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Introduction: Follicular lymphoma is a common non-Hodgkin lymphoma that can start in a diverse array of tissues throughout the body. While the majority of patients may be able to live many years with this disease, cure remains very difficult to achieve., Objective: We sought to investigate the impact of follicular lymphoma primary disease site in early-stage disease on patient outcomes using a large national database., Methods: Baseline demographic and disease data for patients diagnosed with follicular lymphoma from 2000-2015 was identified and extracted from the NCI Surveillance, Epidemiology, and End Results (SEER) database. Primary disease sites were grouped into one of two cohorts: nodal disease (lymph nodes and spleen) and extranodal disease (everything else). Analysis was performed using summary statistics, Kaplan-Meier method, and Cox-proportional hazards models for univariate and multivariate analysis., Results: A total of 13,400 patients were included in the final analysis and the majority were non-Hispanic white (81%), with stage I (63%), and nodal FL (79%). Median overall survival for nodal disease was 15.1 years [95% CI (14.6-15.6)] while median overall survival for extranodal disease was 15.8 years [95% CI (14.9-16.3)]. Overall survival was slightly better for patients with extranodal disease [HR = 0.89, 95% CI (0.84-0.96); p-value = 0.00012]. This finding remained consistent after controlling for age and race [HR = 0.84, 95% CI (0.79-0.90); p-value <0.0001]., Conclusions: The primary site of involvement by early-stage follicular lymphoma may have an impact on patient outcomes and warrants further investigation., Competing Interests: Disclosure The authors have no conflicts of interest to disclose., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Substance misuse is common in patients undergoing limb reconstruction secondary to open fractures and fracture related infection. This group risk breaching the social contract with their treating team through reduced engagement with perioperative care. Potential problems include limited social support, intravenous access, analgesia and withdrawal. These factors may negatively influence the range of treatments offered to this group. We aimed to establish the prevalence and outcomes of the problematically non-concordant cohort in our limb reconstruction population, who we aim to treat equitably even where non-concordance is suspected pre-operatively. A retrospective study was performed using our prospectively collected free flap limb reconstruction database from December 2021-October 2023. Patient electronic health records were reviewed for demographics, perioperative details and outcomes. Eighty patients were identified, with 8 identified as problematically non-concordant (10%). All patients had a background of substance abuse; smoking (100%), alcohol (75%), IVDU (63%). Pre-operative non-concordance included absconding (43%), staff abuse (57%) and refusal of care (57%). Post-operative non-concordance included smoking (75%), mobilisation against instructions (75%), absconding (63%). No patients had free flap failure. Inpatient stay varied from 8-83 days, average 28.50% of patients did not attend follow-up. The expanding horizon of microsurgery means complex reconstruction is offered to a greater range of patients. Surgical teams should ensure that this service is offered equitably, individualising treatment plans to achieve the best outcomes. Risk of non-concordance is usually evident pre-operatively. We advise early involvement of substance misuse teams, discharge support and an understanding team to achieve good outcomes., Competing Interests: Conflict of Interest The authors have no conflicts of interest., (Crown Copyright © 2024. Published by Elsevier Ltd. All rights reserved.)

