Assessment of a Fruit and Vegetable Prescription Program in the Northern Manhattan Community.

PURPOSE: This study aimed to assess whether produce prescription redemption was associated with food insecurity (FI), sociodemographics, and nutrition-related health measures, and to identify factors affecting participation. DESIGN: Retrospective, cross-sectional study. Patients, equally divided between groups who redeemed and did not redeem prescriptions, completed a follow-up survey. SETTING: Northern Manhattan, NY. SUBJECTS: 242 patients referred to Nutrition at an academic medical center between June and November 2019. INTERVENTION: All patients referred to Nutrition received prescriptions for produce at local Greenmarkets (patients with FI received $20; other patients received $10). MEASURES: We assessed patient satisfaction and factors impacting participation. Sociodemographics and nutrition-related health measures were extracted from medical records. ANALYSIS: The χ2 test for categorical data and Student's t-test for continuous variables. RESULTS: Prescription redeemers were significantly more likely to be very satisfied with the program (P < .001), have FI (P < .01), and have elevated hemoglobin A1C than non-redeemers (6.3 vs 5.5%, P < .001). Distance, time constraints, and forgetting or losing the prescription were common barriers, while convenience and valuing healthy eating facilitated redemption. CONCLUSION: Higher FI and worse hemoglobin A1c in patients who redeemed prescriptions suggests that our program reaches the target audience: patients needing food assistance and a healthier diet. Awareness of barriers offers areas for improvement. This provides a feasible model for hospital investment to increase access to produce to improve health and health equity.

Antiapoptotic properties of α-crystallin-derived peptide chaperones and characterization of their uptake transporters in human RPE cells.

PURPOSE: The chaperone proteins, α-crystallins, also possess antiapoptotic properties. The purpose of the present study was to investigate whether 19 to 20-mer α-crystallin-derived mini-chaperone peptides (α-crystallin mini-chaperone) are antiapoptotic, and to identify their putative transporters in human fetal RPE (hfRPE) cells. METHODS: Cell death and caspase-3 activation induced by oxidative stress were quantified in early passage hfRPE cells in the presence of 19 to 20-mer αA- or αB-crystallin-derived or scrambled peptides. Cellular uptake of fluorescein-labeled, α-crystallin-derived mini-peptides and recombinant full-length αB-crystallin was determined in confluent hfRPE. The entry mechanism in hfRPE cells for α-crystallin mini-peptides was investigated. The protective role of polycaprolactone (PCL) nanoparticle encapsulated αB-crystallin mini-chaperone peptides from H2O2-induced cell death was studied. RESULTS: Primary hfRPE cells exposed to oxidative stress and either αA- or αB-crystallin mini-chaperones remained viable and showed marked inhibition of both cell death and activation of caspase-3. Uptake of full-length αB-crystallin was minimal while a time-dependent uptake of αB-crystallin-derived peptide was observed. The mini-peptides entered the hfRPE cells via the sodium-coupled oligopeptide transporters 1 and 2 (SOPT1, SOPT2). PCL nanoparticles containing αB-crystallin mini-chaperone were also taken up and protected hfRPE from H2O2-induced cell death at significantly lower concentrations than free αB-crystallin mini-chaperone peptide. CONCLUSIONS: αA- and αB-crystallin mini-chaperones offer protection to hfRPE cells and inhibit caspase-3 activation. The oligopeptide transporters SOPT1 and SOPT2 mediate the uptake of these peptides in RPE cells. Nanodelivery of αB-crystallin-derived mini-chaperone peptide offers an alternative approach for protection of hfRPE cells from oxidant injury.

Decompression sickness risk model: development and validation by 150 prospective hypobaric exposures.

INTRODUCTION: High altitude exposure has an inherent risk of altitude decompression sickness (DCS). A predictive DCS model was needed to reduce operational risk. To be operationally acceptable, such a theoretical model would need to be validated in the laboratory using human subjects. METHODS: The Air Force Research Laboratory (AFRL) has conducted numerous studies on human subjects exposed to simulated altitudes in hypobaric chambers. The database from those studies was used to develop a statistical altitude DCS model. In addition, a bubble growth model was developed using a finite difference method to solve for bubble radius as a function of time. The bubble growth model, integrated with the statistical model, constitutes the AFRL DCS Risk Assessment Model. Validation of the model was accomplished by comparing computer predictions of DCS risk with results from subsequent prospective human subject exposures. There were five exposure profiles, not previously found in the database, covering a wide parameter of ranges of altitude (18,000-35,000 ft), exposure time (180-360 min), prebreathe time (0-90 min), and activity level (rest-strenuous) that were used. The subjects were monitored for DCS symptoms and venous gas emboli. RESULTS: There were 30 subjects who were exposed to each of the 5 altitude profiles. The DCS incidence onset curves predicted by the model were not significantly different from the experimental values for all scenarios tested and were generally within +/- 5% of the actual values. CONCLUSION: A predictive altitude DCS model was successfully developed and validated.

The risk of altitude decompression sickness at 12,000 m and the effect of ascent rate.

