision.6 By equipping each dolphin with a sound-and-movement recording tag (DTAG-37) and exposing them to increasing levels of anthropogenic noise, we show that both dolphins nearly doubled their whistle durations and increased whistle amplitude in response to increasing noise. While these acoustic compensatory mechanisms are the same as those frequently used by wild cetaceans,8,9,10,11,12,13 they were insufficient to overcome the effect of noise on behavioral coordination. Indeed, cooperative task success decreased in the presence of noise, dropping from 85% during ambient noise control trials to 62.5% during the highest noise exposure. This is the first study to demonstrate in any non-human species that noise impairs communication between conspecifics performing a cooperative task. Cooperation facilitates vital functions across many taxa and our findings highlight the need to account for the impact of disturbance on functionally important group tasks in wild animal populations.


Subject(s)
Bottle-Nosed Dolphin , Animals , Bottle-Nosed Dolphin/physiology , Vocalization, Animal/physiology , Noise/adverse effects , Animals, Wild , Acoustics , Sound Spectrography
2.
Curr Biol ; 32(7): 1657-1663.e4, 2022 04 11.
Article in English | MEDLINE | ID: mdl-35334229

ABSTRACT

Vocal interactions are intrinsic features of social groups and can play a pivotal role in social bonding.1,2 Dunbar's social bonding hypothesis posits that vocal exchanges evolved to "groom at a distance" when social groups became too large or complex for individuals to devote time to physical bonding activities.1,3 Tests of this hypothesis in non-human primates, however, suggest that vocal exchanges occur between more strongly bonded individuals that engage in higher grooming rates4-7 and thus do not provide evidence for replacement of physical bonding. Here, we combine data on social bond strength, whistle exchange frequency, and affiliative contact behavior rates to test this hypothesis in wild male Indo-Pacific bottlenose dolphins, who form multi-level alliances that cooperate over access to females.8-10 We show that, although whistle exchanges are more likely to occur within the core alliance, they occur more frequently between those males that share weaker social bonds, i.e., between core allies that spend less time together, while the opposite occurs for affiliative physical contact behavior. This suggests that vocal exchanges function as a low-cost mechanism for male dolphins that spend less time in close proximity and engage in fewer affiliative contact behaviors to reinforce and maintain their valuable alliance relationships. Our findings provide new evidence outside of the primate lineage that vocal exchanges serve a bonding function and reveal that, as the social bonding hypothesis originally suggested, vocal exchanges can function as a replacement of physical bonding activities for individuals to maintain their important social relationships.


Subject(s)
Bottle-Nosed Dolphin , Vocalization, Animal , Animals , Female , Grooming , Interpersonal Relations , Male , Social Behavior
3.
Dev Child Welf ; 4(1): 3-19, 2022 Mar.
Article in English | MEDLINE | ID: mdl-38603085

ABSTRACT

Vital services provided by social workers to children in care or on the edge of care were largely delivered "online" during the COVID-19 pandemic. This paper explores the potential impact of these changes on vulnerable children and their families. Relationship-based practice is integral to social work and the shift to digital communication during the COVID-19 pandemic has led to accelerated practice changes and implications for relationship building both with and between service users. Going forward, social workers and other professionals are likely to move to an increasingly hybrid model of communication, combining both digital and face-to-face methods. This article identifies the impact of digital communication on relationships in professional practice, drawing on three studies of digital communication in the UK carried out at the University of East Anglia. The first considered how child protection social workers responded to the challenges of COVID-19, the second looked at how children in care were keeping in touch with their birth families and the third focused on the approaches being taken to moving children from foster care to adoptive families. Five themes related to relationships were identified across all three studies: the significance of the age and developmental stage of the child; the frequency of contact and communication; digital literacy/exclusion; the impact of the lack of sensory experience; and the importance of the relationship history. The article concludes with implications for utilising digital methods in building and maintaining relationships in practice and highlights the need to consider both the inner and outer worlds of those involved.

