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Study Design Retrospective cohort studyObjective The aim of this study was to determine the relative importance and predicative power of the Hospital Frailty Risk Score (HFRS) on unplanned 30-day readmission after surgical intervention for metastatic spinal column tumors.Methods All adult patients undergoing surgery for metastatic spinal column tumor were identified in the Nationwide Readmission Database from the years 2016 to 2018. Patients were categorized into 3 cohorts based on the criteria of the HFRS: Low(<5), Intermediate(5-14.9), and High(≥ 15). Random Forest (RF) classification was used to construct predictive models for 30-day patient readmission. Model performance was examined using the area under the receiver operating curve (AUC), and the Mean Decrease Gini (MDG) metric was used to quantify and rank features by relative importance.Results There were 4346 patients included. The proportion of patients who required any readmission were higher among the Intermediate and High frailty cohorts when compared to the Low frailty cohort (Low:33.9%vs. Intermediate:39.3%vs. High:39.2%, P < .001). An RF classifier was trained to predict 30-day readmission on all features (AUC = .60) and architecturally equivalent model trained using only ten features with highest MDG (AUC = .59). Both models found frailty to have the highest importance in predicting risk of readmission. On multivariate regression analysis, Intermediate frailty [OR:1.32, CI(1.06,1.64), P = .012] was found to be an independent predictor of unplanned 30-day readmission.Conclusion Our study utilizes machine learning approaches and predictive modeling to identify frailty as a significant risk-factor that contributes to unplanned 30-day readmission after spine surgery for metastatic spinal column metastases.

Biodiversity net gain (BNG), designed to reverse the decline of biodiversity and put back more than is lost through development, is legally mandated as part of the 2021 Environment Act. [...]

I have the opportunity to see things many people in the industry do not. I am fortunate that my job responsibilities allow me unrestricted access to manufacturing facilities of sign [...]

ABSTRACTCommunity colleges serve the most diverse student populations in higher education yet have some of the lowest levels of faculty diversity in higher education. Retaining community college student cohorts through transfer/graduation is a goal, yet attaining this goal has been elusive, particularly for underrepresented minority (URM) community college students. Few studies have explored the impact of faculty diversity on the successful retention of URM community college students. This study used archival data for 120 public community colleges from the Integrated Postsecondary Education Data System (IPEDS) to calculate a Diversity Score for each college and ranked them by their overall level of faculty racial/ethnic variance to quantify the relationship between faculty diversity and student graduation, transfer, and drop-out rates. The findings suggest that there is a significant strong positive relationship between graduation, transfer, and drop-out rates for URM students of all race/ethnic categories when there are increases in faculty diversity. Exposure to a diverse faculty produces different outcomes in URM students.

The rapid integration of artificial intelligence (AI) in dermatology shows promise for support of clinical practice and democratization of diagnosis access. Significant limitations and ethical concerns persist, however. Despite growing research into AI's effectiveness in identifying skin conditions, fewer studies have explored its ability to accurately diagnose hair disorders.

Turfgrass covers more land in the continental US than the next 10 agricultural crops combined; approximately40,000,000 acres of turf covers 1.9% of the total land. This fact, coupled with turf's [...]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.amjsurg.2006.01.001 Byline: Martin G. Schwacha (a), Gerald McGwin (b)(c), Charles B. Hutchinson (b), James M. Cross (b), Paul A. MacLennan (b), Loring W. Rue (b) Keywords: Morphine; Immunosuppression; Sepsis Abstract: Immune and infectious complications are associated with burn injury. Opiate analgesics also can induce similar complications, however, their impact on postburn infectious complications is unknown. Author Affiliation: (a) Center for Surgical Research and Departments of Surgery, Microbiology, and Pathology, University of Alabama at Birmingham, G094 Volker Hall, 1670 University Blvd., Birmingham, AL 35294-0019, USA (b) Center for Injury Sciences, Section of Trauma, Burns, and Surgical Critical Care, Division of General Surgery, Department of Surgery, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA (c) Department of Epidemiology and International Health, School of Public Health, University of Alabama at Birmingham, Birmingham, AL, USA Article History: Received 22 August 2005; Revised 1 January 2006

The National Institute on Drug Abuse (NIDA) had convened a meeting of experts in placental biology to review cutting-edge research with the mission to translate existing information to new clinical and research initiatives in the drug abuse field. Thus, their presentations and research recommendations resulting from the workshop discussions are reported.