INTRODUCTION: Loss of aircraft cabin pressurization can result in very rapid decompression rates. The literature contains reports of increased or unchanged levels of altitude decompression sickness (DCS) resulting from increasing the rate of decompression. We conducted two prospective exposure profiles to quantify the DCS risk at 12,192 m (40,000 ft), and to determine if there was a greater DCS hazard associated with a much higher rate of decompression than typically used during past DCS studies. METHODS: The 63 human subjects participated in 80 altitude chamber decompression exposures to a simulated altitude of 12,192 m (2.72 psia; 18.75 kPa) for 90 min, following preoxygenation with 100% oxygen for 90 min. Half of the subject-exposures involved an 8-min decompression (1,524 mpm; 5,000 fpm) and the other half experienced a 30-s decompression (mean of 24,384 mpm; 80,000 fpm). Throughout each ascent and exposure, subjects were seated at rest and breathed 100% oxygen. At altitude, they were monitored for precordial venous gas emboli (VGE) and DCS symptoms. RESULTS: The higher decompression rate yielded 55.0% DCS and 72.5% VGE and the lower rate produced 47.5% DCS and 65.0% VGE. Chi square and log rank tests based on the Kaplan-Meier analyses indicated no difference in the incidence or onset rate of DCS or VGE observed during the two profiles. CONCLUSION: Decompression rate to altitude up to 24,384 mpm was found not to have an effect on DCS risk at altitude. However, research is needed to define the DCS risk with decompression rates greater than 24,384 mpm. It was also found that the onset time to DCS symptoms decreases as altitude increases.

Gender not a factor for altitude decompression sickness risk.

INTRODUCTION: Early, retrospective reports of the incidence of altitude decompression sickness (DCS) during altitude chamber training exposures indicated that women were more susceptible than men. We hypothesized that a controlled, prospective study would show no significant difference. METHODS: We conducted 25 altitude chamber decompression exposure profiles. A total of 291 human subjects, 197 men and 94 women, underwent 961 exposures to simulated altitude for up to 8 h, using zero to 4 h of preoxygenation. Throughout the exposures, subjects breathed 100% oxygen, rested or performed mild or strenuous exercise, and were monitored for precordial venous gas emboli (VGE) and DCS symptoms. RESULTS: No significant differences in DCS incidence were observed between men (49.5%) and women (45.3%). However, VGE occurred at significantly higher rates among men than women under the same exposure conditions, 69.3% and 55.0% respectively. Women using hormonal contraception showed significantly greater susceptibility to DCS than those not using hormonal contraception during the latter two weeks of the menstrual cycle. Significantly higher DCS incidence was observed in the heaviest men, in women with the highest body fat, and in subjects with the highest body mass indices and lowest levels of fitness. CONCLUSION: No differences in altitude DCS incidence were observed between the sexes under our test conditions, although men developed VGE more often than women. Age and height showed no significant influence on DCS incidence, but persons of either sex with higher body mass index and lower physical fitness developed DCS more frequently.

Enhancement of preoxygenation for decompression sickness protection: effect of exercise duration.

INTRODUCTION: Since strenuous exercise for 10 min during preoxygenation was shown to provide better protection from decompression sickness (DCS) incidence than resting preoxygenation, a logical question was: would a longer period of strenuous exercise improve protection even further? HYPOTHESIS: Increased strenuous exercise duration during preoxygenation increases DCS protection. METHODS: There were 60 subjects, 30 men and 30 women, who were exposed to 9,144 m (4.3 psia) for 4 h while performing mild, upper body exercise. Before the exposures, each subject performed three preoxygenation profiles on different days in balanced order: a 90-min resting preoxygenation control; a 240-min resting preoxygenation control; and a 90-min preoxygenation including exercise during the first 15 min. The subjects were monitored at altitude for venous gas emboli (VGE) with an echo-imaging system and observed for signs and symptoms of DCS. RESULTS: There were no significant differences in occurrence of DCS following any of the three preoxygenation procedures. Results were also comparable to an earlier report of 42% DCS with a 60-min preoxygenation including a 10-min exercise. There was no difference between VGE incidence in the comparison of protection offered by a 90-min preoxygenation with or without 13 min of strenuous exercise. The DCS incidence following a 240-min resting preoxygenation, 40%, was higher than observed during NASA studies and nearly identical with the earlier 42% DCS after a 60-min preoxygenation including exercise during the first 10 min. CONCLUSION: The protection offered by a 10 min exercise in a 60-min preoxygenation was not increased with extension of the preoxygenation exercise period to 15 min in a 90-min preoxygenation, indicating an upper time limit to the beneficial effects of strenuous exercise.

The effect of repeated altitude exposures on the incidence of decompression sickness.

INTRODUCTION: Repeated altitude exposures in a single day occur during special operations parachute training, hypobaric chamber training, unpressurized flight, and extravehicular space activity. Inconsistent and contradictory information exists regarding the risk of decompression sickness (DCS) during such hypobaric exposures. HYPOTHESIS: We hypothesized that four short exposures to altitude with and without ground intervals would result in a lower incidence of DCS than a single exposure of equal duration. METHODS: The 32 subjects were exposed to 3 different hypobaric exposures--condition A: 2 h continuous exposure (control); condition B: four 30-min exposures with descent/ascent but no ground interval between the exposures; condition C: four 30-min exposures with descent/ascent and 60 min of ground interval breathing air between exposures. All exposures were to 25,000 ft with 100% oxygen breathing. Subjects were observed for symptoms of DCS, and precordial monitoring of venous gas emboli (VGE) was accomplished with a SONOS 1000 echo-imaging system. RESULTS: DCS occurred in 19 subjects during A (mean onset 70+/-29 min), 7 subjects in B (60+/-34 min), and 2 subjects in C (40+/-18 min). There was a significant difference in DCS incidence between B and A (p = 0.0015) and C and A (p = 0.0002), but no significant difference between B and C. There were 28 cases of VGE in A (mean onset 30+/-23 min), 21 in B (41+/-35 min), and 21 in C (41+/-32 min) with a significant onset curve difference between B and A and between C and A, but not between B and C. Exposure A resulted in four cases of serious respiratory/neurological symptoms, while B had one and C had none. All symptoms resolved during recompression to ground level. CONCLUSION: Data indicate that repeated simulated altitude exposures to 25,000 ft significantly reduce DCS and VGE incidence compared with a single continuous altitude exposure.