Hollow viscus perforation in blunt abdominal trauma: A 14-year experience from a trauma center

BACKGROUND

Isolated perforations of hollow viscus (HV) represent less than 1% of injuries in blunt abdominal trauma (BAT). When they do present, they are generally due to high-impact mechanisms in the segments of the intestine that are fixed. The aim of this study is to determine the incidence of major HV injuries in BAT at the "Dr. Domingo Luciani" General Hospital (HDL), and address the literature gap regarding updated HV perforations following BAT, especially in low-income settings.

METHODS

A retrospective review was conducted on the medical records of patients admitted to our trauma center with a diagnosis of complicated BAT with HV perforation over 14 years.

RESULTS AND DISCUSSION

Seven hundred sixty-one patients were admitted under the diagnosis of BAT. Of them, 36.79% underwent emergency surgical resolution, and 6.04% had HV perforation as an operative finding. Almost half (44.44%) of these cases presented as a single isolated injury, while the remaining were associated with other intra-abdominal organ injuries. The most common lesions were Grade II-III jejunum and Grade I transverse colon, affecting an equal proportion of patients at 13.33%. In recent years, an increased incidence of HV injuries secondary to BAT has been observed. Despite this, in many cases, the diagnosis is delayed, so even in the presence of negative diagnostic studies, the surgical approach based on the trauma mechanism, hemodynamic status, and systematic reevaluation of the polytraumatized patient should prevail.

Phase I study of peposertib and avelumab with or without palliative radiotherapy in patients with advanced solid tumors

INTRODUCTION

We report results from a phase I, three-part, dose-escalation study of peposertib, a DNA-dependent protein kinase inhibitor, in combination with avelumab, an immune checkpoint inhibitor, with or without radiotherapy in patients with advanced solid tumors.

MATERIALS AND METHODS

Peposertib 100-400 mg twice daily (b.i.d.) or 100-250 mg once daily (q.d.) was administered in combination with avelumab 800 mg every 2 weeks in Part A or avelumab plus radiotherapy (3 Gy/fraction × 10 days) in Part B. Part FE assessed the effect of food on the pharmacokinetics of peposertib plus avelumab. The primary endpoint in Parts A and B was dose-limiting toxicity (DLT). Secondary endpoints were safety, best overall response per RECIST version 1.1, and pharmacokinetics. The recommended phase II dose (RP2D) and maximum tolerated dose (MTD) were determined in Parts A and B.

RESULTS

In Part A, peposertib doses administered were 100 mg (n = 4), 200 mg (n = 11), 250 mg (n = 4), 300 mg (n = 6), and 400 mg (n = 4) b.i.d. Of DLT-evaluable patients, one each had DLT at the 250-mg and 300-mg dose levels and three had DLT at the 400-mg b.i.d. dose level. In Part B, peposertib doses administered were 100 mg (n = 3), 150 mg (n = 3), 200 mg (n = 4), and 250 mg (n = 9) q.d.; no DLT was reported in evaluable patients. Peposertib 200 mg b.i.d. plus avelumab and peposertib 250 mg q.d. plus avelumab and radiotherapy were declared as the RP2D/MTD. No objective responses were observed in Part A or B; one patient had a partial response in Part FE. Peposertib exposure was generally dose proportional.

CONCLUSIONS

Peposertib doses up to 200 mg b.i.d. in combination with avelumab and up to 250 mg q.d. in combination with avelumab and radiotherapy were tolerable in patients with advanced solid tumors; however, antitumor activity was limited.

CLINICALTRIALS

GOV IDENTIFIER

NCT03724890.

Comparison of wheelchair securement systems designed for use in large accessible transit vehicles (LATVs)

Design challenges in wheelchair securement for fixed-route, large accessible transit vehicles (LATVs) often create difficulties for passengers who use wheelchairs and operational inefficiencies for public transit agencies. Recent innovations in wheelchair securement technology for LATVs may reduce these challenges. This study explored the usability of three commercially available wheelchair securement systems in a static laboratory environment: a four-point, forward-facing (4P-FF) securement system, a three-point, forward-facing (3P-FF) securement system, and a semi-automated, rear-facing (SA-RF) securement system. Three groups of mobility device users (manual wheelchair users, power wheelchair users, and scooter users) (n = 36) completed wheelchair securement tasks in a full-scale mock-up of an LATV. For the 19 participants who did not use the occupant restraint system (ORS), perceived usability and securement time were compared across the securement systems. Using multiple usability rating scales, most participants reported that each of the systems would be acceptable for regular use. However, the majority indicated an overall preference for the SA-RF, and most rated the SA-RF system as easier, faster, and requiring less assistance to use than the 4P-FF and 3P-FF systems. Alternatives to conventional 4P-FF wheelchair securement in LATVs may thus improve boarding efficiency and transit independence of passengers who use wheelchairs.

