Concomitant injuries are an important determinant of outcome of high-grade blunt hepatic trauma

BACKGROUND: Little is known about the clinical importance of concomitant injuries in polytraumatized patients with high-grade blunt liver injury. A retrospective single-centre study was performed to investigate the safety of non-operative management of liver injury and the impact of concomitant intra- and extra-abdominal injuries on clinical outcome. METHODS: Some 183 patients with blunt liver injury were admitted to Berne University Hospital, Switzerland, between January 2000 and December 2006. Grade 3-5 injuries were considered to be high grade. RESULTS: Immediate laparotomy was required by 35 patients (19.1 per cent), owing to extrahepatic intra-abdominal injury (splenic and vascular injuries, perforations) in 21 cases. The mortality rate was 16.9 per cent; 22 of the 31 deaths were due to concomitant lesions. Of 81 patients with high-grade liver injury, 63 (78 per cent) were managed without surgery; liver-related and extra-abdominal complication rates in these patients were 11 and 17 per cent respectively. Grades 4 and 5 liver injury were associated with hepatic-related and extra-abdominal complications. CONCLUSION: Concomitant injuries are a major determinant of outcome in patients with blunt hepatic injury and should be given high priority by trauma surgeons. An algorithm for the management of blunt liver injury is proposed.

Major bleeding risk in anticoagulated patients receiving concomitant antiplatelet therapy: a prospective study

INTRODUCTION Current literature suggesting a higher bleeding risk during combination therapy compared to oral anticoagulation alone is primarily based on retrospective studies or specific populations. We aimed to prospectively evaluate whether unselected medical patients on oral anticoagulation have an increased risk of bleeding when on concomitant antiplatelet therapy. MATERIAL AND METHODS We prospectively studied consecutive adult medical patients who were discharged on oral anticoagulants between 01/2008 and 03/2009 from a Swiss university hospital. The primary outcome was the time to a first major bleed on oral anticoagulation within 12 months, adjusted for age, international normalized ratio target, number of medications, and history of myocardial infarction and major bleeding. RESULTS Among the 515 included anticoagulated patients, the incidence rate of a first major bleed was 8.2 per 100 patient-years. Overall, 161 patients (31.3%) were on both anticoagulant and antiplatelet therapy, and these patients had a similar incidence rate of major bleeding compared to patients on oral anticoagulation alone (7.6 vs. 8.4 per 100 patient-years, P=0.81). In a multivariate analysis, the association of concomitant antiplatelet therapy with the risk of major bleeding was not statistically significant (hazard ratio 0.89, 95% confidence interval, 0.37-2.10). CONCLUSIONS The risk of bleeding in patients receiving oral anticoagulants combined with antiplatelet therapy was similar to patients receiving oral anticoagulants alone, suggesting that the incremental bleeding risk of combination therapy might not be clinically significant.

Concomitant lipopolysaccharide-induced transfer of blood-derived components including immunoglobulins into milk

During a mammary immune response, the integrity of the blood-milk barrier is negatively affected and becomes leaky. The aim of the present study was to demonstrate the blood origin, and to investigate changes in the concentration, of various constituents including immunoglobulins in blood and milk during the early phase of lipopolysaccharide (LPS)-induced mastitis. Five lactating dairy cows received continuous β-hydroxybutyrate (BHBA) clamp infusions to maintain elevated BHBA blood concentrations (1.5 to 2.0 mmol/L) from 48 h before and 8h after LPS administration. One udder quarter was infused with 200 μg of Escherichia coli LPS. A second quarter served as control. Milk and blood samples were taken hourly for 8h postchallenge (PC). The somatic cell count in LPS-challenged quarters was increased from 4h PC to the end of the experiment compared with control quarters. In LPS-challenged quarters, l-lactate, BHBA, lactate dehydrogenase (LDH), IgG(1), and IgG(2) were increased at 3h PC and remained elevated until the end of experiment (8h PC) compared with control quarters. In addition, the optical density values in milk in a nonquantitative ELISA for antibodies directed against bluetongue virus (used as a measure of nonspecific antibody transfer; all animals were vaccinated) increased and, thus, indicates an increase in these antibodies in response to LPS treatment. l-Lactate concentration also increased in blood 2h PC and in the milk of control quarters during the experiment from 3h PC. A second experiment was conducted in vitro to investigate a possible contribution from destructed milk cells to l-lactate concentration and activity of LDH in milk. Aliquots of milk samples (n=8) were frozen (-20°C) or disrupted with ultrasound, respectively. Freeze thawing and ultrasound treatment increased LDH in milk samples, but had no effect on l-lactate concentrations. Results suggest that intramammary infusion of LPS induces a systemic response, as evidenced by an elevation of blood l-lactate concentration. The concomitant changes of all investigated components suggest that they were blood derived. However, the increase in blood components in the milk is not necessarily supportive of the mammary immune system, and likely a side effect of reduced blood-milk barrier integrity.

