Intermittent neck flexion induces greater sternocleidomastoid deoxygenation than inspiratory threshold loading.

PURPOSE: To compare deoxygenation of the sternocleidomastoid, scalenes, and diaphragm/intercostals (Dia/IC) during submaximal intermittent neck flexion (INF) versus submaximal inspiratory threshold loading (ITL) in healthy adults. METHODS: Fourteen participants performed a randomized, cross-over, repeated measures design. After evaluation of maximal inspiratory pressures (MIP) and maximum voluntary contraction (MVC) for isometric neck flexion, participants were randomly assigned to submaximal ITL or INF until task failure. At least 2 days later, they performed the submaximal exercises in the opposite order. ITL or INF targeted 50 ± 5% of the MIP or MVC, respectively, until task failure. Near-infrared spectroscopy (NIRS) was applied to evaluate changes of deoxy-hemoglobin (ΔHHb), oxy-hemoglobin (ΔO2Hb), total hemoglobin (ΔtHb), and tissue saturation of oxygen (StO2) of the sternocleidomastoid, scalenes, and Dia/IC. Breathlessness and perceived exertion were evaluated using Borg scales. RESULTS: Initially during INF, sternocleidomastoid HHb slope was greatest compared to the scalenes and Dia/IC. At isotime (6.5-7 min), ΔtHb (a marker of blood volume) and ΔO2Hb of the sternocleidomastoid were higher during INF than ITL. Sternocleidomastoid HHb, O2Hb, and tHb during INF also increased at quartile and task failure timepoints. In contrast, scalene ΔO2Hb was higher during ITL than INF at isotime. Further, Dia/IC O2Hb and tHb increased during ITL at the third quartile and at task failure. Borg scores were lower at task failure during INF compared to ITL. CONCLUSION: Intermittent INF induces significant metabolic activity of the sternocleidomastoid and a lower perception of effort, which may provide an alternative inspiratory muscle training approach for mechanically ventilated patients.

Muscle and cerebral oxygenation during cycling in chronic obstructive pulmonary disease: A scoping review.

To synthesize evidence for prefrontal cortex (PFC), quadriceps, and respiratory muscle oxygenation using near-infrared spectroscopy (NIRS) during cycling in individuals with chronic obstructive pulmonary disease (COPD). A scoping review was performed searching databases (inception-August 2020): Ovid MEDLINE, EMBASE, Cochrane Systematic Reviews, Cochrane Central Register of Controlled Clinical Trials, CINAHL, SPORTDiscus and Pedro. The search focused on COPD, cycling, and NIRS outcomes. 29 studies (541 COPD participants) were included. Compared to healthy individuals (8 studies), COPD patients at lower cycling workloads had more rapid increases in vastus lateralis (VL) deoxygenated hemoglobin (HHb); lower increases in VL total hemoglobin (tHb) and blood flow; and lower muscle tissue saturation (StO2). Heliox and bronchodilators were associated with smaller and slower increases in VL HHb. Heliox increased VL and intercostal blood flow compared to room air and supplemental oxygen in COPD patients (1 study). PFC oxygenated hemoglobin (O2Hb) increased in COPD individuals during cycling in 5 of 8 studies. Individuals with COPD and heart failure demonstrated worse VL and PFC NIRS outcomes compared to patients with only COPD-higher or more rapid increase in VL HHb and no change or decrease in PFC O2Hb. Individuals with COPD present with a mismatch between muscle oxygen delivery and utilization, characterized by more rapid increase in VL HHb, lower muscle O2Hb and lower muscle StO2. PFC O2Hb increases or tends to increase in individuals with COPD during exercise, but this relationship warrants further investigation. NIRS can be used to identify key deoxygenation thresholds during exercise to inform PFC and muscle oxygenation.

Evaluating driver eye glance behavior and secondary task engagement while using driving automation systems.

Partial driving automation systems are designed to assist drivers in some vehicle operation demands. However, modifications to the driving task that change the driver's role from that of an active participant to a passive supervisor could result in insufficient monitoring of the driving automation system and the surrounding environment. A reduced subset of driving data for 19 drivers from the Virginia Connected Corridors 50 Elite Naturalistic Driving Study was used to assess whether driver eye glance behavior and secondary task engagement were different when driver assistance systems were active compared to when they were available but inactive (n = 148). The results of this study demonstrate that drivers spent more time looking away from the road while driving automation systems were active and that drivers were more likely to be observed browsing on their cell phones while using driving automation systems. Current driving automation features require human monitoring of automation, yet the drivers of these automation-equipped vehicles are inclined to engage in secondary tasks and take longer and more frequent glances away from the roadway. It is possible that performance effects, such as omission errors or delayed reactions, may occur as a result of drivers' substandard monitoring of the driving scene.

Molecular and functional characterization of a novel splice variant of ANKHD1 that lacks the KH domain and its role in cell survival and apoptosis.

