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1.
PLoS Pathog ; 19(12): e1011793, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38064525

RESUMO

Like all herpesviruses, cytomegaloviruses (CMVs) code for many immunomodulatory proteins including chemokines. The human cytomegalovirus (HCMV) CC chemokine pUL128 has a dual role in the infection cycle. On one hand, it forms the pentameric receptor-binding complex gHgLpUL(128,130,131A), which is crucial for the broad cell tropism of HCMV. On the other hand, it is an active chemokine that attracts leukocytes and shapes their activation. All animal CMVs studied so far have functionally homologous CC chemokines. In murine cytomegalovirus (MCMV), the CC chemokine is encoded by the m131/m129 reading frames. The MCMV CC chemokine is called MCK2 and forms a trimeric gHgLMCK2 entry complex. Here, we have generated MCK2 mutant viruses either unable to form gHgLMCK2 complexes, lacking the chemokine function or lacking both functions. By using these viruses, we could demonstrate that gHgLMCK2-dependent entry and MCK2 chemokine activity are independent functions of MCK2 in vitro and in vivo. The gHgLMCK2 complex promotes the tropism for leukocytes like macrophages and dendritic cells and secures high titers in salivary glands in MCMV-infected mice independent of the chemokine activity of MCK2. In contrast, reduced early antiviral T cell responses in MCMV-infected mice are dependent on MCK2 being an active chemokine and do not require the formation of gHgLMCK2 complexes. High levels of CCL2 and IFN-γ in spleens of infected mice and MCMV virulence depend on both, the formation of gHgLMCK2 complexes and the MCK2 chemokine activity. Thus, independent and concerted functions of MCK2 serving as chemokine and part of a gHgL entry complex shape antiviral immunity and virus dissemination.


Assuntos
Infecções por Citomegalovirus , Muromegalovirus , Animais , Camundongos , Humanos , Citomegalovirus/metabolismo , Quimiocinas CC , Quimiocinas/metabolismo , Tropismo , Proteínas Virais/genética
2.
Dermatologie (Heidelb) ; 74(2): 122-125, 2023 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-36107202

RESUMO

This article presents the case of a patient with massive pruritus sine materia. Naloxone was proven as quick and effective therapy which led to a complete reduction of itching.


Assuntos
Naloxona , Prurido , Humanos , Naloxona/uso terapêutico , Prurido/tratamento farmacológico
3.
JMIR Form Res ; 6(3): e33635, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35230250

RESUMO

BACKGROUND: Fitness trackers and smart watches are frequently used to collect data in longitudinal medical studies. They allow continuous recording in real-life settings, potentially revealing previously uncaptured variabilities of biophysiological parameters and diseases. Adequate device accuracy is a prerequisite for meaningful research. OBJECTIVE: This study aims to assess the heart rate recording accuracy in two previously unvalidated devices: Fitbit Charge 4 and Samsung Galaxy Watch Active2. METHODS: Participants performed a study protocol comprising 5 resting and sedentary, 2 low-intensity, and 3 high-intensity exercise phases, lasting an average of 19 minutes 27 seconds. Participants wore two wearables simultaneously during all activities: Fitbit Charge 4 and Samsung Galaxy Watch Active2. Reference heart rate data were recorded using a medically certified Holter electrocardiogram. The data of the reference and evaluated devices were synchronized and compared at 1-second intervals. The mean, mean absolute error, mean absolute percentage error, Lin concordance correlation coefficient, Pearson correlation coefficient, and Bland-Altman plots were analyzed. RESULTS: A total of 23 healthy adults (mean age 24.2, SD 4.6 years) participated in our study. Overall, and across all activities, the Fitbit Charge 4 slightly underestimated the heart rate, whereas the Samsung Galaxy Watch Active2 overestimated it (-1.66 beats per minute [bpm]/3.84 bpm). The Fitbit Charge 4 achieved a lower mean absolute error during resting and sedentary activities (seated rest: 7.8 vs 9.4; typing: 8.1 vs 11.6; laying down [left]: 7.2 vs 9.4; laying down [back]: 6.0 vs 8.6; and walking slowly: 6.8 vs 7.7 bpm), whereas the Samsung Galaxy Watch Active2 performed better during and after low- and high-intensity activities (standing up: 12.3 vs 9.0; walking fast: 6.1 vs 5.8; stairs: 8.8 vs 6.9; squats: 15.7 vs 6.1; resting: 9.6 vs 5.6 bpm). CONCLUSIONS: Device accuracy varied with activity. Overall, both devices achieved a mean absolute percentage error of just <10%. Thus, they were considered to produce valid results based on the limits established by previous work in the field. Neither device reached sufficient accuracy during seated rest or keyboard typing. Thus, both devices may be eligible for use in respective studies; however, researchers should consider their individual study requirements.

