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1.
Cereb Cortex ; 31(3): 1827-1836, 2021 02 05.
Article in English | MEDLINE | ID: mdl-33207366

ABSTRACT

Following birth, infants must immediately process and rapidly adapt to the array of unknown sensory experiences associated with their new ex-utero environment. However, although it is known that unimodal stimuli induce activity in the corresponding primary sensory cortices of the newborn brain, it is unclear how multimodal stimuli are processed and integrated across modalities. The latter is essential for learning and understanding environmental contingencies through encoding relationships between sensory experiences; and ultimately likely subserves development of life-long skills such as speech and language. Here, for the first time, we map the intracerebral processing which underlies auditory-sensorimotor classical conditioning in a group of 13 neonates (median gestational age at birth: 38 weeks + 4 days, range: 32 weeks + 2 days to 41 weeks + 6 days; median postmenstrual age at scan: 40 weeks + 5 days, range: 38 weeks + 3 days to 42 weeks + 1 days) with blood-oxygen-level-dependent (BOLD) functional magnetic resonance imaging (MRI) and magnetic resonance (MR) compatible robotics. We demonstrate that classical conditioning can induce crossmodal changes within putative unimodal sensory cortex even in the absence of its archetypal substrate. Our results also suggest that multimodal learning is associated with network wide activity within the conditioned neural system. These findings suggest that in early life, external multimodal sensory stimulation and integration shapes activity in the developing cortex and may influence its associated functional network architecture.


Subject(s)
Cerebral Cortex/physiology , Infant, Newborn/physiology , Learning/physiology , Acoustic Stimulation , Brain Mapping/methods , Conditioning, Classical , Female , Humans , Magnetic Resonance Imaging/methods , Male
2.
Cereb Cortex ; 28(7): 2507-2515, 2018 07 01.
Article in English | MEDLINE | ID: mdl-29901788

ABSTRACT

In the mature mammalian brain, the primary somatosensory and motor cortices are known to be spatially organized such that neural activity relating to specific body parts can be somatopically mapped onto an anatomical "homunculus". This organization creates an internal body representation which is fundamental for precise motor control, spatial awareness and social interaction. Although it is unknown when this organization develops in humans, animal studies suggest that it may emerge even before the time of normal birth. We therefore characterized the somatotopic organization of the primary sensorimotor cortices using functional MRI and a set of custom-made robotic tools in 35 healthy preterm infants aged from 31 + 6 to 36 + 3 weeks postmenstrual age. Functional responses induced by somatosensory stimulation of the wrists, ankles, and mouth had a distinct spatial organization as seen in the characteristic mature homunculus map. In comparison to the ankle, activation related to wrist stimulation was significantly larger and more commonly involved additional areas including the supplementary motor area and ipsilateral sensorimotor cortex. These results are in keeping with early intrinsic determination of a somatotopic map within the primary sensorimotor cortices. This may explain why acquired brain injury in this region during the preterm period cannot be compensated for by cortical reorganization and therefore can lead to long-lasting motor and sensory impairment.


Subject(s)
Afferent Pathways/physiology , Brain Mapping , Premature Birth/pathology , Sensorimotor Cortex/growth & development , Sensorimotor Cortex/pathology , Age Factors , Ankle/innervation , Female , Functional Laterality , Humans , Image Processing, Computer-Assisted , Infant , Infant, Premature , Magnetic Resonance Imaging , Male , Mouth/innervation , Oxygen/blood , Physical Stimulation , Premature Birth/physiopathology , Sensorimotor Cortex/diagnostic imaging , Wrist/innervation
3.
Anaesthesist ; 59(4): 333-41, 2010 Apr.
Article in German | MEDLINE | ID: mdl-20224948

ABSTRACT

BACKGROUND: In the medical literature the Lazarus phenomenon is defined as the spontaneous return of circulation (SROC) after cessation of cardio-pulmonary resuscitation. Based on published literature recommendations concerning the treatment of patients after cessation of resuscitation and reasons for the Lazarus phenomenon are discussed. METHODS: A literature search in Medline, PubMed, Embase, Google Scholar and Google from 1982 to 2009 was carried out for the terms "Lazarus phenomenon", "cessation of cardiopulmonary resuscitation and return of spontaneous circulation (ROSC)", "spontaneous return of circulation (SROC)", "resuscitation and spontaneous defibrillation", "spontaneous recovery and cardiopulmonary resuscitation". Related secondary literature which was cited in the relevant articles was included as well as publications found in our personal literature base. RESULTS: More than 10,000 articles and comments could be recovered and of these 45 were considered to be medically relevant articles (letters to the Editor, abstracts, case reports and literature reviews). CONCLUSIONS: In the relevant medical literature, the Lazarus phenomenon is a rare occurrence. It seems to be a phenomenon which has often been described in non-medical literature but not published in medical literature. The pathophysiological mechanisms are poorly understood. In the literature several mechanisms are discussed which could be important for this phenomenon, e.g. autopositive end-expiratory pressure, hyperventilation and alkalosis, hyperkalemia, delayed action of drugs and unobserved minimal vital signs. In the literature it is recommended that patients should be passively monitored for at least 10 min after cessation of resuscitation. However, more scientific experimental investigations seem to be necessary to gain a better understanding of this phenomenon.