Background: Advances in treatment for patients with Diffuse Large B-Cell Lymphoma (DLBCL) have led to improved patient outcomes but the magnitude of these disparities remains understudied with regards to improved survival outcomes. We sought to describe changes in DLBCL survival trends over time and explore potential differential survival patterns by patients' race/ethnicity and age., Methods: We utilized the Surveillance, Epidemiology, and End Results (SEER) database to identify patients diagnosed with DLBCL from 1980 to 009 and determined 5-year survival outcomes for all patients, categorizing patients by year of diagnosis. We used descriptive statistics and logistic regression, adjusting for stage and year of diagnosis, to describe changes in 5-year survival rates over time by race/ethnicity and age., Results: We identified 43,564 patients with DLBCL eligible for this study. Median age was 67 years (ages: 18-64 = 44.2%, 65-79 = 37.1%, 80 + = 18.7%). Most patients were male (53.4%) and had advanced stage III/IV disease (40.0%). Most patients were White race (81.4%), followed by Asian/Pacific Islander (API) (6.3%), Black (6.3%), Hispanic (5.4%), and American Indian/Alaska Native (AIAN) (0.05%). Overall, the 5-year survival rate improved from 35.1% in 1980 to 52.4% in 2009 across all races and age groups (odds ratio [OR] for 5-year survival with increasing year of diagnosis = 1.05, P < .001). Patients in racial/ethnic minority groups (API: OR = 0.86, P < .0001; Black: OR = 0.57, P < .0001; AIAN: OR = 0.51, P = .008; Hispanic: 0.76, P = 0.291) and older adults (ages 65-79: OR = 0.43, P < .0001; ages 80+: OR = 0.13, P < .0001) had lower 5-year survival rates after adjusting for race, age, stage, and diagnosis year. We found consistent improvement in the odds of 5-year survival for year of diagnosis across all race and ethnicity groups (White: OR = 1.05, P < .001; API: OR = 1.04, P < .001; Black: OR = 1.06, p<.001; AIAN: OR = 1.05, P < .001; Hispanic: OR = 1.05, P < .005) and age groups (ages 18-64: OR = 1.06, P < .001; ages 65-79: OR = 1.04, P < .001; ages 80+: OR = 1.04, P < .001)., Conclusion: Patients with DLBCL experienced improvements in 5-year survival rates from 1980 to 2009, despite persistently lower survival among patients in racial/ethnic minority groups and older adults., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Background: Our previous studies showed that in ischemic and nonischemic heart failure (HF), the voltage-gated cardiac Na + channel α subunit (SCN5A) mRNA is abnormally spliced to produce two truncated transcript variants (E28C and D) that activate the unfolded protein response (UPR). We tested whether SCN5A post-transcriptional regulation was abnormal in hypertrophic cardiomyopathy (HCM)., Material and Methods: Human heart tissue was obtained from HCM patients. The changes in relative abundances of SCN5A, its variants, splicing factors RBM25 and LUC7A, and PERK, a major effector of the UPR, were analyzed by real time RT-PCR and the expression changes were confirmed by Western Blot., Results: We found reduced full-length transcript, increased SCN5A truncation variants and activation of UPR in HCM when compared to control hearts. In these patients, real time RT-PCR revealed that HCM patients had decreased SCN5A mRNA to 27.8±4.07% of control (P<0.01) and an increased abundance of E28C and E28D (3.4±0.3 and 2.8±0.3-fold, respectively, P<0.05). PERK mRNA increased 8.2±3.1 fold (P<0.01) in HCM patients. Western blot confirmed a significant increase of PERK., Conclusions: These data suggested that the full-length SCN5A was reduced in patients with HCM. This reduction was accompanied by abnormal SCN5A pre-mRNA splicing and UPR activation. These changes may contribute to the arrhythmic risk in HCM., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Rare kidney diseases encompass at least 150 different conditions, most of which are inherited. Although individual rare kidney diseases raise specific issues, as a group these rare diseases can have overlapping challenges in diagnosis and treatment. These challenges include small numbers of affected patients, unidentified causes of disease, lack of biomarkers for monitoring disease progression, and need for complex care. To address common clinical and patient issues among rare kidney diseases, the KDIGO Controversies Conference entitled, Common Elements in Rare Kidney Diseases, brought together a panel of multidisciplinary clinical providers and patient advocates to address five central issues for rare kidney diseases. These issues encompassed diagnostic challenges, management of kidney functional decline and progression of chronic kidney disease, challenges in clinical study design, translation of advances in research to clinical care, and provision of practical and integrated patient support. Thus, by a process of consensus, guidance for addressing these challenges was developed and is presented here., (Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.)