ABSTRACTSince the discovery of bovine spongiform encephalopathy (BSE), researchers have orally challenged cattle with infected brain material to study various aspects of disease pathogenesis. Unlike most other pathogens, oral BSE challenge does not always result in the expected clinical presentation and pathology. In a recent study, steers were challenged orally with BSE and all developed clinical signs and were sacrificed and tested. However, despite a similar incubation and clinical presentation, one of the steers did not have detectable PrPScin its brain. Samples from this animal were analysed for genetic differences as well as for the presence of in vitro PrPScseeding activity or infectivity to determine the BSE status of this animal and the potential reasons that it was different. Seeding activity was detected in the brainstem of the abnormal steer but it was approximately one million times less than that found in the normal BSE positive steers. Intra-cranial challenge of bovinized transgenic mice resulted in no transmission of disease. The abnormal steer had different genetic sequences in non-coding regions of the PRNP gene but detection of similar genotypes in Canadian BSE field cases, that showed the expected brain pathology, suggested these differences may not be the primary cause of the abnormal result. Breed composition analysis showed a higher Hereford content in the abnormal steer as well as in two Canadian atypical BSE field cases and several additional abnormal experimental animals. This study could point towards a possible impact of breed composition on BSE pathogenesis.

Levamisole is a veterinary antihelminthic, chemotherapeutic agent, and immunomodulator that also is used as an adulterant and cutting agent in cocaine distribution. This drug may potentiate the sympathomimetic actions of cocaine and can cause neutropenia, agranulocytosis, purpuric retiform lesions, and skin necrosis. This article describes two cases of suspected levamisole-induced vasculitis. No standardized diagnostic or treatment algorithm exists for this challenging condition. Diagnosis and treatment require a multidisciplinary team approach.

This study explores the role of the sales force in formulating and executing marketing strategies. Specifically, the relationships between sales force activities such as providing information about customer needs, hiring and training salespeople, and assessing new market segments and four marketing strategies (market penetration, product development, market development, diversification) are examined. Results indicate that the use of sales force activities is related to a firm's strategic choices, and that the relationships vary by firm size and type of offering., Introduction As firms pursue increases in revenue and profits, they select from a variety of marketing strategies. Implicit in these strategic choices is the need for appropriate implementation and control [...]

The article refers to the Mother Hubbard Suit filed in 1940 by the U.S. Department of Justice's Antitrust Division and discusses research on marketing "divorcement" in the petroleum industry. The outcome of a case started in 1950 by the Antitrust Division, which charged seven integrated oil companies with conspiracy to restrain competition and create a monopoly, is expected to impact the direction of public policy. The issues are: jobber margins; vertical integration; divorcement of marketing from the production, refining, and transportation of petroleum products; the distinction between subsidization and price discrimination when supply is abundant; and "net-back" to the refinery. The study found that divorcement leads to higher prices and inefficiency.

The placenta is crucial for a successful pregnancy and the health of both the fetus and the pregnant woman. However, how the human trophoblast lineage is regulated, including the categorization of the placental cell subtypes is poorly understood. Here we performed single-cell RNA sequencing (RNA-seq) on sorted placental cells from first- and second-trimester human placentas. New subtypes of cells of the known cytotrophoblast cells (CTBs), extravillous trophoblast cells (EVTs), Hofbauer cells, and mesenchymal stromal cells were identified and cell-type-specific gene signatures were defined. Functionally, this study revealed many previously unknown functions of the human placenta. Notably, 102 polypeptide hormone genes were found to be expressed by various subtypes of placental cells, which suggests a complex and significant role of these hormones in regulating fetal growth and adaptations of maternal physiology to pregnancy. These results document human placental trophoblast differentiation at single-cell resolution and thus advance our understanding of human placentation during the early stage of pregnancy.

In trauma, admission rapid thrombelastography (rTEG) has been shown to predict in-hospital thromboembolic events, guide treatment of coagulopathy, and identify likely to require large volume resuscitations. We sought to evaluate the use of rTEG in describing the coagulation status of major burn patients at admission and assess whether rTEG values predicted resuscitation volumes and patient outcomes. This is a retrospective study of all patients admitted to our Burn intensive care unit between January 2010 and December 2012. We excluded those with < 15% TBSA burns, < 18 years of age, and with concomitant injuries requiring admission to the Trauma intensive care unit. Previously published and validated cut points for hypocoagulable (activated clotting time = 128; k-time = 2.5; angle = 60; mA = 55; LY30 = 3%) and hypercoagulable (mA = 65) rTEG values were used. Supra-normal burn resuscitation was defined as = 5.0?mL/kg/TBSA. Statistical analyses were conducted using STATA 13.1. Sixty-five patients met inclusion with a median age of 45 years, 74% male and 49% white. Median TBSA was 38% with 14% having third-degree burns. Sixty percentage of patients were hypercoagulable on admission, while 24% were hypocoagulable. rTEG values predicted increased 24-hour resuscitation volumes, as well as plasma and platelet transfusions (P< 0.05). Controlling for age, TBSA, and base deficit, admission rTEG = 128 predicted a 5-fold increased likelihood of supra-normal resuscitation. In addition, an angle < 60 predicted in-hospital mortality. While the majority of severely burned patients arrive hypercoagulable, one-quarter are hypocoagulable and have increased resuscitation and transfusion requirements. Moreover, those with admission activated clotting time = 128 are at 5-fold increased risk of supra-normal resuscitation.