4.
Diabetes Obes Metab ; 20(11): 2557-2564, 2018 11.
Article in English | MEDLINE | ID: mdl-29892986

ABSTRACT

AIMS: Treatment with liraglutide 3.0 mg has been associated with gallbladder-related adverse events. To conduct a single-centre, double-blind, 12-week trial comparing the effect of 0.6 mg liraglutide and steady-state liraglutide 3.0 mg with placebo on gallbladder emptying in adults with body mass index (BMI) ≥27 kg/m2 and without diabetes. METHODS: Participants were randomized 1:1 to once-daily subcutaneous liraglutide (n = 26) or placebo (n = 26), starting at 0.6 mg with 0.6-mg weekly increments to 3.0 mg, with nutritional and physical activity counselling. A 600-kcal (23.7 g fat) liquid meal test was performed at baseline, after the first dose and after 12 weeks. The primary endpoint was the 12-week maximum postprandial gallbladder ejection fraction (GBEFmax ), measured over 240 minutes after starting the meal. RESULTS: Baseline characteristics were similar between groups (mean ± SD overall age 47.6 ± 10.0 years, BMI 32.6 ±3.4 kg/m2 , 50% women). Mean 12-week GBEFmax (treatment difference -3.7%, 95% confidence interval [CI] -13.1, 5.7) and area under the GBEF curve in the first 60 minutes (-390% × min, 95% CI -919, 140) did not differ for liraglutide 3.0 mg (n = 23) vs placebo (n = 24). The median (range) time to GBEFmax was 151 (11-240) minutes with liraglutide 3.0 mg and 77 (22-212) minutes with placebo. Similar findings were noted after the first 0.6-mg liraglutide dose. Gastrointestinal disorders, notably nausea and constipation, were the most frequently reported adverse events. CONCLUSIONS: Treatment with liraglutide did not affect the GBEFmax but appeared to prolong the time to GBEFmax .


Subject(s)
Gallbladder Emptying/drug effects , Liraglutide/pharmacology , Obesity/physiopathology , Overweight/physiopathology , Adolescent , Adult , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/drug therapy , Diabetes Mellitus, Type 2/metabolism , Diabetes Mellitus, Type 2/physiopathology , Double-Blind Method , Female , Humans , Liraglutide/therapeutic use , Male , Middle Aged , Obesity/complications , Obesity/metabolism , Overweight/complications , Overweight/metabolism , Placebos , Postprandial Period/drug effects , Young Adult
6.
Microb Ecol ; 69(4): 778-87, 2015 May.
Article in English | MEDLINE | ID: mdl-25403111

ABSTRACT

Nitrogen (N) fixation by N2-fixing bacteria (diazotrophs) is the primary N input to pristine ecosystems like boreal forests and subarctic and arctic tundra. However, the contribution by the various diazotrophs to habitat N2 fixation remains unclear. We present results from in situ assessments of N2 fixation of five diazotroph associations (with a legume, lichen, feather moss, Sphagnum moss and free-living) incorporating the ground cover of the associations in five typical habitats in the subarctic (wet and dry heath, polygon-heath, birch forest, mire). Further, we assessed the importance of soil and air temperature, as well as moisture conditions for N2 fixation. Across the growing season, the legume had the highest total as well as the highest fraction of N2 fixation rates at habitat level in the heaths (>85 % of habitat N2 fixation), whereas the free-living diazotrophs had the highest N2 fixation rates in the polygon heath (56 %), the lichen in the birch forest (87 %) and Sphagnum in the mire (100 %). The feather moss did not contribute more than 15 % to habitat N2 fixation in any of the habitats despite its high ground cover. Moisture content seemed to be a major driver of N2 fixation in the lichen, feather moss and free-living diazotrophs. Our results show that the range of N2 fixers found in pristine habitats contribute differently to habitat N2 fixation and that ground cover of the associates does not necessarily mirror contribution.


Subject(s)
Bacteria/metabolism , Ecosystem , Embryophyta/metabolism , Lichens/metabolism , Nitrogen Fixation , Soil Microbiology , Embryophyta/microbiology , Lichens/microbiology , Soil/chemistry , Sweden , Taiga , Wetlands
7.
BMC Pregnancy Childbirth ; 14: 419, 2014 Dec 19.
Article in English | MEDLINE | ID: mdl-25524498

