Erratum to "Reproductive performance of early- and late-calving dairy cows artificially inseminated after ovulation synchronization and estrous resynchronization or artificially inseminated after observed estrus" (JDS Commun. 2:80-85)

[This corrects the article DOI: 10.3168/jdsc.2020-0035.].

Securing access to personnel and materials in transboundary animal disease responses

A lack of human and material resources can limit effective responses to animal disease emergencies. Drawing upon examples from Australia and New Zealand, this paper proposes a framework for identifying human and material resources and securing the necessary personnel and materials before or during an animal disease emergency. This staged process involves: a) assessing the nature of the risks to be managed, b) identifying the types of resources required, c) assessing available resources and identifying gaps and d) developing arrangements to ensure availability of resources. It discusses the advantages and disadvantages of different strategies to secure access to human and material resources, including whole-of-government arrangements to access other government resources, national and international reserve models for responders, just-in-time employment and purchase of materials, and purchase of stockpiles.

Use of affinity analysis to guide habitat restoration and enhancement for the imperiled delta smelt

Habitat restoration efforts in the upper San Francisco Estuary, including the Sacramento-San Joaquin Delta, California, move forward, despite a paucity of information on the environmental requirements of many targeted species. The endemic delta smelt Hypomesus transpacificus, protected under the federal Endangered Species Act, is a primary focus of those efforts despite uncertainties regarding many aspects of its relationship with the estuary’s physical and biotic resources. Here we use time-series data from 4 trawl surveys and data on environmental attributes collected from throughout the delta smelt’s distribution to identify ranges of conditions acceptable to delta smelt for each of 5 environmental attributes: water-body type, temperature, turbidity, salinity, and prey availability. Low turbidity and elevated water temperatures render a large portion of the estuary seasonally unsuitable for delta smelt. Within areas in which water quality is suitable, patterns of delta smelt occurrences indicate that habitat is found in subregions where channels of intermediate depth adjoin shallow water. In certain subregions, conditions are inadequate for at least one of the environmental attributes for periods up to several months. We suggest a habitat-restoration strategy that can achieve adequate habitat conditions for delta smelt regardless of through-Delta flow levels, and which can be carried out at a number of locations, but not necessarily the same locations, during each life stage.

Initial results from the New Horizons exploration of 2014 MU69, a small Kuiper Belt object

The Kuiper Belt is a distant region of the outer Solar System. On 1 January 2019, the New Horizons spacecraft flew close to (486958) 2014 MU₆₉, a cold classical Kuiper Belt object approximately 30 kilometers in diameter. Such objects have never been substantially heated by the Sun and are therefore well preserved since their formation. We describe initial results from these encounter observations. MU₆₉ is a bilobed contact binary with a flattened shape, discrete geological units, and noticeable albedo heterogeneity. However, there is little surface color or compositional heterogeneity. No evidence for satellites, rings or other dust structures, a gas coma, or solar wind interactions was detected. MU₆₉'s origin appears consistent with pebble cloud collapse followed by a low-velocity merger of its two lobes.

Post-hoc analysis of vitamin D status and reduced risk of preterm birth in two vitamin D pregnancy cohorts compared with South Carolina March of Dimes 2009-2011 rates

BACKGROUND

Two vitamin D pregnancy supplementation trials were recently undertaken in South Carolina: The NICHD (n=346) and Thrasher Research Fund (TRF, n=163) studies. The findings suggest increased dosages of supplemental vitamin D were associated with improved health outcomes of both mother and newborn, including risk of preterm birth (<37 weeks gestation). How that risk was associated with 25(OH)D serum concentration, a better indicator of vitamin D status than dosage, by race/ethnic group and the potential impact in the community was not previously explored. While a recent IOM report suggested a concentration of 20 ng/mL should be targeted, more recent work suggests optimal conversion of 25(OH)D-1,25(OH)2D takes place at 40 ng/mL in pregnant women.

OBJECTIVE

Post-hoc analysis of the relationship between 25(OH)D concentration and preterm birth rates in the NICHD and TRF studies with comparison to Charleston County, South Carolina March of Dimes (CC-MOD) published rates of preterm birth to assess potential risk reduction in the community.

METHODS

Using the combined cohort datasets (n=509), preterm birth rates both for the overall population and for the subpopulations achieving 25(OH)D concentrations of ≤20 ng/mL, >20 to <40 ng/mL, and ≥40 ng/mL were calculated; subpopulations broken down by race/ethnicity were also examined. Log-binomial regression was used to test if an association between 25(OH)D serum concentration and preterm birth was present when adjusted for covariates; locally weighted regression (LOESS) was used to explore the relationship between 25(OH)D concentration and gestational age (weeks) at delivery in more detail. These rates were compared with 2009-2011 CC-MOD data to assess potential risk reductions in preterm birth.

