The incidence of venous thromboembolic events in trauma patients after tranexamic acid administration: an EAST multicenter study.

To determine if there is a significant association between administration of tranexamic acid (TXA) in severely bleeding, injured patients, and venous thromboembolism (VTE), myocardial infarction (MI), or cerebrovascular accident (CVA). A multicenter, retrospective study was performed. Inclusion criteria were: age 18-80 years old and need for 5 units or more of blood in the first 24 h after injury. Exclusion criteria included: death within 24 h, pregnancy, administration of TXA more than 3 h following injury, and routine ultrasound surveillance for deep venous thrombosis. Incidence of VTE was the primary outcome. Secondary outcomes included MI, CVA, and death. A power analysis found that a total of 830 patients were needed to detect a true difference in VTE risk. 1333 patients (TXA = 887, No-TXA = 446 patients) from 17 centers were enrolled. There were no differences in age, shock index, Glasgow coma score, pelvis/extremity abbreviated injury score, or paralysis. Injury severity score was higher in the No-TXA group. Incidence of VTE, MI, or CVA was similar between the groups. The TXA group required significantly less transfusion (P < 0.001 for all products) and had a lower mortality [adjusted odds ratio 0.67 (95% confidence interval 0.45-0.98)]. Despite having a higher extremity/pelvis abbreviated injury score, results did not change when evaluating only patients with blunt injury. Use of TXA in bleeding, injured patients is not associated with VTE, MI, or CVA but is associated with a lower transfusion need and mortality.

REFERENCE INTERVALS FOR PLASMA BIOCHEMISTRY OF HEMOLYMPH IN SUBADULT CHILEAN ROSE TARANTULA (GRAMMASTOLA ROSEA) UNDER CHEMICAL RESTRAINT.

Tarantulas are a commonly kept species that are occasionally presented to veterinarians in exotic practice. A recent study on Grammastola rosea hemolymph biochemistry has been performed with nonanesthetized adult theraphosids. The objective of this study was to produce reference intervals for biochemistry biomarkers in hemolymph of chemically restrained G. rosea for use diagnostically by exotic veterinarians. Cardiac hemolymph collection was performed on 20 subadult tarantulas under general anesthesia with isoflurane. Samples were processed by a commercial laboratory. Statistics performed on the data include outlier exclusion, descriptive statistics, normality tests, and Pearson correlations. Reference intervals were made for total protein, creatine kinase (CK), aspartate aminotransferase (AST), glucose, uric acid (UA), calcium, and phosphorus. No cortisol was detected. The majority of the intervals produced were normally distributed with the exceptions of UA, phosphorus, and CK. Pearson correlation tests found several significant (P = <0.05) correlations between variables. The majority of the data displayed a normal distribution, unlike the previous study, with a greater number of replicates. The total protein, glucose, UA, calcium, and AST values generated were similar to those reported in the previous study. Conversely several variables such as phosphorus, CK, and albumin were not consistent with those previously reported. Evidence is presented for a lack of albumin, CK, and AST in Arachnida and thus previous data for these proteins is likely to be artifactual.

Prevalence and breed predisposition for thoracolumbar intervertebral disc disease in cats.

Objectives The objective was to evaluate the prevalence and possible breed predilections for thoracolumbar intervertebral disc disease (IVDD) in cats. Methods Medical records and imaging studies of cats diagnosed with thoracolumbar IVDD between January 2008 and August 2014 were retrospectively reviewed and compared with the general hospital population. The association between type of IVDD (ie, intervertebral disc extrusion [IVDE] or intervertebral disc protrusion [IVDP]) and breed, age, sex, and duration and severity of clinical signs was also evaluated. Results Of 12,900 cats presented during the study period, 31 (0.24%) were diagnosed with IVDD, including 17 purebred and 14 non-purebred cats. Of all presented purebred cats, 0.52% were diagnosed with thoracolumbar IVDD. More specifically, 1.29% of all British Shorthairs and 1.83% of all presented Persians were diagnosed with IVDD. Compared with the general hospital population, purebred cats ( P = 0.0001), British Shorthairs ( P <0.0001) and Persians ( P = 0.0006) were significantly overrepresented with thoracolumbar IVDD. Affected purebred cats were younger than affected non-purebred cats ( P = 0.02). Of 31 cats with IVDD, 19 were diagnosed with IVDE and 12 with IVDP. Cats with IVDE had a significantly shorter duration of clinical signs ( P = 0.0002) and demonstrated more severe neurological deficits ( P = 0.04) than cats with IVDP. Conclusions and relevance Although thoracolumbar IVDD is an uncommon condition in cats, purebred cats, British Shorthairs and Persians, were overrepresented. It is currently unclear if this represents a true breed predisposition or a higher likelihood of owners of purebred cats seeking referral for advanced diagnostic imaging procedures.