Many types of multinucleated cells (syncytia) generated by cell-cell fusion are post-mitotic, but it remains unclear how this state is maintained and why. Here, we utilized the fluorescent ubiquitination-based cell-cycle indicator (Fucci) reporter system to show that human placental trophoblast cells were all in the G0 phase before they fuse. Expression of the fusogenic protein (fusogen) Syncytin-2 was confined to G0 cells. Overexpression of Syncytin-2 in cycling cells overrode the cell-cycle restriction and enabled fusion of cells in the S/G2/M phases but resulted in the unstable syncytia retaining mitotic features. The Syncytin-2-induced syncytia were functionally compromised with respect to pathogen defense and hormone secretion. We found that, during trophoblast fusion, the cell-cycle inhibitor p21 interacted with the GCM1 transcription factor, and this complex bound to the promoter of Syncytin-2and promoted its transcription. These findings demonstrate that G0-restricted Syncytin-2 expression is a prerequisite for development of functional post-mitotic syncytia.

N629D KCNH2is a human missense long-QT2 mutation. Previously, we reported that the N629DN629D mutation embryos disrupted cardiac looping, right ventricle development, and ablated IKractivity at E9.5. The present study evaluates the role of KCNH2 in vasculogenesis.

Radiation burn injuries account for 0.2% of burn injury admissions. Treatment of radiation burns remains challenging because of unpredictable inflammatory changes and soft tissue necrosis. Conventional treatment consists of multistaged surgical procedures. Here, we present a case of an Iridium-192 exposure treated nonoperatively. A 23-year-old man presented with a 7-day-old, less than 1% TBSA radiation burn to his right hand. He initially sought treatment at an outside hospital and plastic surgeon's office postinjury days 2 and 3. He later presented to our facility because of worsening pain, edema, and discoloration. He was admitted and hospitalized for 15 days. Narcotics were initiated and wound care consisted of daily antibiotic ointment and petroleum gauze dressings. We continued dexamethasone and pentoxyfilline for 1 week. He underwent nineteen 90-minute treatments of hyperbaric oxygen therapy during an 8-week period. He had complete wound healing 1 month postdischarge. This case report provides background on radiation burn injuries and applicability of nonoperative management in treating radiation burn injuries. Furthermore, it encourages the development of individualized treatment plans, consideration of the use of hyperbaric oxygen therapy, referral to a burn center, and consulting radiation experts for guidance.

Severe burn induces rapid skeletal muscle proteolysis after the injury, which persists for up to 1 year and results in skeletal muscle atrophy despite dietary and rehabilitative interventions. The purpose of this research was to determine acute changes in gene expression of skeletal muscle mass regulators postburn injury. Specimens were obtained for biopsy from the vastus lateralis of a nonburned leg of eight burned subjects (6M, 2F: 34.8 ± 2.7 years: 29.9 ± 3.1% TBSA burn) at 5.1 ± 1.1 days postburn injury and from matched controls. mRNA expression of cytokines and receptors in the tumor necrosis factor-a (TNF-a) and interleukin-6 (IL-6) families, and the ubiquitin proteasome E3 ligases, atrogin-1 and MuRF-1, was determined. TNF receptor 1A was over 3.5-fold higher in burn. Expression of TNF-like weak inducer of apoptosis and its receptor were over 1.6 and 6.0-fold higher in burn. IL-6, IL-6 receptor, and glycoprotein 130 were elevated in burned subjects with IL-6 receptor over 13-fold higher. The level of suppressor of cytokine signaling-3 was also increased nearly 6-fold in burn. Atrogin-1 and MuRF-1 were more than 4- and 3-fold higher in burn. These results demonstrate for the first time that severe burn in humans has a remarkable impact on gene expression in skeletal muscle of a nonburned limb of genes that promote inflammation and proteolysis. Because these changes likely contribute to the acute skeletal muscle atrophy in areas not directly affected by the burn, in the future it will be important to determine the responsible systemic cues.