Exposure of coal waste rock to atmospheric oxygen can result in the oxidation of sulfide minerals and the release of sulfate (SO 4 ) and associated trace elements (e.g., Se, As, Cd, and Zn) to groundwaters and surface waters. Similarly, reduced iron minerals such as siderite, ankerite, and the sulfide, pyrite, present in the waste rock can also undergo oxidation, resulting in the formation of iron oxyhydroxides that can adsorb trace elements released from the oxidation of the sulfide minerals. Characterization and quantification of the distribution of sulfide and iron minerals, their oxidation products, as well as leaching rates are critical to assessing present-day and future impacts of SO 2- and associated trace elements on receiving waters. Synchrotron-based X-ray absorption near edge spectroscopic analysis of coal waste rock samples from the Elk Valley, British Columbia showed Fe present as pyrite (mean 6.0%), siderite (mean 44.3%), goethite (mean 35.4%), and lepidocrocite (mean 14.3%) with S present as sulfide (mean 26.9%), organic S (mean 58.7%), and SO 4 2- . Geochemical modeling showed the porewaters in the dumps to be supersaturated with respect to Fe oxyhydroxides and undersaturated with respect to gypsum, consistent with solids analyses. Coupling Fe and S mineralogical data with long-term water quality and quantity measurements from the base of one dump suggest about 10% of the sulfides (which represent 2% of total S) in the dump were oxidized over the past 30years. The S from these oxidized sulfides was released to the receiving surface water as SO 4 2- (mean 14.4%). Squeezed porewater samples from dump solids yielded mean concentrations of 0.28mg/L Fe and 1246mg/L SO 4 2- . Geochemical modeling showed the porewaters in the dumps to be supersaturated with respect to Fe oxyhydroxides and undersaturated with respect to gypsum, consistent with solids analyses. Coupling Fe and S mineralogical data with long-term water quality and quantity measurements from the base of one dump suggest about 10% of the sulfides (which represent 2% of total S) in the dump were oxidized over the past 30years. The S from these oxidized sulfides was released to the receiving surface water as SO 4 2- and the majority of the Fe precipitated as secondary Fe oxyhydroxides (only 3.0×10 -5 % of the Fe was released to the receiving waters over the past 30years). Although the data suggest that the leaching of SO 4 2- from the waste rock dump could continue for about 300years, assuming no change in the rate of oxidation of sulfides, SO 4 2- is currently not a concern in receiving surface waters as the concentration levels are below regulatory limits., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Slowing of progression and inducing the regression of atherosclerosis with medical therapy have been shown to be associated with an extensive reduction in risk of cardiovascular events. This proof of concept was obtained with invasive angiographic studies but these are, for obvious reasons, impractical for sequential investigations. Non-invasive imaging has henceforth replaced the more cumbersome invasive studies and has proven extremely valuable in numerous occasions. Because of excellent reproducibility and no radiation exposure, magnetic resonance imaging (MRI) has become the non-invasive method of choice to assess the efficacy of anti-atherosclerotic drugs. The high accuracy of this technology is particularly helpful in rare diseases where the small number of affected patients makes the conduct of outcome-trials in large cohorts impractical. With MRI it is possible to assess the extent, as well as the composition, of atherosclerotic plaques and this further enhances the utility of this technology., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Background: Experimental modeling of arteriovenous hemodialysis fistula (AVF) hemodynamics is challenging. Mathematical modeling struggles to accurately represent the capillary bed and venous circulation. In vivo animal models are expensive and labor intensive. We hypothesized that an in vitro, physiologic model of the extremity arteriovenous circulation with provisions for AVF and distal revascularization and interval ligation (DRIL) configurations could be created as a platform for hemodynamic modeling and testing., Methods: An anatomic, upper extremity arteriovenous model was constructed of tubing focusing on the circulation from the subclavian artery to subclavian vein. Tubing material, length, diameter, and wall thickness were selected to match vessel compliance and morphology. All branch points were constructed at physiologic angles. The venous system and capillary bed were modeled using tubing and one-way valves and compliance chambers. A glycerin/water solution was created to match blood viscosity. The system was connected to a heart simulator. Pressure waveforms and flows were recorded at multiple sites along the model for the native circulation, brachiocephalic AVF configuration, and the AVF with DR without and with IL (DR no IL and DRIL)., Results: A preset mean cardiac output of 4.2 L/min from the heart simulator yielded a subclavian artery pressure of 125/55 mm Hg and a brachial artery pressure of 121/54 mm Hg with physiologic arterial waveforms. Mean capillary bed perfusion pressure was 41 mm Hg, and mean venous pressure in the distal brachial vein was 17 mm Hg with physiologic waveforms. AVF configuration resulted in a 15% decrease in distal pressure and a 65% decrease in distal flow to the hand. DR no IL had no change in distal pressure with a 27% increase in distal flow. DRIL resulted in a 3% increase in distal pressure and a 15% increase in distal flow to the hand above that of DR no IL. Flow through the DR bypass decreased from 329 mL/min to 55 mL/min with the addition of IL. Flow through the AVF for both DR no IL and DRIL was preserved., Conclusions: Through the construction and validation of an in vitro, pulsatile arteriovenous model, the intricate hemodynamics of AVF and treatments for ischemic steal can be studied. DR with or without IL improved distal blood flow in addition to preserving AVF flow. IL decreased the blood flow through the DR bypass itself. The findings of the AVF as a pressure sink and the relative role of IL with DR bypass has allowed this model to provide hemodynamic insight difficult or impossible to obtain in animal or human models. Further study of these phenomena with this model should allow for more effective AVF placement and maturation while personalizing treatment for associated ischemic steal., Clinical Relevance: The complications of arteriovenous fistula (AVF)-associated steal with its concurrent surgical treatments have been clinically described but have relatively little published, concrete hemodynamic data. A further understanding of the underlying hemodynamics is necessary to prevent the occurrence of steal and improve treatment when it occurs. Specific objectives are to study the blood flow through an AVF with varying anatomic and physiologic parameters, determine what factors contribute to the development of arterial steal distal to an AVF, and create optimal interventions to treat arterial steal from an AVF when it occurs. The long-term goal is creation of AVF tailored to patient-specific parameters, resulting in higher rates of functional fistulas with decreases in fistula-related complications. The ability to study fluid dynamics using a unique, in vitro, upper extremity pulsatile arteriovenous circulation simulator creates the ideal platform for this work., (Copyright © 2014 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Introduction: Covalent protein binding of metabolically reactive intermediates of drugs has been implicated in drug toxicity including the occurrence of idiosyncratic drug toxicity. Investigators therefore would prefer to avoid developing compounds that produce significant amounts of reactive metabolites. By incubating the radiolabeled drug of interest with liver microsomes it is possible to evaluate the propensity of a drug candidate to covalently bind to proteins., Methods: Here we present a semi-automated method in which a Brandel cell harvester is used to collect and wash proteins that have been incubated with radiolabeled drug. This method utilizes glass fiber filter paper to capture precipitated protein, rather than the more traditional exhaustive extraction/centrifugation approach. Using model compounds (including [14C]diclofenac, [3H]imipramine, [14C]naphthalene, and [14C]L-746530) we compare the covalent binding results obtained using this method to results generated using the traditional method and we performed cross-laboratory testing of assay reproducibility., Results: It was found that results from new method correlated highly with the traditional method (R2=0.89). The cross-laboratory testing of the method showed an average interlaboratory coefficient of variation of only 18.4%., Discussion: This method provides comparable results to the more traditional centrifugation-based method with considerable time and labor savings.

Blood alcohol measurements determined by headspace gas chromatography have been challenged on the grounds that the presence of the preservative sodium fluoride in blood samples artificially increases headspace alcohol concentrations due to a salting out effect. Blood samples containing varying amounts of ethanol and sodium fluoride were tested using semi-automated headspace gas chromatography with n-propyl alcohol as the internal standard to assess the validity of this challenge. We find, in fact, that under these test conditions the measured alcohol levels are systematically depressed as the amount of sodium fluoride in the blood sample increases. The challenge thus has no basis.

