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1.
Resuscitation ; 178: 63-68, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35870556

RESUMO

BACKGROUND: Recent guidelines suggest that coronary angiography (CAG) should be considered for out-of-hospital cardiac arrest (OHCA) survivors, including those without ST elevation (STE) and without shockable rhythms. However, there is no prospective data to support CAG for survivors with nonshockable rhythms and no STE post resuscitation. METHODS: This was a re-analysis of the PEARL study (randomized OHCA survivors without STE to early CAG versus not). Patients were subdivided by initial rhythm as nonshockable (Nsh) vs shockable (Sh). The primary outcome was coronary angiographic evidence of acute culprit lesion, with secondary outcomes being survival to hospital discharge and neurological recovery. RESULTS: The PEARL study included 99 patients with OHCA from a presumed cardiac etiology, 24 with nonshockable and 75 with shockable rhythms. There was no difference in the frequency of CAG between the two groups [71% (Nsh) and 75% (Sh); p = 0.79], presence of CAD [81% (Nsh) and 68% (sh); p = 0.37, or culprit lesions identified in each group [50% (Nsh) and 45% (Sh); p = 0.78. Nonshockable patients had worse discharge survival [33% (Nsh) vs 57% (Sh); p = 0.04] and those survived, had worse neurological recovery [30% (Nsh) vs 54% (Sh); p = 0.02] compared to shockable patients. CONCLUSIONS: OHCA survivors presenting with nonshockable rhythms and no STE post resuscitation had similar prevalence of culprit coronary lesions to those with shockable rhythms. CAG may be considered in patients with OHCA without STE regardless of initial presenting rhythm. There was no benefit of emergent CAG both in shockable and non-shockable rhythms.


Assuntos
Reanimação Cardiopulmonar , Parada Cardíaca Extra-Hospitalar , Arritmias Cardíacas , Angiografia Coronária , Humanos , Parada Cardíaca Extra-Hospitalar/terapia , Sobreviventes
2.
ACS Nano ; 14(11): 15241-15247, 2020 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-33119271

RESUMO

The hexagonal close packed surface of gold shows a 22 × 3 "herringbone" surface reconstruction which makes it unique among the (111) surfaces of all metals. This long-range energetically favored dislocation pattern appears in response to the strong tensile stress that would be present on the unreconstructed surface. Adsorption of molecular and atomic species can be used to tune this surface stress and lift the herringbone reconstruction. Here we show that herringbone reconstruction can be controllably lifted in ultrahigh vacuum at cryogenic temperatures by precise hot electron injection in the presence of hydrogen molecules. We use the sharp tip of a scanning tunneling microscope (STM) for charge carrier injection and characterization of the resulting chain nanostructures. By comparing STM images, rotational spectromicroscopy and ab initio calculations, we show that formation of gold atomic chains is associated with release of gold atoms from the surface, lifting of the reconstruction, dissociation of H2 molecules, and formation of surface hydrides. Gold hydrides grow in a zipper-like mechanism forming chains along the [11̅0] directions of the Au(111) surface and can be manipulated by further electron injection. Finally, we demonstrate that Au(111) terraces can be transformed with nearly perfect terrace selectivity over distances of hundreds of nanometers.

3.
Nature ; 583(7818): E32, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32665716

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

4.
Nature ; 582(7812): 375-378, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32555487

RESUMO

Imaging of biomolecules guides our understanding of their diverse structures and functions1,2. Real-space imaging at sub-nanometre resolution using cryo-electron microscopy has provided key insights into proteins and their assemblies3,4. Direct molecular imaging of glycans-the predominant biopolymers on Earth, with a plethora of structural and biological functions5-has not been possible so far6. The inherent glycan complexity and backbone flexibility require single-molecule approaches for real-space imaging. At present, glycan characterization often relies on a combination of mass spectrometry and nuclear magnetic resonance imaging to provide insights into size, sequence, branching and connectivity, and therefore requires structure reconstruction from indirect information7-9. Here we show direct imaging of single glycan molecules that are isolated by mass-selective, soft-landing electrospray ion beam deposition and imaged by low-temperature scanning tunnelling microscopy10. The sub-nanometre resolution of the technique enables the visualization of glycan connectivity and discrimination between regioisomers. Direct glycan imaging is an important step towards a better understanding of the structure of carbohydrates.