Water uptake and usage are important factors affecting plant adaption to drought stress. The objective of this study was to determine morphological and physiological traits of the grass canopy and root systems governing plant water relations in association with genetic variability in tall fescue (Festuca arundinaceaSchreb.) drought resistance. Grass canopy and root traits (turf quality [TQ], relative water content [RWC], evapotranspiration [ET] rate, single‐leaf net photosynthesis rate [Pn], stomatal conductance [gs], stomatal aperture [SA] and density, transpiration rate [Tr], root length [RL], root dry weight [RDW], root viability or root electrolyte leakage [REL], and specific root length [SRL]) were examined in seven tall fescue genotypes during drought stress in two repeated trials of a controlled‐environment growth chamber study (May–June and September–October 2011). All these canopy and root traits exhibited significant variability in drought responses among tall fescue genotypes while Pn, gs, Tr, RL, RDW, and SRL also varied among genotypes under well‐watered conditions. Correlation and principal component analysis of traits associated with genetic variability in drought resistance demonstrated that the superior turf performance (higher TQ) and leaf hydration status (higher RWC) under drought stress were associated with sustained stomatal opening (greater SA and gs) and water use rate (higher Tr and ET), maintaining higher Pn as well as the development of the root system with higher viability (lower REL) and finer diameter (higher SRL). Integration of canopy and root traits controlling both water consumption and water uptake will facilitate breeding improvement of drought resistance in tall fescue and other cool‐season grass species.

Severe burn injuries lead to a prolonged hypercatabolic state resulting in dramatic loss of skeletal muscle mass. Postburn muscle loss is well documented but the molecular signaling cascade preceding atrophy is not. The purpose of this study is to determine the response to burn injury of signaling pathways driving muscle inflammation and protein metabolism. Muscle biopsies were collected in the early flow phase after burn injury from the vastus lateralis of a noninjured leg in patients with 20 to 60% TBSA burns and compared with uninjured, matched controls. Circulating levels of proinflammatory cytokines were also compared. Immunoblotting was performed to determine the protein levels of key signaling components for translation initiation, proteolysis, and tumor necrosis factor/nuclear factor kappa B (NF?B)and interleukin (IL)-6/STAT3 signaling. Burn subjects had significantly higher levels of circulating proinflammatory cytokines, with no difference in muscle STAT3 activity and lower NF?B activity. No differences were found in any translational signaling components. Regarding proteolytic signaling in burn, calpain-2 was 47% higher, calpastatin tended to be lower, and total ubiquitination was substantially higher. Surprisingly, a systemic proinflammatory response 3 to 10 days postburn did not lead to elevated muscle STAT3 or NF?B signaling. Signaling molecules governing translation initiation were unaffected, whereas indices of calcium-mediated proteolysis and ubiquitin-proteasome activity were upregulated. These novel findings are the first in humans to suggest that the net catabolic effect of burn injury in skeletal muscle (ie, atrophy) may be mediated, at least during the early flow phase, almost entirely by an increased proteolytic activity in the absence of suppressed protein synthesis signaling.

Approximately 50% of fatal and 15% of nonfatal burn-injured patients have detectable blood alcohol content (BAC) at the time of admission, and it is hypothesized that alcohol exacerbates burn-related immunosuppression. The purpose of this study was to evaluate the association between BAC and infectious complications in burn patients. The study population consisted of 1161 burn patients admitted to a large academic burn center between January 1998 and June 2007. Patients were categorized into no BAC (0.0 g/100 ml), low/moderate BAC (>0.0 and <0.1 g/100 ml) and high BAC (=0.1 g/100 ml) groups based on BAC at time of admission. Risk ratios (RRs) and 95% confidence intervals (CIs) were calculated for associations between pneumonia, sepsis, urinary tract infection, line infection, and wound infection and BAC, adjusted for total burn surface area and inhalation injury. Relative to no BAC patients, both low/moderate and high BAC patients had nonsignificantly increased risk for most infectious complications. High BAC patients were at significantly increased risk for any infectious complication (RR 2.06, CI 1.25–3.41) and pneumonia (RR 2.06, CI 1.04–4.09) and a nonsignificantly increased risk of urinary tract infection (RR 2.12, CI 0.0.94–4.78). Results suggest that preinjury alcohol consumption places patients at an increased risk for infectious complications, most notably pneumonia. Further studies examining the relationship between alcohol and pneumonia among burn patients will help elucidate the reason for the increased risk observed in the current study and suggest ways to prevent infection for this particular subgroup of burn patients.

Recent studies show an apparent survival advantage associated with the administration of higher cumulative ratios of fresh frozen plasma (FFP) to packed red blood cells (PRBC). It remains unclear how temporal factors and survival bias may influence these results. The objective of this study was to evaluate the temporal relationship between blood product ratios and mortality in massively transfused trauma patients.

