The hypothesis tested by this project is that space flight increases the incidence and duration of herpes virus reactivation and shedding in saliva. Saliva, urine, and blood samples were collected ...from 3 crew members who participated in a 14-day Odessa Soyuz taxi mission. Saliva samples were collected before, during, and after the mission, and blood and urine were collected before and after the mission. The saliva and urine samples were analyzed using the polymerase chain reaction to detect the presence of 3 important herpes viruses. Epstein-Barr virus (EBV) and varicella-zoster virus (VZV) were tested in saliva, and cytomegalovirus (CMV) was measured in urine samples. Plasma antibodies levels to these viruses were determined by enzyme-linked immunosorbent assay before and after flight. EBV reactivated before, during, and after flight; CMV reactivated before and after flight; and VZV reactivated during and after flight. In other studies, greater frequencies of positive samples and greater numbers of copies of viral DNA have been found. No increases in titer of antibodies to these viruses were found, suggesting that an immune response may not be necessary for reactivation.
Cytotoxic activity of non-major histocompatibility complex-restricted (CD56+) (NMHC) killer cells and cell surface marker expression of peripheral blood mononuclear cells were determined before and ...after spaceflight. Ten astronauts (9 men, 1 woman) from two space shuttle missions (9- and 10-day duration) participated in the study. Blood samples were collected 10 days before launch, within 3 h after landing, and 3 days after landing. All peripheral blood mononuclear cell preparations were cryopreserved and analyzed simultaneously in a 4-h cytotoxicity (51)Cr release assay using K562 target cells. NMHC killer cell lytic activity was normalized per 1,000 CD56+ cells. When all 10 subjects were considered as one study group, NMHC killer cell numbers did not change significantly during the three sampling periods, but at landing lytic activity had decreased by approximately 40% (P < 0.05) from preflight values. Nine of ten astronauts had decreased lytic activity immediately after flight. NMHC killer cell cytotoxicity of only three astronauts returned toward preflight values by 3 days after landing. Consistent with decreased NMHC killer cell cytotoxicity, urinary cortisol significantly increased after landing compared with preflight levels. Plasma cortisol and ACTH levels at landing were not significantly different from preflight values. No correlation of changes in NMHC killer cell function or hormone levels with factors such as age, gender, mission, or spaceflight experience was found. After landing, expression of the major lymphocyte surface markers (CD3, CD4, CD8, CD14, CD16, CD56), as determined by flow cytometric analysis, did not show any consistent changes from measurements made before flight.
More effective antibiotics are needed to overcome the problem of multidrug resistance. The antibacterial efficacies of three Zn-based nano metal-organic frameworks (nMOFs) - IRMOF-3, MOF-5, and ...Zn-BTC - were explored, both alone and as mixtures with ampicillin and kanamycin. When tested against
Escherichia coli
,
Staphylococcus aureus
,
Staphylococcus lentus
, and
Listeria monocytogenes
, the nMOF/drug mixtures demonstrated synergistic (IRMOF-3/kanamycin) or additive (other nMOF/drug combinations) effects compared with the nMOFs or antibiotics alone. Zn-Based nMOFs can reduce the burden of the new discovery of antimicrobial pharmaceuticals by increasing the potency of existing antibiotics.
More effective antibiotics are needed to overcome the problem of multidrug resistance.
More effective antibiotics are needed to overcome the problem of multidrug resistance.
More effective antibiotics are needed to overcome the problem of multidrug resistance. The antibacterial ...efficacies of three Zn-based nano metal–organic frameworks (nMOFs) – IRMOF-3, MOF-5, and Zn-BTC – were explored, both alone and as mixtures with ampicillin and kanamycin. When tested against
Escherichia coli
,
Staphylococcus aureus
,
Staphylococcus lentus
, and
Listeria monocytogenes
, the nMOF/drug mixtures demonstrated synergistic (IRMOF-3/kanamycin) or additive (other nMOF/drug combinations) effects compared with the nMOFs or antibiotics alone. Zn-Based nMOFs can reduce the burden of the new discovery of antimicrobial pharmaceuticals by increasing the potency of existing antibiotics.
Numerous studies have indicated that dysregulation of the immune system occurs during or after spaceflight. Using 21 day 6 head-down tilt bed rest as a spaceflight analog, this study describes the ...effects of a daily artificial gravity (AG) countermeasure treatment on immunity, stress, and reactivation of clinically important latent herpes viruses. Blood, saliva, and urine samples were collected from each of the 15 male test subjects (8 treatment, 7 control) periodically throughout the study. The immune assessment consisted of a comprehensive peripheral immunophenotype analysis, intracellular cytokine profiles, and measurement of T cell function. With the exception of mild reactivation of Epstein-Barr (EBV) and Varicella zoster (VZV) viruses, no significant changes in immune function were observed, suggesting that the AG countermeasure and the 21 day head-down tilt bed rest regimen had no adverse effect on immune function.
Airborne fungi were monitored at five sample sites with the Burkard portable, the RCS Plus, and the SAS Super 90 air samplers; the Andersen 2-stage impactor was used for comparison. All samplers were ...calibrated before being used simultaneously to collect 100-liter samples at each site. The Andersen and Burkard samplers retrieved equivalent volumes of airborne fungi; the SAS Super 90 and RCS Plus measurements did not differ from each other but were significantly lower than those obtained with the Andersen or Burkard samplers. Total fungal counts correlated linearly with Cladosporium and Penicillium counts. Alternaria species, although present at all sites, did not correlate with total count or with amounts of any other fungal genera. Sampler and location significantly influenced fungal counts, but no interactions between samplers and locations were found
Thirty-three families (71 subjects) were screened for the presence of
Candida albicans in mouthwash or stool specimens; 12 families (28 subjects) were culture-positive for this yeast. An enrichment ...procedure provided a twofold increase in the recovery of
C. albicans from mouthwash specimens. Nine of the twelve culture-positive families had two positive members each, two families had three positive members each, and one family had four positive members. Genetic profiles were obtained by three methods: pulsed-field gel electrophoresis; restriction endonuclease analysis, and random amplification of polymorphic DNA analysis. DNA fingerprinting of
C. albicans isolated from one body site three consecutive times revealed that each of the 12 families carried a distinct genotype. No two families shared the same strain, and two or more members of a family commonly shared the same strain. Intrafamily genotypic identity (i.e., each member within the family harbored the same strain) was demonstrated in six families. Genotypes of isolates from husband and wife differed from one another in five families. All three methods were satisfactory in determining genotypes; however, we concluded that restriction endonuclease analysis provided adequate resolving power.
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