Subject(s)
Cardiopulmonary Resuscitation , Heart Arrest/physiopathology , Adult , Aged , Aged, 80 and over , Databases, Factual , Death , Female , Humans , Male , Middle Aged , Remission, Spontaneous
4.
Anaesthesist ; 59(2): 162-70, 2010 Feb.
Article in German | MEDLINE | ID: mdl-20127061

ABSTRACT

BACKGROUND: In Germany, specialized out-patient palliative care systems (SPCS) are still structurally and organizationally under construction. Palliative care patients need an easy access to a qualified SPCS. The purpose of the present investigation was to show the nationwide distribution of all SPCS teams in comparison to the distribution of emergency medical systems. Possibilities for an effective structure of palliative medical care systems will be discussed in order to optimize patient care.. METHODS: All SPCS teams in Germany (according to the Guide to hospices and palliative medicine of the German Association for Palliative Care 2008/2009) were documented. A cartographic representation of the structural distribution of palliative care systems was made taking a catchment area diameter of 50 km for each SPCS team and an accessibility diameter of 20 km for every palliative ward into account. These data were compared with the nationwide distribution of emergency institutions. RESULTS: In Germany 25 SPCS teams and 198 palliative wards could be identified. In contrast there are 1,109 emergency physician locations (1,051 ground based, 58 air based). The nationwide distribution of the existing SPCS teams does not at present give exhaustive coverage in comparison to emergency medical structures. No structure which might potentially result in an exhaustive implementation of SPCS teams and palliative stations is recognizable in the analysis or distribution. CONCLUSIONS: The coverage of SPCS and in-hospital palliative care is still a theoretical construct in many regions of Germany. The number of existing SPCS teams and in-patient palliative institutions is insufficient to guarantee an exhaustive coverage of patient care as in emergency medical services. In order to achieve a higher quality of results the quality of the structure and processes must first be ensured. The distribution of palliative care should be centrally coordinated along the same lines as the emergency institutions in order to achieve a need-oriented exhaustive coverage. A surplus of care in some regions at the expense of an undersupply in other regions must be avoided. In the next step a further development and adaption of existing structures to the requirements would be a logical approach.


Subject(s)
Emergency Medical Services/organization & administration , Palliative Care/organization & administration , Ambulatory Care , Emergency Medical Services/standards , Emergency Medical Services/statistics & numerical data , Germany , Health Care Surveys , Hospices/organization & administration , Hospices/standards , Hospital Departments , Hospitalization , Humans , Palliative Care/statistics & numerical data , Patient Care Team/organization & administration , Societies, Medical
5.
Oncogene ; 26(15): 2212-9, 2007 Apr 02.
Article in English | MEDLINE | ID: mdl-17401430

ABSTRACT

Inactivation of tumor-suppressor genes is one of the key hallmarks of a tumor. Unlike other tumor-suppressor genes, p53 is inactivated by missense mutations in half of all human cancers. It has become increasingly clear that the resulting mutant p53 proteins do not represent only the mere loss of wild-type p53 tumor suppressor activity, but gain new oncogenic properties favoring the insurgence, the maintenance, the spreading and the chemoresistance of malignant tumors. The actual challenge is the fine deciphering of the molecular mechanisms underlying the gain of function of mutant p53 proteins. In this review, we will focus mainly on the transcriptional activity of mutant p53 proteins as one of the potential molecular mechanisms. To date, the related knowledge is still quite scarce and many of the raised questions of this review are yet unanswered.


Subject(s)
Neoplasms/genetics , Oncogenes , Transcription Factors/genetics , Transcription Factors/metabolism , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Humans , Mutation
6.
Nano Lett ; 6(9): 2026-30, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16968020

ABSTRACT

Nanoparticles are essential building blocks for nanotechnology. In this paper we demonstrate a novel method to create nanoplatelets by thin film cracking. The thickness of the resulting platelets is determined by the film thickness, and their aspect ratio is controlled by the total strain and the elastic mismatch between substrate and thin film. Platelets can be created from any brittle film independently of microstructure and materials class. The feasibility of this method is substantiated by a statistical analysis of the fracture process.