Development of a purity control strategy for pemetrexed disodium and validation of associated analytical methodology.

Stability-indicating reversed phase HPLC methods have been developed and validated for the determination of 13 potential process and degradation impurities in pemetrexed disodium drug substance (DS) and pemetrexed for injection drug product (DP). This paper describes the development of HPLC-UV impurity methods for drug substance and drug product. Relative response factors (RRF) have been determined using HPLC-UV in tandem with CAD or by NMR detection. Conditions for the generation of system suitability solutions are described and assure adequate chromatographic resolution and peak identification without the need for impurity reference standards. The methods were fully validated and demonstrated to have acceptable specificity, linearity, accuracy, repeatability, intermediate precision, detection/quantitation limit, and robustness.

Importance of Connexin-43 based gap junction in cirrhosis and acute-on-chronic liver failure.

BACKGROUND & AIMS: In cirrhosis, superimposed inflammation often culminates in acute-on-chronic liver failure (ACLF) but the mechanism underlying this increased sensitivity is not clear. Cx43 is a ubiquitous gap junction protein that allows transmission of signals between cells at a much higher rate than the constitutively expressed gap junctions. The aims of the study were to test the hypothesis that inflammation drives the increased expression of hepatic Cx43 and to determine its role by Cx43 inhibition. METHODS: Four weeks after bile-duct ligation (BDL) or sham operation, rats were treated with an anti-TNF antibody, or saline; with or without LPS (1mg/kg); given 3h prior to termination. Biochemistry and cytokines were measured in the plasma and hepatic protein expression (NFkB, TNFα, iNOS, 4HNE, Cx26, 32, and 43) and confocal microscopy (Cx26, 32, and 43) were performed. The effect of a Cx43-specific inhibitory peptide was studied in a mouse BDL model. RESULTS: BDL animals administered LPS developed typical features of ACLF but animals administered infliximab were relatively protected. Cx26/32 expression was significantly decreased in BDL animals while Cx43 was significantly increased and increased further following LPS. Infliximab treatment prevented this increase. However, inhibiting Cx43 in BDL mice produced detrimental effects with markedly greater hepatocellular necrosis. CONCLUSIONS: The results of this study show for the first time an increased expression of hepatic Cx43 in cirrhosis and ACLF, which was related to the severity of inflammation. This increased Cx43 expression is likely to be an adaptive protective response of the liver to allow better cell-to-cell communication.

Oriental cholangiohepatitis masquerading as cholangiocarcinoma: A rare presentation that surgeons need to know.

INTRODUCTION: The detection of an abnormal hepatic mass with ductal dilatation is highly concerning for malignancy. However, if such patients happen to be immigrants from endemic parts of Asia or South America, further investigations are necessary to rule out oriental cholangiohepatitis, a rare recurrent disease of the hepatobiliary system that can masquerade as cholangiocarcinoma. PRESENTATION OF CASE: We report a case of a patient of South Asian origin who presented to us with acute cholangitis and moderately dilated left hepatic ducts. The findings were highly suspicious for advanced hepatic malignancy; however the laboratory and pathological investigations remained normal. We suspected an unlikely etiology and proceeded with conservative hepatic resection. The histology revealed cholangiohepatitis without any evidence of malignancy. DISCUSSION: Cholangiohepatitis is a complex hepatobiliary disease that commonly manifests as recurrent cholangitis or overt biliary sepsis and can rarely present as an abnormal hepatic mass. It results from the development of intrahepatic or extrahepatic strictures that causes stone formation and biliary dilation in the absence of gallbladder disease. Although it is endemic in many parts of the world, it is rare in the western world, and therefore it can present as a significant diagnostic enigma. CONCLUSION: Cholangiohepatitis is a rare clinical entity that requires a multi-disciplinary team approach. Surgery plays a dominant role in the management of such patients and therefore surgeons need to be aware of this disease.