Multiple ankyrin repeat motif-containing proteins play an important role in protein-protein interactions. ANKHD1 proteins are known to possess multiple ankyrin repeat domains and a single KH domain with no known function. Using yeast two-hybrid system analysis, we identified a novel splice variant of ANKHD1. This splice variant of ANKHD1, which we designated as HIV-1 Vpr-binding ankyrin repeat protein (VBARP), does not contain the signature KH domain, and codes for only a single ankyrin repeat motif. We characterized VBARP by molecular and functional analysis, revealing that VBARP is ubiquitously expressed in different tissues as well as cell lines of different lineage. In addition, blast searches indicated that orthologs and homologs to VBARP exist in different phyla, suggesting that VBARP might be evolutionarily conserved, and thus may be involved in basic cellular function(s). Furthermore, biochemical analysis revealed the presence of two VBARP isoforms coding for 69 and 49 kDa polypeptides, respectively, that are primarily localized in the cytoplasm. Functional analysis using short interfering RNA approaches indicate that this gene product is essential for cell survival through its regulation of caspases. Taken together, these results indicate that VBARP is a novel splice variant of ANKHD1 and may play a role in cellular apoptosis (antiapoptotic) and cell survival pathway(s).

Reliability of the long-range power-law correlations obtained from the bilateral stride intervals in asymptomatic volunteers whilst treadmill walking.

Stride intervals measured during steady-state walking are irregular. These stride interval fluctuations are not random but exhibit long-range power-law correlation (alpha) such that a given stride interval is 'influenced' by earlier variations in the stride intervals. To estimate alpha, one requires a minute long sequence of right or left side stride interval data. However, to obtain a reliable alpha point estimate, the minimal stride sequence length is unknown. Additionally, it is unknown if the right and left side alpha are equivalent. In this study, the within-day and the right and left side reliabilities of alpha point estimates were examined in 23 volunteers performing three 8-min treadmill walks. In addition, eight volunteers were retested on three additional days to estimate between-day reliability. The standard error of measurement (S.E.M.) and the within- and between-day intraclass correlation (ICC) values, and their 95% confidence intervals, each calculated using the combined right and left leg 8-min alpha estimates were acceptable [0.047 (0.044-0.051); 0.914 (0.882-0.932) and 0.769 (0.689-0.815), respectively]. The left alpha (0.688 +/- 0.93) was greater than the right alpha (0.664 +/- 0.094), albeit this finding was underpowered (0.55). The alpha point estimates obtained from the full 8-min walks provided minimal S.E.M. and maximal within- and between-day ICCs. However, the minimal S.E.M. was statistically indistinguishable from the 6- and 7-min walk durations and all of the within-day and between-day ICCs were similar except for the 3- and 8-min between-day ICCs. This study suggests that data from four 3 min, three 6 min or two 8 min walk duration trials provide reliable alpha point estimates from a short series of short treadmill walks.

Occupational injury and illness among migrant and seasonal farmworkers in New York State and Pennsylvania, 1997-1999: pilot study of a new surveillance method.

BACKGROUND: Traditional worksite injury surveillance methods are often ineffective for Northeastern farms employing seasonal harvest labor. Many are small farms, exempt from mandatory injury reporting. The high proportion of foreign workers and the temporary nature of the work further discourages reporting. Therefore, an alternative migrant health center-based occupational injury and illness surveillance system was piloted during 1997-1999. METHODS: Anonymous medical chart data from nine migrant health centers and four regional hospital emergency rooms was collected during 1997-1999. RESULTS: There were 516 injury/illness cases over two seasons. Joint/muscle straining (31%), falling (18%), poison ivy contact (10%), and object strikes (8%) were most common injurious events. The participation rate of health care was 75%; 130 cases were reported by hospital emergency rooms; and optimal health center participation was associated with: being a farmworker-dedicated program, and including the chart reviewer in the health center's decision to participate. CONCLUSIONS: Further development of a medical records-based surveillance system should include hospital emergency rooms and focus on identified health center performance factors.

Reclamation of pesticides in New York State.

BACKGROUND: Unwanted agrichemicals pose a unique threat that many states now address this with statewide collection programs. In New York, this is done at the discretion of individual counties. METHODS: We compiled and analyzed registration inventories from five separate county-based pesticide collections located in three different agricultural regions. Telephone surveys of thirty-one of New York's leading agricultural counties gathered information on their strategies for disposal of unwanted pesticides. RESULTS: The combined collections yielded 54,214 pounds of pesticides from 123 farms (441 lbs/farm). The most common active ingredients collected included older (and often discontinued) agents such as organochlorine (5,355 lbs, 9.8%) and arsenic (3,832 lbs, 7.1%) compounds, as well as more modern and commonly used active ingredients such as organophosphate pesticides (3,200 lbs, 5.9%). Disposal costs ranged from $2.03 to $2.86 per pound. Data from three collections indicated that 27% of the recovered pesticide (13,123 lbs) was stored in "unacceptable", "leaky", or "poor" containers. Of 31 agricultural counties, only 17 (55%) have hosted at least one farm pesticide collection event in the past. Planning for future collections is quite limited. CONCLUSIONS: There is a potentially large amount of toxic chemicals, some in decaying containers, that poses a risk to soil and groundwater in the state. The planning of future collections in New York State is haphazard. Carefully designed pesticide collection projects can be effective and should be a priority for local and state health officials.