Safety of DOACs in patients with Child-Pugh Class C cirrhosis and trial fibrillation

Background

Anticoagulation (AC) is used for stroke prevention in atrial fibrillation (AF). Direct Oral Anticoagulants (DOACs) are safe in patients with AF without cirrhosis, they are hardly studied in patients with advanced cirrhosis. Our study evaluates the safety and outcomes of DOACs in patients with Child-Pugh class C cirrhosis (CPC).

Methods

We queried TriNetX Database. Patients with CPC and AF were divided into three cohorts: patients on DOACs, no AC, and warfarin. Three study arms were created using a 1:1 propensity score matching system (PSM).

Results

Totally 16 029 patients met the inclusion criteria. Of those, 20.2% (n = 3235) were on DOACs, 47.1% (n = 7552) were not on AC, and 32.7% (n = 5242) were on warfarin. First arm comparing AC versus no AC, a statistically significant benefit was identified in 3-year mortality risk (47% vs 71%, P < 0.0001) and transplant status (17% vs 5%, p < 0.0001) with AC. However, no significant difference was identified regarding intracranial hemorrhage and GI bleeding risk. Second arm comparing patients on DOACs versus no AC, we identified mortality benefit (40% vs 72%, P < 0.0001) and a higher transplant rate (9% vs 3.2%, P < 0.0001) with DOACs. Intracranial hemorrhage rates (6% vs 4%, P = 0.03) were higher in patients on DOACs. Third arm comparing patients on DOACs versus Warfarin, a statistically significant lower risk of intracranial hemorrhage (6.6% vs 8.7%, P = 0.004) and GI bleed (2% vs 2.4%, P < 0.0001) were identified in patients on DOACs.

Conclusion

Anticoagulation is safe in patients with CPC with AF and may provide a mortality benefit. DOACs are a safer alternative to warfarin.

The Use of Glucagon-like Peptide-1 Receptor Agonists in Patients with Type 2 Diabetes Mellitus Does Not Increase the Risk of Pancreatic Cancer: A U.S.-Based Cohort Study

BACKGROUND

GLP-1 RAs are widely used for T2DM treatment due to their cardiorenal and metabolic benefits. This study examines the risk of pancreatic cancer with GLP-1 RA use in patients with T2DM.

METHODS

We analyzed TriNetX's deidentified research database using the U.S. Collaborative Network comprising 62 healthcare organizations across the U.S.A. Patients with T2DM were split into two cohorts: one receiving GLP-1 RAs, and one not receiving GLP-1 RAs. We excluded patients with known risk factors for pancreatic cancer, including pancreatic cysts, a personal or family history of BRCA1, BRCA2, CDKN2A, KRAS, MEN1, MLH1, MSH2, NOTCH1, PALB2, PMS2, and PRSS1S genes, family history of pancreatic cancer, and VHL syndrome. Using a 1:1 propensity score-matching model based on baseline characteristics and comorbidities, we created comparable cohorts. We then compared the rate of pancreatic cancer between the two cohorts at a 7-year interval.

RESULTS

Out of 7,146,015 identified patients with T2DM, 10.3% were on a GLP-1 RA and 89.7% were not. Post-PSM, 721,110 patients were in each group. Patients on GLP-1 RAs had a 0.1% risk compared to a 0.2% risk of pancreatic cancer in the 7-year timeframe.

CONCLUSION

The use of GLP-1 RAs in patients with type 2 diabetes mellitus (T2DM) does not appear to substantially elevate the risk of pancreatic cancer; in fact, it may potentially exert a protective effect.

The Use of Pre-Endoscopic Metoclopramide Does Not Prevent the Need for Repeat Endoscopy: A U.S. Based Retrospective Cohort Study

BACKGROUND

Peptic ulcer disease (PUD) can cause upper gastrointestinal bleeding (UGIB), often needing esophagogastroduodenoscopy (EGD). Second-look endoscopies verify resolution, but cost concerns prompt research on metoclopramide's efficacy compared to erythromycin.

METHODS

We analyzed the Diamond Network of TriNetX Research database, dividing UGIB patients with PUD undergoing EGD into three groups: metoclopramide, erythromycin, and no medication. Using 1:1 propensity score matching, we compared repeat EGD, post-EGD transfusion, and mortality within one month in two study arms.

RESULTS

Out of 97,040 patients, 11.5% received metoclopramide, 3.9% received erythromycin, and 84.6% received no medication. Comparing metoclopramide to no medication showed no significant difference in repeat EGD (10.1% vs. 9.7%, p = 0.34), transfusion (0.78% vs. 0.86%, p = 0.5), or mortality (1.08% vs. 1.08%, p = 0.95). However, metoclopramide had a higher repeat EGD rate compared to erythromycin (9.4% vs. 7.5%, p = 0.003), with no significant difference in transfusion or mortality.

CONCLUSIONS

The need to repeat EGD was not decreased with pre-EGD use of metoclopramide. If a prokinetic agent is to be used prior to EGD, erythromycin shows superior reduction in the need of repeat EGD as compared to metoclopramide.

Use of proton pump inhibitors improves outcomes in mild acute pancreatitis: A nationwide cohort study

Previous studies showed a potential anti-inflammatory effect of proton pump inhibitors (PPI) as well as possible inhibition of pancreatic secretion. This presents the question of their possible use in acute pancreatitis (AP). Current clinical evidence does not address the role of PPI and the present review for possible therapeutic use and safety is lacking. Therefore, our study aims to address the role of PPI in the management of AP and their association with the different outcomes of AP. We queried the Diamond Network through TriNetX-Research Network. This network included 92 healthcare organizations. Patients with mild AP with Bedside Index of Severity in Acute Pancreatitis (BISAP) score of Zero regardless of etiology were divided into 2 cohorts; 1st cohort included patients on PPI, and 2nd cohort included patients not on any PPI. Patients with BISAP score equal to or more than 1 or on PPI prior to the study date were excluded. Two well-matched cohorts were created using 1:1 propensity-scored matching model between cohorts. We compared the incidence of intensive care unit admission, mortality, and other associated complications. A total of 431,571 patients met the inclusion criteria. Of those, 32.9% (n = 142,062) were on PPI, and 67% (n = 289,509) were not on any PPI. After propensity matching, the sample included 115,630 patients on PPI vs 115,630 patients not on PPI. The PPI group had a lower rate of mortality (3.7% vs 4.4%, P < .001), a lower rate of intensive care unit admission (3.9% vs 5.5%, P < .001), a lower rate of necrotizing pancreatitis (1.1% vs 1.9%, P < .001), a lower rate of Hospital-Acquired Pneumonia (3.6% vs 4.9%, P < .001), a lower rate of respiratory failure (2.8% vs 4.2%, P < .001), and a lower rate of acute kidney injury (6.9% vs 10.1%, P < .001). There was no statistical difference in the rate of Clostridium difficile infection between the 2 cohorts (0.9% vs 0.8%, P = .5). The use of PPI in mild AP with a BISAP-score of zero is associated with reduced pancreatitis-related complications and improved mortality. Prospective studies are needed to confirm these findings.

