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1.
Nature ; 565(7737): 86-90, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30532001

RESUMO

Animals and humans display two types of response to noxious stimuli. The first includes reflexive defensive responses that prevent or limit injury; a well-known example of these responses is the quick withdrawal of one's hand upon touching a hot object. When the first-line response fails to prevent tissue damage (for example, a finger is burnt), the resulting pain invokes a second-line coping response-such as licking the injured area to soothe suffering. However, the underlying neural circuits that drive these two strings of behaviour remain poorly understood. Here we show in mice that spinal neurons marked by coexpression of TAC1Cre and LBX1Flpo drive coping responses associated with pain. Ablation of these spinal neurons led to the loss of both persistent licking and conditioned aversion evoked by stimuli (including skin pinching and burn injury) that-in humans-produce sustained pain, without affecting any of the reflexive defensive reactions that we tested. This selective indifference to sustained pain resembles the phenotype seen in humans with lesions of medial thalamic nuclei1-3. Consistently, spinal TAC1-lineage neurons are connected to medial thalamic nuclei by direct projections and via indirect routes through the superior lateral parabrachial nuclei. Furthermore, the anatomical and functional segregation observed at the spinal level also applies to primary sensory neurons. For example, in response to noxious mechanical stimuli, MRGPRD- and TRPV1-positive nociceptors are required to elicit reflexive and coping responses, respectively. Our study therefore reveals a fundamental subdivision within the cutaneous somatosensory system, and challenges the validity of using reflexive defensive responses to measure sustained pain.


Assuntos
Adaptação Psicológica/fisiologia , Dor Crônica/fisiopatologia , Dor Crônica/psicologia , Vias Neurais/fisiologia , Animais , Aprendizagem da Esquiva , Condicionamento Clássico , Feminino , Humanos , Masculino , Núcleo Mediodorsal do Tálamo/citologia , Núcleo Mediodorsal do Tálamo/fisiologia , Camundongos , Neurônios Aferentes/fisiologia , Núcleos Parabraquiais/citologia , Núcleos Parabraquiais/fisiologia , Precursores de Proteínas/genética , Precursores de Proteínas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Canais de Cátion TRPV/metabolismo , Taquicininas/genética , Taquicininas/metabolismo
2.
Anesth Analg ; 134(5): 974-986, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-34889805

RESUMO

BACKGROUND: Chronic posttraumatic/postsurgical pain (CPSP) is common after traumatic or surgical damage. Exposure to both trauma and surgery, with the potential for repeated bone and nerve damage, may increase the risk of CPSP after fracture-related surgery. But the (long-term) incidences of CPSP and neuropathic CPSP and the ensuing burdens are unknown. Therefore, the patients were prospectively assessed within 1 year, and the patient-specific characteristics were explored. METHODS: Between 2017 and 2018, 127 patients (age: 52.9 ± 17.1 years, male: 55.1%) with traumatic fractures needing osteosynthesis (extremities: 91.3%) were assessed posttrauma (before surgery), postsurgery at days 1 to 5, 6 weeks, 3 and 12 months. The primary outcomes are as follows: incidence at 3 and 12 months of CPSP (defined as pain intensity on a numerical rating scale [NRS: 0-10] ≥3), secondary exploration: neuropathic CPSP (NRS ≥3 and Douleur Neuropathique 4 interview [DN4i] score ≥3 [Douleur Neuropathique interview: 0-7]); burden: quality of life (QoL, the EuroQOL five dimensions questionnaire [EQ-5D-3L] descriptive system); and inter alia, the number of analgesics (trial registration: DRKS00011601). RESULTS: The incidence of CPSP was 57.1% (52/91, n/N) at 3 and 42.7% (35/82) at 12 months postsurgery, including neuropathic CPSP 7.7% (4/52) and 17.1% (6/35), respectively. Descriptively, posttraumatic higher pain intensity at rest (difference of 0.9 ± 1.8 NRS) and the need for more frequent analgesics (by 34.3%) were associated with CPSP a year after surgery compared to those without. As soon as week 6, these patients had developed descriptively a 15% more impaired QoL, with 25% more impairment after 1 year. The patients with CPSP presented with at least 1 neuropathic symptom 12 months later in 68.6% (24/35) of cases, mainly with an early posttraumatic occurrence (without fulfilling the definition of neuropathic CPSP). CONCLUSIONS: After early fracture-related surgery, high incidences of CPSP (43%) were prospectively observed 1 year postsurgery, up to approximately 1 in 5 patients who had neuropathic CPSP. At the same time, CPSP was accompanied with an impacted QoL and analgesic dependence, both indicating clinical relevance. Moreover, the high incidence and the early posttraumatic occurrence of more intense pain suggest that the initial fracture-related trauma, rather than the surgical trauma, may predominantly trigger CPSP at Y1 (1 year). Therefore, these exploratory results set the direction of required future research. A future clinical hypothesis might be: treat first what hurts first.