Metallic heat exchanger coated catalyst (MHXCC)-based reformers have been proposed. If successful, the reformers based on this concept are compact in size, with smaller pressure drop, better shock and vibration resistance, quicker startup, faster kinetics, lower operating temperature and longer durability than conventional reformers. In addition, the metallic substrate-coated WGS and PrOx catalysts have some advantages over either pellet-based or ceramic substrate-coated ones for the downstream CO cleanup. In order to develop our next generations of fuel processing systems that have these advantages, a series of works were carried out at Nuvera's micro-reactors for providing the most fundamental data to the design of these kinds of new reformers. Excellent agreement between theoretical and measured equilibrium shows that the reactor setup is suitable for thermodynamic and kinetic studies for MHXCC technology development. Our studies indicate that proper and adequate heating both horizontally from furnace of catalyst bed and vertically from preheat are critical for steam reforming studies using MHXCC-based catalysts. FeCrAlloy is a good substrate for catalyst washcoating, and no catalyst loss was observed for all of the tested catalysts by weight comparisons before and after testing. Methane conversion, kinetics, thermodynamic product distributions are very useful pieces of information for future designs of metal substrate-coated reformers. A power law rate expression accurately models the data for each catalyst. MHXCC technologies developed in the laboratory have been successfully applied to full scale fuel processors for H2 production.

Acute adrenal insufficiency (AI) is an uncommon disorder among critically ill burn patients, which can often go unrecognized. The goal of the current study is to identify risk factors for AI among patients who have sustained severe thermal injury. A case–control study was conducted among all adult patients admitted to the intensive care unit of the University of Alabama at Birmingham Burn Center during a 7-year period (1997–2003). All burn patients who developed AI were selected as cases (n = 26), and a random sample of those ICU patients who did not develop AI were selected as controls (n = 56). Two variables demonstrated significant independent associations with the risk of AI. Patients who developed AI were older than controls (50 vs. 46 years, respectively) and suffered a significantly greater area of thermal injury when compared with controls (mean percentage of total body surface area burned for cases and controls 45.5% and 25.4%, respectively). Over half (59.1%) of the patients with AI died compared with only 14.6% of controls (P< 0.0001). The development of AI appears to be associated with a greater TBSA burn and older age. After severe thermal injury, the diagnosis of AI substantially increases the risk of death. A better understanding of factors that predispose burn patients to AI may aid in earlier diagnosis, initiation of therapy, and improved outcomes.

Nuvera's state-of-the-art on-board fuel processor is a very compact system with catalyst and heat exchanger volume of 80 liters, with a maximum power input of 215 kWth, and with hydrogen efficiencies capabilities above 77%. For our fuel processor we use four distinct reaction zones, ATR-HTS-LTS- PrOx. The entire fuel processor, with balance of plant controls components, can be packaged in a volume of 150-liter designed to fit in the floor of a vehicle.The on-board fuel processor design is quite flexible; it can operate on a number of fuels including gasoline, diesel, ethanol, methanol and gas fuels, and the fuel processor can be either scaled up or scaled down for other applications, for example, APU systems. Also, the on- board fuel processors were integrated successfully with Nuvera's automotive PEM fuel cell stacks. A fuel processor start-up time of less than 4 minutes was achieved to the target value for the fuel cell.

The author presents a response to the article "Some Thoughts on London Trees" by Mark Lutyens, which appeared in a previous issue of the journal. The author focuses on the ways in which trees can cause damage, discusses legal claims and liability for property damage caused by trees, and cites specific legal cases involving damage caused by trees.

We sought to present the epidemiology of intentional burns, both deliberate self-inflicted burns and assault burns. Patient records from the University of Alabama at Birmingham Burn Center were reviewed retrospectively. Information pertaining to demographic and injury characteristics were obtained. Ninety-six patients with intentional burns were identified. Patients sustaining intentional burn injury had larger mean TBSA burned (26.1% vs 13.8%), longer mean hospital length of stay (19.9 days vs 13.2 days), higher incidence of inhalational injury (20.8% vs 8.7%), higher rate of mortality (20.0% vs 9.8%), and were more likely to have an elevated blood alcohol content (14.6% vs 7%) when compared with all other burn patients. Patients with deliberate self-burns were more likely to be men (85.7% vs 55.7%) and more likely to have a positive drug screen test than assault burn patients (11.4% vs 0%). Patients who suffer intentional burns tend to have more severe burns and experience worse outcomes.