4.
Praxis (Bern 1994) ; 110(11): 619-620, 2021 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-34465197

RESUMO

CME/Answers: Mushroom Poisoning in the Family Practice Abstract. In the general medical practice, it is not trivial to distinguish between banal intolerances after consumption of edible mushrooms and the initial symptoms of poisoning with potentially fatal outcome. Nevertheless, there are some criteria that can be used as clinical guidance: A latency of six hours or more between the consumption of gilled mushrooms that have not been checked by experts and the onset of mostly severe vomiting and diarrhea is indicative of poisoning with amatoxins, the toxins i.e. in death caps (Amanita phalloides). Although the therapeutic options are controversial, prompt antidotal treatment with silibinin has proven to be effective.


Assuntos
Intoxicação Alimentar por Cogumelos , Amanita , Diarreia , Medicina de Família e Comunidade , Humanos , Intoxicação Alimentar por Cogumelos/diagnóstico , Intoxicação Alimentar por Cogumelos/terapia
5.
Praxis (Bern 1994) ; 110(10): 543-553, 2021 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-34344191

RESUMO

CME: Mushroom Poisoning in the Family Practice Abstract. In the general medical practice, it is not trivial to distinguish between banal intolerances after consumption of edible mushrooms and the initial symptoms of poisoning with potentially fatal outcome. Nevertheless, there are some criteria that can be used as clinical guidance: A latency of six hours or more between the consumption of gilled mushrooms that have not been checked by experts and the onset of mostly severe vomiting and diarrhea is indicative of poisoning with amatoxins, the toxins i.e. in death caps (Amanita phalloides). Although the therapeutic options are controversial, prompt antidotal treatment with silibinin has proven to be effective.


Assuntos
Intoxicação Alimentar por Cogumelos , Amanita , Medicina de Família e Comunidade , Humanos , Intoxicação Alimentar por Cogumelos/diagnóstico , Intoxicação Alimentar por Cogumelos/terapia
6.
mBio ; 10(3)2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31113903

RESUMO

The biomineralization pathway of magnetite in magnetotactic bacteria is still poorly understood and a matter of intense debates. In particular, the existence, nature, and location of possible mineral precursors of magnetite are not clear. One possible precursor has been suggested to be ferritin-bound ferrihydrite. To clarify its role for magnetite biomineralization, we analyzed and characterized ferritin-like proteins from the magnetotactic alphaproteobacterium Magnetospirillum gryphiswaldense MSR-1, employing genetic, biochemical, and spectroscopic techniques. Transmission Mössbauer spectroscopy of the wild type (WT) and a bacterioferritin (bfr) deletion strain uncovered that the presence of ferrihydrite in cells is coupled to the presence of Bfr. However, bfr and dps deletion mutants, encoding another ferritin-like protein, or even mutants with their codeletion had no impact on magnetite formation in MSR-1. Thus, ferritin-like proteins are not involved in magnetite biomineralization and Bfr-bound ferrihydrite is not a precursor of magnetite biosynthesis. Using transmission electron microscopy and bacterial two-hybrid and electrophoretic methods, we also show that MSR-1 Bfr is an atypical representative of the Bfr subfamily, as it forms tetraeicosameric complexes from two distinct subunits. Furthermore, our analyses revealed that these subunits are functionally divergent, with Bfr1 harboring a ferroxidase activity while only Bfr2 contributes to heme binding. Because of this functional differentiation and the poor formation of homooligomeric Bfr1 complexes, only heterooligomeric Bfr protects cells from oxidative stress in vivo. In summary, our results not only provide novel insights into the biomineralization of magnetite but also reveal the unique properties of so-far-uncharacterized heterooligomeric bacterioferritins.IMPORTANCE Magnetotactic bacteria like Magnetospirillum gryphiswaldense are able to orient along magnetic field lines due to the intracellular formation of magnetite nanoparticles. Biomineralization of magnetite has been suggested to require a yet-unknown ferritin-like ferrihydrite component. Here, we report the identification of a bacterioferritin as the source of ferrihydrite in M. gryphiswaldense and show that, contrary to previous reports, bacterioferritin is not involved in magnetite biomineralization but required for oxidative stress resistance. Additionally, we show that bacterioferritin of M. gryphiswaldense is an unusual member of the bacterioferritin subfamily as it is composed of two functionally distinct subunits. Thus, our findings extend our understanding of the bacterioferritin subfamily and also solve a longstanding question about the magnetite biomineralization pathway.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Biomineralização , Grupo dos Citocromos b/química , Grupo dos Citocromos b/metabolismo , Ferritinas/química , Ferritinas/metabolismo , Óxido Ferroso-Férrico/metabolismo , Magnetospirillum/química , Magnetospirillum/metabolismo , Proteínas de Bactérias/genética , Grupo dos Citocromos b/deficiência , Grupo dos Citocromos b/genética , Compostos Férricos/metabolismo , Ferritinas/deficiência , Ferritinas/genética , Deleção de Genes , Magnetospirillum/genética , Redes e Vias Metabólicas/genética
7.
Cancers (Basel) ; 11(1)2019 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-30641895

