Limited Relationship Between Echocardiographic Measures and Electrocardiographic Markers of Left Ventricular Size in Healthy Children.

Pediatric ECG standards have been defined without echocardiographic confirmation of normal anatomy. The Pediatric Heart Network Normal Echocardiogram Z-score Project provides a racially diverse group of healthy children with normal echocardiograms. We hypothesized that ECG and echocardiographic measures of left ventricular (LV) dimensions are sufficiently correlated in healthy children to imply a clinically meaningful relationship. This was a secondary analysis of a previously described cohort including 2170 digital ECGs. The relationship between 6 ECG measures associated with LV size were analyzed with LV Mass (LVMass-z) and left ventricular end-diastolic volume (LVEDV-z) along with 11 additional parameters. Pearson or Spearman correlations were calculated for the 78 ECG-echocardiographic pairs with regression analyses assessing the variance in ECG measures explained by variation in LV dimensions and demographic variables. ECG/echocardiographic measurement correlations were significant and concordant in 41/78 (53%), though many were significant and discordant (13/78). Of the 6 ECG parameters, 5 correlated in the clinically predicted direction for LV Mass-z and LVEDV-z. Even when statistically significant, correlations were weak (0.05-0.24). R2 was higher for demographic variables than for echocardiographic measures or body surface area in all pairs, but remained weak (R2 ≤ 0.17). In a large cohort of healthy children, there was a positive association between echocardiographic measures of LV size and ECG measures of LVH. These correlations were weak and dependent on factors other than echocardiographic or patient derived variables. Thus, our data support deemphasizing the use of solitary, traditional measurement-based ECG markers traditionally thought to be characteristic of LVH as standalone indications for further cardiac evaluation of LVH in children and adolescents.

CdiA Effectors from Uropathogenic Escherichia coli Use Heterotrimeric Osmoporins as Receptors to Recognize Target Bacteria.

Many Gram-negative bacterial pathogens express contact-dependent growth inhibition (CDI) systems that promote cell-cell interaction. CDI+ bacteria express surface CdiA effector proteins, which transfer their C-terminal toxin domains into susceptible target cells upon binding to specific receptors. CDI+ cells also produce immunity proteins that neutralize the toxin domains delivered from neighboring siblings. Here, we show that CdiAEC536 from uropathogenic Escherichia coli 536 (EC536) uses OmpC and OmpF as receptors to recognize target bacteria. E. coli mutants lacking either ompF or ompC are resistant to CDIEC536-mediated growth inhibition, and both porins are required for target-cell adhesion to inhibitors that express CdiAEC536. Experiments with single-chain OmpF fusions indicate that the CdiAEC536 receptor is heterotrimeric OmpC-OmpF. Because the OmpC and OmpF porins are under selective pressure from bacteriophages and host immune systems, their surface-exposed loops vary between E. coli isolates. OmpC polymorphism has a significant impact on CDIEC536 mediated competition, with many E. coli isolates expressing alleles that are not recognized by CdiAEC536. Analyses of recombinant OmpC chimeras suggest that extracellular loops L4 and L5 are important recognition epitopes for CdiAEC536. Loops L4 and L5 also account for much of the sequence variability between E. coli OmpC proteins, raising the possibility that CDI contributes to the selective pressure driving OmpC diversification. We find that the most efficient CdiAEC536 receptors are encoded by isolates that carry the same cdi gene cluster as E. coli 536. Thus, it appears that CdiA effectors often bind preferentially to "self" receptors, thereby promoting interactions between sibling cells. As a consequence, these effector proteins cannot recognize nor suppress the growth of many potential competitors. These findings suggest that self-recognition and kin selection are important functions of CDI.

The F pilus mediates a novel pathway of CDI toxin import.

Contact-dependent growth inhibition (CDI) is a widespread form of inter-bacterial competition that requires direct cell-to-cell contact. CDI(+) inhibitor cells express CdiA effector proteins on their surface. CdiA binds to specific receptors on susceptible target bacteria and delivers a toxin derived from its C-terminal region (CdiA-CT). Here, we show that purified CdiA-CT(536) toxin from uropathogenic Escherichia coli 536 translocates into bacteria, thereby by-passing the requirement for cell-to-cell contact during toxin delivery. Genetic analyses demonstrate that the N-terminal domain of CdiA-CT(536) is necessary and sufficient for toxin import. The CdiA receptor plays no role in this import pathway; nor do the Tol and Ton systems, which are exploited to internalize colicin toxins. Instead, CdiA-CT(536) import requires conjugative F pili. We provide evidence that the N-terminal domain of CdiA-CT(536) interacts with F pilin, and that pilus retraction is critical for toxin import. This pathway is reminiscent of the strategy used by small RNA leviviruses to infect F(+) cells. We propose that CdiA-CT(536) mimics the pilin-binding maturation proteins of leviviruses, allowing the toxin to bind F pili and become internalized during pilus retraction.

