USSR Space Life Sciences Digest, issue 1

The first issue of the bimonthly digest of USSR Space Life Sciences is presented. Abstracts are included for 49 Soviet periodical articles in 19 areas of aerospace medicine and space biology, published in Russian during the first quarter of 1985. Translated introductions and table of contents for nine Russian books on topics related to NASA's life science concerns are presented. Areas covered include: botany, cardiovascular and respiratory systems, cybernetics and biomedical data processing, endocrinology, gastrointestinal system, genetics, group dynamics, habitability and environmental effects, health and medicine, hematology, immunology, life support systems, man machine systems, metabolism, musculoskeletal system, neurophysiology, perception, personnel selection, psychology, radiobiology, reproductive system, and space biology. This issue concentrates on aerospace medicine and space biology

Association of symptoms of insomnia and sleep parameters among kidney transplant recipients

Objective: Insomnia complaints are frequent among kidney transplant (kTx) recipients and are associated with fatigue, depression, lower quality of life and increased morbidity. However, it is not known if subjective insomnia symptoms are associated with objective parameters of sleep architecture. Thus, we analyze the association between sleep macrostructure and EEG activity versus insomnia symptoms among kTx recipients. Methods: Participants (n1 = 100) were selected from prevalent adult transplant recipients (n0 = 1214) followed at a single institution. Insomnia symptoms were assessed by the Athens Insomnia Scale (AIS) and standard overnight polysomnography was performed. In a subgroup of patients (n2 = 56) sleep microstructure was also analyzed with power spectral analysis. Results: In univariable analysis AIS score was not associated with sleep macrostructure parameters (sleep latency, total sleep time, slow wave sleep, wake after sleep onset), nor with NREM and REM beta or delta activity in sleep microstructure. In multivariable analysis after controlling for covariables AIS score was independently associated with the proportion of slow wave sleep (β = 0.263; CI: 0.026–0.500) and REM beta activity (β = 0.323; CI = 0.041–0.606) (p < 0.05 for both associations). Conclusions: Among kTx recipients the severity of insomnia symptoms is independently associated with higher proportion of slow wave sleep and increased beta activity during REM sleep but not with other parameters sleep architecture. The results suggest a potential compensatory sleep protective mechanism and a sign of REM sleep instability associated with insomnia symptoms among this population

Opioid dependence: brain structure and function : a magnetic resonance imaging, neuropsychological, and electromagnetic study