ABSTRACT

BACKGROUND: The circumstances under which women obtain unsafe abortion vary and depend on the traditional methods known and the type of providers present. In rural Tanzania women often resort to traditional providers who use plant species as abortion remedies. Little is known about how these plants are used and their potential effect. METHODS: Data were obtained among women admitted with incomplete abortion at Kagera Regional Hospital during the period January - June, 2006. The women underwent an empathetic interview to determine if they had experienced an unsafe abortion prior to their admission. In all 125/187 women revealed having had an unsafe abortion. The women identified as having had an unsafe abortion underwent a questionnaire interview where information about abortion provider and abortion method used was obtained through open-ended questions. To get more detailed information about the traditional methods used to induce abortion, in-depths interviews and focus group discussions were performed among traditional providers and nurses. Finally, the plant specimen's effectiveness as abortion remedies was assessed through pharmacological analyses. RESULTS: Among women admitted with incomplete abortions, 67% had had an unsafe abortion. Almost half of the women who had experienced an unsafe abortion had resorted to traditional providers and plant species were in these cases often used as abortion remedies. In all 21 plant species were identified as potential abortion remedies and analysed, 16 of the species were found to have a uterine contractive effect; they significantly increased the force of contraction, increased the frequency of contractions or did both. CONCLUSION: Unsafe abortion is common in rural Tanzania where many women use plant species to terminate an unwanted pregnancy. The plants have a remarkable strong uterine contractive effect. To further understand the consequences of unsafe abortion there is a need for further analyses of the plants' potential toxicity and mutagenicity.


Subject(s)
Abortifacient Agents , Abortion, Induced/methods , Medicine, African Traditional/methods , Plant Extracts , Abortifacient Agents/pharmacology , Abortion, Induced/adverse effects , Animals , Attitude of Health Personnel , Female , Focus Groups , Humans , Interviews as Topic , Medicine, African Traditional/adverse effects , Medicine, African Traditional/statistics & numerical data , Muscle Contraction/drug effects , Plant Extracts/pharmacology , Plants, Medicinal , Pregnancy , Rats , Rural Population , Surveys and Questionnaires , Tanzania , Uterus/drug effects
8.
Dan Med J ; 61(1): A4765, 2014 Jan.
Article in English | MEDLINE | ID: mdl-24393590

ABSTRACT

INTRODUCTION: Atrial fibrillation (AF) is a cardiac epidemic. In this study, we aimed to describe the causes of hospital-isation in an AF population over time and to study how different AF treatment strategies affected hospitalization. MATERIAL AND METHODS: This was an observational study in which long-term follow-up data were collected from hospital records, discharge papers and diagnostic codes. The study population (n = 156) was observed over a total period of ten years which was divided into two successive observation periods (OP), OP1 and OP2. Fourteen endpoints of cardiovascular hospitalisations were evaluated. RESULTS: The causes of hospitalisation shifted over time. We observed a lower proportion of admissions due to AF in OP2 (63%) than in OP1 (87%) and a higher proportion of admissions due to congestive heart failure (16% versus 3%) and of days of inpatient care due to ischaemic stroke (25% versus 7%). Persistent AF where sinus rhythm was pursued was associated with a four-fold increase in the risk of hospitalisation (multivariate Poisson analysis, rate ratio 3.97, 95% confidence interval 2.73-5.76, p < 0.0001) compared with accepted permanent AF. CONCLUSION: Over time, the causes of hospitalisation in an AF population shifted from AF relapse to the most frequent complications of AF, ischaemic stroke and congestive heart failure. In this observational study, patients treated with rhythm control were more frequently hospitalised than patients treated with rate control. FUNDING: not relevant. TRIAL REGISTRATION: not relevant.


Subject(s)
Atrial Fibrillation/therapy , Heart Failure/therapy , Hospitalization/trends , Stroke/therapy , Aged , Atrial Fibrillation/complications , Denmark , Female , Follow-Up Studies , Heart Failure/etiology , Hospitalization/statistics & numerical data , Humans , Male , Middle Aged , Multivariate Analysis , Recurrence , Regression Analysis , Stroke/etiology
9.
PLoS One ; 8(1): e52323, 2013.
Article in English | MEDLINE | ID: mdl-23308109

