Participants in the Trans-Antarctic Winter Traverse Expedition Showed Increased Bacterial Load and Diversity in Saliva but Maintained Individual Differences within Stool Microbiota and Across Metabolite Fingerprints.

Understanding the impact of long-term physiological and environmental stress on the human microbiota and metabolome may be important for the success of space flight. This work is logistically difficult and has a limited number of available participants. Terrestrial analogies present important opportunities to understand changes in the microbiota and metabolome and how this may impact participant health and fitness. Here, we present work from one such analogy: the Transarctic Winter Traverse expedition, which we believe is the first assessment of the microbiota and metabolome from different bodily locations during prolonged environmental and physiological stress. Bacterial load and diversity were significantly higher during the expedition when compared with baseline levels (p < 0.001) in saliva but not stool, and only a single operational taxonomic unit assigned to the Ruminococcaceae family shows significantly altered levels in stool (p < 0.001). Metabolite fingerprints show the maintenance of individual differences across saliva, stool, and plasma samples when analysed using flow infusion electrospray mass spectrometry and Fourier transform infrared spectroscopy. Significant activity-associated changes in terms of both bacterial diversity and load are seen in saliva but not in stool, and participant differences in metabolite fingerprints persist across all three sample types.

Incidence and risk factors associated with venous thromboembolism following primary total hip arthroplasty in low-risk patients when using aspirin for prophylaxis.

AIMS: The primary aim was to assess the incidence of venous thromboembolism (VTE) following total hip replacements (THR) in a low-risk patient group when using 150 mg aspirin as the pharmacological component of VTE prophylaxis on discharge. The secondary aim was to identify factors associated with an increased risk of a VTE event in this low-risk group. PATIENTS AND METHODS: Retrospective review of a consecutive cohort of patients undergoing THR during a 63-month period. Patient demographics, socio-economic status, ASA grade, type of anaesthetic, length of surgery and BMI were recorded. A diagnosis of VTE was assigned to symptomatic patients with positive imaging for a deep vein thrombosis (DVT) and/or a pulmonary embolism (PE) within 8 weeks of surgery. Multivariate logistic regression modeling was used to identify factors associated with VTE after THR. RESULTS: 3880 patients underwent THR during the study period, of which 2740 (71%) were low risk and prescribed aspirin for VTE prophylaxis. There were 34 VTE events, of which 15 were DVTs and 18 were PEs, with 1 patient diagnosed with both. The incidence of VTE was 1.2%, with no VTE-related deaths. Patients incurring a VTE postoperatively were more likely to be male (odds ratio [OR] 2.06, p = 0.022), of older age (OR 0.43, p = 0.047) and were more likely to be socially deprived (OR 0.32, p = 0.006). There was no significant difference with patients given low-molecular-weight heparin (LMWH) as an inpatient prior to discharge on aspirin (p = 0.806), nor any difference with the type of anaesthetic used during surgery (p = 0.719). CONCLUSIONS: Aspirin is a relatively safe and effective choice for VTE prophylaxis in low-risk patients undergoing THR. Male sex and age >70 years were twice as likely to sustain a VTE and patients from the most deprived socio-economic background are 3 times as likely.

The Effect of Ring Finger Distal Interphalangeal Joint Stiffness on Grip Strength: A Simulated Study in Normal Participants.