The prevalence of multiple sclerosis (MS) in Newcastle, Australia increased significantly between 1961 and 1981 and the incidence of the disease also increased between the decades 1950-1959 and 1971-1981. The present study sought to determine whether there has been a further increase in the frequency of MS in the subsequent 15 years, and to examine the potential factors underlying this change. The incidence, prevalence and clinical profile of multiple sclerosis were therefore re-examined in Newcastle, Australia in 1996 using comparable diagnostic criteria and methods to those employed in studies in the same region in 1961 and 1981. There has been a significant progressive increase in prevalence from 19.6 to 59.1 per 100,000 population and a significant increase in incidence from 1.2 to 2.4 per 100,000 population from 1961 to 1996. The most pronounced increase in prevalence was in females and in the age-group over 60 years, and there was also an increased incidence in females aged 20-29 years. There was little change in the age of disease onset, but duration of disease in females had increased substantially. The significant increase in prevalence is attributed to increased incidence, particularly in females; and to increased survival. Although such trends in prevalence have been observed in the Northern Hemisphere, this is the first such study in the Southern Hemisphere to show a longitudinal increase in prevalence and incidence over a period of this duration.

Lipoprotein particles (Lps) in normal human cerebrospinal fluid (CSF) are distinct from those found in plasma and include unique apolipoprotein E (apoE indicates protein; APOE, gene) containing lipoproteins rarely seen in human plasma. Less favourable neurological recovery after subarachnoid hemorrhage (SAH) has been observed in patients who possess the APOE epsilon4 allele raising the possibility that apoE influences neuronal survival after brain injury. We analysed Lps from control and SAH CSF testing the hypotheses that following brain injury CSF Lps undergo remodelling and apoE containing Lps are selectively depleted from brain injury CSF. Lipoproteins were fractionated using CSF from six control pools and six patients with SAH on a sepharose 6HR 10/30 size exclusion column. Fractions were assayed for total cholesterol (TC), free cholesterol (FC), phospholipid, triglyceride (TG), apoE, apolipoprotein B (apoB), and apolipoprotein AI (apoAI). Compared to control CSF there were significant (P<0.05) increases in TC, FC, TG, and apoAI in SAH CSF. Plasma sized apoB-containing lipoproteins and a very small apoAI-containing Lps were identified in the SAH CSF, which were not present in controls. However, despite the release of plasma lipoproteins into the subarachnoid space, there was no significant increase in CSF apoE. These data provide novel indirect evidence suggesting that after SAH CSF Lps undergo remodelling and apoE containing Lps are selectively reduced in brain injury CSF. The remodelling of CSF Lps and selective reduction of apoE containing lipoproteins may reflect an important response of the human brain to injury.

Background: Immunological and clinical effects of post-transplant growth factor administration have not been well studied. This report describes the outcome and immune functions of a total of 50 HLA-matched related donor allogeneic blood stem-cell transplantation patients who received post-transplant G-CSF (10 microg/kg) or placebo., Methods: Immune status, including number of lymphocyte subsets and their functions, and serum immunoglobulin levels and clinical status--including GvHD, rate of relapse, event-free survival, and overall survival--were determined in the patients enrolled in this study., Results: Twenty-eight patients survived 1 year after transplant, and 15 patients had available results to compare immune function by randomization assignment. At 12 months post-transplant, immune parameters in G-CSF versus placebo groups showed no statistically significant differences in number of circulating lymphocyte subsets CD3, CD4, CD8, CD19 and CD56 in the two groups. There was no significant (NS) difference in immunoglobulin IgG, IgA and IgM levels, NK or LAK cell-mediated cytotoxicity levels, and mitogen-induced proliferation between post-transplant G-CSF and placebo group. In addition, the analyses of immune parameters at earlier time-points on Days 28, 100, 180, and 270 revealed that, except for LAK cytotoxicity at Day 100, there was no differences between the two groups. Fourteen of 26 patients are alive in the G-CSF arm and nine of 24 in the placebo arm. Median follow-up of surviving patients is 43 months. Four year overall and event-free survival in the G-CSF and the placebo group were 53% and 35% (NS), and 44% and 36% (NS) respectively. Bacterial or fungal infections were the cause of six of 12 deaths in the G-CSF arm (all bacterial) and of four of 15 deaths in the placebo arm (two deaths from Aspergillus) (P=0.26). Two patients relapsed in the G-CSF arm and three in the placebo arm. Four year cumulative incidences of relapse were 8% versus 13% in G-CSF versus placebo arms, respectively, (NS). Chronic GvHD developed in 14 of 19 100-day survivors after G-CSF (11 extensive stage), and in 17 of 20 (14 extensive stage) in the placebo arm. The 4-year cumulative incidence of chronic GvHD was 56% [95% confidence interval (CI) 24-88%] after G-CSF and 71% (95% CI 48-94%) after placebo; this difference was not statistically significant (log rank P=0.41)., Conclusion: In summary, there were no significant immunological or alterations in clinical benefit of post-transplant G-CSF administration in T-replete allotransplant recipients.

