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PubMedDate not supplied

Space flight effects on bacterial physiology.

The study of bacterial behavior under space flight conditions is highly important for the early detection of changes in bacterial communities and bacteria with medical, environmental, or life support consequences for survival of the crew in closed space environments. Although many species of prokaryotes have been studied in ground simulation facilities or have been flown in space flights, at present only few hard research data are available to predict the effects of cosmic radiation, microgravity, vibration and hypervelocity on microbial behavior in space flight. The results that are available tend to be fragmentary and often lack a classical, controlled experimental context to interpret them. Thus, many basic questions concerning the effects of space on microbial behavior have yet to be resolved.

Bacteria↗
PubMed2005

An evaluation of survival of space maintainers: a six-year follow-up study.

The aim of this study was to evaluate the median survival time of fixed and removable space maintainers related to age groups, gender, and their distribution in upper and lower dental arches. The adherence of patients to a periodic recall program and the success rate of different types of space maintainers related to different arches were also evaluated. This study included 663 patients aged between 4-15 years old that were treated between the years of 1997 and 2002. The patients were categorized into four main groups: lost to follow-up, failed, successful, and censored at the end of study. Three hundred forty-five space maintainers were considered lost to follow-up, 83 were considered failed, 206 successful, and 20 censored-at-end. The overall median survival time of the appliances was 6.51 months. Median survival time was 7.25 months in the 4-6 age group, 6.35 months in the 7-12 age group, and 7.0 months in the 13+ age groups. Median survival time was 5.76 months in girls and 7.11 months in boys. Median survival time of space maintainers was 7.17 months for maxilla and 6.69 months in the mandible. Median survival time was 5.25 months for space maintainers fabricated in both arches.

Adolescent↗
PubMed2005

[Development of a prototype of space vegetable-cultivating facility for ground-based experiments].

OBJECTIVE: To develop a ground-based experimental prototype of space vegetable-cultivating facility (GEPSVF), so as to solve the main key techniques related to higher plant cultivation in space environmental conditions, and to further lay a foundation for future development and application of the prototype of space vegetable-growing facility. METHOD: Based on detailed demonstration and design of technique plan, the blueprint design and machining of components, whole facility installment, debugging, trial operations and verification experiments were done. RESULT: The parameters in the growing chamber such as temperature, relative humidity, wind velocity, total pressure, O2 partial pressure, CO2 partial pressure and water content of the growing media were totally and effectively controlled; the light source was electronic fluorescent lamp; the average vegetable-producing output reached 60 g (fresh weight) d-1. CONCLUSION: The prototype could operate stably; its actual performance indexes achieved the expected ones basically; some of its operating principles can adapt to space microgravity condition. Therefore, the prototype is a good beginning for future development of space vegetable-producing facilities.

Atmospheric Pressure↗
PubMedDate not supplied

A dual-chambered syringe that allows identification of the epidural space using the loss of resistance technique with air and with saline.

BACKGROUND AND OBJECTIVES: Each of the two most widely used techniques for identification of the epidural space, the loss of resistance technique with air and the loss of resistance technique with liquid, has certain advantages and disadvantages. A new syringe is described that has two chambers, one to contain air and the other to contain liquid, to combine the advantages of air with the advantages of liquid, and to prevent the disadvantages of each. METHODS: Twenty consecutive adult patients scheduled to receive epidural injections for surgery, obstetrics, or pain control were selected for study. This was an open study, and the EpIdent syringe was used as the only means of identifying the epidural space in every case. RESULTS: The EpIdent syringe easily and effectively identified the epidural space in all of the patients, with no adverse or unpleasant side effects. Successful identification of the space was documented by the production of adequate anesthesia after the injection of an appropriate volume or local anesthetic. There were no complications. CONCLUSIONS: The successful use of the EpIdent syringe in this preliminary study of 20 patients indicates that it provides a simple, safe, and effective means of identifying the epidural space. It allows the use of a plastic syringe (instead of glass) and avoids the unpleasant or untoward effects associated with currently used loss of resistance techniques.

Air↗
PubMed2004

Strategies of cell biology experimentation in space.