RESUMO

Regulation of particular genes during the formation of neural crest (NC) cells is also described during progression of malignant melanoma. In this context, it is of paramount importance to develop neural crest models allowing the identification of candidate genes, which could be used as biomarkers for melanoma prognosis. Here, we used a human induced Pluripotent Stem Cells (iPSC)-based approach to present novel NC-associated genes, expression of which was upregulated in melanoma. A list of 8 candidate genes, based on highest upregulation, was tested for prognostic value in a tissue microarray analysis containing samples from advanced melanoma (good versus bad prognosis) as well as from high-risk primary melanomas (early metastasizing versus non or late-metastasizing). CD271, GLDC, and ERRFI1 showed significantly higher expression in metastatic patients who died early than the ones who survived at least 30 months. In addition, GLDC and TWIST showed a significantly higher immunohistochemistry (IHC) score in primary melanomas from patients who developed metastases within 12 months versus those who did not develop metastases in 30 months. In conclusion, our iPSC-based study reveals a significant association of NC marker GLDC protein expression with melanoma prognosis.

8.
PLoS One ; 11(9): e0162314, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27648562

RESUMO

Changes in the ecology of macrofungi are poorly understood, not only because much of their life cycle is hidden belowground, but also because experiments often miss real-world complexity and most fruitbody inventories are limited in space and time. The National Poisons Information Centre 'Tox Info Suisse' provides countrywide 24hours/7days medical advice in case of poisonings since 1966. Here, we introduce a total of 12,126 mushroom-related phone calls that were received by Tox Info Suisse between 1966 and 2014. This indirect source of mycological information is dominated by the families of Boletaceae (11%), Agaricaceae (10%) and Amanitaceae (8%), which account for ~30% of all cases. Mushroom fruiting patterns revealed by the Poisons Centre inventory statistically resemble changes in fungal phenology, productivity and diversity as reflected by the Swiss National Data Centre 'SwissFungi'. Although the newly developed Tox Info Suisse dataset provides an innovative basis for timely environmental research, caution is advised when interpreting some of the observed long-term changes and autumnal extremes. Uncertainty of the new record relates to possible data incompleteness, imprecise species description and/or identification, as well as the inclusion of cultivated and non-indigenous mushrooms. Nevertheless, we hope that the Tox Info Suisse inventory will stimulate and enable a variety of ecological-oriented follow-up studies.


Assuntos
Agaricales , Carpóforos , Micotoxicose/etiologia , Agaricales/classificação , Clima , Carpóforos/classificação , Humanos , Centros de Informação , Estações do Ano , Especificidade da Espécie , Suíça/epidemiologia
9.
Chemistry ; 18(35): 10903-15, 2012 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-22807262