Assuntos
Dor Crônica , Fraturas Ósseas , Adulto , Idoso , Analgésicos , Dor Crônica/diagnóstico , Dor Crônica/epidemiologia , Dor Crônica/etiologia , Seguimentos , Fraturas Ósseas/complicações , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor/efeitos adversos , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/epidemiologia , Dor Pós-Operatória/etiologia , Qualidade de Vida
3.
Int J Mol Sci ; 23(9)2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35563669

RESUMO

BACKGROUND: Capsaicin, the hot pepper agent, produces burning followed by desensitization. To treat localized itch or pain with minimal burning, low capsaicin concentrations can be repeatedly applied. We hypothesized that alternatively controlled release of capsaicin from poly(lactic-co-glycolic acid) (PLGA) nanoparticles desensitizes superficially terminating nociceptors, reducing burning. METHODS: Capsaicin-loaded PLGA nanoparticles were prepared (single-emulsion solvent evaporation) and characterized (size, morphology, capsaicin loading, encapsulation efficiency, in vitro release profile). Capsaicin-PLGA nanoparticles were applied to murine skin and evaluated in healthy human participants (n = 21) for 4 days under blinded conditions, and itch and nociceptive sensations evoked by mechanical, heat stimuli and pruritogens cowhage, ß-alanine, BAM8-22 and histamine were evaluated. RESULTS: Nanoparticles (loading: 58 µg capsaicin/mg) released in vitro 23% capsaicin within the first hour and had complete release at 72 h. In mice, 24 h post-application Capsaicin-PLGA nanoparticles penetrated the dermis and led to decreased nociceptive behavioral responses to heat and mechanical stimulation (desensitization). Application in humans produced a weak to moderate burning, dissipating after 3 h. A loss of heat pain up to 2 weeks was observed. After capsaicin nanoparticles, itch and nociceptive sensations were reduced in response to pruritogens cowhage, ß-alanine or BAM8-22, but were normal to histamine. CONCLUSIONS: Capsaicin nanoparticles could be useful in reducing pain and itch associated with pruritic diseases that are histamine-independent.


Assuntos
Capsaicina , Nanopartículas , Animais , Capsaicina/farmacologia , Glicóis , Histamina , Temperatura Alta , Humanos , Camundongos , Dor/tratamento farmacológico , Prurido/induzido quimicamente , Prurido/tratamento farmacológico , beta-Alanina
4.
J Intensive Care Med ; 36(11): 1313-1322, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32799703

RESUMO

PURPOSE: Intensive care unit-acquired weakness (ICUAW) can manifest as muscle weakness or neuropathy-like symptoms, with diagnosis remaining a challenge. Uncertainties surround the long-term cause and sequelae. Therefore, the purpose was to assess incidence, time course and long-term influence on quality of life (QoL) of symptoms in ICU survivors. METHODS: After ethical approval and registration (www.drks.de: DRKS00011593), in a single-center cohort study all patients admitted to the ICU in 2007-2017 in a German university hospital were screened. Out of 1,860 patients (≥7d ICU care including ventilation support for ≥72 h, at least 6mo-10y after ICU) 636 were deceased, 912 survivors were contacted. RESULTS: 149 former patients (age: 63.5 ± 13.1y; males: 73%; duration in ICU: 20.8 ± 15.7d; duration of ventilation: 16.5 ± 13.7 h; time post-ICU: 4.4 ± 2.7y, 5-10y: 43%) consented to be interviewed concerning occurrence, duration, recovery and consequences of ICUAW-associated muscle weakness or neuropathy-like symptoms after ICU. In 75% at least 1 persistent or previous symmetrical symptom was reported (myopathy-like muscle weakness: 43%; neuropathy-like symptoms: 13%; both: 44%) and rated as incidence of ICUAW. However, only 18% of participants had received an ICUAW diagnosis by their physicians, although 62% had persistent symptoms up to 10y after ICU (5-10y: 46%). Only 37% of participants reported a complete recovery of symptoms, significantly associated with an initially low number of symptoms after ICU (p < 0.0001), myopathy-like symptoms (p = 0.024), and younger age at the time of ICU admission (55.7 ± 13.1 vs. 62.6 ± 10.6y, p < 0.001). ICUAW still impaired the QoL at the time of the interview in 74% of affected survivors, with 30% reporting severe impairment. CONCLUSION: ICUAW symptoms were disturbingly common in the majority of long-term survivors, indicating that symptoms persist up to 10y and frequently impair QoL. However, only a small number of patients had been diagnosed with ICUAW. Trial registry: Deutsches Register Klinischer Studien (DRKS), https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00011593, registration number: DRKS00011593.