Capillary malformation-arteriovenous malformation syndrome: a multicentre study

BACKGROUND

Capillary malformation-arteriovenous malformation (CM-AVM) syndrome is a rare syndrome with characteristic skin lesions that are associated with fast-flow vascular malformations (FFVMs) in one-third of patients. Few case series have been described, and none in Spain.

AIM

To identify the prevalence of dermatological parameters, FFVMs and associated features in a large series of patients with CM-AVM.

METHODS

We conducted an observational study of patients with CM-AVM syndrome diagnosed in 15 Spanish hospitals over 3 years. The main clinical, radiological, genetic findings and associated diseases were analysed.

RESULTS

In total, 64 patients were assessed. In 26.5% of cases, the diagnosis was incidental. In 75% of patients, there was one significantly larger macule, which we termed the 'herald patch'. FFVMs were detected in 34% of the patients, with 30% located on the skin, 7.8% in the brain and in 1.5% in the spine. There was a positive family history in 65% of the 64 patients. Genetic analysis was performed for RASA1 mutations in 57 patients, of whom 42 (73%) had a positive result. All 4 patients tested for EPHB4 mutations had a positive result. No tumour lesions were detected in the series, except for five infantile haemangiomas.

CONCLUSIONS

Our data on clinical lesions, associated FFVM, family history and genetics are similar to those previously published in the literature. An extensive data analysis failed to demonstrate any statistically significant association between the presence of an FFVM and any clinical, familial or genetic parameter that could predict its onset, although a link between the presence of a herald patch on the midline face and the presence of a brain FFVM was observed. We did not detect any genotype-phenotype correlation.

[Novel treatments in neurometabolic diseases: the importance of chaperones]

Incorrect protein folding has been related to a number of genetic diseases. In these pathologies, loss and gain of function mutations can cause protein instability, giving rise to alterations in their catalytic properties or in their subcellular location. The literature includes reports of a number of diseases, called conformational diseases, which are produced by mutations that affect folding. Therefore, many pathologies could benefit from treatment with certain drugs such as proteostasis regulators or pharmacologic chaperones. This work describes the potential use of pharmacologic chaperones in several neurometabolic diseases, specifically, in phenylketonuria, in phosphomannomutase deficit and in methylmalonic aciduria type cblB.

THE CHALLENGE OF CIEMAT INTERNAL DOSIMETRY SERVICE FOR ACCREDITATION ACCORDING TO ISO/IEC 17025 STANDARD, FOR IN VIVO AND IN VITRO MONITORING AND DOSE ASSESSMENT OF INTERNAL EXPOSURES

The accreditation of an Internal Dosimetry Service (IDS) according to ISO/IEC 17025 Standard is a challenge. The aim of this process is to guarantee the technical competence for the monitoring of radionuclides incorporated in the body and for the evaluation of the associated committed effective dose E(50). This publication describes the main accreditation issues addressed by CIEMAT IDS regarding all the procedures involving good practice in internal dosimetry, focussing in the difficulties to ensure the traceability in the whole process, the appropriate calculation of detection limit of measurement techniques, the validation of methods (monitoring and dose assessments), the description of all the uncertainty sources and the interpretation of monitoring data to evaluate the intake and the committed effective dose.

Paraspinal muscle volume in patients with Scheuermann's Kyphosis

To measure the cross-sectional area (CSA) of para-spinal muscles in Scheuermann's kyphosis patients. Preoperative MRI images of 16 Scheuermann's kyphosis patients were analysed and compared to 16 patients with normal MRI images (control group). The CSAs were measured at L3-4 and L4-5. Both groups showed similar demographics and patient characteristics. The multifidus muscles CSA were found to be significantly smaller at L3/4 level in Scheuermann's kyphosis patients (p = 0.022 on the left and p = 0.016 on the right side compared to control group). There was no significant change in multifidus CSA found at L4/5. The mean CSA of the extensor spinae muscles group were significantly smaller at all levels in Scheuermann's kyphosis patients : p = 0.001 bilaterally at L3/4 and p = 0.015 right side and p = 0.009 left side at L4/5 level. This study shows that patients with Scheuermann's kyphosis deformity have significantly smaller CSA of lumbar multifidus and extensor spinae muscles.

