Biomechanical Properties of Skin in Massive Weight Loss Patients

Background  

The aim of this study is to assess skin strength in MWL patients relative to control cosmetic abdominoplasty patients biophysically, biochemically, and histologically. Growing success of weight loss programs has brought about an increase in the MWL population. Skin quality is thought to be impaired by MWL, but there are no compelling studies that have fully addressed the structural mechanisms involved.     

Transurethral injection of bulking agent for treatment of failed mid-urethral sling procedures

Introduction and hypothesis  

We evaluated the efficacy of transurethral injection (TUI) for the treatment of recurrent or persistent stress urinary incontinence after mid-urethral sling (MUS) procedures.     

Vapor condensation with daytime radiative cooling

A radiative vapor condenser sheds heat in the form of infrared radiation and cools itself to below the ambient air temperature to produce liquid water from vapor. This effect has been known for centuries, and is exploited by some insects to survive in dry deserts. Humans have also been using radiative condensation for dew collection. However, all existing radiative vapor condensers must operate during the nighttime. Here, we develop daytime radiative condensers that continue to operate 24 h a day. These daytime radiative condensers can produce water from vapor under direct sunlight, without active consumption of energy. Combined with traditional passive cooling via convection and conduction, radiative cooling can substantially increase the performance of passive vapor condensation, which can be used for passive water extraction and purification technologies.

Energy and clean water are global challenges that are intertwined in an unfavorable way: even in areas where water is abundant, energy may not be available to purify it for human use (1, 2). There has been strong interest in developing passive technologies to purify or harvest water without using fuel or electricity. In this context, passive vapor condensation becomes particularly important because many passive water technologies go through the vapor phase of water in their harvesting or purification processes.Traditional vapor condensation technique is based on convective and conductive heat exchange with ambient environments. This technique is widely used in systems with hot vapors (3–6). However, with ever-increasing emphasis on passive systems, there are many situations in which warm- or even room-temperature vapor needs to be effectively condensed, such as extracting water from atmosphere (7–9) and warm vapor generated from high-efficiency solar evaporation (10). For vapor at such temperatures, most traditional condensers fail. For this reason, there is a clear need for a condensation technique to complement traditional condensers.A different technique is based on radiative vapor condensation. Darkling beetles in the Namib desert (11) use this technique to collect water. Their bodies function as a cooling surface by shedding thermal energy through midinfrared (mid-IR) radiation toward a clear nighttime sky, generating dew from humid air. This mechanism is also used by commercial radiative dew condensers (7–9). However, neither Namib beetle nor existing dew condensers can operate in the daytime (7). Those nighttime radiative condensers are incompatible with many emerging water technologies that require 24 h operation or direct access to sunlight.Recently, Fan et al. showed that passive radiative cooling to subambient temperatures can be realized even during the daytime, by integrating a high-efficiency solar reflector with a high-emissivity thermal emitter in the mid-IR atmospheric transparency window (12). Using this work as a basis, here we demonstrate a daytime radiative condenser. Compared to existing radiative vapor condensers (7–9), our condenser can function even in the presence of sunlight, which is essential for integration into passive water-harvesting systems that mainly operate during daytime.     

Computed tomographic evaluation of the role of craniofacial and upper airway morphology in obstructive sleep apnea in Chinese

OBJECTIVES: To evaluate the relationship between cephalometric parameters, upper airway morphological factors and obstructive sleep apnea (OSA) in Chinese subjects. DESIGN: Polysomnogram (PSG) were performed and scored using standard criteria. Supine lateral cephalometric parameters and pharyngeal cross-sectional areas at the level of velopharynx (VA) and hypopharynx (HA) were measured from computed tomographic scans. The roles of these parameters and other anthropometric/demographic characteristics in OSA (apnea hypopnea index, AHI > or = 5) and their relationship with severity of OSA were explored by multiple logistic and multinominal regression analysis. RESULTS: Ninety-two subjects, ranging from normal (n = 36), mild/moderate OSA (n = 34) to severe OSA (n = 22), were evaluated. Compared with normal subjects, OSA subjects were heavier (body mass index 27 vs. 24 kg/m2) and older (47 vs. 42 years of age); had smaller VA size and VA to HA ratio, lower positioned hyoid bone, longer and thicker soft palate, and more retropositioned mandible relative to maxilla. After controlling for body mass index and age, subjects with severe OSA (AHI > 30) had more retropositioned mandible relative to maxilla (odds ratio, OR 1.31, P = 0.044) and longer soft palate (OR 1.16, P = 0.01), while those with mild/moderate OSA had larger VA to HA ratio (OR 0.17, P = 0.018). CONCLUSIONS: Craniofacial factors and upper airway morphology contributed to severity of OSA in Chinese subjects. Having controlled for obesity, more retropositioned mandible was associated with more severe OSA.     