Assuntos
Unidades de Terapia Intensiva , Qualidade de Vida , Idoso , Estudos de Coortes , Cuidados Críticos , Estado Terminal , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Sobreviventes
5.
Curr Med Res Opin ; 37(12): 2035-2042, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34515599

RESUMO

OBJECTIVES: Inhalative anesthesia is of common use, but is generally known to potentiate postoperative nausea and vomiting (PONV). With an internal change of anesthesia regimen from total intravenous anesthesia (TIVA) to isoflurane (in terms of myocardial protection) in cardiac anesthesia a higher incidence of PONV was to be expected. Therefore, we evaluated the incidence of PONV after the simultaneous implementation of PONV prophylaxis. METHODS: The incidence of PONV, prospectively assessed in 197 cardiac surgery patients (68 y ± 10.4, 66.5% male) having isoflurane plus dual PONV prophylaxis with dexamethasone and droperidol, was compared with previous data of 190 controls (67 y ± 9.6, 71% male) having TIVA without and with single or dual PONV prophylaxis (n = 64 dexamethasone and droperidol, n = 25 dexamethasone, n = 101 only TIVA), and the Apfel-scoring (0-4 depending on PONV-risk). DRKS00014275. Statistics: Chi2-test, p < .05 (Bonferroni). RESULTS: The incidence of PONV under isoflurane with antiemetic prophylaxis was 20.8% (95% confidence interval (CI) 15.4; 27.4) compared to 30.5% (95%CI 24; 37.6) under TIVA (p = .029; dexamethasone and droperidol 23.4% (95%CI 13.8; 35.7); dexamethasone 32% (95%CI 14.9; 53.5); only TIVA 34.7% (95%CI 25.5; 44.8)), but was not lower in high-risk patients than predicted according to Apfel-scoring 4 (71.4 vs. 78%). CONCLUSION: In cardiac anesthesia, the use of isoflurane is not at the expense of PONV when using a risk-independent two-drug-prophylaxis. It is even beneficial resulting surprisingly in a lower incidence of PONV than under TIVA unless with and without prophylaxis. Patients with the highest risk for PONV and receiving isoflurane should receive a third antiemetic prophylactic drug.


Assuntos
Anestesia em Procedimentos Cardíacos , Antieméticos , Isoflurano , Propofol , Anestesia Geral , Antieméticos/uso terapêutico , Feminino , Humanos , Isoflurano/efeitos adversos , Masculino , Náusea e Vômito Pós-Operatórios/tratamento farmacológico , Náusea e Vômito Pós-Operatórios/epidemiologia , Náusea e Vômito Pós-Operatórios/prevenção & controle
6.
Elife ; 102021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33891544

RESUMO

In humans, intradermal administration of ß-alanine (ALA) and bovine adrenal medulla peptide 8-22 (BAM8-22) evokes the sensation of itch. Currently, it is unknown which human dorsal root ganglion (DRG) neurons express the receptors of these pruritogens, MRGPRD and MRGPRX1, respectively, and which cutaneous afferents these pruritogens activate in primate. In situ hybridization studies revealed that MRGPRD and MRGPRX1 are co-expressed in a subpopulation of TRPV1+ human DRG neurons. In electrophysiological recordings in nonhuman primates (Macaca nemestrina), subtypes of polymodal C-fiber nociceptors are preferentially activated by ALA and BAM8-22, with significant overlap. When pruritogens ALA, BAM8-22, and histamine, which activate different subclasses of C-fiber afferents, are administered in combination, human volunteers report itch and nociceptive sensations similar to those induced by a single pruritogen. Our results provide evidence for differences in pruriceptive processing between primates and rodents, and do not support the spatial contrast theory of coding of itch and pain.