Plasminogen (PLG) exists in the circulation as two glycoforms, I and II. Angiostatin (AST) is a polypeptide that has been cleaved from the kringle region of PLG and has strong anti-angiogenic properties. AST-I and AST-II, which consisted only of kringles 1 through 3, were prepared by the action of urokinase on purified rabbit PLG-I and PLG-II, respectively, in the presence of N-acetyl cysteine, followed by affinity chromatography on lysine-Sepharose. Purified AST-I and AST-II were tested for functional activity with a chick chorioallantoic membrane (CAM) model; when similar amounts were applied to a 6-day CAM, AST-I was substantially more effective than AST-II in decreasing vascular supply to the CAM over a 72-hour period; this activity correlated with a loss of capillaries, probably through apoptosis of endothelial cells. Radiolabeled AST-I and AST-II (iodine 125 and iodine 131) were co-injected intravenously into healthy rabbits to determine their clearances from plasma measured over 3 days. Over a dose range of 0.08 to 2.7 microg/kg, the fractional catabolic rate within the intravascular space (j(3)) indicated that AST-I was cleared 3-fold to 4-fold more rapidly than AST-II (P < .001). The catabolic half-life of AST-I (2.01 +/- 0.19 days) was significantly less than that of AST-II (2.62 +/- 0.20 days). The faster clearance of AST-I from the intravascular space was matched by its more rapid passage than AST-II to the extravascular space of various organs over 60 minutes in vivo. This property of AST-I as compared with AST-II may partially explain its greater anti-angiogenic potential. From the plasma concentrations of PLG-I and PLG-II and their relative behaviors toward rabbit VX-2 lung tumors in vivo, we predict that substantially greater quantities of AST-II than AST-I may be released into the extravascular space of tumors.

Background: Gonorrhoea is a common infectious disease, poorly controlled despite effective treatments. Tracing chains of transmission is difficult, because sexual partners are commonly difficult or impossible to identify. We assess the use of gonococcal opa-typing in identifying transmission links not revealed through interview., Methods: Epidemiological data and gonococcal isolates were collected prospectively from patients at two UK clinics in London and Sheffield. Social and epidemiological data were combined with molecular typing of gonococcal isolates by a new methodology based on the polymorphisms of the opa gene., Findings: In London, interview data and opa-typing on samples from 215 cases showed a diverse population with few links. In Sheffield, interview data identified links between 51 (43%) of 120 cases, whereas opa-typing suggested a more connected population: 95 (79%) of cases had shared profiles. There was a highly significant correlation between the two distributions with epidemiological clusters appearing as a subset of the opa clusters. Two large opa clusters, of 18 and 43 cases, accounted for 50% of local cases of gonorrhoea. Discordance between epidemiological and opa-typing data was observed at highly connected points in the sexual network., Interpretation: Opa-typing is a more powerful tool for epidemiological investigation of gonorrhoea transmission than earlier methods. Opa-typing can link infections that would otherwise remain unlinked, and may aid interventions to control endemic disease.

The comparisons of treatments in randomized clinical trials may use the analysis of covariance to adjust for patient characteristics. We present theoretical results that describe when such an adjustment would be expected to be beneficial. A distinction is made between covariates that are balanced in the design and those that are assigned by the randomization process. The results support the commonly held view that features balanced in the design of the trial (e.g., by stratification) and those that are strongly predictive of the outcome, and thus considered clinically prognostic, should normally be included in the analysis. For other covariates that are not balanced in the design, the potential benefits of including them in the analysis will depend on the number of patients in the trial. However, there is frequently a set of variables whose relevance is unknown and for which data-dependent methods of selection, based on the data for the current trial, have been proposed. A review of the literature has shown that these methods can produce misleading inferences. The decision as to which covariates to include in the analysis should be specified in the protocol on the basis of data from previous trials on similar patient populations. The methods are illustrated with data from a trial comparing two therapies for treating scalp psoriasis where the clinical importance of patients' age and sex as prognostic factors for efficacy is unknown. We show for what size of future trials it would be beneficial to adjust for these covariates and for what size trials it would not. In all cases, prespecification of variables to be included in the analysis is essential in order to avoid bias.

Background: Cardiopulmonary bypass is associated with impaired platelet macroaggregation. Heparin contributes to platelet dysfunction before extracorporeal circulation. In vitro heparinization of whole blood does not impair macroaggregation. Heparin releases several endothelial proteins; thus heparin may inhibit macroaggregation indirectly., Methods: Patients undergoing operations using cardiopulmonary bypass and ABO blood group compatible volunteers were studied. Whole blood impedance aggregometry assessed macroaggregation in response to collagen (0.6 microg ml(-1)) in blood diluted either with normal saline or with platelet poor plasma, obtained from patients at different stages of cardiopulmonary bypass., Results: Before heparinization, blood diluted with its own platelet poor plasma recorded an impedance change of 13.0 (4.7 to 15.6) Ohms. Platelet poor plasma obtained after heparinization or during extracorporeal circulation reduced this response to 3.7 (1.1 to 8.4) and 2.0 (1.1 to 3.3) Ohms, respectively (both p < 0.0001 versus pre-heparin; n = 13). Macroaggregation in blood from volunteers was similarly inhibited by patients' platelet poor plasma (n = 30). The macroaggregatory response in blood sampled after heparinization for cardiopulmonary bypass, decreased gradually from 11.4 (8.2 to 15.9) Ohms immediately after sampling to 1.7 (1.4 to 4.1) Ohms 2 hours later (p < 0.0001; n = 11)., Conclusions: In vivo heparinization induces plasma changes that inhibit platelet macroaggregation. This is an indirect, delayed inhibition that is transferable in vitro to normal platelets.

