Combining the geometry of folded paper with liquid-infused polymer surfaces to concentrate and localize bacterial solutions.

Point-of-care (POC) detection and diagnostic platforms provide critical information about health and safety conditions in austere and resource-limited settings in which medical, military, and disaster relief operations are conducted. In this work, low-cost paper materials commonly used in POC devices are coated with liquid-infused polymer surfaces and folded to produce geometries that precisely localize complex liquid samples undergoing concentration by evaporation. Liquid-infused polymer surfaces were fabricated by infusing silicone-coated paper with a chemically compatible polydimethylsiloxane oil to create a liquid overlayer. Tests on these surfaces showed no remaining bacterial cells after exposure to a sliding droplet containing a concentrated solution of Escherichia coli or Staphylococcus aureus, while samples without a liquid layer showed adhesion of both microdroplets and individual bacterial cells. Folding of the paper substrates with liquid-infused polymer surfaces into several functional 3D geometries enabled a clean separation and simultaneous concentration of a liquid containing rhodamine dye into discrete, predefined locations. When used with bacteria, which are known for their ability to adhere to nearly any surface type, functional geometries with liquid-infused polymer surfaces concentrated the cells at levels significantly higher than geometries with dry control surfaces. These results show the potential of synergistically combining paper-based materials with liquid-infused polymer surfaces for the manipulation and handling of complex samples, which may help the future engineering of POC devices.

Menstrual cycle and oral contraceptive use do not modify postexercise heat loss responses.

It is unknown whether menstrual cycle or oral contraceptive (OC) use influences nonthermal control of postexercise heat loss responses. We evaluated the effect of menstrual cycle and OC use on the activation of heat loss responses during a passive heating protocol performed pre- and postexercise. Women without OC (n = 8) underwent pre- and postexercise passive heating during the early follicular phase (FP) and midluteal phase (LP). Women with OC (n = 8) underwent testing during the active pill consumption (high exogenous hormone phase, HH) and placebo (low exogenous hormone phase, LH) weeks. After a 60-min habituation at 26 degrees C, subjects donned a liquid conditioned suit. Mean skin temperature was clamped at approximately 32.5 degrees C for approximately 15 min and then gradually increased, and the absolute esophageal temperature at which the onset of forearm vasodilation (Th(vd)) and upper back sweating (Th(sw)) were noted. Subjects then cycled for 30 min at 75% Vo(2 peak) followed by a 15-min seated recovery. A second passive heating was then performed to establish postexercise values for Th(vd) and Th(sw). Between 2 and 15 min postexercise, mean arterial pressure (MAP) remained significantly below baseline (P < 0.05) by 10 +/- 1 and 11 +/- 1 mmHg for the FP/LH and LP/HH, respectively. MAP was not different between cycle phases. During LP/HH, Th(vd) was 0.16 +/- 0.24 degrees C greater than FP/LH preexercise (P = 0.020) and 0.15 +/- 0.23 degrees C greater than FP/LH postexercise (P = 0.017). During LP/HH, Th(sw) was 0.17 +/- 0.23 degrees C greater than FP/LH preexercise (P = 0.016) and 0.18 +/- 0.16 degrees C greater than FP/LH postexercise (P = 0.001). Postexercise thresholds were significantly greater (P < or = 0.001) than preexercise during both FP/LH (Th(vd), 0.22 +/- 0.03 degrees C; Th(sw), 0.13 +/- 0.03 degrees C) and LP/HH (Th(vd), 0.21 +/- 0.03 degrees C; Th(sw), 0.14 +/- 0.03 degrees C); however, the effect of exercise was similar between LP/HH and FP/LH. No effect of OC use was observed. We conclude that neither menstrual cycle nor OC use modifies the magnitude of the postexercise elevation in Th(vd) and Th(sw).

Postexercise heat loss and hemodynamic responses during head-down tilt are similar between genders.

PURPOSE: We evaluated the hypothesis that during recovery from dynamic exercise in the 15 degrees head-down tilt (HDT) position, the attenuation of the fall in mean arterial pressure (MAP), cutaneous vascular conductance (CVC), and sweat rate, and the augmentation of the rate of esophageal temperature (T(es)) decay relative to the upright seated (URS) posture, would be different between males and females. METHODS: Fourteen subjects (seven males, seven females) performed two experimental protocols: 1) 15 min of cycle ergometry at 75% VO2peak and then 60 min of recovery in the URS posture; or 2) 15 min of cycle ergometry at 75% VO2peak and then 60 min of recovery in the 15 degrees HDT position. Mean skin temperature, Tes, CVC, sweat rate, cardiac output (CO), stroke volume (SV), heart rate (HR), total peripheral resistance (TPR), and MAP were recorded at baseline; end of exercise; 2 min, 5 min, 8 min, 12 min, 15 min, and 20 min after exercise; and every 5 min until the end of recovery (60 min). RESULTS: During recovery from exercise, we observed significantly greater values for MAP, CVC, and sweat rate with HDT in comparison with the URS recovery posture (P

15 degrees head-down tilt attenuates the postexercise reduction in cutaneous vascular conductance and sweating and decreases esophageal temperature recovery time.