Molecular and phenotypic characteristics of seven novel mutations causing branched-chain organic acidurias

Specific mitochondrial enzymatic deficiencies in the catabolism of branched-chain amino acids cause methylmalonic aciduria (MMA), propionic acidemia (PA) and maple syrup urine disease (MSUD). Disease-causing mutations were identified in nine unrelated branched-chain organic acidurias (BCOA) patients. We detected eight previously described mutations: p.Asn219Tyr, p.Arg369His p.Val553Glyfs*17 in MUT, p.Thr198Serfs*6 in MMAA, p.Ile144_Leu181del in PCCB, p.Gly288Valfs*11, p.Tyr438Asn in BCKDHA and p.Ala137Val in BCKDHB gene. Interestingly, we identified seven novel genetic variants: p.Leu549Pro, p.Glu564*, p.Leu641Pro in MUT, p.Tyr206Cys in PCCB, p.His194Arg, p.Val298Met in BCKDHA and p.Glu286_Met290del in BCKDHB gene. In silico and/or eukaryotic expression studies confirmed pathogenic effect of all novel genetic variants. Aberrant enzymes p.Leu549Pro MUT, p.Leu641Pro MUT and p.Tyr206Cys PCCB did not show residual activity in activity assays. In addition, activity of MUT enzymes was not rescued in the presence of vitamin B12 precursor in vitro which was in accordance with non-responsiveness or partial responsiveness of patients to vitamin B12 therapy. Our study brings the first molecular genetic data and detailed phenotypic characteristics for MMA, PA and MSUD patients for Serbia and the whole South-Eastern European region. Therefore, our study contributes to the better understanding of molecular landscape of BCOA in Europe and to general knowledge on genotype-phenotype correlation for these rare diseases.

Tamoxifen as a new therapeutic tool for neutrophilic lung inflammation

BACKGROUND AND OBJECTIVE

Neutrophilic asthma is an important disease subgroup, including patients with severe phenotypes and erratic responses to standard treatments. Tamoxifen (TX), a selective estrogen receptor modulator (SERM) used as treatment of human breast cancer, has been shown to induce early apoptosis of equine blood and bronchoalveolar lavage fluid (BALF) neutrophils in vitro. Equine recurrent airway obstruction (RAO) is a naturally occurring neutrophilic condition, closely related with human asthma. Our purpose was to investigate the therapeutic potential of tamoxifen in horses with neutrophilic lung inflammation.

METHODS

Twelve horses underwent acute lung inflammation through exposure to allergens known to cause RAO, after which they received treatment with either tamoxifen or dexamethasone. Outcome measures included evaluation of clinical signs, BALF cytology, and early apoptosis of blood and BALF neutrophils.

RESULTS

Tamoxifen treatment decreased BALF neutrophil counts (65.3 ± 19.38% before treatment; 7.6 ± 4.5% 2 days post-treatment,; and 13.6 ± 9.3% 5 days post-treatment). A similar decrease was observed with dexamethasone treatment (48.6 ± 5.88% before treatment; 11.5 ± 8.1% 2 days post-treatment; 14.6 ± 10.3% 5 days post-treatment). Clinical and endoscopic scores improved in both treatment groups. Tamoxifen treatment significantly increased early apoptosis of peripheral blood neutrophils at 5 days post-treatment (27.04 ± 15.2%), and in BALF neutrophils at 2 and 5 days post-treatment (42.11 ± 11.67% and 48.98 ± 2.6%, respectively).

CONCLUSION

Tamoxifen treatment in horses with induced acute pulmonary inflammation promoted early apoptosis of blood and BALF neutrophils, reduction in BALF neutrophils and improvement in the animals' clinical status.

Current status of prenatal diagnosis in Cuba: causes of low prevalence of Down syndrome

OBJECTIVES

To analyze trends in cytogenetic prenatal diagnosis in Cuba and to analyze possible causes leading to a low Down syndrome prevalence in a country where the triple test is not available.

METHODS

An analysis of the Cuban program in prenatal cytogenetic diagnosis from 1984 to 2012 was conducted. Results are described, with particular emphasis on indications, abnormal results, types of invasive procedures, and terminations of pregnancy.