Development and validation of non-aqueous capillary electrophoresis methods to analyze boronic esters and acids.

Boronic esters and acids are potential intermediates in the manufacture of many active pharmaceutical ingredients (API). Accurate quantitation of the intermediate is necessary to assure the stoichiometry of the reaction. The analysis of these compounds is challenging due to their labile nature. For example, the boronic ester can hydrolyze to the acid during storage, when exposed to moisture in the air, during sample preparation and analysis, and thus give erroneous ester results. Traditional analytical techniques like gas chromatography (GC), normal phase chromatography (NPLC), hydrophilic interaction chromatography (HILIC), and reversed phase liquid chromatography (RPLC) have been utilized but with noted limitations such as poor peak shape, variation in retention times, and evidence of hydrolysis. All of these limitations impact accurate quantitation needed for selected situations. For the proprietary boronic ester evaluated here, these traditional techniques were insufficient for the accurate determination of assay and residual boronic acid. Non-aqueous capillary electrophoresis (NACE) is an accurate quantitative technique that can be used to analyze boronic esters and their corresponding acids without the limitations noted for traditional analytical techniques. The present study describes the development of methodology for the determination of the potency of a proprietary boronic ester as well as methodology for the determination of residual boronic acid in the ester. In addition, nine model boronic ester and acid pairs with a range in polarity, based on the electronic properties of the attached side group, were tested to evaluate and demonstrate the general applicability of these conditions. Under the conditions used for potency, all ten pairs had a resolution between the boronic ester and acid of greater than 1.5, acceptable peak shape for the boronic ester (tailing factor of less than 2.0), and a run time of less than 3 min. In addition, this work describes the development of methodology to determine residual levels of boronic acids in the corresponding boronic ester. Using the ten boronic ester and acid pairs, eight of the ten pairs were shown to have acceptable sensitivity (S/N of 10 or better at 0.5%) and spike recoveries (within the range of 80-120%). The potential for hydrolysis during analysis was also addressed by using a subset of the ten boronic ester and acid pairs and spiking water into the diluent. There was no observed conversion of the ester to the acid. The lack of hydrolysis during analysis and the high success in separating and validating these methods for the boronic ester and acid pairs supports the utility of NACE as a technique for the analysis of boronic esters and acids.

S-Adenosylmethionine regulates connexins sub-types expressed by hepatocytes.

Intercellular communication via GAP Junctions plays an important role in tissue homeostasis, apoptosis, carcinogenesis, cell proliferation and differentiation. Hepatocyte connexins (Cx) 26 and 32 levels are decreased during the de-differentiation process of primary hepatocytes in culture, a situation that is also characterized by a decrease in S-Adenosylmethionine (SAMe) levels. In this current study, we show that SAMe supplementation in cultured hepatocytes every 12h, leads to an up-regulation of Cx26 and 32 mRNA and protein levels and blocks culture-induced Cx43 expression, although it failed to increase Cx26 and 32 membrane localization and GAP junction intracellular communication. SAMe reduced nuclear ß-catenin accumulation, which is known to stimulate the TCF/LEF-dependent gene transcription of Cx43. Moreover SAMe-induced reduction in Cx43 and ß-catenin was prevented by the proteasome inhibitor MG132, and was not mediated by GSK3 activity. SAMe, and its metabolite 5'-methylthioadenosine (MTA) increased Cx26 mRNA in a process partially mediated by Adenosine A(2A) receptors but independent of PKA. Finally livers from MAT1A knockout mice, characterized by low hepatic SAMe levels, express higher Cx43 and lower Cx26 and 32 protein levels than control mice. These results suggest that SAMe maintains a characteristic expression pattern of the different Cxs in hepatocytes by differentially regulating their levels.