Biliary Cyst: An Unusual Cause of Cholestasis Post Cholecystectomy

Biliary cysts are relatively uncommon and they can be congenital or acquired and can have various presentations such as cholelithiasis, cholangitis, jaundice, and pancreatitis. Biliary cysts are associated with a high risk of biliary cancers and such risk increases with age. Identification of biliary cysts warrants an aggressive approach to lower cancer risk. Surgical management has a high success rate and it lowers morbidity, mortality, and cancer risk. We present a 40-year-old female who had a cholecystectomy in 2016. She presented with obstructive jaundice and was found to have a class I biliary cyst. She underwent endoscopic retrograde cholangiopancreatography with stenting which led to complete resolution of her symptoms. Later, she underwent elective Roux-en-Y hepaticojejunostomy with cyst resection three months later. She underwent a successful recovery.

Acute Gallstone Pancreatitis in Pregnancy: A Multidisciplinary Approach

A common cause of gastrointestinal-related hospitalizations in the United States of America is acute pancreatitis (AP), with an annual incidence of up to 80 cases per 100,000 people. The incidence of AP in pregnancy varies and is approximately 1 in 1000 to 1 in 10,000 births due to the prevalence of obesity and gallstone-related conditions. Deciding on the timing of surgical intervention in acute biliary pancreatitis during pregnancy remains challenging, and there are no consensus recommendations. Gallstone pancreatitis has a high recurrence rate of up to 50% during the first trimester. A 30-year-old G3P2 at 34 weeks of gestation presented to the emergency room (ER) with recurrent intermittent sudden severe epigastric and right upper quadrant abdominal pain radiating to the back. She had no history of alcohol consumption, and lipid studies were normal on presentation. A right upper quadrant ultrasound scan showed cholelithiasis without signs of acute cholecystitis and a common bile duct diameter of 0.5 cm. However, her serum lipase level was 824, compared to normal levels on her previous ER visits. Other significant labs included elevated alkaline phosphatase (ALP) of 125 and mild transaminitis, with alanine transaminase (ALT) and aspartate aminotransferase (AST) levels of 84 and 57, respectively. She was admitted on account of suspected gallstone pancreatitis and was treated supportively with IV fluids and adequate pain control with opioids. A subsequent magnetic resonance cholangiopancreatography (MRCP) revealed no obvious choledocholithiasis. After consultation with the obstetrics, gastroenterology, and general surgery teams, it was decided to defer cholecystectomy until after delivery. The patient was induced at 36 weeks of gestation, and she had an uneventful vaginal delivery. Two weeks later, she had an elective laparoscopic cholecystectomy with no complications.

Utilization of direct oral anticoagulants in a Saudi tertiary hospital: a retrospective cohort study

OBJECTIVE

This study aimed to assess the appropriateness of direct oral anticoagulants (DOACs) utilization in a Saudi tertiary hospital.

PATIENTS AND METHODS

Adult inpatients and outpatients diagnosed with atrial fibrillation, deep vein thrombosis, or pulmonary embolism were included in a retrospective cohort study. Patients received at least one month of apixaban, rivaroxaban, or dabigatran. The duration of the study at the Armed Forces Hospital Southern Region in Khamis Mushait, Saudi Arabia, was from January 1, 2019, to December 31, 2021. The study assessed the appropriateness of DOACs dosing, initial and follow-up monitoring, the presence of clinically significant interactions, and treatment duration adherence.

RESULTS

778 patients were included in the analysis (mean age 71.34 ± 15.98 years, equal male and female representation). Rivaroxaban was administered to 40.8% of the patients, while apixaban and dabigatran were administered to 31.02% and 28.18% of the patients, respectively. The most prevalent indication for DOACs was atrial fibrillation (72.84%), followed by deep vein thrombosis and pulmonary embolism (27.16%). The most prevalent category of medication errors was inappropriate maintenance dose (41.7%), followed by inappropriate initial dose (37.97%) and lack of laboratory parameter monitoring (36.42%). 31.5 percent of the study sample lacked baseline renal functions, while 24.5% of patients lacked baseline liver functions. 115 patients (14.8%) had potential clinically significant interactions. Regarding treatment duration, 232 patients (29.8%) were improperly prescribed DOACs based on their indications.

CONCLUSIONS

In a significant proportion of DOAC patients, the prescribed rational DOAC utilization parameters were not implemented. The results of the study provide specific improvement areas and objectives for Anticoagulation stewardship programs.

Daptomycin-Induced Acute Liver Failure: A Rare Case Report

Acute liver failure (ALF) is characterized by severe liver injury, encephalopathy, and impaired coagulation/synthetic function. Drug-induced liver injury (DILI) can rarely, in a dose-dependent manner, lead to ALF. This article presents a rare case of daptomycin-induced acute liver failure in a patient with no prior liver disease. A 73-year-old male with multiple comorbidities including heart failure, diabetes, and chronic kidney disease received daptomycin treatment for diabetic left foot osteomyelitis. Five days after starting therapy, he developed weakness, jaundice, and drowsiness, leading to ICU admission. Physical examination and labs revealed hepatomegaly, elevated liver enzymes and abnormal ultrasound findings. Autoimmune and infectious causes were ruled out. Daptomycin was discontinued, and the patient's labs showed significant improvement within three days. One week after recovery from acute liver failure, he experienced cardiogenic shock due to worsening of his underlying heart failure and was transferred to the Cardiac ICU before ultimately being discharged to inpatient hospice care. To our best knowledge, this is the first reported case of daptomycin-induced acute liver failure, presenting with massive liver enzyme elevations, synthetic dysfunction, and encephalopathy. The Naranjo scale score suggests a probable causal relationship between daptomycin and liver injury. While a few cases of daptomycin-induced liver injury have been reported, there are no previous reports of acute liver failure. The rapid development of liver failure following daptomycin administration and subsequent recovery after discontinuation is noteworthy. However, various confounding factors and the mechanism of daptomycin-induced liver failure remain unclear. Further research is needed to identify predisposing factors and better understand this rare complication. While rare, this care also raises caution to follow liver function closely while prescribing daptomycin.