Aortic valve replacement and concomitant procedures with the Perceval valve: results of European trials.

BACKGROUND The Perceval (Sorin Group, Milan, Italy) is a self-anchoring sutureless aortic valve prosthesis. We report the short- to midterm results of combined aortic valve replacement (AVR) with concomitant procedures in elderly patients undergoing operation as part of 3 consecutive prospective multicenter European studies. METHODS From April 2007 to February 2013, 243 patients (mean age, 79.7 ± 5.1 years; female patients, 61%; median EuroSCORE, 9%) underwent AVR with concomitant procedures. The concomitant procedures were coronary artery bypass grafting (CABG) (182 cases), septal myectomy (21 cases), CABG + other procedures (18 cases), and 22 other procedures. Primary and secondary end points included implant feasibility and safety (for mortality and morbidity) and efficacy (New York Heart Association [NYHA] class improvement and hemodynamic results) of the prosthesis at the different follow-up periods. Data were expressed as mean ± standard deviation. Kaplan-Meier analysis was performed for survival analysis. RESULTS Mean aortic cross-clamp and extracorporeal circulation (ECC) times were 50.7 ± 22.8 minutes and 78.9 ± 32.3 minutes, respectively. Thirty-day mortality was 2.1%. Mean postoperative gradient and effective orifice area were 10.1 ± 4.7 mm Hg and 1.5 ± 0.4 cm(2) and 8.9 ± 5.6 mm Hg and 1.6 ± 0.4 cm(2), respectively, at 1 year. There were early explantations, 4 of which resulted from paravalvular leaks. One additional valve explantation resulted from aortic root bleeding, probably caused by excessively extensive decalcification. In the late period, there was 1 mild paravalvular leak and no intravalvular insufficiency. No migration, dislodgement, or degeneration of the valve occurred during follow-up. Median follow-up was 444 days. CONCLUSIONS These trials confirm the safety and efficacy of the Perceval sutureless aortic valve, especially in elderly patients requiring AVR + concomitant procedures. In this patient group, sutureless valves may be advantageous compared to transcatheter valve implantations as concomitant procedures other than percutaneous coronary artery angioplasty are not always possible in the latter.

Variance estimation in ranked set sampling using a concomitant variable

We propose a nonparametric variance estimator when ranked set sampling (RSS) and judgment post stratification (JPS) are applied by measuring a concomitant variable. Our proposed estimator is obtained by conditioning on observed concomitant values and using nonparametric kernel regression.

Concomitant Mycobacterium tuberculosis infection and type 2 diabetes: A descriptive model with global health implications

The type 2 diabetes (diabetes) pandemic is recognized as a threat to tuberculosis (TB) control worldwide. This secondary data analysis project estimated the contribution of diabetes to TB in a binational community on the Texas-Mexico border where both diseases occur. Newly-diagnosed TB patients > 20 years of age were prospectively enrolled at Texas-Mexico border clinics between January 2006 and November 2008. Upon enrollment, information regarding social, demographic, and medical risks for TB was collected at interview, including self-reported diabetes. In addition, self-reported diabetes was supported by blood-confirmation according to guidelines published by the American Diabetes Association (ADA). For this project, data was compared to existing statistics for TB incidence and diabetes prevalence from the corresponding general populations of each study site to estimate the relative and attributable risks of diabetes to TB. In concordance with historical sociodemographic data provided for TB patients with self-reported diabetes, our TB patients with diabetes also lacked the risk factors traditionally associated with TB (alcohol abuse, drug abuse, history of incarceration, and HIV infection); instead, the majority of our TB patients with diabetes were characterized by overweight/obesity, chronic hyperglycemia, and older median age. In addition, diabetes prevalence among our TB patients was significantly higher than in the corresponding general populations. Findings of this study will help accurately characterize TB patients with diabetes, thus aiding in the timely recognition and diagnosis of TB in a population not traditionally viewed as at-risk. We provide epidemiological and biological evidence that diabetes continues to be an increasingly important risk factor for TB.^