Severe burns induce pathophysiologic problems, among them catabolism of lean mass, leading to protracted hospitalization and prolonged recovery. Oxandrolone is an anabolic agent shown to decrease lean mass catabolism and improve wound healing in the severely burned patients. We enrolled 81 adult subjects with burns 20% to 60% TBSA in a multicenter trial testing the effects of oxandrolone on length of hospital stay. Subjects were randomized between oxandrolone 10 mg every 12 hours or placebo. The study was stopped halfway through projected enrollment because of a significant difference between groups found on planned interim analysis. We found that length of stay was shorter in the oxandrolone group (31.6 ± 3.1 days) than placebo (43.3 ± 5.3 days; P< .05). This difference strengthened when deaths were excluded and hospital stay was indexed to burn size (1.24 ± 0.15 days/% TBSA burned vs 0.87 ± 0.05 days/% TBSA burned, P < .05). We conclude that treatment using oxandrolone should be considered for use in the severely burned while hepatic transaminases are monitored.

Although an increased risk of death among female patients suffering thermal injury has been noted, the differential influence of age has received little attention. Because experimental evidence suggests that sex hormones influence the immune response to thermal injury, an age-related sex influence on patient mortality is biologically plausible as the hormone milieu changes with the onset of menopause. The goal of this study was to estimate the association between sex and mortality after thermal injury in a large, population-based sample. The National Trauma Data Bank™ yielded data for more than 6200 burn patients 20 years of age or older. Logistic regression was used to calculate mortality odds ratios (OR) with 95% confidence intervals (CIs) for men relative to women, both overall and by age. Adjustments for age, race, burn etiology, percent body surface area burned, comorbid conditions, and inhalation injury were performed. For the overall study population, the adjusted risk of death was approximately 30% lower for males (OR 0.67, 95% CI 0.52–0.87). Within age strata, the adjusted association was statistically significant only in those aged 20 to 34 years (OR 0.45; 95% CI 0.24–0.87); 35 to 49 years (OR 0.71; 95% CI 0.39–1.30); 50 to 64 years (OR 0.55; 95% CI 0.31–1.00); and 65 years or older (OR 0.85; 95% CI 0.57–1.27). The results of the present study not only indicate that women have an increased odds of mortality after thermal injury but also demonstrate a differential effect of age on the association between sex and mortality. On the basis of the findings of the present study as well as the results of experimental studies, further clinical research is needed to investigate the impact of sex hormones on mortality among burn patients.

The placenta is essential for sustaining the growth of the fetus during gestation, and defects in its function result in fetal growth restriction or, if more severe, fetal death. Several molecular pathways have been identified that are essential for development of the placenta, and mouse mutants offer new insights into the cell biology of placental development and physiology of nutrient transport.

The placenta is an organ that clinicians and embryologists would all agree is important for pregnancy success. Unfortunately, however, they too often ignore it when they are exploring causes for embryonic, fetal and perinatal complications. The core function of the placenta is to mediate the transport of nutrients between the maternal and fetal circulation, but it also has critical endocrine functions that alter different maternal physiological systems in order to sustain pregnancy. Both its development and ongoing functions can be dynamically regulated by environmental factors, including nutrient status and tissue oxygenation. In recent years, mainstream attention has begun to shift onto the placenta and it is now becoming clear that placental pathology is associated with several complications in human and animal pregnancies, including embryonic lethality, fetal growth restriction, pre-eclampsia and the high rates of fetal deaths observed after nuclear transfer (cloning).

The uterine bed undergoes remarkable changes during pregnancy, including proliferation and decidualization of the uterine stroma and remodeling and angiogenesis of the maternal vasculature. Fetal-derived trophoblast giant cells invade into the uterus where they gain access to the maternal blood circulation to ensure sufficient nutrient supply of the embryo. In serial sections through early- to mid-gestation conceptuses, we have determined the exact distance of trophoblast invasion and the expression of angiogenic, vasodilatory, and anticoagulative factors that are likely to influence remodeling and redirection of the maternal circulatory system. Trophoblast derivatives were detected at a distance as far as ~300 μm from the placental border, where they are allocated exclusively along the mid-line of the decidua. The farthest invading cells characteristically expressed proliferin and proliferin-related protein, hormones that affect endothelial cell migration and vascularization. Occasionally, these cells replaced the normal vascular endothelium and acquired a “pseudo-endothelial” shape. Complete vascular disintegration was observed 50–80 μm outside of the placental border where maternal blood was entirely lined by a trophoblast giant cell-derived network of blood sinuses. This transition in blood space lining correlated with trophoblast expression of various vasodilatory and anticoagulative factors that are likely to promote blood flow toward the placenta. Analysis of teratocarcinoma-like tumors demonstrated that trophoblast giant cell-induced promotion and redirection of blood flow is not restricted to the uterine environment. These results show that trophoblast giant cells have the intrinsic capacity to attract and increase blood flow and to gradually displace the vascular endothelium resulting in the formation of canals entirely lined by trophoblast cells. Developmental Dynamics 227:185–191, 2003. © 2003 Wiley-Liss, Inc.