[Congenital analbuminemia complicated by relapsing acute coronary syndrome : A case report and literature review]

Congenital analbuminemia (CAA) is a very rare disorder with an estimated prevalence of less than one in one million. This anomaly can be lethal at birth and in early infancy but it's not very symptomatic in adulthood. The clinical signs are edema, lipodystrophy, fatigue… Hypercholesterolemia is the main biological disorder and it predisposes to cardiovascular complications. The mild symptoms of CAA leads to delay diagnosis. That's why clinical and biological signs of this disorder should be known by both of biologist and clinician to establish an early diagnosis in order to prevent cardiovascular complications. We report a new case of congenital analbuminemia complicated by recurrent acute coronary artery disease in 34-year-old man. This complication has been reported only once according to the register of analbuminemia cases.

A contemporary definition of periprocedural myocardial injury after percutaneous coronary intervention of chronic total occlusions

Background

Coronary chronic total occlusion (CTO) recanalization represents the most technically challenging percutaneous coronary interventions (PCI). The complexity harbours a significant increased risk risk for complications with CTO PCI as compared to non-CTO PCI. However there are evidenced biomarker cut-off levels that help to identify those patients at risk for an unfavorable clinical outcome.

Objective

This study aimed to assess the prognostic impact of postprocedural troponin T increase and mortality in patients undergoing CTO-PCI in order to define the threshold, where procedural related myocardial injury drives mortality.

Methods

We enrolled a total of 3712 consecutive patients undergoing PCI for at least one CTO lesion and performed comprehensive troponin Tmeasurements 6, 8, and 24 hours after the procedure. All-cause mortality was defined as the primary study endpoint.

Results

Using spline curve analysis, we observed that a more than 18-fold increase of troponin above the upper reference limit (URL) is significantly associated with mortality. In the Cox regression analysis we observed a crude hazard ratio (HR) of 2.32 (95% CI 1.83–2.93, P&lt;0.001) for a ≥18fold increase compared to patients with post-procedural troponin increase &lt;18-fold of the URL.Results remained virtually unchanged after bootstrap- or clinical confounder-based adjustment.

Conclusion

This large-scale outcome study demonstrates for the first time the prognostic value of post-procedural troponin T elevation after PCI in CTO patients. We could define a threshold for procedure related myocardial injury in CTO patients that differ non- CTO patients and may help guide the postprocedural clinical care in this high risk patient population.

Figure 1

Funding Acknowledgement

Type of funding source: None

A218 LISTERIA MONOCYTOGENES MENINGITIS IN A NEWLY DIAGNOSED PATIENT WITH INFLAMMATORY BOWEL DISEASE: A CASE REPORT

Background

Anti-Tumor Necrosis Factor (TNF) is a frequently utilized therapy in the treatment of Inflammatory Bowel Disease (IBD). Opportunistic infections are a known but an infrequently encountered complication. Listeria monocytogenes (LM) is an aerobic gram-positive intracellular bacillus. Clinical presentation of infection is host dependent, ranging from self-limited illnesses in immunocompetent individuals to life-threatening sepsis and meningitis in the immunocompromised. TNF plays a crucial role in host’s defense against LM. Although published in adults, few case reports have documented invasive LM in children receiving infliximab (IFX), an anti-TNF agent used in IBD therapy.

Aims

Describe an adolescent with IBD-unclassified (IBD-U) in whom LM sepsis and meningitis was diagnosed after induction therapy with intravenous (IV) IFX.

Methods

Case report and literature review.

Results

A 15-year-old girl presented with 2-week history of progressive abdominal pain, bloody diarrhea, urgency, nocturnal stooling, tenesmus, and weight loss. She had been afebrile, with no history of exposures. Examination revealed pallor and tenderness in the right and left lower quadrants. Investigations showed elevated white cell count (WBC), platelets, inflammatory markers, and low albumin. Abdominal ultrasound showed thickening of the descending and sigmoid colon. Stool multiplex PCR was negative. Colonoscopy showed Mayo 3 pancolitis. The terminal ileum was not intubated and endoscopy was normal. She was diagnosed with IBD-U. Due to poor response to high dose IV steroids, IV IFX (after documenting normal vaccination titers) was given with good clinical response and no adverse effects; she was discharged on tapering prednisone. She re-presented 3 days later with fever, severe headaches, photophobia, and neck stiffness. Her IBD remained quiescent. She had consumed a cold meat sandwich 10 days prior. Antibiotics were started as investigations showed leukocytosis and very high inflammatory markers. Brain MRI showed pus in the lateral ventricles. Cerebrospinal fluid (CSF) analysis showed WBC 1832 x106/L, low glucose, and high protein. Blood and CSF cultures detected LM. She defervesced within 24 hours and completed a 21-day course of Ampicillin monotherapy. 2-month follow up showed IBD in continuous remission on IFX with no neurological sequalae, and a normal brain MRI.

Conclusions

This is the youngest patient with IBD reported with invasive listeriosis secondary to IFX and adds to 3 cases in children. It highlights the importance of vigilance when evaluating IBD patients with fever during IFX-based therapy. Physicians should be reminded of such patients’ immunocompromised state and their high risk of acquiring opportunistic infections. It is unclear if listeriosis avoidance precautions, currently recommended in pregnant women, should be adopted in patients receiving anti-TNF therapy.

Funding Agencies

None

Perception Versus Reality in the Cost of Orthopedic Trauma Implants

OBJECTIVE

Health care costs are increasing in medicine and in orthopedics. Device choice in orthopedic cases can impact the cost of the procedure and thus result in cost savings. This study aims to determine whether orthopedic attendings and residents accurately estimate device costs they are implanting in trauma cases and whether costs would influence their surgical device selection.