Assuntos
Polissacarídeos/análise , Polissacarídeos/química , Imagem Individual de Molécula , Manosídeos/análise , Manosídeos/química , Microscopia de Tunelamento
5.
Science ; 367(6476): 411-415, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31727858

RESUMO

Nanoelectronic devices operating in the quantum regime require coherent manipulation and control over electrons at atomic length and time scales. We demonstrate coherent control over electrons in a tunnel junction of a scanning tunneling microscope by means of precise tuning of the carrier-envelope phase of two-cycle long (<6-femtosecond) optical pulses. We explore photon and field-driven tunneling, two different regimes of interaction of optical pulses with the tunnel junction, and demonstrate a transition from one regime to the other. Our results show that it is possible to induce, track, and control electronic current at atomic scales with subfemtosecond resolution, providing a route to develop petahertz coherent nanoelectronics and microscopy.

6.
Resuscitation ; 144: 131-136, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31580910

RESUMO

AIM: Each minute is crucial in the treatment of out-of-hospital cardiac arrest (CA). Immediate chest compressions and early defibrillation are keys to good outcomes. We hypothesized that a coordinated effort of alerting trained local neighborhood volunteers (vols) simultaneously with 911 activation of professional EMS providers would result in substantial decreases in call-to-arrival times, leading to earlier CPR and defibrillation. METHODS: We developed a program of simultaneously alerting CPR- and AED-trained neighborhood vols and the local EMS system for CA events in a retirement residential neighborhood in Southern Arizona, encompassing approximately 440 homes. The closest EMS station is 3.3 miles from this neighborhood. Within this neighborhood, 15 vols and the closest EMS station were involved in multiple days of mock CA notifications and responses. RESULTS: The two groups differed significantly in distance to the mock CA event and in response times. The volunteers averaged 0.3 ±â€¯0.2 miles from the mock CA incidences while the closest EMS station averaged 3.4 ±â€¯0.1 miles away (p < 0.0001). Response times (time from call to arrival) also differed. Two volunteers, one bringing an AED, averaged 1 min 38 s ±â€¯53 s in Phase 1, while it took the EMS service an average of 7 min 20 s ±â€¯1 min 13 s to arrive on scene; p < 0.0001. CONCLUSION: Local neighborhood volunteers were geographically closer and arrived significantly sooner at the mock CA scene than did the EMS service. The approximate time savings from call to arrival with the volunteers was 4-6 min.


Assuntos
Parada Cardíaca Extra-Hospitalar/terapia , Características de Residência , Tempo para o Tratamento , Voluntários , Idoso , Idoso de 80 Anos ou mais , Arizona , Reanimação Cardiopulmonar/educação , Serviços Médicos de Emergência/organização & administração , Feminino , Humanos , Masculino , Estudos Prospectivos , Treinamento por Simulação/métodos
7.
Orthopade ; 48(4): 348-349, 2019 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-30937485
9.
Chem Commun (Camb) ; 55(12): 1793-1796, 2019 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-30667016

RESUMO

In this work, a Mg(0001) single crystal is used as a novel template to grow 2D supramolecular nano-architectures. By using scanning tunnelling microscopy (STM) and high-resolution X-ray photoemission spectroscopy (HR-XPS), the formation of either a homo-molecular or metal-organic network is reported for carboxylic or amino functionalized molecules, respectively.

10.
Schmerz ; 32(6): 464-467, 2018 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-30306307

RESUMO

A 68-year-old patient suffered from postzoster neuralgia with severe pain of the left trigeminal nerve V1. Despite medication with gabapentin 1800 mg/d, oxacarbazepine 600 mg, tapentadol 500 mg/d, amitriptyline 20 mg as well as ambroxol 20% ointment and lidocaine patch topically, the pain reached an intensity of 8-10 on the numeric rating scale (NRS). Wearing a CPAP (continuous positive airway pressure) mask at night to treat a sleep apnea was impossible or the mask was leaking under lidocaine patch, only topical ambroxol 20% brought a certain pain relief. Lack of sleep, a strongly reduced quality of life and massive exhaustion followed quickly. Due to a fall the systemic medication could not be increased. Also lidocaine infusions with dexamethasone and supraorbitalis blockades were unsuccessful, and a ganglionic local opioid analgesia (GLOA) was anatomically not feasible. Therefore, 8 weeks after the onset of the disease, treatment with capsaicin 8% for 60 min on the face was performed. After only one week, 20-30% pain relief was achieved, sometimes even freedom from pain. Six weeks after application, the average pain during the day was only NRS 3/10 despite a considerable reduction in oral medication. Three months after the second treatment, the patient was almost pain-free during the day. Topical capsaicin 8% patch is, in our opinion, also safe and successful to use on the face with appropriate experience of the user.