The placenta is a highly specialized organ whose primary function is to promote the exchange of nutrients and oxygen between maternal and fetal blood, essential for survival and growth of the baby. The surface area for nutrient transport is a highly convoluted villous structure that forms by branching morphogenesis. In mice, this process begins after embryonic day 8.5, following attachment of allantoic mesoderm to the chorion, and continues through the end of gestation. Gene targeting studies in mice have identified a large number of genes that are essential for chorioallantoic development to give rise to the layer of the placenta called the labyrinth. Collectively, these studies reveal that a number of signaling pathways regulate four distinct phases of labyrinth development: chorioallantoic attachment (involving VCAM1 and its receptor ?4 integrin, Bmp57, and Wnt7b, as well as the cochaperone Mrj), initiation of branching (involving the Gcm1 transcription factor to select sites of branch initiation), extension of villous branching (involving FGF, EGF, and HGFMet signaling, through the Grb2Sos1Mek1p38? MAPK pathway), followed by vascularization of the villous tree. The restricted expression andor action of the signaling components indicate that a series of intercellular interactions regulate chorioallantoic development.

The purpose of this study was to evaluate differences in mortality among adult burn patients over a 25-year period according to age. All patients admitted to a regional burn center between 1973 and 1997 were divided into three age groups (18–34, 35–54, and 55 and older), and mortality rates were compared over time. Between 1973 and 1997, the proportion of patients in each age group remained consistent, as did the type of burns. The average total body surface area burned declined steadily from 31.6% in the 1970s to 18.2% in the late 1990s. The absolute change in mortality was small (7.7%), moderate (16.3%), and large (30.2%) in the young, middle-aged, and old, respectively. However, the relative change demonstrated the opposite pattern. The results of this study suggest that declines in mortality among adult burn patients have occurred across the age spectrum over the past 25 years.

Clinical and experimental studies have demonstrated higher mortality following nonthermal trauma among males compared with females. To date, few clinical retrospective studies have focused on gender differences in outcome following burn injury with respect to age. All patients admitted to the University of Alabama at Birmingham (UAB) Burn Center between January 1994 and December 2000 were selected for inclusion in the study. Gender differences in demographic, clinical, and outcome characteristics were compared. Unadjusted and adjusted odds ratios (ORs) and 95 confidence intervals (CIs) were calculated for the association between mortality and gender, both overall and stratified by age. Over the 7-year study period, 1229 males and 382 females were admitted to the UAB Burn Center, and mortality rates were 7.2 and 13.4, respectively (P0.0002). Female patients were more likely to be older, of the black race, and in poorer health. In addition, females were more likely to suffer flame and scald burns. The association between mortality and gender was modified by age. Up to age 60, mortality rates among females were over twice that of males (OR 2.3, 95 CI 1.4–3.8); however, no difference was noted among those 60 and older (OR 0.9, 95 CI 0.5–1.6). These associations persisted following adjustment for potentially confounding variables. Causes and timing of death were similar for males and females. Women less than 60 years of age who sustain burn injuries have an increased risk of death compared with males. Differences in the natural history of nonthermal trauma and burn injury may provide insight regarding these divergent findings.

The purpose of this study was to present the epidemiology of thermal burn fatalities in the workplace in the United States between 1992 and 1999. Data on fatal thermal burn injuries in the United States between 1992 through 1999 were obtained from the Bureau of Labor Statistics Census of Fatal Occupational Injuries. Between 1992 and 1999, 1,189 fatal thermal burns occurred in the workplace (0.11 deaths/100,000 workers per year). Mortality increased with age, with those over 65 years of age having the greatest rate of death (0.20/100,000). Workers in the mining industry and transportation and public utilities had the highest rates of fatal thermal burns. Occupational categories with the highest rates included “extractive occupations” (eg, miners, explosives workers) and “transportation and material movers” (eg, truck drivers). The specific occupations with the highest rates were airplane pilots and navigators, furnace, kiln, and oven operators, and firefighters. Most decedents were operating vehicles or involved in “other transportation operations” at the time of the incident. The majority of injurious incidents occurred on “industrial premises” or the “street and highway.” Efforts to prevent fatal occupational thermal burn injuries should focus on older workers and those in occupations with frequent exposure to potential sources of thermal injury. Further study of nonfatal thermal burns in the workplace is needed because patterns of fatal burn injury may not reflect patterns of occupational burn injury overall.