Assuntos
Gânglios Espinais/fisiopatologia , Nociceptores/fisiologia , Fragmentos de Peptídeos/efeitos adversos , Prurido/fisiopatologia , Receptores Acoplados a Proteínas G/genética , beta-Alanina/efeitos adversos , Adulto , Animais , Feminino , Gânglios Espinais/efeitos dos fármacos , Histamina/administração & dosagem , Humanos , Macaca nemestrina/fisiologia , Masculino , Pessoa de Meia-Idade , Nociceptores/efeitos dos fármacos , Prurido/induzido quimicamente , Receptores Acoplados a Proteínas G/metabolismo , Adulto Jovem
7.
Pain ; 162(Suppl 1): S26-S44, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33729209

RESUMO

ABSTRACT: We report a systematic review and meta-analysis of studies that assessed the antinociceptive efficacy of cannabinoids, cannabis-based medicines, and endocannabinoid system modulators on pain-associated behavioural outcomes in animal models of pathological or injury-related persistent pain. In April 2019, we systematically searched 3 online databases and used crowd science and machine learning to identify studies for inclusion. We calculated a standardised mean difference effect size for each comparison and performed a random-effects meta-analysis. We assessed the impact of study design characteristics and reporting of mitigations to reduce the risk of bias. We meta-analysed 374 studies in which 171 interventions were assessed for antinociceptive efficacy in rodent models of pathological or injury-related pain. Most experiments were conducted in male animals (86%). Antinociceptive efficacy was most frequently measured by attenuation of hypersensitivity to evoked limb withdrawal. Selective cannabinoid type 1, cannabinoid type 2, nonselective cannabinoid receptor agonists (including delta-9-tetrahydrocannabinol) and peroxisome proliferator-activated receptor-alpha agonists (predominantly palmitoylethanolamide) significantly attenuated pain-associated behaviours in a broad range of inflammatory and neuropathic pain models. Fatty acid amide hydrolase inhibitors, monoacylglycerol lipase inhibitors, and cannabidiol significantly attenuated pain-associated behaviours in neuropathic pain models but yielded mixed results in inflammatory pain models. The reporting of criteria to reduce the risk of bias was low; therefore, the studies have an unclear risk of bias. The value of future studies could be enhanced by improving the reporting of methodological criteria, the clinical relevance of the models, and behavioural assessments. Notwithstanding, the evidence supports the hypothesis of cannabinoid-induced analgesia.


Assuntos
Canabinoides , Cannabis , Neuralgia , Analgésicos/uso terapêutico , Animais , Canabinoides/uso terapêutico , Endocanabinoides , Masculino , Modelos Animais , Neuralgia/tratamento farmacológico
8.
Dtsch Arztebl Int ; 117(49): 833-840, 2020 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-33593477

RESUMO

BACKGROUND: High-dose opioids are conventionally used for cardiac anesthesia, but without monitoring of nociception. In non-cardiac surgical procedures the intra - operative dose of opioids can be individualized and reduced with pupillometric monitoring of the pupillary pain index (PPI; scale 1-9). A randomized controlled trial was carried out to explore whether pupillometry can be used for nociception monitoring in cardiac anesthesia and whether it leads to opioid reduction. METHODS: A sample of 57 cardiac surgery patients receiving continuously administered sufentanil (initial dosage 0.7 µg*kg-¹*h-¹) was divided into a PPI group (sufentanil reduction if PPI<3 up to a minimum of 0.15 µg*kg-¹*h-¹, n=32) and a control group (standard anesthesia; n = 25). The primary outcome was the time from the end of anesthesia to extubation. The secondary outcomes were total intraoperative dose of sufentanil/noradrenaline, postoperative pain intensity (numeric rating scale [NRS] 0-10) and intraoperative awareness. German Clinical Trials Registry no. DRKS 00012329. RESULTS: The primary outcome, extubation time, did not differ between the two groups (1.14 h, 95% confidence interval [-0.99; 3.27], p = 0.592). Compared with the control patients (68% male, age 70 ± 10.4 years, PPI 1.1 ± 0.2), the mean sufentanil infusion rate in the PPI patients (81% male, age 68 ± 10.3 years, PPI 1.1 ± 0.2) decreased by 81.8% (-0.68 µg*kg-¹*h-¹ [-0,7; -0.67], p<0.001) to the predetermined minimum level, without intraoperative awareness. Moreover, the noradrenaline dose was reduced by 56% (1235.51 µg [321.91; 2149.12], p = 0.005) and the postoperative pain intensity by 45% (2.11 NRS [0.93; 3.3] after 24 h, p = 0.003). CONCLUSION: Pupillometry is appropriate for nociception monitoring in cardiac anesthesia. Thereby a considerable reduction of intraoperative opioids as well as increased intraoperative hemodynamic stability was achieved and postoperative opioid-induced hyperalgesia was prevented. The consistently low PPI scores, indicating adequate analgesia, suggest that further reduction of opioid doses is feasible.