Subject(s)
Membranes, Artificial , Models, Chemical , Models, Molecular , Nanotubes/chemistry , Nanotubes/ultrastructure , Computer Simulation , Elasticity , Feasibility Studies , Models, Statistical , Molecular Conformation , Particle Size , Stress, Mechanical
7.
Int J Syst Evol Microbiol ; 50 Pt 2: 781-785, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10758889

ABSTRACT

The closer proximity of Frankia and Acidothermus cellulolyticus relative to the morphologically close Geodermatophilus found previously was confirmed by resequencing the rrs gene of Acidothermus cellulolyticus and the housekeeping gene, recA. The diagnostic sugar 2-O-methyl-D-mannose was detected only in Frankia, while hopanoid lipids were present at high levels in both Acidothermus and Frankia.


Subject(s)
Actinomycetales/classification , Actinomycetales/genetics , Genes, rRNA , Phylogeny , Rec A Recombinases/genetics , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Lipid Metabolism , Molecular Sequence Data , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
8.
Br J Rheumatol ; 35 Suppl 1: 61-7, 1996 Apr.
Article in English | MEDLINE | ID: mdl-8630640

ABSTRACT

Meloxicam is a new non-steroidal anti-inflammatory drug (NSAID) which preferentially inhibits cyclooxygenase-2 (COX-2) over cyclooxygenase-1 (COX-1). Gastrointestinal (GI) tolerability of meloxicam 7.5 and 15 mg vs piroxicam 20 mg was evaluated in a 4-week, double-blind, parallel group, placebo-controlled study in 51 healthy male volunteers, using a combination of oesphago-gastro-duodenal endoscopy, faecal blood loss measurement and symptom evaluation. Analysis of covariance found no significant difference in faecal blood loss between the groups. However, significantly higher bleeding was found with piroxicam 20 mg compared with placebo using a Student's t-test on the weighted means. Endoscopy score were significantly higher with piroxicam than with meloxicam 7.5 mg or placebo (P < 0.01). A significant difference from baseline was observed in the meloxicam 15 mg and piroxicam groups (P < 0.05), but not in the meloxicam 7.5 mg and placebo groups. Six piroxicam-treated volunteers were withdrawn following a poor endoscopic score, but no such withdrawals occurred in the meloxicam and placebo groups (P < 0.01). Meloxicam 7.5 mg caused less GI damage compared with piroxicam 20 when administered to healthy young volunteers for 28 days; a possible dose dependency effect in GI tolerability was also suggested for meloxicam 7.5 and 15 mg, in relation to endoscopic findings.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Digestive System/drug effects , Piroxicam/adverse effects , Thiazines/adverse effects , Thiazoles/adverse effects , Adult , Anti-Inflammatory Agents, Non-Steroidal/administration & dosage , Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Digestive System/anatomy & histology , Double-Blind Method , Drug Evaluation , Drug Tolerance , Endoscopy, Gastrointestinal , Humans , Male , Meloxicam , Occult Blood , Piroxicam/administration & dosage , Piroxicam/pharmacology , Thiazines/administration & dosage , Thiazines/pharmacology , Thiazoles/administration & dosage , Thiazoles/pharmacology , Time Factors
9.
Int J Syst Bacteriol ; 46(1): 1-9, 1996 Jan.
Article in English | MEDLINE | ID: mdl-8573482

ABSTRACT

The members of the actinomycete genus Frankia are nitrogen-fixing symbionts of may species of woody dicotyledonous plants belonging to eight families. Several strains isolated from diverse actinorhizal plants growing in different geographical areas were used in this study. The phylogenetic relationships of these organisms and uncharacterized microsymbionts that are recalcitrant to isolation in pure culture were determined by comparing complete 16S ribosomal DNA sequences. The resulting phylogenetic tree revealed that there was greater diversity among the Alnus-infective strains than among the strains that infect other host plants. The four main subdivisions of the genus Frankia revealed by this phylogenetic analysis are (i) a very large group comprising Frankia alni and related organisms (including Alnus rugosa Sp+ microsymbionts that are seldom isolated in pure culture), to which Casuarina-infective strains, a Myrica nagi microsymbiont, and other effective Alnus-infective strains are related; (ii) unisolated microsymbionts of Dryas, Coriaria, and Datisca species; (iii) Elaeagnus-infective strains; and (iv) "atypical" strains (a group which includes an Alnus-infective, non-nitrogen-fixing strain). Taxa that are related to this well-defined, coherent Frankia cluster are the genera Geodermatophilus, "Blastococcus," Sporichthya, Acidothermus, and Actinoplanes. However, the two genera whose members have multilocular sporangia (the genera Frankia and Geodermatophilus) did not form a coherent group. For this reason, we propose that the family Frankiaceae should be emended so that the genera Geodermatophilus and "Blastococcus" are excluded and only the genus Frankia is retained.