Electron beam irradiations of aqueous solutions containing 15–30 mg/L of nitrobenzene at 60 kGy dose removed 78% of the contaminant. Three mononitrophenols were detected as by-products of electron beam treatment of nitrobenzene. A mixed culture enriched on a mixture of 2-, 3-, and 4-nitrophenol degraded both the residual nitrobenzene and the nitrophenol products. Percentage removal of nitrobenzene increased with increasing electron beam dose. This observation led to the conceptual design of a two-stage electron beam microbial process for degradation of nitrobenzene. Three groups of pure isolates were characterized from the mixed culture based on their abilities to grow on cor- responding nitrophenol substrates: Group A, 2NP⁻3NP⁻4NP⁺; Group B, 2NP⁺3NP⁺4NP⁻; and Group C, 2NP⁻3NP⁺4NP⁻. Bacteria that grew on 3-NP transformed nitrobenzene into ammonia in the electron beam-treated nitrobenzene samples. © 2001 John Wiley & Sons, Inc. Biotechnol Bioeng 73: 306–312, 2001.

We have recently demonstrated that in quiescent fibroblasts protein kinase C (PKC) ε95is phosphorylated at Ser729, Ser703, and Thr566and that upon passage of quiescent cells phosphorylation at Ser729is lost, giving rise to PKCε87. Ser729may be rephosphorylated later, suggesting cycling between PKCε87and PKCε95. Here we show that the dephosphorylation at Ser729is insensitive to okadaic acid, calyculin, ascomycin C, and cyclosporin A, suggesting that dephosphorylation at this site is not mediated through protein phosphatases 1, 2A or 2B. We demonstrate that this dephosphorylation at Ser729requires serum and cell readhesion and is sensitive to rapamycin, PD98059, chelerythrine, and Ro-31–8220. These results suggest that the phosphorylation status of Ser729in the hydrophobic domain at Ser729is regulated independently of the phosphorylation status of other sites in PKCε, by a mTOR-sensitive phosphatase. The mitogen-activated protein kinase pathway and PKC are also implicated in regulating the dephosphorylation at Ser729.

The basic helix-loop-helix transcription factor gene Hand1has been implicated in development of the heart. However, the early lethality of Hand1-null mutant mouse embryos has precluded a precise understanding of its function. In this study, we have generated Hand1homozygous mutant ES cells and performed in vitrodifferentiation experiments and chimeric analysis to study the role of Hand1function during cardiac development. Hand1-null ES cells were able to differentiate into beating cardiomyocytes in vitrothat expressed cardiac myosin and several cardiac-specific transcripts including Nkx2-5,α-cardiac actin,and the myofilament genes myosin light chain 2aand 2v.In chimeras derived from Hand1-null ES cells and ROSA26embryos, mutant cells were underrepresented in the left caudal region of the linear heart tube at E8.0. By E9.5, after cardiac looping, mutant cells were underrepresented in the anterior region of the outer curvature of the left ventricular myocardium, but did contribute to other parts of the left ventricle and to other cardiac chambers. These results imply that Hand1is not essential for differentiation of ventricular cardiomyocytes. Hand1-null cells were also underrepresented in several other regions of later embryos, including the rhombencephalic neural tube that was associated with a deficiency of mutant cells in the neural crest cell-derived cardiac outflow tract and first branchial arch. In summary, Hand1has cell-autonomous functions during cardiac morphogenesis in both mesodermal and neural crest derivatives.

Both vancomycin and thirdgeneration cephalosporin use are believed to contribute to a rise in vancomycinresistant enterococci VRE infections. In 1998, the largest number of VRE infections in our hospital occurred in the traumaburn intensive care unit TBICU, accounting for nearly 20 of hospital infections. In an attempt to control the VRE infection rate, antibiotic protocols for prophylaxis, empiric, and definitive therapy were initiated during the final quarter of 1998 to minimize cephalosporin use by the introduction of piperacillintazobactam. Therefore, we undertook a study of the VRE infection rate for the TBICU in relation to vancomycin, piperacillintazobactam, piperacillin, thirdgeneration cephalosporin, and total cephalosporin use before and after efforts to limit cephalosporins. These data were compared to those in the medical and surgical intensive care units. During 1998, seven VRE infections occurred in the TBICU. Following initiation of antibiotic protocols, one case of VRE infection occurred in the subsequent month and no cases in the 17 months since. The decrease in the VRE infection rate corresponded with a significant increase in the use of piperacillintazobactam and a reduction in thirdgeneration and total cephalosporin use. In contrast, cephalosporin use in the medical and surgical intensive care units remains significantly higher than in the TBICU, and neither unit has had a reduction in their VRE infection rates.