The purpose of this article is to inform newcomers on the most important aspects of experimentation with living cells and tissues in space laboratories and platforms. There are strong arguments that justify the efforts and investments in such activity. Experimentation in space is subject to safety and technological constraints that require considerable attention to the development of the flight protocols and of the flight instrumentation. Nevertheless to fly an experiment in space is a unique opportunity to study living systems under conditions not reproducible on Earth and it is also a contribution to human exploration of space. Thereby important progress in basic and applied science can be expected. Parallel investigations on ground with devices averaging the exposure to the gravity vector but not reproducing microgravity shall always be part of a space flight project.

Cell Culture Techniques↗
PubMed2005

The subarachnoid space develops early in the human embryonic period.

The anlage of the subarachnoid space is seen in embryos at stage 14 (33 days) in the innermost zone of the primary meninx as irregular spaces on the ventral surface of the spinal cord. At first this space is only on the ventral surface of the spinal cord. From stage 18 (44 days) on, when the dura mater proper is formed, the reticular tissue of the primary meninx and spaces are around the circumference of the spinal cord. These spaces gradually coalesce and contain many blood vessels.

Adult↗
PubMed2006

Fixed space maintainers combined with open-face stainless steel crowns.

OBJECTIVE: This study investigates the clinical performance of fixed space maintainers placed on seriously damaged abutment teeth. METHODS: Crowns were placed on damaged abutment primary teeth. Fixed space maintainers were prepared by using rectangular wire between the window in the facial surface of the crowns and other abutment teeth and were subsequently bonded with a flowable resin composite. This procedure was introduced clinically, and the cases were observed over a period of twelve months. RESULTS: Twenty-seven fixed space maintainers (25 on lower jaw, two on upper jaw) were included in this study. No clinical failure was recorded in any of the cases in the observation time, and the rate of clinical performance was 100%. CONCLUSION: The study shows the effectiveness of fixed space maintainers combined with stainless steel crowns ("open-face fixed space maintainers") which were placed on primary molar teeth used as abutments in cases with extensive caries and loss of occlusogingival dimension.

Child↗
PubMed1989

[Demographic trends: birth spacing].

Two studies to measure children spacing in western metropolitan Santiago are compared. The first (1984-85) surveyed a sample of 687 mothers and the second 1,000. Deliveries took place at San Juan de Dios and Félix Bulnes hospitals (both state-finance) which provide medical care for medium and low income groups. Long spacing (5 years or more) accounted for the highest proportion of non-first born children (33.8% in 1984-85 with a significant increase to 40.1% in 1988) while short spacing (under 2 years) accounted for 19.2% in 1984-85 and 21.8% in 1988 (not significant). Mean birth weights were over 3,200 g in every spacing group. Despite the low illiteracy rate, predominant urban origin and having at least one child born before, high proportions of children were conceived despite the use of contraceptive measures (19.7% in 1984-85 and 22.5% in 1988). This contraceptive failure was less frequent among children born after longer spacings.

Birth Intervals↗
PubMedDate not supplied

[Computed tomographic anatomy of the kidneys and the retroperitoneal space].

The authors described the anatomy of the kidneys and retroperitoneal space in health on the basis of CT of 90 patients. Five typical levels in CT (ensuring all necessary data on roentgenomorphological traits of the kidneys and retroperitoneal space in the kidney area) were singled out. Some roentgenometric data on kidney cross-sections as well as the quantitative densitometric characterization of the parenchyma of the kidneys, renal sinus and adjacent tissues were presented. X-ray anatomy of the renal fascia, pararenal space and perirenal fatty space of the kidney with different parts of the retroperitoneal space was described.

Adult↗
PubMed1986

Influence of space flight on red blood cells.