Data on the prevalence and severity of dental caries collected by country members of the Pan American Health Organisation (PAHO) were summarised to analyse current status and trends since the 1970s. The mean number of decayed, missing, and filled teeth (DMF-T) among 12-year-old children and the relative contribution of each DMF-T component were collected from official reports and publications in the scientific literature. Overall, a secular trend toward lower caries prevalence was observed in most countries, more notably among those with large prevention programmes using fluorides. Many countries have reached the World Health Organization (WHO) year 2000 goal of a mean DMF-T of < or = 3 but others are still far from reaching that goal. Few countries have reached the status of having large proportions of disease prevalence localised in a small percentage of the population, a pattern observed as prevalence decreases. Since 1994, PAHO's Regional Oral Health Program has developed two strategies to address these issues: the introduction and reinforcement of national preventive programmes using fluorides and the introduction of the atraumatic restorative treatment (ART).

In the rabbit blood stream, plasminogen circulates as two glycoforms, plasminogen I (PLG-I) and plasminogen II (PLG-II), in a molar ratio of 1:2.2. To compare their relative behaviors toward a site of vascular injury, radiolabeled samples of PLG-I and PLG-II were coinjected intravenously into NZW rabbits before inducing a de-endothelializing (balloon catheter) injury to the thoracic aorta. At various times (5 to 60 minutes) after injury, each rabbit was anesthetized and exsanguinated, the aorta was excised, and the radioactivity per centimeters squared of aortic intima-media (IM) was measured relative to that of blood at exsanguination. The uptake of iodine 125-labeled PLG-I and iodine 131-labeled PLG-II showed that the IM was essentially saturated by both glycoforms by 30 to 40 minutes after injury. Extrapolation of the flux rates to 1 minute after injury indicated that the uptake of PLG-II (2.4 pmol/min/cm2) exceeded PLG-I (0.5 pmol/min/cm2) almost five-fold. This result is consistent with an earlier report (Metabolism 1994;43:1430-7) that PLG-II is released by the liver and catabolized in vivo approximately five times faster than PLG-I. By molar comparison, the flux of total plasminogen (ie, PLG-I plus PLG-II) into the injured aorta wall in vivo was 2.4 times greater than that for prothrombin. Assuming both zymogens are converted to their respective proteases within the wound site, then approximately 2 to 3 molecules of plasmin are released for each molecule of thrombin in vivo. The possible significance of this plasmin:thrombin ratio is discussed in respect to the turnover of fibrin(ogen) within the site of vascular injury.

2,4-dichlorophenoxyacetic acid and its derivatives (collectively known as 2,4-D) are herbicides used to control a wide variety of broadleaf and woody plants. The genetic toxicity of an ester (2,4-D 2-butoxyethylester) and two salts (2,4-D isopropylamine and 2,4-D triisopropanolamine) was investigated in cultured mammalian cells. The end points used were the induction of chromosomal aberrations in primary cultures of rat lymphocytes and forward mutations at the HGPRT locus of Chinese hamster ovary cells. There was no evidence of genotoxicity for the test materials in the experimental systems used. These results were consistent with the general lack of genotoxic potential for 2,4-D in a number of other test systems.

Our laboratory has been routinely using suspended and cultured human hepatocytes for predicting drug metabolism and enzyme induction by drug candidates to aid drug discovery. Increasing limitation and irregular availability of human tissue has indicated the need for maximizing the use of this valuable resource. Cryopreservation of surplus hepatocytes after isolation would greatly increase the potential of this model. However, cryopreservation of hepatocytes by various methods has resulted in cells with poor metabolic activity and unacceptably low survival rates in culture. Recently, Zaleski et al. (Biochem. Pharmacol. 46 (1993) 111-116) reported that cryopreserved rat hepatocytes retained metabolic capacity similar to fresh hepatocytes when the cells were preincubated for 30 min at 37 degrees C in Krebs Ringer bicarbonate buffer prior to freezing. To further explore this methodology, both the functional capacity of the cells in culture as well as their ability to retain CYP inducibility were investigated with thawed cryopreserved hepatocytes. Although human hepatocytes were used in this study the initial work focused on rat hepatocytes as a cell model. Our results showed that while the preincubation step did not appear to effect the initial viability of cryopreserved hepatocytes, survival of the cells in culture was greatly enhanced. Plating efficiencies for nonpreincubated cryopreserved hepatocytes were decreased to approximately 15% of fresh cells after 48 h in culture. In contrast, cells that had been preincubated prior to freezing had an excellent plating efficiency (approximately 60%) and responded to classical CYP inducers dexamethasone, beta-naphthoflavone and phenobarbital in a manner indistinguishable from that of fresh hepatocytes. Experiments with human hepatocytes have also demonstrated similar results. This is the first time to our knowledge that cryopreserved hepatocytes from both rat and human have been shown to reproducibly respond to CYP inducers in culture.