DESIGN

Using nationally published average cost data for 13 implants, a survey was distributed at 6 US academic centers. Respondents were asked to select the correct cost from cost ranges. They also answered yes/no questions about their choices regarding published research outcomes for specific fractures. Residents' answers were compared with faculty answers using t tests for each cost estimate question, and chi-square tests for yes/no questions and frequencies.

RESULTS

A total of 51 faculty members and 76 residents responded. Attending estimates were closer to the actual cost for most devices. The average total error in cost estimate for all 13 implants was $11,288.36 for residents (35.6% difference) and $10,208.33 for faculty members (32.2% difference). Significantly more faculty members estimated costs within 10% versus residents. When asked if the literature showed differences in outcome when using different implants to treat 4 common fractures, most answered these questions correctly. Further, 71.1% of residents said their choice of implant would change if costs affected physician reimbursements versus 58% for faculty members.

CONCLUSIONS

Our data indicate orthopedic physicians are not aware of true implant costs and nearly half of attendings would not consider cost as a factor in deciding between equivalent implants, even if this affected their reimbursement. Most notably, participants showed a poor ability to closely estimate the cost of more expensive implants (actual device cost greater than $2000). Our results suggest that medical cost containment should be stressed to the next generation of surgeons.

The first record of Centrocestus formosanus (Nishigori, 1924) (Digenea: Heterophyidae) in Egypt

The life cycle of Centrocestus formosanus (Digenea: Heterophyidae) was to be successfully completed in the laboratory in the present study. Hundreds of the thiarid snail, Melanoides tuberculata, were collected from the main water course Mansouriya Canal, Giza Governorate, Egypt. The snails were individually exposed to artificial light to determine possible infection with trematode larvae. Fifteen snails were found infected with opthalmopleurolophocercous cercariae (infection index of 1.97). These opthalmopleurolophocercous cercariae shedded from snails were collected and placed in an aquarium with fish intermediate host, Gambusia affinis, to obtain metacercariae encysted in the gills. The gills with metacercariae were fed to albino rats, Rattus norvegicus, to obtain the adult worms. Adult worms were recovered in the small intestine of rats at 7 days after infection and they were identified as Centrocestus formosanus based on the morphological characteristics and the comparison with the previous descriptions in the literature. They were small, 518 × 324 μm in average size and had characteristic 32 circumoral spines around the oral sucker. The morphological characteristics of the developmental stages, from cercariae to adults, of this heterophyid fluke were given here. Therefore, the presence of this fluke is to be confirmed for the first time in Egypt by the present study.

145 THE INFLUENCE OF PROPYLENE GLYCOL DRENCHING ON THE SUPEROVULATORY RESPONSE AND EMBRYO QUALITY IN HIGH-YIELDING DAIRY COWS

Genetic improvement of dairy cows increased markedly over the last decades; this has marked increased milk yield, which has been associated with reduced fertility parameters. The objective of this study was to determine the effects of feeding propylene glycol (PG) on superovulatory responses of 50 dairy cows and on their embryo quality and quantity. Starting at 1 week before the application of superovulatory regimen, each cow received once daily an oral dose of 150 g of PG (PG group) or water (control group). All cows were superovulated with a total dose of 400 mg of FSH administrated twice daily in decreasing doses over 4 consecutive days. Embryos were recovered nonsurgically 7.5 days after the onset of oestrus using a 2-way catheter. Evaluation of embryo quality was done according to the IETS manual based on 1 to 4 grades. Grade 1 embryos were transferred after freezing; grade 2 and 3 embryos were freshly transferred. The results showed that the number of total ova/embryos recovered, grade 1 embryos, and the number of transferable embryos were significantly higher (P = 0.048, 0.015, and 0.014, respectively) in the PG group (10.33 ± 1.9, 7.08 ± 1.7, and 7.92 ± 1.6, respectively) when compared with control group (6.09 ± 0.9, 2.11 ± 0.45, and 3.92 ± 1.25, respectively). Insignificant increase in grade 2 and grade 3 embryos was indicated in the control group (1.37 ± 0.3 and 0.51 ± 0.18, respectively) when compared with PG group (0.75 ± 0.28 and 0.25 ± 0.13, respectively). On the other hand, the results indicated that there was an increase in the number of degenerated embryos and unfertilized ovum in the PG group (2.33 ± 0.85) compared with control group (2.09 ± 0.6). In conclusion, these results suggested that administration of PG has the ability to positively improve the superovulatory response and embryo quality in high-yielding dairy cows.

Enhanced Čerenkov second-harmonic emission in nonlinear photonic structures

We study experimentally and theoretically the Čerenkov-type second-harmonic generation in a one-dimensional nonlinear photonic crystal. We demonstrate that the power of emitted second-harmonic can be enhanced 270 times by varying the angle of incidence of the fundamental beam such that the reciprocal lattice vector of the crystal can be used to compensate for the phase mismatch in the transverse direction enabling interaction in the nonlinear Bragg diffraction regime.

Modulation of the Th1/Th2 bias by an immunoglobulin histamine complex in the ovalbumin allergy mouse model

Vaccination with the antiallergic drug Histaglobin is used to treat a broad range of human allergic diseases including bronchial asthma, allergic rhinitis, and atopic dermatitis. In order to further elucidate its functional activity, Histaglobin was investigated in an in vivo mouse allergy model. Mice were sensitized with ovalbumin either prior to or after Histaglobin treatment, and its antiallergic potential was evaluated. Ovalbumin-sensitized mice exhibited increased serum levels of IL-4, tumor necrosis factor alpha (TNF-alpha), and an increase of total and ovalbumin-specific IgE; total and ovalbumin-specific IgG levels were also elevated. Subsequent administration (therapeutic treatment) of Histaglobin resulted in a decrease of total and specific serum IgE levels; total and specific IgG1 serum levels were reduced by more than 50% and 45%, respectively; the mice displayed a down-regulation of IL-4 and TNF-alpha serum levels and showed increased levels of IFN-gamma and IgG2a. Mice pretreated with Histaglobin, prior to ovalbumin sensitization (prophylactic treatment), were found to be widely unresponsive to ovalbumin. They exhibited higher serum levels of IFN-gamma and IgG2a (total and specific) compared to saline-treated control mice. The inhibitory effects were still observed 1 month post-immunization. Our data, indicating a Histaglobin-induced modulation of the Th1/Th2 balance in favour of Th1, correspond with the well-known antiallergic activity of Histaglobin observed in patients.