Assuntos
Neuralgia Pós-Herpética , Idoso , Capsaicina , Humanos , Lidocaína , Qualidade de Vida , Nervo Trigêmeo
11.
Curr Cardiol Rev ; 14(2): 78, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30003855
12.
Resuscitation ; 128: 188-190, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29679697

RESUMO

"All citizens of the world can save a life". With these words, the International Liaison Committee on Resuscitation (ILCOR) is launching the first global initiative - World Restart a Heart (WRAH) - to increase public awareness and therefore the rates of bystander cardiopulmonary resuscitation (CPR) for victims of cardiac arrest. In most of the cases, it takes too long for the emergency services to arrive on scene after the victim's collapse. Thus, the most effective way to increase survival and favourable outcome in cardiac arrest by two- to fourfold is early CPR by lay bystanders and by "first responders". Lay bystander resuscitation rates, however, differ significantly across the world, ranging from 5 to 80%. If all countries could have high lay bystander resuscitation rates, this would help to save hundreds of thousands of lives every year. In order to achieve this goal, all seven ILCOR councils have agreed to participate in WRAH 2018. Besides schoolchildren education in CPR ("KIDS SAVE LIVES"), many other initiatives have already been developed in different parts of the world. ILCOR is keen for the WRAH initiative to be as inclusive as possible, and that it should happen every year on 16 October or as close to that day as possible. Besides recommending CPR training for children and adults, it is hoped that a unified global message will enable our policy makers to take action to address the inequalities in patient survival around the world.


Assuntos
Reanimação Cardiopulmonar/educação , Promoção da Saúde , Parada Cardíaca Extra-Hospitalar/terapia , Adulto , Criança , Saúde Global , Humanos , Parada Cardíaca Extra-Hospitalar/mortalidade , Tempo para o Tratamento
13.
Nanoscale ; 10(10): 4952-4961, 2018 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-29485651

RESUMO

Aberration-corrected high-resolution transmission electron microscopy (AC-HRTEM) has enabled atomically resolved imaging of molecules adsorbed on low-dimensional materials like carbon nanotubes, graphene oxide and few-layer-graphene. However, conventional methods for depositing molecules onto such supports lack selectivity and specificity. Here, we describe the chemically selective preparation and deposition of molecules-like polyoxometalate (POM) anions [PW12O40]3- using electrospray ion-beam deposition (ES-IBD) along with high-resolution TEM imaging. This approach provides access to sub-monolayer coatings of intact molecules on freestanding graphene, which enables their atomically resolved ex situ characterization by low-voltage AC-HRTEM. The capability to tune the deposition parameters in either soft or reactive landing mode, combined with the well-defined high-vacuum deposition conditions, renders the ES-IBD based method advantageous over alternative methods such as drop-casting. Furthermore, it might be expanded towards depositing and imaging large and nonvolatile molecules with complex structures.

14.
Chem Commun (Camb) ; 53(83): 11430-11432, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-28975932

RESUMO

A Scanning Tunneling Microscope (STM) is used to induce a reversible transition between different polymorphs in a binary supramolecular network at the liquid/solid interface. The transition is driven externally by switching the polarity of the sample by positive or negative sample bias potentials. We demonstrate that by mixing bias-sensitive and non-sensitive molecules, we gain access to a variety of binary porous structures that can be prepared and reliably actuated for each relative concentration.