Background: Opiod dependence is a chronic severe brain disorder associated with enormous health and social problems. The relapse back to opioid abuse is very high especially in early abstinence, but neuropsychological and neurophysiological deficits during opioid abuse or soon after cessation of opioids are scarcely investigated. Also the structural brain changes and their correlations with the length of opioid abuse or abuse onset age are not known. In this study the cognitive functions, neural basis of cognitive dysfunction, and brain structural changes was studied in opioid-dependent patients and in age and sex matched healthy controls. Materials and methods: All subjects participating in the study, 23 opioid dependents of whom, 15 were also benzodiazepine and five cannabis co-dependent and 18 healthy age and sex matched controls went through Structured Clinical Interviews (SCID) to obtain DSM-IV axis I and II diagnosis and to exclude psychiatric illness not related to opioid dependence or personality disorders. Simultaneous magnetoencephalography (MEG) and electroencephalography (EEG) measurements were done on 21 opioid-dependent individuals on the day of hospitalization for withdrawal therapy. The neural basis of auditory processing was studied and pre-attentive attention and sensory memory were investigated. During the withdrawal 15 opioid-dependent patients participated in neuropsychological tests, measuring fluid intelligence, attention and working memory, verbal and visual memory, and executive functions. Fifteen healthy subjects served as controls for the MEG-EEG measurements and neuropsychological assessment. The brain magnetic resonance imaging (MRI) was obtained from 17 patients after approximately two weeks abstinence, and from 17 controls. The areas of different brain structures and the absolute and relative volumes of cerebrum, cerebral white and gray matter, and cerebrospinal fluid (CSF) spaces were measured and the Sylvian fissure ratio (SFR) and bifrontal ratio were calculated. Also correlation between the cerebral measures and neuropsychological performance was done. Results: MEG-EEG measurements showed that compared to controls the opioid-dependent patients had delayed mismatch negativity (MMN) response to novel sounds in the EEG and P3am on the contralateral hemisphere to the stimulated ear in MEG. The equivalent current dipole (ECD) of N1m response was stronger in patients with benzodiazepine co-dependence than those without benzodiazepine co-dependence or controls. In early abstinence the opioid dependents performed poorer than the controls in tests measuring attention and working memory, executive function and fluid intelligence. Test results of the Culture Fair Intelligence Test (CFIT), testing fluid intelligence, and Paced Auditory Serial Addition Test (PASAT), measuring attention and working memory correlated positively with the days of abstinence. MRI measurements showed that the relative volume of CSF was significantly larger in opioid dependents, which could also be seen in visual analysis. Also Sylvian fissures, expressed by SFR were wider in patients, which correlated negatively with the age of opioid abuse onset. In controls the relative gray matter volume had a positive correlation with composite cognitive performance, but this correlation was not found in opioid dependents in early abstinence. Conclusions: Opioid dependents had wide Sylvian fissures and CSF spaces indicating frontotemporal atrophy. Dilatation of Sylvian fissures correlated with the abuse onset age. During early withdrawal cognitive performance of opioid dependents was impaired. While intoxicated the pre-attentive attention to novel stimulus was delayed and benzodiazepine co-dependence impaired sound detection. All these changes point to disturbances on frontotemporal areas.Huumeriippuvuus on krooninen aivosairaus, joka johtaa aineen jatkuvaan käyttöön huolimatta käytön aiheuttamista vakavista haitoista kaikilla elämän alueilla. Huumeriippuvuuteen liittyy myös huomattava huumeidenkäytön uusiutumisriski erityisesti varhaisen vieroituksen aikana, mutta vielä pitkänkin päihteettömän ajanjakson jälkeen. Tutkimuksen tavoitteena oli selvittää pitkäaikaisen opioidien (heroiini ja buprenorfiini) väärinkäytön vaikutusta aivojen rakenteeseen magneettikuvauksella ja toimintaan aivojen sähköisiä vasteita mittaavilla elektroenkefalografia (EEG) - ja magnetoenkefalografiatutkimuksilla (MEG). Lisäksi kognitiivista suoriutumista selvitettiin varhaisen vieroitushoidon aikana neuropsykologisilla testeillä. Tutkimukseen osallistui 23 opioidiriippuvaista henkilöä, joista 15 oli myös bentsodiatsepiiniriippuvaisia. Tutkittavilla oli vakava pitkäaikainen opioidiriippuvuus. Tutkittavien tuloksia verrattiin iältään ja sukupuoleltaan vastaavien terveiden henkilöiden tutkimustuloksiin. Kaikille tutkittaville tehtiin strukturoidut psykiatriset haastattelut, joilla pois suljettiin sellaiset psykiatriset sairaudet, jotka eivät liity päihteiden käyttöön tai persoonallisuushäiriöihin. Kaikilla opioidiriippuvaisilla oli persoonallisuushäiriöitä, mutta verro-keilla ei niitä todettu. Vieroitushoitoon tulopäivänä opioidiriippuvaisille tehtiin samanaikainen EEG-MEG mittaus, jossa tutkittiin kuulovasteita. Tahatonta tarkkavaisuutta tutkittiin ns. poikkeavuusnegatiivisuus vasteella (mismatch negativity, MMN) ja P3a vasteella. MEG-EEG mittauksessa potilailla olivat MMN vaste EEG mittauksessa ja P3a vaste MEG mittauksessa viivästyneet viitaten tahattoman tarkkaavaisuuden muutokseen. Näitä vasteita pidetään kognitiivisina, alkeellista työmuistia edustavina vasteina. Potilailla, joilla oli myös bentsodiatsepiiniriippuvuus, oli kuuloärsykkeen aiheuttama vaste voimistunut. Aineiden sekakäyttö siis lisäsi kuulovasteen muutoksia. Vieroitushoidon aikana 15 opioidiriippuvaiselle tehtiin laaja neuropsykologinen tutkimus, jolla selvitettiin joustavaa älykkyyttä, muistin eri osa-alueita ja toiminnan ohjausta. Neuro-psykologisessa testissä potilaat menestyivät verrokeita huonommin tarkkavaisuutta ja työmuistia (PASAT) sekä toiminnan ohjausta (RFFT) ja joustavaa älykkyyttä mittaavissa tes-teissä (CFIT). PASAT ja CFIT testien tulokset korreloivat positiivisesti vieroitushoidon kestoon. Opioidiriipuvaisten kokonaissuoriutuminen neuropsykologisissa testeissä vieroitusvaiheessa oli verrokeita vaatimattomampi. Kahden viikon vieroitushoitojakson lopussa 17 opioidiriippuvaista kävi aivojen 1,5 T magneettiikuvauksessa. Kuvista analysoitiin valkean ja harmaan aineen sekä aivoselkäydin-nestetilojen tilavuudet sekä tehtiin aivorakenteiden pinta-ala mittauksia ja laskettiin rakenteiden suhteita. Myös korrelaatiot eri tutkimustulosten ja päihdehistorian välille laskettiin. Aivojen magneettiikuvauksessa todettiin, että aivojen sivukammiot olivat laajemmat kuin verrokeilla. Opioidiriipuvaisilla Sylvian uurteet oli leveämmät suhteessa aivojen poikkimittaan kuin verrokeilla ja tämä suhde korreloi opioidien käytön aloitusikään. Löydös viittaa aivojen otsa- ja ohimolohkojen surkastumiseen. Aivojen tilavuusmittauksissa todettiin aivojen kokonaisvolyymin olevan verrokeita pienempi ja suhteellisen aivoselkäydinnestemäärän olevan tutkittavilla merkittävästi verrokeita suurempi. Verrokeilla neuropsykologinen kokonaissuoriutuminen korreloi positiivisesti harmaan aineen määrään, mutta opioidirippuvaisilla henkilöillä tällaista korrelaatiota ei havaittu, voidaan siis ajatella vieroitusvaiheen muutosten heikentävän opioidiriippuvaisten suoriutumista ehkä pysyvämpiä muutoksia enemmän. Kaikissa eri tutkimuksissa saadut tulokset viittaavat pääosin otsa- ja ohimolohkojen toiminnan ja rakenteen muutoksiin opioidiriippuvaisilla