ABSTRACT

We present a full-length α(1)ß(2)γ(2) GABA receptor model optimized for agonists and benzodiazepine (BZD) allosteric modulators. We propose binding hypotheses for the agonists GABA, muscimol and THIP and for the allosteric modulator diazepam (DZP). The receptor model is primarily based on the glutamate-gated chloride channel (GluCl) from C. elegans and includes additional structural information from the prokaryotic ligand-gated ion channel ELIC in a few regions. Available mutational data of the binding sites are well explained by the model and the proposed ligand binding poses. We suggest a GABA binding mode similar to the binding mode of glutamate in the GluCl X-ray structure. Key interactions are predicted with residues α(1)R66, ß(2)T202, α(1)T129, ß(2)E155, ß(2)Y205 and the backbone of ß(2)S156. Muscimol is predicted to bind similarly, however, with minor differences rationalized with quantum mechanical energy calculations. Muscimol key interactions are predicted to be α(1)R66, ß(2)T202, α(1)T129, ß(2)E155, ß(2)Y205 and ß(2)F200. Furthermore, we argue that a water molecule could mediate further interactions between muscimol and the backbone of ß(2)S156 and ß(2)Y157. DZP is predicted to bind with interactions comparable to those of the agonists in the orthosteric site. The carbonyl group of DZP is predicted to interact with two threonines α(1)T206 and γ(2)T142, similar to the acidic moiety of GABA. The chlorine atom of DZP is placed near the important α(1)H101 and the N-methyl group near α(1)Y159, α(1)T206, and α(1)Y209. We present a binding mode of DZP in which the pending phenyl moiety of DZP is buried in the binding pocket and thus shielded from solvent exposure. Our full length GABA(A) receptor is made available as Model S1.


Subject(s)
Benzodiazepines/pharmacology , GABA-A Receptor Agonists/pharmacology , Molecular Docking Simulation , Receptors, GABA-A/chemistry , Receptors, GABA-A/metabolism , Amino Acid Sequence , Animals , Binding Sites , Humans , Molecular Sequence Data , Mutation , Receptors, GABA-A/genetics , Sequence Alignment
10.
Int J Geriatr Psychiatry ; 28(8): 868-76, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23147389

ABSTRACT

BACKGROUND: Psychotropic drugs are extensively prescribed for the treatment of neuropsychiatric symptoms, despite modest efficacy and severe side effects. AIMS: We examined trends in psychotropic drug prescribing in Norwegian nursing homes from 1997 to 2009, in order to gain insight in practice development. METHODS: The study is a secondary data analysis of six cross-sectional nursing home studies conducted between 1997 and 2009. Patients aged >65 years were included. We compared the prevalence of psychotropic drugs (antipsychotics, anxiolytics, hypnotics, and antidepressants). Associations between prescription of psychotropics, and patients' age, gender, type of ward, and year of data collection were examined by univariate analysis and logistic regression. RESULTS: Altogether, 7 661 patients (mean age 85.2 years, 72.6% women) were included. Prevalence of all psychotropic drugs combined increased from 57.6% to 70.5%, anxiolytics from 14.9% to 21.9%, hypnotics from 14.5% to 22.9%, and antidepressants from 31.5% to 50.9%. Prevalence of antipsychotics varied between extremes 21.1% and 25.6%. Less prescribing of older drugs was exceeded by an increase in newer drug types. Concomitant prescribing of two or more psychotropic drugs increased from 21% to 33%. Predictors of psychotropic drugs were female gender (except antipsychotics), as well as age <80 years, and residency in special care units (except hypnotics). CONCLUSIONS: Prescribing of psychotropic drugs in nursing homes has increased considerably, especially regarding antidepressants. Explanations for this trend need to be further explored.


Subject(s)
Drug Prescriptions/statistics & numerical data , Nursing Homes/trends , Psychotropic Drugs/therapeutic use , Aged , Aged, 80 and over , Anti-Anxiety Agents/therapeutic use , Antidepressive Agents/therapeutic use , Antipsychotic Agents/therapeutic use , Cohort Studies , Cross-Sectional Studies , Female , Humans , Hypnotics and Sedatives/therapeutic use , Male , Norway
11.
Stem Cells Dev ; 22(7): 1126-35, 2013 Apr 01.
Article in English | MEDLINE | ID: mdl-23148560