Clostridium difficile infection (CDI): Clinical outcomes associated with concomitant non-CDI antibiotic use

This research examined the relationship between concomitant non-CDI antibiotic use and complications arising due to Clostridium difficile infection. To observe the hypothesized association, 160 total CDI patients between the ages of 50-90 were selected, 80 exposed to concomitant antibiotics and 80 unexposed. Samples were matched based upon their age and Horn's index, a severity score for underlying illness. Patients were de-identified by a third party, and analyzed retrospectively for differences between the two groups. In addition, patients exposed to broad spectrum antibiotics at the time of CDI treatment were further studied to demonstrate whether antibiotics had any effect on CDI complications. Between the two groups, the outcomes of interest (recurrent CDI, refractory CDI, mortality, ICU stay, and length of hospitalization) were not associated with concomitant antibiotic use at the time of CDI therapy. However, within the exposed population, certain classes of antibiotics such as cephalosporin, antifungals, and tetracyclines were more common in patients compared to other types of therapy. In addition, days of therapy provided evidence that sustained use of antibiotics affected CDI (p = 0.08), although a more robust sample size and additional study would be needed. Finally, refractory CDI was found to be potentially overestimated within the exposed population due to the possibility of antibiotic-associated diarrhea.^

Description and analysis of variation in dairy product and concomitant nutrient purchases between Hispanic and non -Hispanic households using a panel of shoppers' purchase records

The purpose of this research was development of a method of estimating nutrient availability in populations as approximated by supermarket purchase records. Demographic information describing 12,516 panel households was obtained from a marketing and advertising program operated by H. E. Butt Grocery Company of San Antonio, Texas. A non-probability sample of 2,161 households meeting expenditure criteria was selected and all purchases of dairy products for this sample of households were organized into a database constructed to facilitate the retrieval, aggregation, and analysis of dairy product purchases and their nutrient contents. Two hypotheses were tested: (1) no difference would be found between Hispanic and non-Hispanic purchases of dairy product categories during the study period and (2) no difference would be found between Hispanic and non-Hispanic purchases of nutrients contained in those dairy products during the thirteen-week study period.^ Food purchase records were used to estimate nutrient exposure on a weekly, per capita basis for Hispanic and non-Hispanic households by linking some 40,000 dairy purchase Universal Product code (UPC) numbers with food composition values contained in USDA Handbook 8-1. Results of this study suggest Hispanic sample households consistently purchased fewer dairy products than did non-Hispanic sample households and consequently had fewer nutrients available from dairy purchases. While weekly expenditures for dairy products among the sample households remained relatively constant during the study period, shifts in the types of dairy products purchased were observed. The effect of ethnicity on dairy product and nutrient purchases was significant over the thirteen-week period. A database consisting of customer, household, and purchase information can be developed to successfully associate food item UPC numbers with a standard reference of food composition to estimate nutrient availability in a population over extended periods of time. ^

(Table 1) Productivity characteristics of phytoplankton and some concomitant factors in the Kara Sea in September 1993

Primary production in water column (P_p) varied from 107 to 312 mg C/m**2/day in Yenisey Bay: from 25 to 63 mg C/m**2/day in Obskaya Guba: and from 20 to 359 mg C/m**2/day in the open sea, that is: in the western Kara Sea and Ob-Yenisey shoals. The average concentration of chlorophyll a in the photosynthesis layer (C_ph) ranged from 0.2 to 1.8 mg/m**3 in these two regions, lower than in the estuaries of Ob (1.6-21.7 mg/m**3) and Yenisey (2.0-5.2 mg/m**3) Rivers. An inverse relation between surface salinity (S) and chlorophyll concentration (C_s) and chlorophyll concentration in the photosynthesis layer was found for all of the regions. The highest values of C_s and C_ph (0.8-22 mg/m**3) were measured at S<10 ppt, and the lowest values (0.2-0.8 mg/m**3) at S>22 ppt. A similar correlation of S with values of Pp occurred only in the Yenisey Bay and offshore regions. Obtained results agree well with the "outwelling" hypothesis. It states that large part of organic matter produced in estuaries is not used in estuarine trophic chains but is transported into adjacent sea areas and increases their productivity. Low values of Pp in the study regions may be attributed to such unfavorable factors as deficiency in nutrients, low temperature and turbidity, and lack of solar radiation.