Development of pyrF-based genetic system for targeted gene deletion in Clostridium thermocellum and creation of a pta mutant.

We report development of a genetic system for making targeted gene knockouts in Clostridium thermocellum, a thermophilic anaerobic bacterium that rapidly solubilizes cellulose. A toxic uracil analog, 5-fluoroorotic acid (5-FOA), was used to select for deletion of the pyrF gene. The ΔpyrF strain is a uracil auxotroph that could be restored to a prototroph via ectopic expression of pyrF from a plasmid, providing a positive genetic selection. Furthermore, 5-FOA was used to select against plasmid-expressed pyrF, creating a negative selection for plasmid loss. This technology was used to delete a gene involved in organic acid production, namely pta, which encodes the enzyme phosphotransacetylase. The C. thermocellum Δpta strain did not produce acetate. These results are the first examples of targeted homologous recombination and metabolic engineering in C. thermocellum, a microbe that holds an exciting and promising future in the biofuel industry and development of sustainable energy resources.

Manipulations of PKA in chick limb development reveal roles in digit patterning including a positive role in Sonic Hedgehog signaling.

Sonic Hedgehog (Shh) signaling by the polarizing region, at the posterior of the vertebrate limb bud, is pivotal in determining digit number and identity. Shh establishes a gradient of the bifunctional transcriptional effector, Gli3, with high levels of full-length activator (Gli3A) in the posterior bud, where digits form, and high levels of shorter repressor (Gli3R) in the anterior. Repressor formation depends on protein kinase A (PKA), but in Drosophila, PKA also plays a role in activator function. Increasing PKA levels in chick limb development using Forskolin had no effect on posterior polarizing activity but weak polarizing activity, based on ligand-independent Shh signaling, was induced in anterior limb bud cells resulting in extra digits. Manipulating PKA activity levels directly with a retrovirus expressing activated PKA induced extra digits similar to those induced by Forskolin treatment suggesting that PKA may have a previously unrecognized positive role in Shh signaling in vertebrate limbs. Expressing dominant negative PKA also induced extra, sometimes multiple digits, from anterior limb bud demonstrating the negative role in Shh signaling. PKA levels in the limb bud are high posteriorly and low anteriorly, suggesting that PKA activity may influence the outcome of Shh signaling in normal development.

Assessing adherence to evidence-based guidelines for the diagnosis and management of uncomplicated urinary tract infection.

OBJECTIVE: To assess adherence to evidence-based guidelines for the diagnosis and management of uncomplicated urinary tract infection (UTI) in a family medicine residency clinic setting. PATIENTS AND METHODS: We retrospectively reviewed the medical records of female patients seen in 2005 at the Mayo Clinic Family Medicine Center in Scottsdale, Ariz, who were identified by International Classification of Diseases, Ninth Revision code 599.0 (UTI). We assessed documentation rates, use of diagnostic studies, and antibiotic treatments. Antibiotic sensitivity patterns from outpatient urine culture and sensitivity analyses were determined. RESULTS: Of 228 patients, 68 (30%) had uncomplicated UTI. Our physicians recorded essential history and examination findings for most patients. Documentation of the risk of sexually transmitted disease differed between residents and attending physicians and was affected by patient age. Urine dipstick and urine culture and sensitivity analyses were ordered in 57 (84%) and 52 (76%) patients, respectively. Eighty percent of patients with positive results on urine dipstick analyses also had urine culture and sensitivity analyses. Sulfamethoxazole-trimethoprim (SMX-TMP) was used as initial therapy in 26 patients (38%). Sixty-one percent of SMX-TMP and ciprofloxacin prescriptions were appropriately provided for 3 days. Escherichia coil was sensitive to SMX-TMP in 33 (94%) of 35 cultures. Treatment was not changed in any patient with an uncomplicated UTI because of results of urine culture and sensitivity analyses. Antibiotic sensitivity patterns for outpatients were significantly different from those for inpatients. CONCLUSION: Only 30% of our patients had uncomplicated UTI, making their management within clinical guidelines appropriate. However, of those patients with uncomplicated UTI, less than 25% received empirical treatment as suggested. Urine culture and sensitivity analyses were performed frequently, even in patients who already had positive results on a urine dip-stick analysis. Although SMX-TMP is effective, it is underused. On the basis of these findings, we hope to provide interventions to increase SMX-TMP prescription, decrease use of urine culture and sensitivity analyses, and increase the frequency of 3-day antibiotic treatments at our institution.