The cryopreservation of human liver slices is a promising way to enhance the ability to test the metabolism of drug candidates. This study demonstrates the use of a novel technique for the cryopreservation of both rat and human liver slices. In this technique the slices are treated with Me2SO and sandwiched between aluminum plates separated by a thin gasket. The device is then submerged in liquid nitrogen to freeze the slices, which can then be stored until use. To thaw the slices, the apparatus is submerged in a water bath at 37 degrees C. Slices frozen and thawed in this manner were compared to those frozen in conventional cryovials. The viability of the slices was determined by incubating them in 12-well plates and measuring urea synthesis, ethoxycoumarin metabolism, and cytosolic enzyme leakage (LDH and ALT). The viability of rat slices frozen between plates approached that of fresh slices and was consistently higher than slices frozen in cryovials. Slices from two human samples gave similar results. The technique was found to work over a wide range of Me2SO concentrations (4.5 to 22% was tested) with an optimal concentration between 10 and 15%., (Copyright 1999 Academic Press.)

Here we report 658 expressed sequence tags (ESTs) generated from the 5'-termini of clones randomly selected from directional cDNA libraries constructed from mRNAs from three developmental stages of Schistosoma japonicum. Putative identifications were assigned to 46. 2% of the ESTs; 6.4% were previously known from S. japonicum, 5.6% were previously known from S. mansoni, 34.2% were known from other organisms, and the remaining 53.8% may represent S. japonicum-specific genes. These 658 ESTs appeared to be derived from 457 unique genes, which together represent 2 to 3% of the 15,000 to 20,000 genes predicted to occur in the schistosome genome., (Copyright 1998 Academic Press.)

We challenge the notion that double data entry is either sufficient or necessary to ensure good-quality data in clinical trials. Although we do not completely reject that notion, we quantify some of the effects that poor quality data have on final study results in terms of estimation, significance testing, and power. By introducing digit errors into simulated blood pressure measurements we demonstrate that simple range checks allow us to detect (and therefore correct) the main errors that impact the final study results and conclusions. The errors that cannot easily be detected by such range checks, although possibly numerous, are shown to be of little importance in drawing the correct conclusions from the statistical analysis of data. Exploratory data analysis cannot identify all errors that a second data entry would detect, but on the other hand, not all errors that are found by exploratory data analysis are detectable by double data entry. Double data entry is concerned solely with ensuring, to a high degree of certainty, that what is recorded on the case record form is transcribed into the database. Exploratory data analysis looks beyond the case record form to challenge the plausibility of the written data. In this sense, the second entering of data has some benefit, but the use of exploratory data analysis methods, either as data entry is ongoing or at the end of data entry and as the first stage in an analysis strategy, should always be mandatory.

Background: Trachoma is a leading cause of blindness in the developing world and is most prevalent among people who live in poor rural communities in arid locations., Methods: We analysed the results of surveys of trachoma prevalence in Marakissa, a rural village in The Gambia. These surveys were undertaken in 1959, by the Medical Research Council, and in 1987 and 1996 by the Gambian National Eye Care Programme., Findings: During this 37-year period, the prevalence of active inflammatory trachoma among children aged 0-9 years fell from 65.7 cases per 100 children in 1959 to 2.4 cases per 100 children in 1996. The prevalence also fell dramatically among people of 10-19 years (52.5 to 1.4 per 100) and among people of 20 years and older (36.7 to 0 cases per 100)., Interpretation: The dramatic fall in disease occurrence was paralleled by improvements in sanitation, water supply, education, and access to health care in the village. Of particular importance is that the decline in trachoma occurred without any trachoma-specific intervention.

Adult Schistosoma japonicum parasites synthesize and secrete both cathepsin L and cathepsin B cysteine proteinases. The specific activities of cathepsin L were many-fold higher than that of cathepsin B. The cDNAs encoding two distinct cathepsin L proteinases, here termed cathepsin L1 and L2, were isolated. The deduced amino acid sequences of the mature cathepsin L1 and L2 were approximately 41% identical, and moreover, S. japonicum cathepsin L2 showed more similarity with human cathepsin L than with schistosome cathepsin L1. Schistosome cathepsin L proteinases may be involved in the digestion of hemoglobin obtained from host erythrocytes. However, since we detected their presence in schistosome eggs, the release of these enzymes by eggs trapped in the liver and other organs may be associated with the granulomatous responses which characterize the pathology of human schistosomiasis.

Twenty obese women were randomly assigned to consume (for 16 wk) either a 420-kcal/d liquid diet (n = 12) or a 1200-kcal/d balanced diet (n = 8). Thereafter, patients in both conditions were prescribed a 1200-kcal/d diet for the remainder of treatment (week 45). Six obese nondieters served as control subjects. Ambulatory electrocardiographic (Holter) monitor readings were obtained on all patients at baseline and weeks 3, 9, 13, 17, 19, and 45 of the study and were analyzed for ventricular premature depolarizations (VPDs) per hour, paired forms, and runs of ventricular tachycardia. There were no statistically significant changes in VPDs in any condition during treatment. Similarly, there were no significant changes in the PR, QRS, and corrected QT intervals. The results indicate that under appropriate medical supervision, very-low-calorie diets can be used safely for up to 16 wk by significantly obese patients free of pre-existing cardiac disease.