15.
Curr Med Res Opin ; 33(8): 1401-1411, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28436279

RESUMO

BACKGROUND AND OBJECTIVE: The treatment of neuropathic pain due to low-back (lumbosacral) radiculopathies, a common source of neuropathic pain, is challenging and often requires a multimodal therapeutic approach. The capsaicin 8% patch is the first topical analgesic licensed for peripheral neuropathic pain. To evaluate this treatment, a subset of patients with painful radiculopathy (lumbar and cervical, including ventral and dorsal rami) enrolled into the multicenter, non-interventional QUEPP study (Qutenza 2 - safety and effectiveness in peripheral neuropathic pain) was analyzed. METHODS: Of the 1044 study participants, 50 were diagnosed with painful radiculopathy as only peripheral neuropathic pain syndrome and were eligible for evaluation. Patients received a single treatment (visit 1) with follow-up visits 2-5 at weeks 1-2, 4, 8 and 12. Parameters assessed at all visits included pain intensity, neuropathy symptoms and side effects. Quality of life (SF-12) and painDETECT 1 questionnaires were completed at baseline and final visit. Data was analyzed by patch application site and duration of pain. RESULTS: Topical treatment led to a significant decrease of pain intensity between weeks 1/2 and week 12 versus baseline at the application sites representing dermatomes of ventral (N = 26) and dorsal rami (N = 13) of spinal nerves. A significant decline (p ≤ .001) of numeric pain rating scale scores was observed between weeks 1/2 following patch application and the end of observation (week 12) in the overall radiculopathy group (N = 50), and the groups with either 3 months to 2 years (N = 14) or >2 years (N = 23) duration of pain. Pain relief of at least 30% was observed in 50.0%, 71.4% and 39.1% of patients in the respective groups. Four patients experienced in total seven adverse drug reactions (application site pain or pruritus). CONCLUSION: Effective neuropathic pain relief was observed after patch application within the innervation territories of both dorsal and ventral branches of the spinal nerve. Further controlled randomized trials are indicated.


Assuntos
Capsaicina/uso terapêutico , Neuralgia/tratamento farmacológico , Qualidade de Vida , Radiculopatia/tratamento farmacológico , Administração Cutânea , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prurido/induzido quimicamente , Coluna Vertebral , Inquéritos e Questionários , Resultado do Tratamento
16.
Schmerz ; 29 Suppl 3: S89-96, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26589711

RESUMO

BACKGROUND: Neuropathic pain is difficult to treat, and the available options are often inadequate. The expectorant ambroxol also acts as a strong local anaesthetic and blocks sodium channels about 40 times more potently than lidocaine. It preferentially inhibits the channel subtype Nav 1.8, which is expressed especially in nociceptive C-fibres. In view of the low toxicity of ambroxol, it seemed reasonable to try using it for the treatment of neuropathic pain that failed to respond to other standard options. MATERIAL AND METHODS: The medical records of seven patients with severe neuropathic pain and pain reduction following topical ambroxol treatment are reported retrospectively. As standard therapies had not proved sufficient, a topical ambroxol 20% cream was repeatedly applied by the patients in the area of neuropathic pain. RESULTS: The reasons for neuropathic pain were postherpetic neuralgia (2 ×), mononeuropathy multiplex, phantom pain, deafferentation pain, postoperative neuralgia and foot neuropathy of unknown origin. The individual mean pain intensity reported was between 4 and 6/10 (NRS), maximum pain at 6-10/10 (NRS). The pain reduction achieved individually following ambroxol cream was 2-8 points (NRS) within 5-30 min and lasted for 3-8 h. Pain attacks were reduced in all five patients presenting with this problem. Four patients with no improvement after lidocaine 5% and one patient with no response to capsaicin 8% nevertheless experienced a pain reduction with topical ambroxol. No patient reported any side effects or skin changes during a treatment that has since been continued for up to 4 years. CONCLUSION: Ambroxol acts as a strong local anaesthetic and preferentially inhibits the nociceptively relevant sodium channel subtype Nav 1.8. For the first time, we report below on a relevant pain relief following topical ambroxol 20% cream in patients with neuropathic pain. In view of the positive side effect profile, the clinical benefit in patients with pain should be investigated further.