Simplification and its consequences in biological modelling: conclusions from a study of calcium oscillations in hepatocytes.

Systems Biology requires that biological modelling is scaled up from small components to system level. This can produce exceedingly complex models, which obscure understanding rather than facilitate it. The successful use of highly simplified models would resolve many of the current problems faced in Systems Biology. This paper questions whether the conclusions of simple mathematical models of biological systems are trustworthy. The simplification of a specific model of calcium oscillations in hepatocytes is examined in detail, and the conclusions drawn from this scrutiny generalized. We formalize our choice of simplification approach through the use of functional 'building blocks'. A collection of models is constructed, each a progressively more simplified version of a well-understood model. The limiting model is a piecewise linear model that can be solved analytically. We find that, as expected, in many cases the simpler models produce incorrect results. However, when we make a sensitivity analysis, examining which aspects of the behaviour of the system are controlled by which parameters, the conclusions of the simple model often agree with those of the richer model. The hypothesis that the simplified model retains no information about the real sensitivities of the unsimplified model can be very strongly ruled out by treating the simplification process as a pseudo-random perturbation on the true sensitivity data. We conclude that sensitivity analysis is, therefore, of great importance to the analysis of simple mathematical models in biology. Our comparisons reveal which results of the sensitivity analysis regarding calcium oscillations in hepatocytes are robust to the simplifications necessarily involved in mathematical modelling. For example, we find that if a treatment is observed to strongly decrease the period of the oscillations while increasing the proportion of the cycle during which cellular calcium concentrations are rising, without affecting the inter-spike or maximum calcium concentrations, then it is likely that the treatment is acting on the plasma membrane calcium pump.

Annular rash on a newborn.

A full-term, healthy female newborn was delivered via cesarean section because the labor did not adequately progress. The mother, age 33 years and of Asian ancestry, had a significant medical and obstetrical history: chronic hepatitis B carrier without cirrhosis, cutaneous lupus erythematosus (positive anti-Ro and anti-La antibodies), and a positive group B streptococcal recto-vaginal culture at 35 weeks' gestation. The mother received 4 doses of intravenous ampicillin during labor. The infant's initial hospital course was complicated by a transient and otherwise asymptomatic bradycardia. An electrocardiogram (ECG) confirmed a heart rate of 96 with normal interval parameters, but there were changes suggestive of left ventricular hypertrophy. An echocardiogram was normal. Follow-up office visits for common newborn feeding problems demonstrated consistent weight gain and normal vital signs, including heart rate and facial milia. However, by age 4 weeks an erythematous eruption extending from the frontal scalp and forehead to the cheek area had developed. What is the differential diagnosis? What tests should be done to make the diagnosis?

Dynamics of membrane clathrin-coated structures during cytokinesis.

Remodeling of cell membranes takes place during motile processes such as cell migration and cell division. Defects of proteins involved in membrane dynamics, including clathrin and dynamin, disrupt cytokinesis. To understand the function of clathrin-containing structures (CCS) in cytokinesis, we have expressed a green fluorescent protein (GFP) fusion protein of clathrin light chain a (GFP-clathrin) in NRK epithelial cells and recorded images of dividing cells near the ventral surface with a spinning disk confocal microscope. Punctate GFP-CCS underwent dynamic appearance and disappearance throughout the ventral surface. Following anaphase onset, GFP-CCS between separated chromosomes migrated toward the equator and subsequently disappeared in the equatorial region. Movements outside separating chromosomes were mostly random, similar to what was observed in interphase cells. Directional movements toward the furrow were dependent on both actin filaments and microtubules, while the appearance/disappearance of CCS was dependent on actin filaments but not on microtubules. These results suggest that CCS are involved in remodeling the plasma membrane along the equator during cytokinesis. Clathrin-containing structures may also play a role in transporting signaling or structural components into the cleavage furrow.