Patient Sleep Quality in Acute Inpatient Rehabilitation.

BACKGROUND: Sleep is an important component of neurorehabilitation. This study evaluates sleep quality in the acute inpatient rehabilitation setting and is the first to compare sleep quality in acute rehabilitation versus the acute care hospital and home settings. OBJECTIVE: To assess patient sleep quality in the acute inpatient rehabilitation setting. DESIGN: Cross-sectional survey study. SETTING: Acute inpatient rehabilitation unit. PATIENTS: Seventy-three patients admitted to the acute rehabilitation unit participated in the study. INTERVENTIONS: A validated sleep questionnaire was provided on admission regarding sleep at home and in the acute care hospital. The questionnaire was repeated on discharge from the acute rehabilitation unit regarding sleep during their rehabilitation admission. MAIN OUTCOME MEASURES: Visual analog scale of sleep depth, falling asleep, number of awakenings, percentage of time awake, and quality of sleep were obtained through use of the Richards-Campbell Sleep Questionnaire. These values were averaged to obtain "overall sleep perception." An additional question on environmental noise was added. Scores ranged from 0 for "worst sleep possible" to 100 for "best sleep possible." RESULTS: Patients reported significantly better sleep in all domains and overall in the acute rehabilitation unit compared to the acute care hospital, with the exception of percentage of time awake. Patients also reported significantly better sleep depth but worse noise in the acute rehabilitation unit when compared to home. Similarly, patients reported significantly better sleep in all domains and overall at home in comparison to the acute care hospital with the exception of percentage of time awake. CONCLUSIONS: Patient in the acute rehabilitation unit experience sleep quality that matches their experience at home and exceeds that in the hospital.

The Effect of a Screen Protector on Blue Light Intensity Emitted from Different Hand-held Devices.

PURPOSE: In response to growing concern about the effect of blue light on ocular tissue, companies have created mobile device screen protectors to block blue light. This project evaluates one of these screen protectors' ability to reduce blue light intensity. METHODS: The intensity of light at 450 nm from an iPhone 8, iPhone X, and iPad was measured in a dark room. The averages of three measurements were taken with and without the screen protector at different distances, settings of brightness, and Apple's night shift (NS) mode. Results were analyzed using paired t-tests. RESULTS: At 33 cm, 100% brightness, and 0% NS, the screen protector decreased intensity by 43.9%, 32.3%, and 34.9% for the iPhone 8, iPhone X, and iPad, respectively. At 33 cm and 100% brightness, increasing NS mode from 0% to 100% decreased intensity by 81.2%, 84.2%, and 86.5%. At 33 cm without NS, decreasing the brightness from 100% to 0% decreased intensity by 99.5%, 99.8%, and 97.8%. CONCLUSIONS: The screen protector decreased the intensity at 450 nm for every setting other than those at 0% brightness. Decreasing brightness and applying NS mode were more effective in reducing blue light. More research is needed to determine the benefits of decreasing blue light exposure from electronic devices.

Cost-effective Alternative for Negative-pressure Wound Therapy.

BACKGROUND: Current predominantly used equipments for negative-pressure wound therapy (NPWT) are expensive. In current healthcare climate continually emphasizing cost containment, importance in developing more cost-effective alternatives cannot be understated. Previously, therapeutically equivalent methods of providing NPWT was demonstrated using just low-cost, universally available supplies, coined Gauze-SUCtion (GSUC). Here, we examine long-term potential financial savings of utilizing GSUC over commercialized products. METHODS: A retrospective cost analysis was performed at the University of Chicago Medical Center between 1999 and 2014. All NPWT was provided via either GSUC or commercialized vacuum-assisted closure (VAC, KCI) device. Sum of all material component costs were reviewed to determine theoretical average daily cost. For the VAC group, recorded institutional spend to KCI was also reviewed to determine actual daily cost. In the GSUC group, this figure was extrapolated using similar ratios. Labor costs for each method were determined using analysis from prior study. Patient demographics, etiology, wound location, and treatment length were also reviewed. RESULTS: Total of 35,871 days of NPWT was provided during the 15-year span. Theoretical average cost of VAC was $94.01/d versus $3.61/d for GSUC, whereas actual average was $111.18/d versus $4.26/d. Average labor cost was $20.11/dressing change versus $12.32. Combined, total cost of VAC therapy was estimated at $119,224 per every 1,000 days of therapy versus $9,188 for the GSUC. CONCLUSIONS: There is clear and significant cost savings from utilization of GSUC method of NPWT. Furthermore, the added advantage of being able to provide NPWT from universally accessible materials cannot be overstated.