Assuntos
Anestesia em Procedimentos Cardíacos , Nociceptividade , Idoso , Idoso de 80 Anos ou mais , Analgésicos Opioides , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dor Pós-Operatória/diagnóstico , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Estudos Prospectivos , Sufentanil
9.
JMIR Res Protoc ; 9(8): e15997, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32657759

RESUMO

BACKGROUND: Sepsis remains a major health challenge with high mortality. Adequate volume administration is fundamental for a successful outcome. However, individual fluid needs differ between patients due to varying degrees of systemic vasodilation, circulatory flow maldistribution, and increased vascular permeability. The current fluid resuscitation practice has been questioned. Fluid overload is associated with higher mortality in sepsis. A sign of fluid overload is extravascular lung water, seen as B lines in lung ultrasound. B lines correlate inversely with oxygenation (measured by a ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen ie, PaO2/FiO2). Thus, B lines seen by bedside ultrasound may have a role in guiding fluid therapy. OBJECTIVE: We aim to evaluate if fluid administration guided by lung ultrasound in patients with sepsis in emergency departments will lead to better oxygenation and patient outcomes than those in the standard therapy. METHODS: A phase II, multicenter, randomized, open-label, parallel-group, superiority trial will be performed. Patients will be recruited at emergency departments of the participating centers. A total of 340 patients will be randomly allocated to the intervention or standard-of-care group (30mL/kg). The intervention group will receive ultrasound-guided intravenous fluid until 3 B lines appear. The primary outcome will be oxygenation (measured as PaO2/FiO2 ratio) at 48 hours after starting intravenous fluid administration. Secondary outcomes will be patients' outcome parameters, including oxygenation after 15 mL/kg fluid at 6, 12, 24, and 48 hours; sepsis progress through Sequential Organ Failure Assessment (SOFA) scores; pulmonary edema evaluation; and 30-day mortality. RESULTS: The trial will be conducted in accordance with the Declaration of Helsinki. Institutional review board approval will be sought after the participating sites are selected. The protocol will be registered once the institutional review board approval is granted. The trial duration is expected to be 1.5-2.5 years. The study is planned to be performed from 2021 to 2022, with enrollment starting in 2021. First results are expected in 2022. Informed written consent will be obtained before the patient's enrollment in the study. An interim analysis and data monitoring will ensure the patient safety. The results will be published in a peer-reviewed journal and discussed at international conferences. CONCLUSIONS: This is a protocol for a randomized control trial that aims to evaluate the role of bedside ultrasound in guiding fluid therapy in patients with sepsis via B lines evaluation. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/15997.

10.
Cell Rep ; 31(9): 107704, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-32492420

RESUMO

Fast purinergic signaling is mediated by ATP and ATP-gated ionotropic P2X receptors (P2XRs), and it is implicated in pain-related behaviors. The properties exhibited by P2XRs vary between those expressed in heterologous cells and in vivo. Several modulators of ligand-gated ion channels have recently been identified, suggesting that there are P2XR functional modulators in vivo. Here, we establish a genome-wide open reading frame (ORF) collection and perform functional screening to identify modulators of P2XR activity. We identify TMEM163, which specifically modulates the channel properties and pharmacology of P2XRs. We also find that TMEM163 is required for full function of the neuronal P2XR and a pain-related ATP-evoked behavior. These results establish TMEM163 as a critical modulator of P2XRs in vivo and a potential target for the discovery of drugs for treating pain.