RESULTS

Cytogenetic prenatal diagnostic analyses (n = 75,095) were conducted; maternal age was the indication for 77.9% of the amniocenteses and chorionic villus samplings. The detection rate of chromosomally abnormal pregnancies was 2.3% for maternal age and increased to 8-9% for other indications. When a chromosomal abnormality was identified, 88.5% terminated the pregnancy. In 2002, the live birth prevalence of Down syndrome was 8.4 per 10,000 live births, and in 2012, 7 per 10,000.

CONCLUSION

Prenatal diagnosis in Cuba has contributed to a significant reduction in chromosomal aberrations. The impact increased because of the demographic trends of the population, the high index of terminations of pregnancy, and the establishment of a network of cytogenetic laboratories throughout Cuba.

"Very early" intrahepatic cholangiocarcinoma in cirrhotic patients: should liver transplantation be reconsidered in these patients?

A retrospective cohort multicenter study was conducted to analyze the risk factors for tumor recurrence after liver transplantation (LT) in cirrhotic patients found to have an intrahepatic cholangiocarcinoma (iCCA) on pathology examination. We also aimed to ascertain whether there existed a subgroup of patients with single tumors ≤2 cm ("very early") in which results after LT can be acceptable. Twenty-nine patients comprised the study group, eight of whom had a "very early" iCCA (four of them incidentals). The risk of tumor recurrence was significantly associated with larger tumor size as well as larger tumor volume, microscopic vascular invasion and poor degree of differentiation. None of the patients in the "very early" iCCA subgroup presented tumor recurrence compared to 36.4% of those with single tumors >2 cm or multinodular tumors, p = 0.02. The 1-, 3- and 5-year actuarial survival of those in the "very early" iCCA subgroup was 100%, 73% and 73%, respectively. The present is the first multicenter attempt to ascertain the risk factors for tumor recurrence in cirrhotic patients found to have an iCCA on pathology examination. Cirrhotic patients with iCCA ≤2 cm achieved excellent 5-year survival, and validation of these findings by other groups may change the current exclusion of such patients from transplant programs.

Apoptotic effects of tamoxifen on leukocytes from horse peripheral blood and bronchoalveolar lavage fluid

A reduction in inflammatory cell apoptosis is an important concept in the maintenance of inflammation and a potential target for the resolution of inflammation in many inflammatory diseases. Dysregulation of apoptosis has been implicated in a range of diseases, including tumors, neurodegenerative disorders and autoimmunity, and may also be implicated in allergic asthma. In horses, recurrent airway obstruction (RAO) is an asthma-like condition that is characterized increased survival neutrophil bronchial. Tamoxifen is a synthetic, non-steroidal, anti-estrogen agent that is widely used for treating all stages of breast cancer and has been approved for the prevention of breast cancer in high-risk women. The observed efficacy of tamoxifen has been attributed to both growth arrest and the induction of apoptosis. Therefore, the aim of our study was to evaluate the ability of tamoxifen to induce apoptosis in vitro in granulocytic cells from peripheral blood and in mononuclear cells from bronchoalveolar lavage fluid (BALF) in horses. Flow cytometry using commercial AnnexinV-FITC and propidium iodide was used to quantify early and late apoptotic leukocytes, respectively. The results showed a significant increase in early apoptosis in peripheral blood and bronchial granulocytic cells treated with tamoxifen. The rate of early apoptosis of mononuclear cells from blood and BALF when incubated with tamoxifen was significantly lower compared with granulocytic cells. We did not observe a direct effect of tamoxifen on late apoptosis in any of the in vitro assays in the cell types used here. These results indicate that the apoptotic mechanisms under these experimental conditions would affect only blood and BALF granulocytic cells, particularly in early apoptosis. Finally, further in vitro and in vivo studies are needed to better understand apoptotic mechanisms because tamoxifen could be used to treat chronic, inflammatory pathologies associated with granulocytes and allergic diseases, such as asthma or equine RAO.