Riboflavin instability is a key factor underlying the requirement of a gut microbiota for mosquito development

We previously determined that several diets used to rear Aedes aegypti and other mosquito species support the development of larvae with a gut microbiota but do not support the development of axenic larvae. In contrast, axenic larvae have been shown to develop when fed other diets. To understand the mechanisms underlying this dichotomy, we developed a defined diet that could be manipulated in concert with microbiota composition and environmental conditions. Initial studies showed that axenic larvae could not grow under standard rearing conditions (27 °C, 16-h light: 8-h dark photoperiod) when fed a defined diet but could develop when maintained in darkness. Downstream assays identified riboflavin decay to lumichrome as the key factor that prevented axenic larvae from growing under standard conditions, while gut community members like Escherichia coli rescued development by being able to synthesize riboflavin. Earlier results showed that conventional and gnotobiotic but not axenic larvae exhibit midgut hypoxia under standard rearing conditions, which correlated with activation of several pathways with essential growth functions. In this study, axenic larvae in darkness also exhibited midgut hypoxia and activation of growth signaling but rapidly shifted to midgut normoxia and arrested growth in light, which indicated that gut hypoxia was not due to aerobic respiration by the gut microbiota but did depend on riboflavin that only resident microbes could provide under standard conditions. Overall, our results identify riboflavin provisioning as an essential function for the gut microbiota under most conditions A. aegypti larvae experience in the laboratory and field.

Diet crucially affects the health of all animals (1). Most animals have a gut microbiota that can also affect host health both positively and negatively (2–6). However, understanding of the mechanisms underlying the effects of the gut microbiota remains a major challenge. This is because animals often consume complex or variable diets, and harbor large, multimember microbial communities that can result in many interactions that hinder identification of the factors responsible for particular host responses (2, 6–11). Metaanalyses and multiomic approaches can provide inferential insights on how diet–microbe or microbe–microbe interactions affect hosts (11–18), but functional support can be difficult to generate if proposed mechanisms cannot be studied experimentally (2, 14). Thus, study systems where hosts can be reared on defined diets with or without a microbiota of known composition can significantly advance mechanistic insights by providing the means to control and manipulate dietary, microbial, and environmental variables that potentially affect a given host response (19–21).Mosquitoes are best known as insects that blood feed on humans and other vertebrates. Only adult-stage female mosquitoes blood feed, which is required for egg formation by most species (22). Blood feeding has also led to several mosquitoes evolving into vectors that can transmit disease-causing microbes between hosts (22). In contrast, the juvenile stages of all mosquitoes are aquatic, with most species feeding on detritivorous diets (22–24). Larvae hatch from eggs with no gut microbiota but quickly acquire relatively low-diversity communities from the environment by feeding (25). Most gut community members are aerobic or facultatively anaerobic bacteria in four phyla (Actinobacteria, Bacteroidetes, Firmicutes, Proteobacteria), although other microbes, such as fungi and apicomplexans, have also been identified (25–39). Gut community composition also commonly varies within and between species as a function of where larvae develop, diet, and other variables (28–30, 32, 34, 40–42).Aedes aegypti has a worldwide distribution in tropical and subtropical regions, and is the primary vector of the agents that cause yellow fever, dengue fever, and lymphatic filariasis in humans (43). Preferentially living in urban habitats, females lay eggs in water-holding containers with microbial communities, and larvae molt through four instars before pupating and emerging as adults (30, 35, 41, 43). Conventionally reared cultures with a gut microbiota are usually maintained in the laboratory under conditions that mimic natural habitats with rearing temperatures of 25 to 28 °C and a 12- to 16-h light: 8- to 12-h dark photoperiod (44–46). Most insects that require microbial partners for survival live on nutrient-poor diets where microbes provision nutrients that cannot be synthesized or produced in sufficient abundance by the host (3). Mosquito larvae can experience resource limitations in the field (23–25), but in the laboratory are reared on undefined, nutrient-rich diets, such as rodent chow, fish food flakes, or mixtures of materials like liver powder, fish meal, and yeast extract (44–46). Nonetheless, our previous studies indicated that axenic A. aegypti as well as other species consume but fail to grow beyond the first instar when fed several diets that support the development of nonsterile, conventionally reared larvae (30, 47–49). Escherichia coli and several other bacteria identified as gut community members could colonize the gut (producing monoxenic, gnotobiotic larvae) and rescue development, but feeding axenic larvae dead bacteria could not (30, 35, 47). The presence of a gut microbiota in conventional and gnotobiotic but not axenic larvae was also associated with midgut hypoxia and activation of several signaling pathways with growth functions (50, 51). Finally, our own previous results using a strain of E. coli susceptible to ampicillin (50), and more recently a method for clearing an auxotrophic strain of E. coli from gnotobiotic larvae (52), both showed that the proportion of individuals that develop into adults correlates with the duration that larvae have living bacteria in their gut.Altogether, the preceding results suggested that A. aegypti and several other mosquitoes require a gut microbiota for development. In contrast, another recent study showed that axenic A. aegypti larvae develop into adults, albeit more slowly than larvae with a gut microbiota, when fed diets comprised of autoclaved bovine liver powder (LP) and brewer’s yeast (Saccharomyces cerevisiae) extract (YE) or autoclaved LP, YE, and E. coli (EC) embedded in agar (53). This latter finding suggests the undefined dietary components used provide factors larvae require for development into adults, whereas a gut microbiota was also required to provide these factors under the conditions in which our own previous studies were conducted. The goal of this study was to identify what these factors are. Toward this end, we first assessed the growth of axenic A. aegypti when fed diets containing autoclaved LP, YE, and EC under different conditions. We then used this information to develop a defined diet that allowed us to systematically manipulate nutrient, microbial, and environmental variables. We report that the instability of riboflavin is a key factor underlying why A. aegypti larvae require a gut microbiota under most conditions experienced in the laboratory and field.     