Losses of red blood cell mass (RCM) averaging 10-15% have been observed consistently in astronauts after space flight; postflight recovery of RCM requires 4-6 wk. Although apparently not harmful to the health and effectiveness of crews during uncomplicated flights, decreased RCM could compromise health and performance in the event of illness, injury, or partial malfunction of the life support system. Whether the loss of RCM would worsen or stabilize in missions longer than 7 months is unknown. As a biological response, it is a significant, predictable reaction whose etiology, biological mechanisms, and potential operational significance are inadequately defined. Weightlessness is probably the primary cause; however, contributory factors may include hypokinesia/hypodynamia, bone loss, muscle atrophy, altered hemodynamics, stress, and metabolic disturbances. Space medical specialists consider other possible influences such as hypoxia, hypobaria, radiation, toxic contaminants, and launch and reentry accelerations as less likely factors. Because the data base on loss of RCM is insufficient for the National Aeronautics and Space Administration's space medical responsibilities, the Life Sciences Research Office ad hoc Working Group on Space Anemia suggested research approaches ranging form fundamental topics such as utilization of erythropoietin and oxygen in target organs and cell-cell interactions, through possible splenic and vascular dysfunctions, metabolic disturbances, and inhibitors of erythropoiesis, to methodology and models.

Body Weight↗
PubMed1987

The biological clock of Chlamydomonas reinhardii in space.

The overt circadian rhythm in a wildtype (wt+) and a short period (s-) strain of Chlamydomonas reinhardii has been studied in space using the photoaccumulation behavior as the recorded parameter. The period of the wt+ was 29.6 h, of the s- 21.4 h and did not deviate significantly from ground controls performed exactly at the same time. The phase was delayed in space by 4.2 h in the wt+, but was not altered in the s-. In both strains the amplitudes were significantly higher in space than in the ground controls. During the recording period of 6.5 days the cell density increased in both strains. The survival rate, i.e. the ability to form colonies on agar petri dishes, was higher in space than on ground. The period was in both strains by 1.1 h longer in Florida (Kennedy Space Center) in both the flight and the control samples than in Europe. The significance of these results is discussed with respect to the endogenous nature of the biological clock and the role of the microgravity environment.

Cell Division↗
PubMedDate not supplied

[Pathology of perivascular spaces in the central nervous system].

The perivascular spaces of the central nervous system are involved in various pathological situations. The aim of this paper is to focus on the histopathological lesions of the perivascular spaces which commonly occur in the infectious (bacterial, viral, parasitic), tumoral (carcinoma, lymphoma, leukemia), demyelinating (multiple sclerosis, allergic encephalomyelitis) and vascular diseases of the brain. According to their apparent function in each of these situations an attempt was made to classify the main physiopathological processes involving the perivascular spaces into 3 distinct groups. The perivascular spaces may be considered as follows: (1) double way route between the parenchyma and the leptomeningeal space (extension to the brain of a meningeal pathological process, drainage of parenchymal wastes); (2) elective location of the inflammatory reaction partly as a result of the presence of connective tissue; (3) site of particular lesions such as dilatation, the pathogenesis of which remains unclear.

Brain↗
PubMed1980

Albumin shifts across the extracellular space secondary to experimental infections.

The pathway across tissue spaces of intravenously injected 125I albumin was studied in five dogs before and after the injection of Escherichia coli endotoxin by the use of perforated plastic capsules placed in the subcutaneous tissue. The already negative extracellular space pressure became less so after the endotoxin injection, when albumin was detected shifting from the intravascular space into the extracellular space compartment and then into the intralymphatic space. The injection of endotoxin produced a marked increase in the thoracic duct lymph flow, while, at the same time, erythrocytes entered the lymphatic stream. Results of this study suggest that experimental canine endotoxemia is associated with an increased passage of albumin into the extravascular compartment and explains, in part, the fall in serum levels of this protein during clinical and experimental sepsis.

Animals↗
PubMed1982

[Results of endocrinologic studies of the 3d international crew of the scientific orbital station complex: Soyuz 29 - Salyut 6 - Soyuz 31 (joint space flight enterprise of the USSR - GDR). 3. Corticosteroid excretion in urine].