Assuntos
Trifosfato de Adenosina/farmacologia , Comportamento Animal/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Receptores Purinérgicos P2X/metabolismo , Animais , Cálcio/metabolismo , Potenciais Evocados/efeitos dos fármacos , Feminino , Genoma , Células HEK293 , Humanos , Proteínas de Membrana/antagonistas & inibidores , Proteínas de Membrana/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Fases de Leitura Aberta/genética , Dor/patologia , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Receptores Purinérgicos P2X/genética , Receptores Purinérgicos P2X3/deficiência , Receptores Purinérgicos P2X3/genética , Receptores Purinérgicos P2X3/metabolismo
11.
Sci Rep ; 9(1): 3148, 2019 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-30816253

RESUMO

DNA- and histone-related research frequently comprises the quantitative analysis of protein modifications, such as histone phosphorylation. Analysis of accumulation and disappearance of protein foci are used to monitor DNA damage and repair kinetics. If the protein of interest doesn't accumulate in foci, laser micro-irradiation of single nuclei provides an alternative method to monitor DNA repair proteins and histone dynamics at the DNA damage site. We have developed an automated evaluation tool for standardized, high-throughput analysis of micro-irradiated cells featuring single cell background subtraction and detection across multiple fluorescence channels, allowing for robust statistics.


Assuntos
Código das Histonas/genética , Histonas/genética , Processamento de Proteína Pós-Traducional/genética , Proteínas/genética , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Dano ao DNA/genética , Dano ao DNA/efeitos da radiação , Reparo do DNA/genética , Reparo do DNA/efeitos da radiação , Histonas/química , Humanos , Lasers/efeitos adversos , Microscopia de Fluorescência , Fosforilação/efeitos da radiação , Proteínas/química , Análise de Célula Única
12.
Pain Rep ; 4(5): e781, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31875186

RESUMO

INTRODUCTION: Irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD) are inflammatory skin diseases accompanied by itch and pain. Irritant contact dermatitis is caused by chemical irritants eliciting an innate immune response, whereas ACD is induced by haptens additionally activating an adaptive immune response: After initial exposure (sensitization) to the hapten, a subsequent challenge can lead to a delayed-type hypersensitivity reaction. But, the sensory and inflammatory effects of sensitization (ICD) vs challenge of ACD are insufficiently studied. Therefore, we compared itch- and pain-like behaviors and inflammatory reactions evoked in mice during the sensitization (ICD) vs challenge phase (ACD) of application of the hapten, squaric acid dibutylester (SADBE). OBJECTIVES: Our aim was to compare itch- and pain-like behaviors and inflammatory reactions evoked in mice during the sensitization (ICD) vs challenge phase (ACD) of application of the hapten, squaric acid dibutylester (SADBE). METHODS: Mice were sensitized on the abdomen with 1% SADBE (ACD) or vehicle treated (ICD, control). Spontaneous and stimulus-evoked itch- and pain-like behaviors were recorded in mice before and after 3 daily challenges of the cheek with 1% SADBE (ACD, ICD). Cutaneous inflammation was evaluated with clinical scoring, ultrasound imaging, skin thickness, histology, and analyses of selected biomarkers for contact dermatitis, IL-1ß, TNF-α, CXCL10, and CXCR3. RESULTS: Allergic contact dermatitis vs ICD mice exhibited more spontaneous site-directed scratching (itch) and wiping (pain). Allergic contact dermatitis-but not ICD-mice exhibited allodynia and hyperalgesia to mechanical and heat stimuli. Inflammatory mediators IL-1ß and TNF-α were upregulated in both groups as well as the chemokine receptor, CXCR3. CXCL10, a CXCR3 ligand, was upregulated only for ACD. Inflammatory responses were more pronounced in ACD than ICD. CONCLUSION: These findings provide new information for differentiating the behavioral and inflammatory reactions to hapten-induced ICD and ACD.

13.
Cancers (Basel) ; 10(3)2018 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-29562639

RESUMO

Genetic alterations driving aberrant activation of the survival kinase Protein Kinase B (Akt) are observed with high frequency during malignant transformation and cancer progression. Oncogenic gene mutations coding for the upstream regulators or Akt, e.g., growth factor receptors, RAS and phosphatidylinositol-3-kinase (PI3K), or for one of the three Akt isoforms as well as loss of the tumor suppressor Phosphatase and Tensin Homolog on Chromosome Ten (PTEN) lead to constitutive activation of Akt. By activating Akt, these genetic alterations not only promote growth, proliferation and malignant behavior of cancer cells by phosphorylation of various downstream signaling molecules and signaling nodes but can also contribute to chemo- and radioresistance in many types of tumors. Here we review current knowledge on the mechanisms dictating Akt's activation and target selection including the involvement of miRNAs and with focus on compartmentalization of the signaling network. Moreover, we discuss recent advances in the cross-talk with DNA damage response highlighting nuclear Akt target proteins with potential involvement in the regulation of DNA double strand break repair.