Second allogeneic transplantation using umbilical cord blood for a patient with relapsed ALK+ anaplastic large cell lymphoma after allogeneic bone marrow transplantation in the era of ALK inhibitors: A case report

Rationale:Anaplastic lymphoma kinase (ALK) + anaplastic large cell lymphoma (ALCL) is considered as a good prognosis lymphoma. However, in an extremely rare subset of patients, ALK+ ALCL with leukemic presentations is known to be chemotherapy-resistant. Although several novel therapies have been tested, the standard therapy for relapsed/refractory ALK+ ALCL has not been established yet.Patient concerns:An 18-year-old female patient who had conventional chemotherapy- and Brentuximab Vedotin (BV)-resistant ALK+ ALCL with leukemic presentation. She was successfully treated with an ALK inhibitor, crizotinib. Crizotinib induced complete remission (CR) and bridged to allogeneic bone marrow transplantation (BMT).Diagnosis:However, her ALCL relapsed on day 60 after BMT and she developed high grade fever and lymphadenopathy.Intervention:Although crizotinib was given to the patient immediately after relapse, she developed grade 3 nausea and could not continue to take it. Then, we gave alectinib to the patient, which promptly induced sustained CR without any further chemotherapy. The patient received second stem cell transplantation using umbilical cord blood with myeloablative regimen in 2^nd CR.Outcomes:The patient has been in CR under maintenance therapy of alectinib for more than 16 months.Lessons:Both ALK inhibitors demonstrated drastic efficacy for our patient who had chemotherapy- and BV-resistant ALK+ ALCL with leukemic presentation. Alectinib showed less gastro-intestinal toxicity than crizotinib and the patient was able to take it even at the relatively early phase of stem cell transplantation.     

Five-year clinical outcomes of the first Korean-made sirolimus-eluting coronary stent with abluminal biodegradable polymer