Subject(s)
Actinomycetales/classification , Phylogeny , Actinomycetales/genetics , Base Sequence , Chromosomes, Bacterial , DNA, Bacterial/genetics , DNA, Ribosomal/genetics , Molecular Sequence Data , Polymerase Chain Reaction , RNA, Bacterial/genetics , RNA, Ribosomal, 16S/genetics
10.
Psychopharmacology (Berl) ; 120(3): 237-43, 1995 Aug.
Article in English | MEDLINE | ID: mdl-8524969

ABSTRACT

The standardized scoring criteria of sleep can serve as a rough tool for monitoring the effects of psychoactive compounds, both in normal sleepers and in insomniac patients. More sensitive information on the impact of perturbing factors and drugs during sleep is supplied by the cyclic alternating pattern (CAP) parameters. In particular, CAP rate, which measures the amount of arousal instability during NREM sleep, has been proved of high reliability in a variety of clinical and pharmacological settings. The present study aimed at evaluating the activity of brotizolam (Br) 0.25 mg and triazolam (Tr) 0.25 mg on both conventional and CAP parameters in a model of situational insomnia of intermediate severity. Six middle-aged healthy subjects (three males and three females, aged 40-55 years) with no complaints about sleep, underwent a polysomnographic investigation according to a double-blind crossover design: placebo without noise (night 1), placebo with noise (night 2), brotizolam or triazolam without noise (nights 3 and 5), brotizolam or triazolam with noise (nights 4 and 6). The unperturbed nights consisted of standard recording conditions in a sound-protected sleep laboratory, whereas situational insomnia was accomplished by means of continuous white noise at 55 dBA delivered throughout the night. Subjects received medication orally at bedtime. An interval of at least 48 h was secured between consecutive recordings in the same individual. Compared to baseline conditions, situational insomnia was characterized by a shorter amount of total sleep (-40 min) and by an extension of intrasleep awakenings (+62 min).(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Azepines/therapeutic use , Hypnotics and Sedatives/therapeutic use , Sleep Initiation and Maintenance Disorders/drug therapy , Triazolam/therapeutic use , Adult , Animals , Cricetinae , Electroencephalography , Female , Humans , Male , Middle Aged , Placebo Effect , Psychiatric Status Rating Scales , Sleep Wake Disorders/drug therapy
11.
Int J Syst Bacteriol ; 44(1): 83-6, 1994 Jan.
Article in English | MEDLINE | ID: mdl-8123564

ABSTRACT

The phylogeny of bacteria belonging to the genus Nitrobacter was investigated by sequencing the whole 16S rRNA gene. The average level of similarity for the three Nitrobacter strains examined was high (99.2%), and the similarity level between Nitrobacter winogradskyi and Nitrobacter sp. strain LL, which represent two different genomic species, was even higher (99.6%). When all of the Nitrobacter strains and their phylogenetic neighbors Bradyrhizobium and Rhodopseudomonas species were considered, the average similarity level was 98.1%. When complete sequences were used, Nitrobacter hamburgensis clustered with the two other Nitrobacter strains, while this was not the case when partial sequences were used. The two Rhodopseudomonas palustris strains examined exhibited a low similarity level (97.6%) and were not clustered.


Subject(s)
Nitrobacter/classification , Phylogeny , Base Sequence , Molecular Sequence Data , Nitrobacter/genetics , Nucleic Acid Hybridization , RNA, Ribosomal, 16S/genetics , Sequence Homology, Nucleic Acid
12.
Respiration ; 57(4): 233-8, 1990.
Article in English | MEDLINE | ID: mdl-2095605

ABSTRACT

In 10 patients who required extracorporeal circulation (ECC) during surgery, we studied the damage induced by surgery to the pulmonary surfactant and the effectiveness of ambroxol in preventing changes in the phospholipid pool. There were 5 control patients and 5 patients who were given 1 g/day of ambroxol on the 4 days prior to and the 4 days after surgery. To follow changes in phospholipid concentrations, bronchoalveolar lavage (BAL) was performed before surgery and 24 h and 8 days after ECC. Phospholipids were assayed in the BAL liquid by two-dimensional thin-layer chromatography. There were marked decreases in total phosphorus and quantitative alterations of individual phospholipid species in the surfactant of the control group, but not in the patients treated with ambroxol.


Subject(s)
Ambroxol/therapeutic use , Extracorporeal Circulation/adverse effects , Lung Diseases/prevention & control , Postoperative Complications/prevention & control , Pulmonary Surfactants/physiology , Adult , Bronchoalveolar Lavage Fluid/chemistry , Chromatography, Thin Layer , Humans , Male , Middle Aged , Phospholipids/analysis
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