The RNA genome of hepatitis A virus (HAV) contains a lengthy and relatively well conserved 5' nontranslated region (5'NTR). In other picornaviruses, the 5'NTR has been shown to have important functions related to the initiation of viral translation and replication of viral RNA, functions which are critically dependent on both primary and secondary RNA structure. We have utilized a phylogenetic approach to construct a model of the secondary structure of the HAV 5'NTR. By comparing the nucleotide sequences of genetically divergent simian and human HAV strains, we identified a series of covariant nucleotide substitutions which are predictive of conserved, double-stranded helical structures within the 5'NTR, and which thus permitted improved thermodynamic modeling of the secondary structure. The model was further refined based on the observed sites of cleavage of synthetic RNA by single- and double-strand specific RNAses. The results of these studies suggest that the 5'NTR of HAV has a general organization similar to that of other picornaviruses, and shares certain structural features and perhaps specific functions with the 5'NTRs of the cardioviruses and aphthoviruses.

Leukaemic infiltration of the anterior chamber of the eye was the only sign of relapse in two children with acute lymphoblastic leukaemia who had been off treatment for two and four months. The malignant cells had probably been present in the eye since the onset of the disease.

Fifty-four healthy patients and 21 patients with chronic renal disease received either suxamethonium 100 mg or suxethonium 150 mg for neuromuscular blockade during endotracheal intubation. A significant increase in plasma potassium concentration was observed following the administration of suxamethonium. No increase occurred in patients who received suxethonium. It is concluded that suxethonium may be preferable to suxamethonium in patients who are at risk from an increase in the plasma potassium concentration.

This study investigated the acceptability of two very-low-calorie diets in 16 moderately overweight persons participating in a weight reduction program. Subjects were prescribed a 1000-1200 kcal balanced diet the first month and asked to complete appetite and mood scales on a weekly basis. They were then randomly assigned to either a protein-sparing-modified fast (PSMF) or a protein-formula-liquid diet, each of which provided about 400 kcal daily. Analysis of the appetite data showed that PSMF subjects reported significantly less hunger and preoccupation with eating than did liquid diet subjects during 2 of the 4 weeks on a very-low-calorie diet. Subjects in both conditions reported significant reductions in anxiety. Results are discussed in terms of possible advantages of PSMF.

Analysis of 422 patients with clinical diagnoses of motoneurone disease (MND), multiple sclerosis, cervical spondylosis with myelopathy, or stroke, from two referral centres, suggested a simple four-step algorithm for diagnosing MND. The algorithm provided a 98% sensitivity (true positive diagnosis) and 86% specificity, and therefore gives a baseline for diagnostic criteria suitable for use in clinical research of MND.

Refractive errors were determined photographically in a group of infants and children and were compared to conventional cycloplegic retinoscopy. The refractor consisted of a mirror telephoto lens and strobe flash designed to mimic the action of a retinoscope. Significant amblyogenic conditions such as anisometropia and high isoametropia were detectable. Strabismus and media opacities were also recordable. The technique provides a potential mass suited for infants.

204 of 460 patients with upper gastrointestinal bleeding admitted to a busy district hospital were found to be bleeding from peptic ulcers or to have signs of recent haemorrhage at endoscopy within 24 h of admission. To determine if the small bipolar probe could stop bleeding or rebleeding, patients were allocated to electrocoagulation (101) or not (103); other aspects of treatment were identical. Groups were stratified by ulcer site to give similar numbers in each. To allow for differences in sex, age, initial haemoglobin, presence of other diseases, and shock, data were analysed by logistic regression. Fewer patients in the treated group (17) continued to bleed or rebled compared with controls (34). Rebleeding and mortality rates in the treated group were higher early in the trial, suggesting the need for experience in application of the probe. Further improvements in technology and technique may result in significant reductions in mortality.

We have compared, in 60 adult patients, the cardiovascular effects of glycopyrronium 5 micrograms kg-1 and 10 micrograms kg-1 given either simultaneously or 1 min before edrophonium 1 mg kg-1. Significant differences between the four groups were detected (P less than 0.001). Both groups receiving 10 micrograms kg-1 showed increases in heart rate of up to 30 beat min-1 (95% confidence limits 28-32 beat min-1). Use of glycopyrronium 5 micrograms kg-1 provided greater cardiovascular stability and, given 1 min before the edrophonium, was sufficient to minimize early, edrophonium-induced bradycardias. This low dose of glycopyrronium provided good control of oropharyngeal secretions.

A monoclonal antibody (I8B/A5) was generated towards human first-trimester purified trophoblast plasma membrane which, unlike others reported in the literature, reacted only against cytotrophoblast but not against syncytiotrophoblast. However, this antibody cross-reacted with certain fetal epithelial and endothelial surfaces in a well-defined manner. On such stratified epithelium as fetal skin, only the basal layers of cells were stained, and this was therefore analogous to the pattern observed in chorionic villi where only underlying cytotrophoblast and not superficial syncytiotrophoblast reacted with I8B/A5. These observations suggest that the target antigen either could be a component of certain structures at these sites, such as basement membrane, or it is a marker for proliferating and undifferentiated cells, which would make it an interesting molecule for developmental biologists.