This study evaluated the 5-year clinical outcomes of the Genoss DES, the first Korean-made sirolimus-eluting coronary stent with abluminal biodegradable polymer.We previously conducted the first-in-patient prospective, multicenter, randomized trial with a 1:1 ratio of patients using the Genoss DES and Promus Element stents; the angiographic and clinical outcomes of the Genoss DES stent were comparable to those of the Promus Element stent. The primary endpoint was major adverse cardiac events (MACE), which was a composite of death, myocardial infarction (MI), and target lesion revascularization (TLR) at 5 years.We enrolled 38 patients in the Genoss DES group and 39 in the Promus Element group. Thirty-eight patients (100%) from the Genoss DES group and 38 (97.4%) from the Promus Element group were followed up at 5 years. The rates of MACE (5.3% vs 12.8%, P = .431), death (5.3% vs 10.3%, P = .675), TLR (2.6% vs 2.6%, P = 1.000), and target vessel revascularization (TVR) (7.9% vs 2.6%, P = .358) at 5 years did not differ significantly between the groups. No TLR or target vessel revascularization was reported from years 1 to 5 after the index procedure, and no MI or stent thrombosis occurred in either group during 5 years.The biodegradable polymer Genoss DES and durable polymer Promus Element stents showed comparable low rates of MACE at the 5-year clinical follow-up.     

A prediction rule for clinical diagnosis of severe acute respiratory syndrome.

A prospective study was undertaken to identify clinical, radiographical, haematological and biochemical profiles of severe acute respiratory syndrome (SARS) patients. A prediction rule, which demarcates low from high risk patients for SARS in an outbreak situation was developed. A total of 295 patients with unexplained respiratory illnesses, admitted to Queen Mary Hospital, Hong Kong SAR, China, in March to July 2003, were evaluated for clinical, radiological, haematological and alanine transaminase (ALT) data daily for 3 days after hospitalisation. In total, 44 cases were subsequently confirmed to have SARS by RT-PCR (68.2%) and serology (100%). The scoring system of attributing 11, 10, 3, 3 and 3 points to the presence of independent risk factors, namely: epidemiological link, radiographical deterioration, myalgia, lymphopenia and elevated ALT respectively, generated high and low-risk (total score 11-30 and 0-10, respectively) groups for SARS. The sensitivity and specificity of this prediction rule in positively identifying a SARS patient were 97.7 and 81.3%, respectively. The positive and negative predictive values were 47.8 and 99.5%, respectively. The prediction rule appears to be helpful in assessing suspected patients with severe acute respiratory syndrome at the bedside, and should be further validated in other severe acute respiratory syndrome cohorts.     

Arterial stiffness and vascular load in heart failure

Vascular load is an important determinant of ventricular function. This is particularly true of the failing heart, which is exquisitely load-sensitive. Vascular load comprises 2 major components: resistive load, which arises primarily at the arteriolar resistance vessels, and pulsatile load, which is primarily determined by aortic stiffness and early return of reflected waves from the periphery to the heart. Assessment of pulsatile load is gaining increasing prominence as evidence grows of a significant pathophysiologic role for arterial stiffness in cardiovascular disease, including heart failure. Assessment of arterial stiffness and vascular load is reviewed here. The importance of optimal ventricular-vascular coupling to maximize the efficiency of cardiac ejection is discussed. Current knowledge of arterial stiffness, vascular load, and ventricular-vascular coupling in systolic heart failure and in heart failure with a normal ejection fraction ("diastolic failure") is described. Reducing aortic stiffness may form an important future therapeutic target in patients with heart failure.     

Is the Bladder “An Unreliable Witness” in Elderly Males with Persistent Lower Urinary Tract Symptoms?

Aim: We sought to study the usefulness of lower urinary tract symptoms and postvoid residual urine volume in the diagnosis of voiding dysfunction in elderly men. Methods: The symptoms and postvoid residual urine volume of 126 men aged 65 years or older referred for urodynamic studies were obtained. Their accuracy in the diagnosis of detrusor instability, bladder outlet obstruction and impaired detrusor contractility was quantified. Results: For the diagnosis of detrusor instability, urgency and urge incontinence with frequency and/or nocturia had a sensitivity of 73.0% and a specificity of 60.0%. For the diagnosis of bladder outlet obstruction, poor stream with frequency and/or nocturia had a sensitivity of 51.9% and a specificity of 71.6%. Using poor stream and residual urine volume of more than 50 ml occurring together, the sensitivity was 31.1% and specificity was 89.7%. For the diagnosis of impaired detrusor contractility, poor stream had a sensitivity of 44.8% and a specificity of 56.7%. With residual urine volume of more than 50 ml, a sensitivity of 96.6% and specificity of 80.4% was obtained. Conclusion: Based on our findings, we conclude that the bladder does appear to be an “ unreliable witness ” in elderly men for the diagnosis of bladder outlet obstruction, though this is less so with impaired detrusor contractility. No conclusion can be drawn for the detrusor instability as we did not use ambulatory urodynamic studies.