Selective killing of preneoplastic and neoplastic cells by methotrexate with leucovorin

Three sublines of NIH 3T3 cells had the properties of non-neoplastic, preneoplastic, and neoplastic cells, respectively. The closer the cells were to neoplastic behavior, characterized by continuing growth at high density, the slower they multiplied at lower density. Under the conditions of high population density and low calf serum concentration used in the assay for transformed focus formation, the transformed or neoplastic cells were much more sensitive to killing by methotrexate (MTX) than were non-neoplastic cells in the same culture. This differential sensitivity of neoplastic cells was far more pronounced in molecular, cellular, and developmental biology medium 402 (MCDB 402) than in DMEM. It is associated with the presence in MCDB 402 of folinic acid, known clinically as leucovorin, which is a reduced form of the folic acid present in DMEM. Although leucovorin had been shown to selectively spare normal bone marrow and intestine in animals from the killing effect of MTX on tumor cells, we demonstrate the preferential killing of neoplastic over non-neoplastic cells of the same derivation. Neither neoplastic nor non-neoplastic cells were killed once they had stopped multiplying at their respective saturation densities. The development of the light foci characteristic of the preneoplastic cells was less sensitive to MTX than the formation of the dense foci produced by the fully neoplastic cells. The system should serve as a valuable model to establish basic principles and optimal conditions for selective killing of neoplastic cells by chemotherapeutic drugs.

Ubiquitous, heritable damage in cell populations that survive treatment with methotrexate

A permanent line of mouse embryo fibroblasts was treated with concentrations of the anticancer drug methotrexate (MTX) that left 20–50% surviving colonies. The surviving population initially multiplied at a much slower rate than controls after subculture in the absence of the drug, and required 9–12 days of serial subculture, with selective growth of the faster growing cells, to approximate the control rate. To determine the distribution of growth rates of cells in the original posttreatment populations, many single cells were isolated in multiwell plates immediately after the treatment period, and the resulting clones were serially subcultured. Most of the control clones underwent about 2 population doublings per day (PD/D). Almost all the survivors of MTX treatment multiplied at heterogeneously reduced rates, ranging from 0.6 PD/D to as high as control rates for a very few clones. They maintained the reduced rates through many subcultivations. The heritability of the reduced growth rates indicates that most cells that retain proliferative capacity after treatment with MTX carry random genetic damage that is perpetuated through many divisions of their progeny. Similar results have been described for cells that survive x-irradiation, and suggest random genetic damage is a common occurrence among cells in rapidly growing tissues that survive cytotoxic treatment. It also occurs in serial subcultures of cells that had been held under the constraint of confluence for extended periods, which suggests that the accumulation of random genetic damage to somatic cells during aging of mammals underlies the reduction of growth rate and function of the cells that characterizes the aging process.

DHFR/MSH3 amplification in methotrexate-resistant cells alters the hMutSα/hMutSβ ratio and reduces the efficiency of base–base mismatch repair

The level and fate of hMSH3 (human MutS homolog 3) were examined in the promyelocytic leukemia cell line HL-60 and its methotrexate-resistant derivative HL-60R, which is drug resistant by virtue of an amplification event that spans the dihydrofolate reductase (DHFR) and MSH3 genes. Nuclear extracts from HL-60 and HL-60R cells were subjected to an identical, rapid purification protocol that efficiently captures heterodimeric hMutSα (hMSH2⋅hMSH6) and hMutSβ (hMSH2⋅hMSH3). In HL-60 extracts the hMutSα to hMutSβ ratio is roughly 6:1, whereas in methotrexate-resistant HL-60R cells the ratio is less than 1:100, due to overproduction of hMSH3 and heterodimer formation of this protein with virtually all the nuclear hMSH2. This shift is associated with marked reduction in the efficiency of base–base mismatch and hypermutability at the hypoxanthine phosphoribosyltransferase (HPRT) locus. Purified hMutSα and hMutSβ display partial overlap in mismatch repair specificity: both participate in repair of a dinucleotide insertion–deletion heterology, but only hMutSα restores base–base mismatch repair to extracts of HL-60R cells or hMSH2-deficient LoVo colorectal tumor cells.