ABSTRACT

Human embryonic stem cells (hESCs) are derived from the inner cell mass (ICM) of the blastocyst and can differentiate into any cell type in the human body. These cells hold a great potential for regenerative medicine, but to obtain enough cells needed for medical treatment, culture is required on a large scale. In the undifferentiated state, hESCs appear to possess an unlimited potential for proliferation, but optimal, defined, and safe culture conditions remain a challenge. The aim of the present study was to identify proteins in the natural environment of undifferentiated hESCs, namely, the blastocoel fluid, which is in contact with all the cells in the blastocyst, including hESCs. Fifty-three surplus human blastocysts were donated after informed consent, and blastocoel fluid was isolated by micromanipulation. Using highly sensitive nano-high-pressure liquid chromatography-tandem mass spectrometry, 286 proteins were identified in the blastocoel fluid and 1,307 proteins in the corresponding cells of the blastocyst. Forty-two were previously uncharacterized proteins-8 of these originated from the blastocoel fluid. Furthermore, several heat shock proteins (Hsp27, Hsp60, Hsc70, and Hsp90) were identified in blastocoel fluid together with zona pellucida proteins (ZP2-4), Vitamin D-binding protein, and Retinol-binding protein 4. Proteins that regulate ciliary assembly and function were also identified, including Bardet-Biedl syndrome protein 7. This study has identified numerous proteins that cells from the ICM of the human blastocyst are exposed to via the blastocoel fluid. These results can be an inspiration for the development of improved culture conditions for hESCs.


Subject(s)
Blastocyst/cytology , Blastocyst/metabolism , Embryonic Stem Cells/cytology , Proteome/analysis , Cell Differentiation , Cell Proliferation , Cells, Cultured , Embryo Culture Techniques , Humans , Proteomics , Vitamin D-Binding Protein/metabolism , Zona Pellucida/metabolism
12.
Proc Natl Acad Sci U S A ; 109(9): 3317-22, 2012 Feb 28.
Article in English | MEDLINE | ID: mdl-22343531

ABSTRACT

Inhibition of the ternary protein complex of the synaptic scaffolding protein postsynaptic density protein-95 (PSD-95), neuronal nitric oxide synthase (nNOS), and the N-methyl-D-aspartate (NMDA) receptor is a potential strategy for treating ischemic brain damage, but high-affinity inhibitors are lacking. Here we report the design and synthesis of a novel dimeric inhibitor, Tat-NPEG4(IETDV)(2) (Tat-N-dimer), which binds the tandem PDZ1-2 domain of PSD-95 with an unprecedented high affinity of 4.6 nM, and displays extensive protease-resistance as evaluated in vitro by stability-measurements in human blood plasma. X-ray crystallography, NMR, and small-angle X-ray scattering (SAXS) deduced a true bivalent interaction between dimeric inhibitor and PDZ1-2, and also provided a dynamic model of the conformational changes of PDZ1-2 induced by the dimeric inhibitor. A single intravenous injection of Tat-N-dimer (3 nmol/g) to mice subjected to focal cerebral ischemia reduces infarct volume with 40% and restores motor functions. Thus, Tat-N-dimer is a highly efficacious neuroprotective agent with therapeutic potential in stroke.


Subject(s)
Infarction, Middle Cerebral Artery/drug therapy , Intracellular Signaling Peptides and Proteins/antagonists & inhibitors , Membrane Proteins/antagonists & inhibitors , Neuroprotective Agents/therapeutic use , Peptides/therapeutic use , Amino Acid Sequence , Animals , Binding Sites , Blood-Brain Barrier , Crystallography, X-Ray , Disks Large Homolog 4 Protein , Drug Design , Drug Evaluation, Preclinical , Guanylate Kinases/antagonists & inhibitors , Humans , Infarction, Middle Cerebral Artery/complications , Infarction, Middle Cerebral Artery/pathology , Learning Disabilities/etiology , Learning Disabilities/prevention & control , Male , Mice , Mice, Inbred C57BL , Models, Molecular , Molecular Sequence Data , Molecular Targeted Therapy , Movement Disorders/etiology , Movement Disorders/prevention & control , Neuroprotective Agents/chemical synthesis , Neuroprotective Agents/pharmacology , Nuclear Magnetic Resonance, Biomolecular , PDZ Domains/drug effects , Peptides/chemical synthesis , Peptides/pharmacology , Postural Balance , Protein Conformation , Sensation Disorders/etiology , Sensation Disorders/prevention & control
13.
J Mol Biol ; 412(3): 466-80, 2011 Sep 23.
Article in English | MEDLINE | ID: mdl-21827767