In the present study the attempt was made to evaluate the functional state of the adrenal cortex after space flight by means of the urinary corticosteroid content. The urine collected over 24 hours was analysed. The following parameters were determined: Total 17-hydroxycorticosteroids (17-OHCS), their free forms, glucuronides and sulphates; cortisol (F), cortisone (E), corticosterone (B), 11-desoxycortisol (S), 11-dehydrocorticosterone (A), tetrahydrocortisol (THF), tetrahydrocortisone (THE), tetrahydrocorticosterone (THB), tetrahydro-11-desoxycortisol (THS), and aldosterone. In order to characterize the activity of the 11-hydroxylase the quotient of THS + S/THF + F + THE + E was formed. The activity of the 17-hydroxylase was determined indirectly by the quotient of THF + THE + THS + F + E + S/THB + B + A = 17-OHCS/17-DOHCS. The expected distinct increase of the 17-OHCS after the space flight failed to appear. This finding may be due to an adrenocortical dysfunction. In the space ship commander the quotients indicate a reduced 11- and 17-hydroxylation during the process of synthesis of the glucocorticoids. In the flight engineer they give evidence of an unchanged biosynthesis except on the day of landing. A hitherto not fully intensified substance ("white spot") was found in the chromatogram of the space ship commander on the first and second day after the flight. Moreover, the investigations show that the reaction of the adrenal cortex after space flights exhibits a number of individual characteristics.

Adrenal Cortex Hormones↗
PubMed1994

[The world as inner space. Kafka's "The Burrow" as a paradigm of paranoid spatial experience].

The paranoid's experience of space is illustrated in the present study by means of an investigation of paraphrenic senile psychosis and an analysis of Kafka's short story, "The Burrow". This may be characterized as an experience of increasing permeability and disintegration of boundaries between one's own, private space and that belonging to others, or between inside and outside. At first, a latent ego-weakness is compensated by shifting the self-boundaries onto the territory of one's dwelling which serves as an "external shell" for the self. The emphasis on fencing-off and isolation from the external world, however, renders the hidden, inner spaces ever more threatening. The protecting barriers change into fragile facades through which enemies are able to attack. Finally, the sheltering but, nevertheless, exposed inner spaces fall prey to threats from the outside. Paradoxically, the disintegration of the inner space of self comes about by the paranoid constantly taking the view point of his fictitious enemies; he, thereby, sees through and penetrates the very barriers which he himself has erected.

Aged↗
PubMed1994

Physical performance is maintained in women consuming only foods used on the U.S. Space Shuttle.

In-flight reductions in caloric intake, body weight, lean body mass (LBM), aerobic capacity, and other measures of physical performance have been consistent findings in the U.S. and Russian space programs. The diet provided for astronauts in space has been suggested as a possible contributor to these changes because food selection, preparation, and storage facilities are limited on spacecraft. In this ground-based study, consuming only foods used on the Space Shuttle for 28 d did not affect aerobic capacity, LBM, or measures of muscle strength or endurance in 12 healthy women (ages 28-47 years). However, normal consumption patterns were affected by restriction to the Space Shuttle diet, namely a proportional increase in carbohydrate consumed, with compensatory decreases in protein and fat. These results suggest that physical performance and LBM can be maintained under normal gravity conditions in active women who consume a Space Shuttle food-system diet for 28 d.

Adult↗
PubMedDate not supplied

[A topographic anatomical basis to approaches for instrumental interventions in diseases of the organs of the retroperitoneal space].

Retroperitoneoscope was introduced through the 11 and 10 intercostal space by linea axillaris media and anterior Differences of the accesses between each other and between those in lumbocostal angle are statistically significant. The access to 11 intercostal space was proved to be the most convenient one for the examination of the entire kidney surface, while the one to 10 intercostal space-for the endoscopy of adrenals and caudal region of the pancreas. The caput of the pancreas may be examined both through 11 intercostal space and lumbocostal angle. Clinical observations of 129 patients, operated by means of retroperitoneoscope through 11 intercostal space confirmed the effectivity of the method. Positive effects of retroperitoneoscopy_-minimal traumatization of tissues, normal postoperative period and good cosmetic effect make it suitable for wide introduction into the surgical practice.

Adolescent↗
PubMed1996

[A fluoroscopic analysis of the catheters abnormally placed in the epidural space].

In order to know how the catheters are placed abnormally in the epidural space, we inserted the epidural catheters under fluoroscopy. The catheter was placed straightly upward when the epidural puncture was done in the center of epidural space. When the puncture site was nearly close to the side wall of epidural space, we could not insert catheter at all. When the tip of the needle was near the side wall and the inserting catheter slipped upward, catheter was placed straight. When the catheter wedged at the side wall, it made loop and curled or kinked. We thought that the cause of abnormal location of the catheters in epidural space is the right angle between the wall of the epidural space and the direction of catheter.

Adult↗