Multimodal neuroimaging in patients with disorders of consciousness showing "functional hemispherectomy".

Beside behavioral assessment of patients with disorders of consciousness, neuroimaging modalities may offer objective paraclinical markers important for diagnosis and prognosis. They provide information on the structural location and extent of brain lesions (e.g., morphometric MRI and diffusion tensor imaging (DTI-MRI) assessing structural connectivity) but also their functional impact (e.g., metabolic FDG-PET, hemodynamic fMRI, and EEG measurements obtained in "resting state" conditions). We here illustrate the role of multimodal imaging in severe brain injury, presenting a patient in unresponsive wakefulness syndrome (UWS; i.e., vegetative state, VS) and in a "fluctuating" minimally conscious state (MCS). In both cases, resting state FDG-PET, fMRI, and EEG showed a functionally preserved right hemisphere, while DTI showed underlying differences in structural connectivity highlighting the complementarities of these neuroimaging methods in the study of disorders of consciousness.Peer reviewe

Enhancing Nervous System Recovery through Neurobiologics, Neural Interface Training, and Neurorehabilitation.

After an initial period of recovery, human neurological injury has long been thought to be static. In order to improve quality of life for those suffering from stroke, spinal cord injury, or traumatic brain injury, researchers have been working to restore the nervous system and reduce neurological deficits through a number of mechanisms. For example, neurobiologists have been identifying and manipulating components of the intra- and extracellular milieu to alter the regenerative potential of neurons, neuro-engineers have been producing brain-machine and neural interfaces that circumvent lesions to restore functionality, and neurorehabilitation experts have been developing new ways to revitalize the nervous system even in chronic disease. While each of these areas holds promise, their individual paths to clinical relevance remain difficult. Nonetheless, these methods are now able to synergistically enhance recovery of native motor function to levels which were previously believed to be impossible. Furthermore, such recovery can even persist after training, and for the first time there is evidence of functional axonal regrowth and rewiring in the central nervous system of animal models. To attain this type of regeneration, rehabilitation paradigms that pair cortically-based intent with activation of affected circuits and positive neurofeedback appear to be required-a phenomenon which raises new and far reaching questions about the underlying relationship between conscious action and neural repair. For this reason, we argue that multi-modal therapy will be necessary to facilitate a truly robust recovery, and that the success of investigational microscopic techniques may depend on their integration into macroscopic frameworks that include task-based neurorehabilitation. We further identify critical components of future neural repair strategies and explore the most updated knowledge, progress, and challenges in the fields of cellular neuronal repair, neural interfacing, and neurorehabilitation, all with the goal of better understanding neurological injury and how to improve recovery

Aerospace medicine and biology: A continuing bibliography with indexes, supplement 164

This bibliography lists 275 reports, articles, and other documents introduced into the NASA scientific and technical information system in January 1977

Aerospace Medicine and Biology: A continuing bibliography with indexes, supplement 159

This bibliography lists 257 reports, articles, and other documents introduced into the NASA scientific and technical information system in September 1976