Pyoderma gangrenosum: A case report of bilateral dorsal hand lesions and literature review of management.

Pyoderma gangrenosum is a great masquerader in wound diagnosis and management. Frequently misdiagnosed as a necrotizing infection, the elusive nature of its etiology and pathogenesis has thwarted the establishment of a standardized management algorithm, leaving immunosuppressant therapies as the mainstay of treatment. The present report describes a 61-year-old woman presenting with temporally discrete bilateral dorsal hand lesions successfully managed with distinctive multimodality therapies. The initial lesion was managed under the auspices of a necrotizing process using a combination of hyperbaric oxygen therapy and skin grafting with a negative-pressure dressing, both individually demonstrated to be effective for prompt wound stabilization and coverage. A subsequent contralateral hand lesion was similarly managed as a necrotizing infection before a diagnosis of pyoderma gangrenosum was considered. Stabilization and eventual resolution was achieved using intravenous and topical steroids followed by hyperbaric oxygen therapy, again highlighting the benefits of multimodality therapy in the setting of pyoderma gangrenosum.

La pyodermite gangréneuse provoque souvent de faux diagnostics et de mauvaises prises en charge des plaies. Elle est souvent diagnostiquée à tort comme une infection nécrosante, et la nature insaisissable de son étiologie et de sa pathogenèse contrecarre la création d'un algorithme de prise en charge standardisé, laissant les immunosuppresseurs comme pivots du traitement. Le présent rapport décrit le cas d'une femme de 61 ans qui a consulté en raison de lésions bilatérales du dos des mains discrètes temporelles, prises en charge avec succès par des thérapies multimodales distinctives. La lésion initiale a été traitée sous les auspices d'un processus nécrosant faisant appel à un mélange de thérapie par oxygène hyperbare et de greffe de la peau accompagnée d'un pansement en pression négative, car il est démontré que chacun de ces traitements stabilise et couvre rapidement la plaie avec efficacité. Une lésion controlatérale subséquente a été également prise en charge comme s'il s'agissait d'une lésion nécrosante avant qu'on envisage un diagnostic de pyodermite gangréneuse. Les médecins ont réussi à stabiliser, puis à résoudre le problème à l'aide de stéroïdes intraveineux et topiques suivis d'une thérapie par oxygène hyperbare, faisant de nouveau ressortir les avantages de la thérapie multimodale en présence d'une pyodermite gangréneuse.

Applications of biomaterials in plastic surgery.

The expansion of the application of biomaterials in plastic surgery has led to the increased availability of commercial products in recent years. This overview discusses soft tissue fillers, bioengineered skins, acellular dermal matrices, biomaterials for craniofacial surgery, and peripheral nerve repair. We summarize indications, properties, uses, types, advantages and disadvantages of some of the currently available products from each category. Finally, the current state of development in drug delivery system is also briefly summarized.

X box-binding protein 1 regulates angiogenesis in human pancreatic adenocarcinomas.

PURPOSE: Tumors encounter endoplasmic reticulum stress during tumor growth and activate an adaptive pathway known as the unfolded protein response (UPR). Because this pathway is induced by the tumor microenvironment, it is a promising target for cancer therapy. We have previously demonstrated that X-box binding protein 1 (XBP-1), a key regulator of the UPR, was required for survival under hypoxia and critical for tumor growth in tumor xenografts. In this study, we investigated the role of XBP-1 in regulating tumor angiogenesis. METHODS: We used an intradermal angiogenesis model to quantify the effect of XBP-1 on angiogenesis. We also used a human tumor xenograft model to assay for tumor growth delay. We determined vascular endothelial growth factor (VEGF) expression by quantitative polymerase chain reaction and ELISA. Finally, we stained human pancreatic adenocarcinoma specimens for XBP-1 expression and correlated the expression pattern of XBP-1 with CD31 (endothelial cell marker) expression. RESULTS: We demonstrated that XBP-1 is essential for angiogenesis during early tumor growth. Inhibiting XBP-1 expression by short-hairpin RNA sequence specific for XBP-1 reduced blood vessel formation in tumors from mouse embryonic fibroblast cells and human fibrosarcoma tumor cells (HT1080). Expressing a dominant-negative form of IRE1alpha also reduced blood vessel formation in tumors. Moreover, expression of spliced XBP-1 (XBP-1s) restored angiogenesis in IRE1alpha dominant-negative expressing cells. We further demonstrated that XBP-1-mediated angiogenesis does not depend on VEGF. CONCLUSIONS: We propose that the IRE1alpha-XBP-1 branch of the UPR modulates a complex proangiogenic, VEGF-independent response that depends on signals received from the tumor microenvironment.