Effectiveness of selective genotyping for detection of quantitative trait loci: an analysis of grain and malt quality traits in three barley populations

Marker genotype data and grain and malt quality phenotype data from three barley (Hordeum vulgare L.) mapping populations were used to investigate the feasibility of selective genotyping for detection of quantitative trait loci (QTLs). With selective genotyping, only individuals with high and low phenotypic values for the trait of interest are genotyped. Here, genotyping of 10 to 70% of each population (i.e., 5 to 35% in each tail of the phenotypic distribution) was considered. Genomic positions detected by selective genotyping were compared to QTL position estimates from interval mapping analysis using marker genotype data from the entire population. Selective genotyping reliably detected almost all of the mapped QTLs, often with only 10% of the population genotyped. Selective genotyping also detected spurious QTLs in regions of the genome where no significant QTL had been mapped. Even with additional genotyping to verify putative QTLs, the total genotyping effort for detection of QTLs for a single trait by selective genotyping was usually less than 30% of that required for conventional interval mapping. Simultaneous investigation of two or more traits by selective genotyping would require additional genotyping effort, but could still be worthwhile.

QTLs affecting kernel size and shape in a two-rowed by six-rowed barley cross

The suitability of barley ( Hordeum vulgare L.) grain for malting depends on many criteria, including the size, shape and uniformity of the kernels. Here, image analysis was used to measure kernel size and shape attributes (area, perimeter, length, width, F-circle and F-shape) in grain samples of 140 doubled-haploid lines from a two-rowed (cv Harrington) by six-rowed (cv Morex) barley cross. Interval mapping was used to map quantitative trait loci (QTLs) affecting the means and within-sample standard deviations of these attributes using a 107-marker genome map. Regions affecting one or more kernel size and shape traits were detected on all seven chromosomes. These included one near the vrs1 locus on chromosome 2 and one near the int-c locus on chromosome 4. Some, but not all, of the QTLs exhibited interactions with the environment and some QTLs affected the within-sample variability of kernel size and shape without affecting average kernel size and shape. When QTL analysis was conducted using data from only the two-rowed lines, the region on chromosome 2 was not detected but QTLs were detected elsewhere in the genome, including some that had not been detected in the analysis of the whole population. Analysis of only the six-rowed lines did not detect any QTLs affecting kernel size and shape attributes. QTL alleles that made kernels larger and/or rounder also tended to improve malt quality and QTL alleles that increased the variability of kernel size were associated with poor malt quality.

Calpha methylation in molecular recognition. Application to substance P and the two neurokinin-1 receptor binding sites

Two binding sites NK-1M (major, more abundant) and NK-1m (minor) are associated with the neurokinin-1 receptor. For the first time with a bioactive peptide, the Calpha methylation constraint, shown to be a helix stabiliser in model peptides, was systematically used to probe the molecular requirements of NK-1M and NK-1m binding sites and the previously postulated bioactive helical conformation of substance P (SP). Seven Calpha methylated analogues of the undecapeptide SP (from position 5-11) have been assayed for their affinities and their potencies to stimulate second messenger production. The consequences of Calpha methylation on the structure of SP have been analysed by circular dichroism and nuclear magnetic resonance combined with restrained molecular dynamics. The decreased potencies of six out of these seven Calpha methylated SP analogues do not allow the identification of any clear-cut differences in the structural requirements between the two binding sites. Strikingly, the most active analogue, [alphaMeMet5]SP, leads to variable subnanomolar affinity and potency when interacting with the NK-1m binding site. The conformational analyses show that the structural consequences associated with Calpha methylation of SP are sequence dependent. Moreover, a single Calpha methylation is not sufficient by itself to drastically stabilize a helical structure even pre-existing in solution, except when Gly9 is substituted by an alpha-aminoisobutyric acid. Furthermore, Calpha methylation of residues 5 and 6 of SP in the middle of the postulated helix does not stabilize, but decreases (to different extents) the stability of the helical structure previously observed in the 4-8 domain of other potent SP analogues.

Immunostimulation by the synthetic lipopeptide P3CSK4: TLR4-independent activation of the ERK1/2 signal transduction pathway in macrophages

Synthetic lipopeptides based on bacterial lipoprotein are efficient activators for monocytes/macrophages inducing the release of interleukin (IL)-1, IL-6, tumour necrosis factor-alpha (TNF-alpha), reactive oxygen/nitrogen intermediates, and the translocation of nuclear factor kappaB (NFkappaB). In this report we investigate the signal transduction pathways involved in leucocyte activation by the synthetic lipopeptide N-palmitoyl-S-[2,3-bis(palmitoyloxy)-(2R,S)-propyl]-(R)-cysteinyl-seryl-(lysyl)3-lysine (P3CSK4). We show that P3CSK4 activates mitogen-activated protein (MAP)-kinases ERK1/2 and MAP kinase (MAPK)-kinases MEK1/2 in bone-marrow-derived macrophages (BMDM) and in the macrophage cell line RAW 264.7. Additionally, we could detect differences between the P3CSK4 and lipopolysaccharide (LPS)-induced phosphorylation of MAP kinases: Different levels in phosphorylation were found both in kinetics and dose-response using RAW 264.7 cells or BMDM from BALB/c and LPS responder mice (C57BL/10ScSn) or LPS non-responder mice (C57BL/10ScCr). The lipopeptide activated the MAPK-signalling cascade in both LPS responder and non-responder macrophages, whereas LPS induced the MAPK signalling pathway only in macrophages derived from LPS responder mice. An approximately 70% decrease of lipopeptide induced NFkappaB translocation and an about 50% reduction of nitric oxide (NO) release was observed in the presence of anti-CD14. These data correspond to the reduction of phosphorylation of ERK1/2 after stimulation with P3CSK4 in the presence of anti-CD14 antibodies. Inhibition of MEK1/2 by PD98059 completely reduced the lipopeptide-induced phosphorylation of ERK1/2 indicating that MEK1/2 are solely responsible for the phosphorylation of the downstream-located MAP kinases ERK1/2.