ABSTRACT

Lactobacillus acidophilus NCFM is a probiotic bacterium known for its beneficial effects on human health. The importance of α-galactosidases (α-Gals) for growth of probiotic organisms on oligosaccharides of the raffinose family present in many foods is increasingly recognized. Here, the crystal structure of α-Gal from L. acidophilus NCFM (LaMel36A) of glycoside hydrolase (GH) family 36 (GH36) is determined by single-wavelength anomalous dispersion. In addition, a 1.58-Å-resolution crystallographic complex with α-d-galactose at substrate binding subsite -1 was determined. LaMel36A has a large N-terminal twisted ß-sandwich domain, connected by a long α-helix to the catalytic (ß/α)(8)-barrel domain, and a C-terminal ß-sheet domain. Four identical monomers form a tightly packed tetramer where three monomers contribute to the structural integrity of the active site in each monomer. Structural comparison of LaMel36A with the monomeric Thermotoga maritima α-Gal (TmGal36A) reveals that O2 of α-d-galactose in LaMel36A interacts with a backbone nitrogen in a glycine-rich loop of the catalytic domain, whereas the corresponding atom in TmGal36A is from a tryptophan side chain belonging to the N-terminal domain. Thus, two distinctly different structural motifs participate in substrate recognition. The tetrameric LaMel36A furthermore has a much deeper active site than the monomeric TmGal36A, which possibly modulates substrate specificity. Sequence analysis of GH36, inspired by the observed structural differences, results in four distinct subgroups having clearly different active-site sequence motifs. This novel subdivision incorporates functional and architectural features and may aid further biochemical and structural analyses within GH36.


Subject(s)
Galactose/chemistry , Galactose/metabolism , Lactobacillus acidophilus/enzymology , Protein Multimerization , alpha-Galactosidase/chemistry , alpha-Galactosidase/metabolism , Catalytic Domain , Crystallography, X-Ray , Lactobacillus acidophilus/chemistry , Models, Molecular , Phylogeny , Protein Binding , Protein Structure, Quaternary , Protein Structure, Tertiary , Sequence Homology, Amino Acid , Thermotoga maritima/chemistry , Thermotoga maritima/enzymology
14.
J Ethnopharmacol ; 137(1): 921-5, 2011 Sep 01.
Article in English | MEDLINE | ID: mdl-21645605

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Women in Tanzania use plants to induce abortion. It is not known whether the plants have an effect. AIMS OF STUDY: Collect data on plant use in relation to induced abortion and test the effect of plant extracts on uterine contraction. MATERIALS AND METHODS: During interviews with traditional birth attendants and nurses, plants were identified. Cumulative doses of plant extracts were added to rat uterine tissue in an organ bath, and the force and frequency of contractions recorded. Acetylcholine was used as positive control. RESULTS: 21 plant species were tested for effect on uterine contraction. 11 species increased the force of contraction, and 12 species the frequency of contractions. The strongest contractions comparable to the maximum response obtained with acetylcholine were obtained with extracts of Bidens pilosa, Commelina africana, Desmodium barbatum, Manihot esculenta, Ocimum suave, Oldenlandia corymbosa and Sphaerogyne latifolia. 7 species increased both the force and frequency of contractions. CONCLUSION: Several of the plant species induced strong and frequent contractions of the uterus, and can be used to induce an abortion.


Subject(s)
Abortifacient Agents/therapeutic use , Abortion, Induced , Plant Extracts/therapeutic use , Uterine Contraction/drug effects , Acetylcholine/pharmacology , Animals , Dose-Response Relationship, Drug , Female , Health Knowledge, Attitudes, Practice , Humans , In Vitro Techniques , Interviews as Topic , Medicine, Traditional , Midwifery , Nurses , Plants, Medicinal , Pregnancy , Rats , Rats, Sprague-Dawley , Tanzania
15.
Reprod Biomed Online ; 20(4): 477-84, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20129825

ABSTRACT

The effect on ploidy rate in donated human oocytes after in-vitro culture with recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF; 2 ng/ml) from fertilization until day 3 was examined in a multicentre, prospective placebo-controlled and double-blinded study including 73 women donating 86 oocytes. The primary endpoint was to investigate the chromosomal constitution of human embryos (fluorescence in-situ hybridization analysis for chromosomes 13, 16, 18, 21, 22, X and Y) cultured with or without GM-CSF. The secondary endpoints were number of top-quality embryos (TQE) and number of normally developed embryos evaluated morphologically on day 3. The cytogenetic analyses demonstrated non-inferiority and therefore the chromosomal constitution of human embryos cultured in vitro in the presence of 2 ng/ml GM-CSF was no worse than the control group cultured without GM-CSF. In-vitro culture of human embryos in the presence of 2 ng/ml GM-CSF resulted in 34.8% (8/23) uniformly normal embryos. Culture without 2 ng/ml GM-CSF resulted in 33.3% (9/27) uniformly normal embryos. A trend towards a higher number of TQE in the test group was observed; however, due to lack of TQE in the control group, this was considered a random finding.