Assuntos
Ambroxol/administração & dosagem , Anestésicos Locais , Neuralgia/tratamento farmacológico , Administração Tópica , Adulto , Idoso , Aminas/administração & dosagem , Ácidos Cicloexanocarboxílicos/administração & dosagem , Esquema de Medicação , Quimioterapia Combinada , Feminino , Gabapentina , Humanos , Masculino , Pessoa de Meia-Idade , Neuralgia/diagnóstico , Medição da Dor/efeitos dos fármacos , Dor Pós-Operatória/tratamento farmacológico , Satisfação do Paciente , Estudos Retrospectivos , Ácido gama-Aminobutírico/administração & dosagem
17.
Schmerz ; 29(6): 632-40, 2015 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-26597641

RESUMO

BACKGROUND: Neuropathic pain is difficult to treat and available options are frequently not sufficient. The expectorant ambroxol also works as a strong local anesthetic and blocks sodium channels about 40 times more potently than lidocaine. Ambroxol preferentially inhibits the channel subtype Nav 1.8, which is expressed particularly in nociceptive C fibers. Due to the low toxicity, topical ambroxol seemed to represent a reasonable therapeutic attempt for treatment of neuropathic pain resistant to other standard options. MATERIALS AND METHODS: Medical records of 7 patients with severe neuropathic pain, in whom many attempts at treatment with approved substances were not sufficient or possible, are reported retrospectively. Patients were then treated with topical ambroxol 20% cream applied in the area of neuropathic pain. RESULTS: Causes of neuropathic pain were postherpetic neuralgia (2-×), mononeuropathy multiplex, phantom pain, deafferentation pain, postoperative neuralgia and an unclear allodynia of the foot. Mean pain intensity was reported as 4-6/10 on a numeric rating scale (NRS) and maximum pain intensity as 6-10/10. Pain reduction following ambroxol cream was 2-8 points (NRS) within 15-30 min and lasted 3-8 h. Pain attacks were reduced in all 5 patients presenting this problem. Topical ambroxol achieved pain reduction in 4 patients with no improvement after lidocaine 5% and 1 patient with no response to capsaicin 8%. No adverse events or skin changes have been observed, and the longest treatment duration is currently 4 years. CONCLUSION: Ambroxol acts as a strong local anesthetic and preferentially inhibits the nociceptive-relevant sodium channel subtype Nav 1.8. For the first time, we report relevant pain reduction following topical Ambroxol 20% cream in patients with neuropathic pain. Regarding the advantageous profile with rare side effects, the clinical benefit for pain patients should be further investigated.


Assuntos
Ambroxol/administração & dosagem , Neuralgia/tratamento farmacológico , Administração Tópica , Adulto , Idoso , Idoso de 80 Anos ou mais , Ambroxol/efeitos adversos , Capsaicina/administração & dosagem , Feminino , Humanos , Lidocaína/administração & dosagem , Assistência de Longa Duração , Masculino , Pessoa de Meia-Idade , Neuralgia/etiologia , Medição da Dor/efeitos dos fármacos , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/etiologia , Estudos Retrospectivos
19.
Nat Commun ; 6: 8461, 2015 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-26416705

RESUMO

Exciton creation and annihilation by charges are crucial processes for technologies relying on charge-exciton-photon conversion. Improvement of organic light sources or dye-sensitized solar cells requires methods to address exciton dynamics at the molecular scale. Near-field techniques have been instrumental for this purpose; however, characterizing exciton recombination with molecular resolution remained a challenge. Here, we study exciton dynamics by using scanning tunnelling microscopy to inject current with sub-molecular precision and Hanbury Brown-Twiss interferometry to measure photon correlations in the far-field electroluminescence. Controlled injection allows us to generate excitons in solid C60 and let them interact with charges during their lifetime. We demonstrate electrically driven single-photon emission from localized structural defects and determine exciton lifetimes in the picosecond range. Monitoring lifetime shortening and luminescence saturation for increasing carrier injection rates provides access to charge-exciton annihilation dynamics. Our approach introduces a unique way to study single quasi-particle dynamics on the ultimate molecular scale.

20.
Nanoscale ; 7(30): 12807-11, 2015 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-26051658

RESUMO

We show that individual, isolated graphene nanoribbons, created with a molecular synthetic approach, can be assembled on functionalised wafer surfaces treated with silanes. The use of surface groups with different hydrophobicities allows tuning the density of the ribbons and assessing the products of the polymerisation process.

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