Lipopeptide adjuvants: generation of lactate dehydrogenase isoenzyme-specific antibodies for immunochemical diagnosis

Lactate dehydrogenase catalyzes the final step in glycolysis, the interconversion of pyruvate and lactate. The tetrameric enzyme is composed of one or two subunits (H and/or M) resulting in five isoenzyme forms: LDH-H4, -H3M1, -H2M2, -H1M3, and -M4. The relative distribution of the LDH isoenzymes is tissue dependent and a significant marker for the diagnosis of hepatoma of the liver, myocardial infarction, muscular dystrophy, and a wide variety of other acute and chronic diseases to be detected by alterations of the LDH isoenzyme pattern in serum. Immunochemical approaches to the routine determination of LDH depend on isoenzyme specific antibodies. Since the H- and M-subunits for human LDH are highly homologous, LDH isoenzyme specific antibodies for immunochemical monitoring are hard to generate. Here we present data on the generation and characterization of LDH isoenzyme-specific mono- and polyclonal antibodies in different species in the presence of lipopeptide adjuvants. Western-Blot and ELISA analysis showed that antisera and monoclonal antibodies recognize their homologous antigens with high specificity and are therefore suitable for immunochemical monitoring of the LDH isoenzymes H4 and M4. In addition, they can be used for the determination of LDH isoenzyme specific activity which is an essential prerequisite for online amperometric immunosensor monitoring.

Immunostimulation by bacterial components: I. Activation Of macrophages and enhancement of genetic immunization by the lipopeptide P3CSK4

Synthetic lipopeptides derived from the N-terminus of bacterial lipoprotein constitute potent macrophage activators and polyclonal B-lymphocyte stimulators. They are also efficient immunoadjuvants in parenteral, oral and nasal immunization either in combination with or after covalent linkage to an antigen. Here we show how alterations in the molecular structure influence their biological properties indicating P3CSK4 as one of the most active members of a lipopentapeptide fatty acid library. This compound resulted in a most pronounced macrophage stimulation as indicated by NO release, activation of NFkappaB translocation, and enhancement of tyrosine protein phosphorylation. Furthermore, P3CSK4 activates/represses an array of at least 140 genes partly involved in signal transduction and regulation of the immune response. Finally we have evidence that P3CSK4 constitutes an effective adjuvant for DNA immunizations, especially increasing weak humoral immune responses. Our findings are of importance for further optimizing both conventional and genetic immunization, and for the development of novel synthetic vaccines.

The anti-allergic drug histaglobin inhibits NF-kappaB nuclear translocation and down-regulates proinflammatory cytokines

The transcription factor NF-kappaB is the central regulator for the expression of various genes involved in inflammation, infection and immune response including the genes for IL-1beta, TNF-alpha, IL-6 and leukocyte adhesion molecules. Here, we show that the anti-allergic drug histaglobin down-regulates the release of IL-1beta, TNF-alpha, IL-6 and IL-10 in human peripheral blood mononuclear cell cultures. This down-regulatory effect becomes even more pronounced when the cultures are simultaneously activated with the T-lymphocyte mitogen phytohemagglutinin (PHA) or with the B-lymphocyte and macrophage activator lipopeptide (P(3)CSK(4)). We also demonstrate that histaglobin inhibits the nuclear translocation of NF-kappaB in response to TNF-alpha or lipopolysaccharide (LPS) in bone marrow-derived macrophages of Balb/c mice. The inhibitory effect of histaglobin on NF-kappaB activation and cytokine release might be responsible for its anti-allergic effect as demonstrated in clinical studies.

Immunostimulatory activity of the bacterial extract OM-8

The bacterial extract OM-89 used for the prevention and treatment of recurrent urinary tract infections constitutes an effective immunostimulant in vitro and in vivo. Here we demonstrate that OM-89 shows mitogenic properties towards murine spleen cell cultures from LPS responder and non-responder mice. In macrophages the extract induces the translocation of NF-kappaB into the cell nucleus and RNI (radical nitrogen intermediates) release, which could be attributed to single fractions of the extract. Our findings on the in vitro immunostimulatory effect of OM-89, as well as its immunogenic and adjuvant properties, are of importance for understanding its therapeutic efficacy as demonstrated in clinical studies.

Variability of adjustments to indices in determining patient risk in biochemical screening

It has long been appreciated that the measurement of biochemical parameters for prenatal screening for neural tube defects, and later aneuploidy, is not as simple as measuring hemoglobin or hematocrit. Early in the game, it was recognized that there are gestational age curves, and that since alpha-fetoprotein (AFP), for example, is a fetal product, its distribution varies as a function of maternal plasma volume, and therefore the weight of the mother. A number of different adjustment factors have been used for AFP and other parameters for years, with varying degrees of consistency and reliability. Here we review a number of adjustments that have been used, and try to give priority to those that have been most effective. Furthermore, laboratories and programs need to be cognizant that with newer parameters being added, the specifics of requirements will vary on a case-by-case parameter basis, and optimal screening can only be achieved with the appropriate adjustments.

Fetal gender impact on multiple-marker screening results

Maternal serum alpha-fetoprotein (MSAFP), human chorionic gonadotropin (hCG), and unconjugated estriol (uE3) are used in combination with maternal age to calculate the risk for Down syndrome (DS) in pregnancy. Increased levels of hCG and decreased levels of MSAFP and uE3 are consistent with an increased risk for DS. We retrospectively evaluated second-trimester maternal serum marker levels in a large cohort of patients with known normal outcomes and documented fetal gender. These included 15,428 patients who had MSAFP measurements, 11,428 patients with both MSAFP and hCG, and 6,090 patients with all three markers including uE3. MSAFP levels in patients with female fetuses were consistently lower than those with males. Conversely, hCG was higher in pregnancies with females as compared to males. No gender-related difference was noted for uE3. These results would suggest that the computed DS risk for female fetuses is higher than for males, despite the fact that the incidence of DS is similar in both genders. This information could be useful for calculating gender-specific DS risk; however, this would require ultrasonographic determination of fetal sex.