14.
Radiat Res ; 188(1): 114-120, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28492345

RESUMO

The quantitative analysis of foci plays an important role in various cell biological methods. In the fields of radiation biology and experimental oncology, the effect of ionizing radiation, chemotherapy or molecularly targeted drugs on DNA damage induction and repair is frequently performed by the analysis of protein clusters or phosphorylated proteins recruited to so called repair foci at DNA damage sites, involving for example γ-H2A.X, 53BP1 or RAD51. We recently developed "The Focinator" as a reliable and fast tool for automated quantitative and qualitative analysis of nuclei and DNA damage foci. The refined software is now even more user-friendly due to a graphical interface and further features. Thus, we included an R-script-based mode for automated image opening, file naming, progress monitoring and an error report. Consequently, the evaluation no longer required the attendance of the operator after initial parameter definition. Moreover, the Focinator v2-0 is now able to perform multi-channel analysis of four channels and evaluation of protein-protein colocalization by comparison of up to three foci channels. This enables for example the quantification of foci in cells of a specific cell cycle phase.


Assuntos
Pontos de Checagem do Ciclo Celular/efeitos da radiação , Gráficos por Computador , Dano ao DNA/genética , Microscopia de Fluorescência/métodos , Software , Interface Usuário-Computador , Células A549 , Algoritmos , Núcleo Celular/efeitos da radiação , Núcleo Celular/ultraestrutura , Citometria de Fluxo/métodos , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Linguagens de Programação
15.
Radiat Oncol ; 10: 163, 2015 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-26238507

RESUMO

BACKGROUND: The quantitative analysis of foci plays an important role in many cell biological methods such as counting of colonies or cells, organelles or vesicles, or the number of protein complexes. In radiation biology and molecular radiation oncology, DNA damage and DNA repair kinetics upon ionizing radiation (IR) are evaluated by counting protein clusters or accumulations of phosphorylated proteins recruited to DNA damage sites. Consistency in counting and interpretation of foci remains challenging. Many current software solutions describe instructions for time-consuming and error-prone manual analysis, provide incomplete algorithms for analysis or are expensive. Therefore, we aimed to develop a tool for costless, automated, quantitative and qualitative analysis of foci. METHODS: For this purpose we integrated a user-friendly interface into ImageJ and selected parameters to allow automated selection of regions of interest (ROIs) depending on their size and circularity. We added different export options and a batch analysis. The use of the Focinator was tested by analyzing γ-H2.AX foci in murine prostate adenocarcinoma cells (TRAMP-C1) at different time points after IR with 0.5 to 3 Gray (Gy). Additionally, measurements were performed by users with different backgrounds and experience. RESULTS: The Focinator turned out to be an easily adjustable tool for automation of foci counting. It significantly reduced the analysis time of radiation-induced DNA-damage foci. Furthermore, different user groups were able to achieve a similar counting velocity. Importantly, there was no difference in nuclei detection between the Focinator and ImageJ alone. CONCLUSIONS: The Focinator is a costless, user-friendly tool for fast high-throughput evaluation of DNA repair foci. The macro allows improved foci evaluation regarding accuracy, reproducibility and analysis speed compared to manual analysis. As innovative option, the macro offers a combination of multichannel evaluation including colocalization analysis and the possibility to run all analyses in a batch mode.


Assuntos
Adenocarcinoma/genética , Contagem de Células/instrumentação , Dano ao DNA , DNA de Neoplasias/efeitos da radiação , Ensaios de Triagem em Larga Escala/métodos , Histonas/análise , Processamento de Imagem Assistida por Computador/métodos , Proteínas de Neoplasias/análise , Neoplasias da Próstata/genética , Software , Adenocarcinoma/química , Adenocarcinoma/patologia , Algoritmos , Animais , Automação , Carbocianinas , DNA de Neoplasias/análise , Apresentação de Dados , Técnica Direta de Fluorescência para Anticorpo , Corantes Fluorescentes , Histonas/genética , Masculino , Camundongos , Microscopia de Fluorescência , Neoplasias da Próstata/química , Neoplasias da Próstata/patologia , Reprodutibilidade dos Testes , Interface Usuário-Computador
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