p∆TubHA4C, a new versatile vector for constitutive expression in Drosophila

Several vectors for gene expression are available in Drosophila, a hub for genetics and genomics innovation. However, the vectors for ubiquitous expression have a complex structure, including coding exons, that makes in-frame cloning of cDNAs very complicated. In this report we describe a new Drosophila expression vector (p∆TubHA4C) for ubiquitous expression of coding sequences under the control of a minimal 0.9 kb promoter of α1 tubulin (α1t). This plasmid was designed to include optimized multiple cloning sites (polylinker) to provide flexibility in cloning strategies. We also added the option of double labeling the expressed proteins with two C-terminal tags, the viral epitope hemagglutinin and a synthetic tetracysteine (4C) tag that binds small fluorescent compounds. This dual tag allows both in situ and biochemical detection of the desired protein. In particular, the new 4C tag technology combines easy fluorescent labeling with small arsenical compounds in live or fixed cells and tissues, while producing minimal alterations to the tagged protein due to its small size. To demonstrate the potent and ubiquitous expression under the control of the ∆Tub promoter, bacterial lacZ was expressed and monitored in cell culture and transgenic flies. We found that the modified 0.9 kb ΔTub promoter induced similar expression levels to the intact 2.6 kb α1t promoter, supporting the inclusion of all critical regulatory elements in the new and flexible ∆TubHA4C vector.

Electrical Characteristics of Chemical Solution Deposited Nd3+ Doped PZT (53/47) Thin Films in Planar Electrode Configuration

Electrical characteristics of ferroelectric thin films in planar electrode configuration are important to characterize these materials for their applications in micro electro mechanical (MEM) and tunable microwave devices. In the present work we have prepared polycrystalline Pb1划3x/2Ndx(Zr0.53Ti0.47)O3 (x = 0.0 to 10.0 at %) thin films on platinized silicon substrate by chemical solution deposition (CSD) technique. The films were characterized in terms of their dielectric and ferroelectric properties by depositing planar interdigital finger electrodes on the surface of the films by electron beam lithography. The capacitance and loss tangent of undoped and 4 at % Nd doped PZT films measured at 100 kHz were found to be 138 pF, 0.033 and 95 pF, 0.019 respectively. Saturated hysteresis loops were obtained in undoped PZT film by applying 100 V across 10 μm electrode separation. Nd doped PZT films on the other hand, electrically shorted at comparatively lower voltage. The electrical characteristics of these films are correlated with their phase formation behavior and microstructural features.

Validation of the FACT-Gastric cancer quality of life questionnaire for use in Spanish-speaking countries

OBJECTIVES

The purpose of this study was to validate a universal Spanish translation of the Functional Assessment of Cancer Therapy-Gastric Cancer (FACT-Ga; Version 4) questionnaire for use in Spanish-speaking countries.

METHODS

Translation of the FACT-Ga from English to Spanish was accomplished by employing the Functional Assessment of Chronic Illness Therapy (FACIT) translation methodology, which utilizes a multinational team of translation experts. A single (universal) Spanish version of the questionnaire was developed for use with gastric cancer patients recruited from Argentina, Chile, Mexico, Peru, and Spain. Pretesting of the questionnaire was conducted using 75 cancer patients (15 from each country), who were also cognitively debriefed.

RESULTS

Statistical analysis yielded marginal results for the Peru and Spain samples, although when analyzing pooled data from all five countries, statistics were within expected ranges. Qualitative analysis indicated that there were negligible linguistic concerns that impacted a very small proportion of the items.

CONCLUSION

The universal Spanish FACT-Ga demonstrates content and linguistic validity, and is conceptually equivalent to its English source. It is a promising tool for use in evaluating the health-related quality of life for Spanish-speaking patients with gastrointestinal-related cancers, given more research regarding universally derived reliability and validity statistics.

EURADOS intercomparison on measurements and Monte Carlo modelling for the assessment of americium in a USTUR leg phantom

A collaboration of the EURADOS working group on 'Internal Dosimetry' and the United States Transuranium and Uranium Registries (USTUR) has taken place to carry out an intercomparison on measurements and Monte Carlo modelling determining americium deposited in the bone of a USTUR leg phantom. Preliminary results and conclusions of this intercomparison exercise are presented here.