The following study examined the effect of 15 degrees head-down tilt (HDT) on postexercise heat loss and hemodynamic responses. We tested the hypothesis that recovery from dynamic exercise in the HDT position would attenuate the reduction in the heat loss responses of cutaneous vascular conductance (CVC) and sweating relative to upright seated (URS) recovery in association with an augmented hemodynamic response and an increased rate of core temperature decay. Seven male subjects performed the following three experimental protocols: 1) 60 min in the URS posture followed by 60 min in the 15 degrees HDT position; 2) 15 min of cycle ergometry at 75% of their predetermined V(O2 peak) followed by 60 min of recovery in the URS posture; or 3) 15 min of cycle ergometry at 75% of their predetermined V(O2 peak) followed by 60 min of recovery in the 15 degrees HDT position. Mean skin temperature, esophageal temperature (T(es)), skin blood flow, sweat rate, cardiac output (CO), stroke volume (SV), heart rate (HR), total peripheral resistance, and mean arterial pressure (MAP) were recorded at baseline, end exercise, 2, 5, 8, 12, 15, and 20 min, and every 5 min until end of recovery (60 min). Without preceding exercise, HDT decreased HR and increased SV (P < or = 0.05). During recovery after exercise, a significantly greater MAP, SV, CVC, and sweat rate and a significantly lower HR were found with HDT compared with URS posture (P < or = 0.05). Subsequently, a significantly lower T(es) was observed with HDT after 15 min of recovery onward (P < or = 0.05). At the end of 60 min of recovery, T(es) remained significantly elevated above baseline with URS (P < or = 0.05); however, T(es) returned to baseline with HDT. In conclusion, extended recovery from dynamic exercise in the 15 degrees HDT position attenuates the reduction in CVC and sweating, thereby significantly increasing the rate of T(es) decay compared with recovery in the URS posture.

Factors Associated with Breastfeeding Initiation in Adolescent Pregnancies: A Cohort Study.

PURPOSE: Adolescent mothers have a lower breastfeeding rate than adult women. The objective is to determine the association between multiple high-risk characteristics of pregnant adolescents with intention and initiation of breastfeeding. METHODS: We conducted a retrospective population-based cohort study in Ontario (2006-2012) using the Better Outcomes Registry & Network (BORN) database. Breastfeeding outcomes of adolescent women (younger than 20 years) with a singleton live-born infant at term gestation (37 weeks or greater) were analyzed. The χ(2) and independent-sample t tests were used where appropriate. A multivariate logistic regression analysis was also performed. RESULTS: This study included 22,023 adolescent women with complete breastfeeding information. Almost half (48.8%, n = 10,749) exclusively breastfed their infant at time of hospital discharge. Breastfeeding was significantly more likely in the older adolescents (odds ratio 1.10); other factors significantly associated with breastfeeding included intention to breastfeed, prenatal classes attendance, living in a higher-income neighborhood, having a spontaneous vaginal delivery, being a nonsmoker, not using substances during pregnancy, and not having any preexisting health problems or obstetrical complications (P < .0001). A significant interaction between smoking and intention to breastfeed was identified. Intention to breastfeed was found to be protective against the reduction in breastfeeding seen with smoking. CONCLUSION: This large-cohort study confirms that high-risk factors are associated with lower breastfeeding in Canadian adolescent term singleton births. Breastfeeding intention is a very important driver of breastfeeding. These findings highlight the importance of early multidisciplinary adolescent pregnancy care targeting these risks factors and education in order to improve breastfeeding rates in this population.

Imiquimod 5% cream treatment for rapidly progressive genital condyloma in a 3-year-old girl.

BACKGROUND: The incidence of genital warts in children has increased in the last 50 years. Although pediatric genital warts may resolve spontaneously, the treatment of extensive perianal genital warts in children can be challenging. Imiquimod, although not approved in the pediatric population, may avoid the pain or extensive scarring associated with other treatment modalities. CASE: A 3-year-old female was scheduled for surgical resection of genital warts. At surgery, she had extensive condylomas that had progressed rapidly from initial presentation. They were not amenable to surgical treatment due to concerns of incomplete resection, post-operative pain, and genital scarring. After 6 weeks of imiquimod treatment, the condylomatous lesions had completely resolved with minimal side effects. SUMMARY AND CONCLUSION: Imiquimod 5% cream is an effective treatment option for children with extensive and rapidly progressive perianal warts and is associated with minimal side effects. Its use should be considered in children with extensive condyloma in order to avoid the pain and possible scarring associated with other approved treatment modalities.