Subject(s)
Chromosomes, Human/genetics , Embryo, Mammalian/drug effects , Granulocyte-Macrophage Colony-Stimulating Factor/pharmacology , Oocytes/cytology , Adult , Cells, Cultured , Chromosomes, Human/drug effects , Female , Fertilization in Vitro , Humans , In Situ Hybridization, Fluorescence , Ploidies , Recombinant Proteins , Sperm Injections, Intracytoplasmic
16.
Oecologia ; 155(4): 771-83, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18246373

ABSTRACT

Soil microbes constitute an important control on nitrogen (N) turnover and retention in arctic ecosystems where N availability is the main constraint on primary production. Ectomycorrhizal (ECM) symbioses may facilitate plant competition for the specific N pools available in various arctic ecosystems. We report here our study on the N uptake patterns of coexisting plants and microbes at two tundra sites with contrasting dominance of the circumpolar ECM shrub Betula nana. We added equimolar mixtures of glycine-N, NH4+ -N and NO3(-) -N, with one N form labelled with 15N at a time, and in the case of glycine, also labelled with 13C, either directly to the soil or to ECM fungal ingrowth bags. After 2 days, the vegetation contained 5.6, 7.7 and 9.1% (heath tundra) and 7.1, 14.3 and 12.5% (shrub tundra) of the glycine-, NH4+ - and NO3 (-) -(15)N, respectively, recovered in the plant-soil system, and the major part of 15N in the soil was immobilized by microbes (chloroform fumigation-extraction). In the subsequent 24 days, microbial N turnover transferred about half of the immobilized 15N to the non-extractable soil organic N pool, demonstrating that soil microbes played a major role in N turnover and retention in both tundra types. The ECM mycelial communities at the two tundras differed in N-form preferences, with a higher contribution of glycine to total N uptake at the heath tundra; however, the ECM mycelial communities at both sites strongly discriminated against NO3 (-) . Betula nana did not directly reflect ECM mycelial N uptake, and we conclude that N uptake by ECM plants is modulated by the N uptake patterns of both fungal and plant components of the symbiosis and by competitive interactions in the soil. Our field study furthermore showed that intact free amino acids are potentially important N sources for arctic ECM fungi and plants as well as for soil microorganisms.


Subject(s)
Betula/metabolism , Ecosystem , Mycorrhizae/metabolism , Nitrogen/metabolism , Soil Microbiology , Arctic Regions , Bacteria/metabolism , Betula/chemistry , Carbon/analysis , Carbon/metabolism , Glycine/metabolism , Nitrogen/analysis , Nitrogen/chemistry , Nitrogen Isotopes/analysis , Soil/analysis
17.
AIDS Res Hum Retroviruses ; 18(12): 861-6, 2002 Aug 10.
Article in English | MEDLINE | ID: mdl-12201909

ABSTRACT

The transmissibility of the human endogenous retrovirus HERV-H/RGH-2 was investigated by marker rescue: intraspecies transmission of HERV-H/RGH-2 retrovirus particles was attempted by cocultivation of virion-producing, long-term cell cultures spontaneously formed from peripheral blood mononuclear cells from several multiple sclerosis patient cultures with a retroviral vector construct-harboring cell line. Transmissibility was assessed by assays for productive infection (reverse transcriptase activity), and assays for rescue of the retroviral vector construct in indicator cells. Our studies show that the human endogenous retrovirus HERV-H/RGH-2 is transmissible, albeit at a very low level. The human endogenous retrovirus HERV-H/RGH-2 is associated with multiple sclerosis (MS). Previously, we demonstrated sequence variants of the human endogenous retrovirus HERV-H family in virion form, by applying RT-PCR to virion RNA from the supernatants of long-term MS cell cultures, and to the particulate fraction of a series of MS patient plasma samples.


Subject(s)
Endogenous Retroviruses/isolation & purification , Cell Line , Coculture Techniques , Endogenous Retroviruses/genetics , Humans , Multiple Sclerosis/pathology , Multiple Sclerosis/virology , Retroviridae Infections/transmission , Retroviridae Infections/virology , Reverse Transcriptase Polymerase Chain Reaction , beta-Galactosidase/genetics
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