Background: Pain of the hand distal interphalangeal joints may result from trauma, osteoarthritis or inflammatory arthritis. When symptoms are not controlled by non-operative means, surgical arthrodesis may be performed, resulting in complete stiffness of the joint and possible weakening of grip strength. This study aims to quantify the effect of a stiff ring finger distal interphalangeal joint on overall grip strength. Methods: One hundred participants were screened to exclude upper limb pathology. A Jamar dynamometer was used to assess overall hand grip strength. A splint was used to prevent distal interphalangeal joint flexion, thus replicating a fused distal interphalangeal joint. Participants were tested with and without the splint and the results compared. The mean of three grip strength tests was taken. Results: The participants included 55 females. Mean age was 31 (18-60 years). 76 participants had a reduction in grip strength with splinting, with a significant difference seen (p < 0.05) on Wilcoxon signed rank test. The median reduction in grip strength with splinting was 1.67 kg. However only 10 participants (10%) had a grip strength loss of greater than 6.5 kg, which is the minimal clinically important difference. Conclusions: This study found a significant loss in overall hand grip strength when the ring finger distal interphalangeal joint was stiffened. However, despite this significant change, only 10 (10%) participants experienced a reduction of greater than 6.5 kg. This is the level of weakness felt to be required to reduce function. Thus our results suggest that 90% of patients with a stiff ring finger distal interphalangeal joint are unlikely to have a clinically identifiable functional reduction in grip strength as a result.

Comparison of Aspergillus ear rot and aflatoxin contamination in grain of high-oil and normal-oil corn hybrids.

High-oil corn (Zea mays L.) grain is a valuable component of feed for monogastric livestock. One method of increasing the concentration of oil in corn grain is the TopCross method. With TopCross, ears of a cytoplasmic male-sterile, normal-oil hybrid are pollinated by a male-fertile, high-oil synthetic hybrid. The concentration of oil in the resulting grain is increased because of xenia effects. Kernels of high-oil corn typically have a larger germ and a smaller endosperm than kernels of comparable normal hybrids. The growth of Aspergillus flavus Link:Fr within germ tissue has been reported to be more extensive than that on the whole corn kernel; therefore, the severity of Aspergillus ear rot could be more extensive and aflatoxin concentrations could be higher in high-oil grain produced by TopCross than in grain with a lower concentration of oil. The objective of this study was to compare Aspergillus ear rot severity levels and aflatoxin concentrations in the grains of hybrids crossed with high-oil or normal-oil pollinators. Fifteen hybrids were evaluated in 1998 and 1999 in Urbana, Ill. Primary ears were inoculated with A. flavus and evaluated for susceptibility to Aspergillus ear rot and aflatoxin production in grain. Concentrations of aflatoxin and oil in corn kernels were significantly higher for high-oil hybrids than for normal-oil hybrids; however, ear rot severity was unaffected by the type of pollinator. These results suggest that grain from high-oil hybrids is at greater risk for aflatoxin contamination during some growing seasons.

Enhancement of vitamin E levels in corn.

Vitamin E is the common name that describes eight naturally occurring compounds possessing alpha-tocopherol activity. These eight vitamin E compounds are collectively termed tocols, and all have antioxidant activity. There is natural variation among different corn breeding lines for levels of tocols. The two predominant isomers present in corn grain are gamma-tocopherol and alpha-tocopherol. Alpha-tocopherol is considered more desirable for human and animal consumption because it has higher biological activity than gamma-tocopherol. Most corn breeding lines naturally have much more gamma-tocopherol than alpha-tocopherol. Therefore a breeding goal is to increase levels of alpha-tocopherol relative to gamma-tocopherol. However, recent research suggests that gamma-tocopherol and compounds metabolized from it have properties important to human health that are unique from properties of alpha-tocopherol. Therefore it may be desirable to not only increase levels of alpha-tocopherol in corn grain, but also levels of gamma-tocopherol. Determination of levels of tocopherols in corn grain is very laborious, requires HPLC analysis and is too time consuming for use in routine commercial corn breeding programs. Therefore we are performing biotechnology enabled molecular marker mapping of chromosomal regions with genes that control levels and ratios of alpha- and gamma-tocopherol. Breeders can use molecular markers we have identified to expediently select for desirable alleles of genes that will improve levels of alpha- and gamma-tocopherol in corn grain, without having to perform laborious HPLC assays. Another biotechnology strategy we have initiated is genetic transformation of corn with the gamma-tocopherol methyl transferase gene to enhance conversion of gamma-tocopherol to alpha-tocopherol and thus increase levels of alpha-tocopherol. This transgenic strategy has been demonstrated in the model plant Arabidopsis, and we are now applying this approach to corn.