Living donor liver transplantation: usefulness of hemostatic and prothrombotic screening in potential donors

Bleeding and thrombosis are serious complications of living donor liver transplantation (LDLT). The aim of this paper was to describe the results of a screening for coagulation disorders, including for thrombophilic factors, in potential living liver graft donors and to evaluate thrombotic and bleeding events in donors and recipients, during and after the procedure. From January 2001 to January 2007, 41 LDLTs were performed at our institution. We performed systematic screening for bleeding or prothrombotic states among 188 potential donors, 38 (20.2%) of whom showed at least one abnormality. We rejected potential donors with factor V Leiden, prothrombin mutation G20210A, and deficiencies in anticoagulant proteins (protein C, protein S, and antithrombin) or coagulation factors. Bleeding and thrombotic events in donors and recipients of the 41 LDLTs were evaluated during 7 days to 70 months follow-up. No major bleeding events were detected in the donors. Neither donor nor recipient experienced venous thrombosis or pulmonary embolism. Among all recipients, six suffered hepatic artery thrombosis including five in the first month probably related to surgery. Deep venous thrombosis and pulmonary embolism are well-known complications of hepatic surgery; Prothrombotic abnormalities in the donor can be transmitted to the recipient, leading to increased risk of serious postoperative events. Although the cost-effectiveness is not definitely established, we recommend systematic screening for hemostatic and prothrombotic disorders to prevent more morbidity of a procedure that already has high risks of bleeding and thrombosis.

Validation of a second generation competitive enzyme immunoassay (CELISA) for the diagnosis of brucellosis in various species of domestic animals

A second generation competitive enzyme immunoassay (CELISA) for detection of bovine antibody to Brucella abortus was developed to eliminate reagent variables in the assay. This assay was different from earlier CELISA formats in that it used recombinant protein A and protein G immunoglobulin receptors (PAG), labelled with horseradish peroxidase, thus eliminating the requirement for polyclonal anti-mouse-enzyme conjugate for detection. This allowed standardization of the assay. The CELISA uses a monoclonal antibody specific for a common epitope of the O-polysaccharide (OPS) of smooth lipopolysaccharide (SLPS) derived from B. abortus S1119.3. This antibody did not react with PAG. This monoclonal antibody was used to compete with antibody in the bovine test serum to the smooth lipopolysaccharide (SLPS) antigen. Reaction of bovine antibody was then measured directly with the PAG enzyme conjugate. In this case, development of colour in the reaction indicated a positive reaction. The performance characteristics of the new CELISA, sensitivity, specificity and exclusion of antibody of B. abortus S19 vaccinated animals, were very similar to those of the classical CELISA and to the indirect enzyme immunoassay (IELISA) when using sera deemed positive by isolation of the bacterium, either from individual animals or from some animals on the premises. All sera were tested by the buffered antigen plate agglutination test (BPAT) and the complement fixation test (CFT). Only samples positive on both BPAT and CFT were considered as positive and only samples negative on both tests were used considered negative. Sufficient samples from cattle, swine, sheep and goats to validate the test were included based on OIE guidelines suggesting inclusion of a minimum of 300 positive and 1000 negative samples.

Second generation competitive enzyme immunoassay for detection of bovine antibody to Brucella abortus

A second generation competitive enzyme immunoassay (CELISA) for detection of bovine antibody to Brucella abortus was developed. This assay was different from previously developed CELISAs in that the detection reagent used was a recombinant combination of the receptor portions of protein A and protein G, labelled with horseradish peroxidase. This eliminates the need for polyclonal anti-mouse-enzyme conjugate reagents for detection thus allowing for true standardization. The assay utilized a monoclonal antibody specific for a common epitope of the O-polysaccharide (OPS) of smooth lipopolysaccharide (SLPS) derived from B. abortus S1119.3 but which did not react with protein A/G. This monoclonal antibody was used to compete with antibody in the bovine test serum. Binding of bovine antibody to the smooth lipopolysaccharide antigen was then measured directly with the protein A/G enzyme conjugate. In this case, development of colour in the reaction was indicative of the presence of bovine antibody. The performance characteristics, sensitivity, specificity and exclusion of B. abortus S19 vaccinated animals, of the assay were very similar to those of the classical CELISA.

Detection of Ovine Antibody toBrucella ovisby Indirect Enzyme Immunoassay

Because some batch-to-batch variation in the preparation of rough lipopolysaccharide (RLPS) from Brucella ovis has been experienced, several protocols were tested to establish the most reliable method for detection of antibody in indirect enzyme immunoassay. An early version of the assay gave a performance index (PI=sum of optimum percent sensitivity and percent specificity, determined by receiver operator characteristic analysis) of 198.6. This assay used RLPS from B. ovis as the antigen and a monoclonal antibody specific for bovine IgG(1) heavy chain-enzyme conjugate for detection. This was not repeatable using other batches of antigen. Newer versions of the assay generally had decreased sensitivity values, giving PIs of 193. Use of a recombinant protein A/G-enzyme conjugate did not improve the PI (PI=190), giving reduced specificity and higher sensitivity. The final version used B. abortus RB51 RLPS as the antigen and protein A/G-enzyme conjugate for detection, giving a PI of 197. Because of the batch uniformity of the B. abortus RB51 RLPS and the versatility of the protein A/G-enzyme conjugate, the latter version appears to be the most useful for diagnostic serology.