Adhesion formation after intraperitoneal and extraperitoneal implantation of polypropylene mesh

Polypropylene mesh is commonly used in open and laparoscopic hernia repairs. We tested the hypothesis that intra-abdominal adhesion formation secondary to polypropylene mesh is greater when mesh is placed in an intraperitoneal versus an extraperitoneal position. Fifty adult male rats underwent midline laparotomy with or without implantation of a nonabsorbable mesh. There were ten rats in each of the following five groups: EP-M, creation of an extraperitoneal pocket without mesh placement; EP+M, mesh placement in an extraperitoneal pocket; IP+M, intraperitoneal mesh; IT-M, creation of an abdominal wall ischemic defect without mesh placement; IT+M, ischemic defect plus mesh. Adhesion formation was graded on a scale of 0 to 5, 2 weeks after operation. All groups formed adhesions. Tissue injury or the placement of a mesh in an intraperitoneal position resulted in significantly more adhesions. An entirely extraperitoneal approach to mesh placement is needed to minimize adhesions after laparoscopic hernia repair.

Combination of elevated maternal serum alpha-fetoprotein (MSAFP) and low estriol is highly predictive of anencephaly

Increased levels of second trimester maternal serum alpha-fetoprotein (MSAFP) have long been established as a marker for neural tube defects (NTDs). In addition, decreased levels of maternal estriol in the third trimester have been reported in pregnancies with anencephalic fetuses. The purpose of this study was to evaluate whether early second trimester unconjugated serum estriol (uE3) is an independent predictor of NTDs. The study included 57,031 patients who underwent maternal serum screening with MSAFP at 14-22 weeks gestation. Of these, 23,415 also had uE3 measurements. There were 63 cases of NTD, an overall incidence of 1.1 per 1,000. Elevated MSAFP (> or =2.5 MOM) was detected in 1,346 patients, 48 of which had NTDs. Decreased uE3 (< or =0.5) was detected in 1,437 patients, 17 of which had NTDs. The incidence of NTDs was significantly higher in patients with low uE3, compared to patients with normal/high uE3 (1.15% vs. 0.09%, P < 001). Finally, 51 patients had both increased MSAFP and decreased uE3; 16 of these had NTDs, 14 of which were anencephalics. In conclusion, both elevated MSAFP and low maternal serum estriol are predictive of NTD but have a low sensitivity. The combination of abnormally elevated MSAFP and low estriol is highly predictive of NTD in particular anencephaly.

Effect of adjustment of maternal serum alpha-fetoprotein levels in insulin-dependent diabetes mellitus

Our objective was to determine the effect of the 20% upward adjustment of maternal serum alphafetoprotein (MSAFP) in patients with insulin-dependent diabetes mellitus (IDDM) on the number of patients that would be classified at increased risk for pregnancy complicated by either Down syndrome (DS) or neural tube defect (NTD). We retrospectively evaluated a database containing 63,110 patients who underwent multiple serum marker screening between 14 and 22 weeks gestation; 620 patients with IDDM had measurements of MSAFP of which 479 also had measurements of beta-HCG, allowing calculation of DS risk. Increased NTD risk was defined as MSAFP >2.5 MOM while increased DS risk was defined as a calculated risk > or =1/270. One IDDM patient delivered an infant with a NTD; it was not detected on serum screening. No infants were born with DS. Of the 620 patients with MSAFP determinations, 9 had values >2.5 MOM before adjustment. After upward adjustment, 7 additional patients were identified. Sixteen patients were identified at increased risk for DS before and after adjustment. Our data suggest that the 20% upward adjustment of MSAFP increases by 78%, the number of patients who would require further evaluation for NTD's. Although we were able to identify 620 women with IDDM who underwent serum screening for NTD, the low prevalence of NTD's did not allow us to demonstrate an increased detection rate. The effect of upward adjustment of MSAFP on the number of patients categorized at increased DS risk appears to be minimal.

Maternal weight differences do not explain ethnic differences in biochemical screening

In previous work, we and others have shown that serum levels of alpha-fetoprotein, human chorionic gonadotropin, and estriol vary among the four commonly defined racial/ethnic groups seen in the United States: white, African-American, Asian, and Hispanic. We have suggested that better sensitivity and specificity could improve screening sensitivity and specificity. However, it has been argued that systematic weight differences among the groups could explain the variation. We evaluated the results from 208,257 patients having screening and found systematic weight differences. However, these differences were not as large as the racial/ethnic differences, showing that weight does not fully explain the discrepancy, and, therefore, four separate data bases give more accurate results.

Differential increases in AFP, hCG, and uE3 in twin pregnancies: impact on attempts to quantify Down syndrome screening calculations

Since the advent of multiple marker screening (MMS) for Down syndrome (DS) risk calculations, limitations for twins have been apparent. Recent attempts have been made to extrapolate mathematically singleton risks to twins. Here we investigate the pattern of levels among AFP, hCG, and uE3 in twins. MMS screening data from 4,443 twin pregnancies were compared to those from 258,885 singletons from 14-21 weeks of gestational age during a 3-year period (1992-1994) in our laboratory. Medians were determined for singletons and twins, and the ratios of twins to singletons were derived. Median AFP levels for twins are approximately double those of singletons, but median increases for hCG and uE3 are less than double. The data were divided further by ethnic groups (white, African American, Asian, and Hispanic), among which there were significant variations in medians, but not in the ratios of twins to singletons. The increased serum levels of different markers in twins are not consistent across analytes, possibly reflecting independent development of different compartments. Such differences mean that a mere mathematical conversion of singleton DS risks would be imbalanced among the analytes and cannot be applied reasonably to twins. Ethnic-specific databases are as important in twins as they are in singletons.

Precise gaussian distribution functions of maternal serum alpha-fetoprotein and free beta-subunit of human chorionic gonadotropin for trisomy 21 screening: improved accuracy for patient counseling

OBJECTIVE

Gaussian equation curves are used to generate baseline curves against which a priori maternal age Down syndrome risks are adjusted to develop likelihood ratios for individual patients. We sought to evaluate the accuracy of these calculations, minimize the affects of outliers, and to make improvements.

STUDY DESIGN

Gaussian distribution functions were used to investigate the best model for alpha-fetoprotein and free beta-human chorionic gonadotropin multiples of the median with use of nonlinear regressions. Parameters from distribution functions can be used to compute a more precise likelihood ratio for the decision logic for trisomy 21. A total of 58,297 normal cases and 348 cases of trisomy 21 were computed.