RESUMO

Polycyclic azoniahetarenes were employed to determine the effect of the structure of unsubstituted polyaromatic ligands on their quadruplex-DNA binding properties. The interactions of three isomeric diazoniadibenzo[b,k]chrysenes (4 a-c), diazoniapentaphene (5), diazoniaanthra[1,2-a]anthracene (6), and tetraazoniapentapheno[6,7-h]pentaphene (3) with quadruplex DNA were examined by DNA melting studies (FRET melting) and fluorimetric titrations. In general, penta- and hexacyclic azoniahetarenes bind to quadruplex DNA (K(b) ≈10(6) M(-1)) even in the absence of additional functional side chains. The binding modes of 4 a-c and 3 were studied in more detail by ligand displacement experiments, isothermal titration calorimetry, and CD and NMR spectroscopy. All experimental data indicate that terminal π stacking of the diazoniachrysenes to the quadruplex is the major binding mode; however, because of different electron distributions of the π systems of each isomer, these ligands align differently in the binding site to achieve ideal binding interactions. It is proposed that tetraazonia ligand 3 binds to the quadruplex by terminal stacking with a small portion of its π system, whereas a significant part of the bulky ligand most likely points outside the quadruplex structure, and is thus partially placed in the grooves. Notably, 3 and the known tetracationic porphyrin TMPyP4 exhibit almost the same binding properties towards quadruplex DNA, with 3 being more selective for quadruplex than for duplex DNA. Overall, studies on azonia-type hetarenes enable understanding of some parameters that govern the quadruplex-binding properties of parent ligand systems. Since unsubstituted ligands were employed in this study, complementary and cooperative effects of additional substituents, which may interfere with the ligand properties, were eliminated.


Assuntos
Antracenos/síntese química , Antineoplásicos/síntese química , Compostos Azo/síntese química , Substâncias Intercalantes/síntese química , Quinolinas/síntese química , Sítios de Ligação , Calorimetria , Dicroísmo Circular , Transferência Ressonante de Energia de Fluorescência , Quadruplex G , Humanos , Ligantes , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Desnaturação de Ácido Nucleico/efeitos dos fármacos , Termodinâmica , Água
10.
Ther Umsch ; 66(5): 357-64, 2009 May.
Artigo em Alemão | MEDLINE | ID: mdl-19401986

RESUMO

Most mushroom intoxications become evident within 12 hours with vomiting and diarrhea. They can be divided into incidents with a short latency (less than four hours) and incidents with a long latency (longer than four hours). As a rule of thumb amatoxin poisonings must be considered in case of symptoms appearing with a long latency (8-12-18 h), especially after consumption of non-controlled wild mushrooms. Shorter latencies do not exclude amatoxin poisoning. Large meals of mushrooms, which are rich in chitin, mixed meals and individual factors, may shorten latency and disguise amatoxin poisoning. Any vomiting and diarrhea after mushroom consumption is suspicious. Unless the mushrooms are not to be identified within 30 minutes by an expert, specific treatment for amatoxin poisoning must be started. Identification shall be achieved by macroscopic or microscopic means; and urine analysis for amatoxins are crucial. By commencing treatment before analysis, mortality rates may be as low as 5%. Current standards in amatoxin poisoning treatment can be obtained at the Swiss Toxicological Information Centre (Phone 145), where contacts to mycologists are available as well. Emergency mycologists are listed on the website www.vapko.ch. Of the 18 different syndromes we present the most common and most important in Switzerland. In an overview all of them are listed. Early gastrointestinal syndrome with its short latency of less than 4 h and indigestion with a very variable latency are the most common. Psychotropic symptoms after consumptions of fly agaric and panther cap are rare, in case of psilocybin-containing mushrooms, symptoms are frequent, but hardly ever lead to medical treatment. In case of renal failure and rhabdomyolysis of unknown origin, completing a patient's history by questioning nutritional habits might reveal causal relationship with ingestion of orellanin-containing mushrooms or tricholoma equestre respectively. Mushrooms in the backyard are attractive for children. We discuss possible approaches.


Assuntos
Emergências , Intoxicação Alimentar por Cogumelos/terapia , Adulto , Criança , Humanos , Intoxicação Alimentar por Cogumelos/etiologia , Micotoxinas/análise , Micotoxinas/envenenamento
11.
Chem Commun (Camb) ; (10): 1249-51, 2009 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-19240889

RESUMO

It is demonstrated that even unsubstituted cationic ligands, namely the known diazoniadibenzochrysenes (, ) and the so far unreported tetraazoniapentaphenopentaphene (), stabilize quadruplex DNA upon association; the ligand exhibits essentially the same affinity towards the quadruplex as does 5,10,15,20-tetrakis(1-methyl-4-pyridyl)-21H,23H-porphine, however, with a significantly higher selectivity for quadruplex relative to duplex DNA.


Assuntos
Compostos de Diazônio/química , Quadruplex G , Compostos Policíclicos/química , Cátions/química , Dicroísmo Circular , Ligantes , Estrutura Molecular
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