Towards single screening tests for brucellosis

This paper describes an indirect enzyme-linked immunosorbent assay (I-ELISA) and a fluorescence polarisation assay (FPA), each capable of detecting antibody in several species of hosts to smooth and rough members of the genus Brucella. The I-ELISA uses a mixture of smooth lipopolysaccharide (SLPS) and rough lipopolysaccharide (RLPS) as the antigen, and a recombinant protein A/G conjugated with horseradish peroxidase as the detection reagent. When using individually determined cutoff values, the SLPS/RLPS combined-antigen I-ELISA detected antibody in slightly more animals exposed to SLPS or to RLPS than did I-ELISA procedures using each individual antigen separately. Similarly, the assay using combined antigens detected antibody in slightly fewer animals not exposed to Brucella sp. When a universal cutoff of 10% positivity was used (relative to strongly positive control sera of each species), the overall performance index (percentage sensitivity plus percentage specificity) value decreased by 1.0 (from 199.4 to 198.4). In the FPA, it was not possible to use a universal cutoff without significant loss of performance. The overall sensitivity value for the FPA using the combined FPA antigen was 1.0% lower than using the O-polysaccharide (OPS) from SLPS and 9.1% higher than using the core antigen (CORE) from RLPS. When the combined antigen was used, the FPA specificity was slightly higher (1.2%) than from only the OPS, and considerably higher (12.6%) than the CORE. Overall, both the I-ELISA and the FPA with combined antigens were suitable as screening tests for all species of Brucella in the animal species tested.

Spinal anesthesia for cesarean section following inadequate labor epidural analgesia: a retrospective audit

BACKGROUND

High blocks have been reported when spinal anesthesia is used for cesarean section following inadequate labor epidural analgesia. We have therefore modified the practice at our institution to minimize this risk and conducted a retrospective observational study of outcome following the change of practice.

METHOD

The records of 115 women with inadequate epidural labor analgesia who required cesarean section between July 1998 and January 2002 were studied. No epidural boluses were administered in the 30 min preceding spinal anesthesia and a reduced spinal dose, median (range) 9.38 mg (7.5-11.3 mg) of 0.75% hyperbaric bupivacaine and fentanyl 15 microg (10-25 microg) was used. Patients were left sitting for 2 min and then positioned supine with left uterine displacement and were closely monitored for symptoms or signs that would suggest a high block.

RESULTS

No parturient developed a high spinal necessitating intubation, and there was no adverse neonatal outcome.

CONCLUSION

These findings do not conclusively establish this method as safe, but should spinal anesthesia for cesarean section following suboptimal labor epidural analgesia be considered, avoiding epidural boluses immediately preceding spinal injection, using a lower spinal dose, and delayed supine positioning following spinal injection may be advisable.

Enzyme immunoassay for the diagnosis of brucellosis: chimeric Protein A–Protein G as a common enzyme labeled detection reagent for sera for different animal species

A recombinant protein combining the immunoglobulin binding sites of Proteins A and G, conjugated with horseradish peroxidase was used as a universal detection reagent for the assessment of antibodies against Brucella spp. The reagent was applied in an indirect enzyme immunoassay for detection of antibodies to smooth lipopolysaccharide antigen in sera from Brucella spp. exposed and non-exposed cattle, sheep, goats and pigs and to antibodies to rough lipopolysaccharide in sheep, dogs and cattle. The results were similar to those obtained when murine monoclonal antibody-enzyme conjugates were used. An added advantage was that a universal cut-off for all tests using the proteins A and G detection reagent could be established, simplifying diagnostic interpretation of the data.