RESULTS

Log normal distribution functions generated by nonlinear regression produced excellent but exaggerated goodness of fit R2 to the frequency distributions of the data. For normal cases values were as follows (in mean, SD, and R2, respectively): log alpha-fetoprotein -0.07199, 0.15681, and 0.9970; log beta-human chorionic gonadotropin -0.15203, 0.24284, and 0.9987. For trisomy 21 cases the values were (in mean, SD, and R2, respectively) for log alpha-fetoprotein -0.19303, 0.15802, and 0.9828 and for log beta-human chorionic gonadotropin 0.19996, 0.29760, and 0.9669. Distributions reconstructed with use of statistical means and SDs generated goodness of fit R2 from 0.585 to 0.914. Use of means and SDs derived from distribution functions increased the R2 to 0.855 and 0.999. The change in the model produces, at a 5% false-positive rate, a sensitivity of 57.18% (199/348). A 1 in 113 cutoff point risk is obtained and is tighter than the 1 in 251 without the distribution functions, as versus 1 in 270 by age calculations alone.

CONCLUSIONS

Our data suggest that (1) normality of log transforms of alpha-fetoprotein and normality of log transforms of beta-human chorionic gonadotropin are reasonable models, (2) distribution functions can minimize the effect of outliers, which produces more realistic risk estimates, and (3) the effect of distribution functions versus standard mean and SDs cannot automatically be extrapolated to other parameters, which must be tested individually.

PKC zeta is a molecular switch in signal transduction of TNF-alpha, bifunctionally regulated by ceramide and arachidonic acid

Tumor necrosis factor (TNF-alpha) stimulates a number of signal transduction pathways in which phospholipases produce lipid second messengers. However, the immediate molecular targets of these messengers, in particular those of ceramide and arachidonic acid (AA) and their role in TNF signaling are not well defined. In this study we investigated the relationship of ceramide and AA in regulating an atypical PKC isozyme, PKC zeta. U937 cells responding to TNF-alpha treatment with NF kappa B activation displayed enhanced phosphorylation of PKC zeta, which is already detectable 30 s after stimulation. [14C]ceramide specifically binds to and regulates kinase activity of PKC zeta in a biphasic manner. Binding studies indicate high and low affinity binding with bmax values of 60 and 600 nM and Kd values of 7.5 and 320 nM respectively. At ceramide concentrations as low as 0.5 nM an up to 4-fold increase in autophosphorylation is obtained, which, at concentrations > 60 nM, again declines to basal levels. Interestingly, AA competes for ceramide binding and inhibits basal and ceramide-stimulated PKC zeta kinase activity at < 100 nM. Metabolism of [14C]ceramide in cells is slow and is inhibited in the presence of equimolar concentrations of lyso-phosphatidylcholine. Based on the bifunctional modulation of PKC zeta by the lipid messengers ceramide and AA, a model of TNF signal pathways is suggested in which PKC zeta takes a central position, acting as a molecular switch between mitogenic and growth inhibitory signals of TNF-alpha.

MOMs (multiples of the median) and DADs (discriminant aneuploidy detection): improved specificity and cost-effectiveness of biochemical screening for aneuploidy with DADs

OBJECTIVE

Our purpose was to assess the efficacy of double- and triple-screening paradigms for Down syndrome and to develop a more logical, statistical approach to risk prediction that will decrease the cost of screening and allow the incorporation of new parameters appropriately weighted for their contribution.

STUDY DESIGN

Data from 24,504 patients who had biochemical screening for Down syndrome by single (alpha-fetoprotein), double (alpha-fetoprotein, beta-human chorionic gonadotropin), or triple screening (alpha-fetoprotein, beta-human chorionic gonadotropin, unconjugated estriol) who had complete outcome information were analyzed by (1) existing gaussian-based methods, (2) the Glasgow ratio method, and (3) a new statistical approach (i.e., directly adjusted data sets for discriminant aneuploidy detection [DADs])

RESULTS

By use of individual risk-based thresholds for "at risk" status, both double and triple screening performed far better than single screening, but the percentages of patients at risk varied widely. When the percentages at risk were held constant, the sensitivity of double and triple screenings was similar, suggesting that there are no benefits of using estriol as a third marker. For 25,000 patients the use of only alpha-fetoprotein and beta-human chorionic gonadotropin would save about $500,000, with no decrease in sensitivity. With the DADs approach a statistically sound model giving more stable estimates was developed that permits each factor to be analyzed for its own explained proportion of variance and allows each parameter to have different weighting. For this data set the same sensitivity was seen with, conservatively, a 1% reduction in the percentage of patients at risk, which would reduce by 250 the number of amniocenteses, at a further savings of about $400,000.

CONCLUSIONS

By use of existing methods, double screening is equally as effective as triple screening, so that the expense of estriol is unnecessary. The DADs approach, by allowing for variable weighting of parameters, lowers the at risk percentage and will permit a much more flexible approach as new parameters become available. Changing to DADs and eliminating estriol should achieve higher specificity for the same sensitivity and save, conservatively, about $900,000 in this series. Extrapolated nationally, if confirmed, the annual savings could approach $72,000,000.

Assessment of the infectivity of corneal buttons taken from hepatitis B surface antigen seropositive donors

Sixty one corneas taken from 33 hepatitis B surface antigen (HBsAg) seropositive donors and 20 control corneas taken from 12 HBsAg seronegative donors were tested for the presence of HBsAg using reversed passive haemagglutination (RPHA) and enzyme linked immunosorbent assay (ELISA) and for the presence of hepatitis B virus core DNA (HBVcDNA) using the hybridisation technique in their epithelium, stroma endothelium, and storage media. HBsAg was detected by ELISA in the epithelium of one cornea (1.6%), in the stroma endothelial suspensions of six corneas (9.8%), and in the storage media of five corneas (8.2%). HBVcDNA was detected for the first time in the cornea; in the epithelium of four corneas (6.6%), stroma endothelium of nine corneas (14.8%), and the storage media of five corneas (8.2%). The control corneas were negative for HBsAg, while HBVcDNA was detected in the stroma endothelium of two corneas (10%) and in the media of two corneas (10%). This study confirmed that HBV can be present in the human cornea. Preservation in corneal storage media for up to 6 days could not eliminate the virus from the cornea. The possibility of HBV transmission through corneal transplantation should not be overlooked.