Rough Lipopolysaccharide ofBrucella abortusRB51 as a Common Antigen for Serological Detection ofB. ovis,B. canis, andB. abortusRB51 Exposure Using Indirect Enzyme Immunoassay and Fluorescence Polarization Assay

Rough lipopolysaccharide (RLPS) antigens were prepared from cultures of Brucella abortus RB51, B. ovis, and B. canis. The preparations were standardized by weight and tested with sera from cattle immunized with B. abortus RB51, sheep infected with B. ovis, and dogs infected with B. canis. Populations of unexposed animals of each species were also tested. The tests used were the indirect enzyme immunoassay (IELISA) using RLPS and the fluorescence polarization assay (FPA) using RLPS core fractions, labeled with fluorescein isothiocyanate. The IELISA using B. abortus RB51 RLPS antigen resulted in sensitivity and specificity values of 94.8% and 97.3%, respectively, when testing bovine sera, 98.5% and 97.8% when testing ovine sera, and 95.8% and 100% when testing dog sera. The IELISA using B. ovis RLPS antigen gave sensitivity and specificity values of 80.5% and 91.7%, respectively with bovine sera, 98.9% and 93.8% with sheep sera, and 70.8% and 79.8% with dog sera. The IELISA using B. canis RLPS antigen resulted in sensitivity and specificity values of 97.0% and 97.4%, respectively, with bovine sera, 96.2% and 96.3% with sheep sera, and 95.8% and 98.8% with dog sera. Labeling RLPS core from B. ovis and B. canis with fluorescein was not successful. B. abortus RB51 core labeled with fluorescein resulted in sensitivity and specificity values of 93.5% and 99.8%, respectively, with bovine sera and 78.1% and 99.0% with sheep sera. It was not possible to test the dog sera in the FPA.

The beta 5' loop of the pancreatic lipase C2-like domain plays a critical role in the lipase-lipid interactions

The structural similarities between the C-terminal domain of human pancreatic lipase (C-HPL) and C2 domains suggested a similar function, the interaction with lipids. The catalytic N-terminal domain (N-HPL) and C-HPL were produced as individual proteins, and their partitioning between the water phase and the triglyceride-water interface was assessed using trioctanoin emulsions (TC8). N-HPL did not bind efficiently to TC8 and was inactive. C-HPL did bind to TC8 and to a phospholipid monolayer with a critical surface pressure of penetration similar to that of HPL (15 mN m(-1)). These experiments, performed in the absence of colipase and bile salts, support an absolute requirement of C-HPL for interfacial binding of HPL. To refine our analysis, we determined the contribution to lipid interactions of a hydrophobic loop (beta 5') in C-HPL by investigating a HPL mutant in which beta 5' loop hydrophobicity was increased by introducing the homologous lipoprotein lipase (LPL) beta 5' loop. This mutant (HPL-beta 5'LPL) penetrated into phospholipid monolayers at higher surface pressures than HPL, and its level of binding to TC8 was higher than that of HPL in the presence of serum albumin (BSA), an inhibitory protein that competes with HPL for interfacial adsorption. The beta 5' loop of LPL is therefore tailored for an optimal interaction with the surface of triglyceride-rich lipoproteins (VLDL and chylomicrons) containing phospholipids and apoproteins. These observations support a major contribution of the beta 5' loop in the interaction of LPL and HPL with their respective substrates.

Validation of the fluorescence polarization assay for detection of milk antibody to Brucella abortus

A fluorescence polarization assay (FPA) for detection of antibody to Brucella abortus in individual milk samples was developed and validated. Samples from 190 cattle from which B. abortus was isolated; milk samples from cattle in herds infected with B. abortus (n = 1,086) and positive in the milk ring test (MRT), as well as milk samples from Canadian cattle (with no evidence of brucellosis, n = 2,974) were tested by the indirect enzyme immunoassay (IELISA) and the FPA. The sensitivity (based on samples from culture positive cattle) and specificity (based on Canadian milk samples) of the IELISA and the FPA were 100%. The relative sensitivity value obtained with milk from cattle of infected herds and the specificity values of the IELISA were 98.5 and 99.9%, respectively. The relative sensitivity and specificity of the FPA with the same samples were 82.2 and 99.4% using a cutoff value of 90 millipolarization units (mP). The low relative sensitivity value of the FPA was shown, by competitive enzyme immunoassay (CELISA), to be due to vaccinal antibody (assumed as vaccinal antibody against B. abortus Sl19 is excluded by the FPA and CELISA but not by the MRT and the IELISA), present in some of the milk samples. The FPA is a homogeneous assay which, unlike the MRT and the IELISA, may be used for testing in the field.