RESULTS

Women with serum 25(OH)D concentrations ≥40 ng/mL (n=233) had a 57% lower risk of preterm birth compared to those with concentrations ≤20 ng/mL [n=82; RR=0.43, 95% confidence interval (CI)=0.22,0.83]; this lower risk was essentially unchanged after adjusting for covariates (RR=0.41, 95% CI=0.20,0.86). The fitted LOESS curve shows gestation week at birth initially rising steadily with increasing 25(OH)D and then plateauing at ∼40 ng/mL. Broken down by race/ethnicity, there was a 79% lower risk of preterm birth among Hispanic women with 25(OH)D concentrations ≥40 ng/mL (n=92) compared to those with 25(OH)D concentrations ≤20 ng/mL (n=29; RR=0.21, 95% CI=0.06,0.69) and a 45% lower risk among Black women (n=52 and n=50; RR=0.55, 95% CI=0.17,1.76). There were too few white women with low 25(OH)D concentrations for assessment (n=3). Differences by race/ethnicity were not statistically significant with 25(OH)D included as a covariate. Compared to the CC-MOD reference group, women with serum concentrations ≥40 ng/mL in the combined cohort had a 46% lower rate of preterm birth overall (n=233, p=0.004) with a 66% lower rate among Hispanic women (n=92, p=0.01) and a 58% lower rate among black women (n=52, p=0.04).

CONCLUSIONS

In this post-hoc analysis, achieving a 25(OH)D serum concentration ≥40 ng/mL significantly decreased the risk of preterm birth compared to ≤20 ng/mL. These findings suggest the importance of raising 25(OH)D levels substantially above 20 ng/mL; reaching 40 ng/mL during pregnancy would reduce the risk of preterm birth and achieve the maximal production of the active hormone.

Post-hoc comparison of vitamin D status at three timepoints during pregnancy demonstrates lower risk of preterm birth with higher vitamin D closer to delivery

There have been observational reports that maternal vitamin D status at baseline and not closest to delivery is a better predictor of pregnancy outcomes, suggesting that a cascade of events is set into motion that is not modifiable by vitamin D supplementation during later pregnancy. To address this issue, in this exploratory post-hoc analysis using correlation and logistic regression, we sought to measure the strength of the association between serum 25(OH)D concentrations at 3 timepoints during pregnancy: baseline, 1st trimester (<16 weeks); 2nd trimester (16-26 weeks); and 3rd trimester (≥27 weeks) and preterm birth. It was hypothesized that the 25(OH)D value closest to delivery would be most significantly associated with preterm birth. To accomplish this objective, the datasets from NICHD (n=333) and Thrasher Research Fund (n=154) vitamin D supplementation pregnancy studies were combined. The results of this analysis were that 25(OH)D values closer to delivery were more strongly correlated with gestational age at delivery than earlier values: 1st trimester: r=0.11 (p=0.02); 2nd trimester: r=0.08 (p=0.09); and 3rd trimester: r=0.15 (p=0.001). When logistic regression was performed with preterm birth (<37 weeks) as the outcome and 25(OH)D quartiles as the predictor variable, adjusting for study and participant race/ethnicity, as with the correlation analysis, the measurements closer to delivery were more significantly associated and had a higher magnitude of effect. That is, at baseline, those who had serum concentrations <50nmol/L (20ng/mL) had 3.3 times of odds of a preterm birth compared to those with serum concentrations ≥100nmol/L (40ng/mL; p=0.27). At 2nd trimester, the odds were 2.0 fold (p=0.21) and at the end of pregnancy, the odds were 3.8 fold (p=0.01). The major findings from this exploratory analysis were: (1) maternal vitamin D status closest to delivery date was more significantly associated with preterm birth, suggesting that later intervention as a rescue treatment may positively impact the risk of preterm delivery, and (2) a serum concentration of 100nmol/L (40ng/mL) in the 3rd trimester was associated with a 47% reduction in preterm births. This article is part of a Special Issue entitled '17th Vitamin D Workshop'.

Short communication: presynchronization for timed artificial insemination in grazing dairy cows by using progesterone for 14 days with or without prostaglandin F2α at the time of progesterone withdrawal

Progesterone-containing devices can be inserted intravaginally for 14 d to presynchronize the estrous cycle for timed artificial insemination (TAI) in beef heifers ("14-day CIDR-PG" or "Show-Me-Synch" program). The progesterone treatment is effective for presynchronization because cattle develop a persistent dominant follicle during treatment that ovulates within 3 d after progesterone removal. The subsequent estrous cycle can be effectively used for a TAI program. Some cattle will retain a functional corpus luteum (CL) for the entire 14-d treatment period and will not be synchronized effectively because the interval to ovulation depends on the lifespan of their existing CL. The objective was to test the effect of a luteolytic dose of PGF(2α) at progesterone removal for improving synchrony of estrus after treatment and increasing conception rate to a subsequent TAI in dairy cows. Postpartum cows (n = 1,021) from 2 grazing dairy herds were assigned to 1 of 2 presynchronization programs that used a controlled internal drug releasing (CIDR) device containing progesterone: 14dCIDR (CIDR in, 14 d, CIDR out; n = 523) or 14dCIDR+PGF(2α) (CIDR in, 14 d, CIDR out, and PGF(2α); n = 498). Cows were body condition scored (BCS; 1 to 5, thin to fat) and tail painted at CIDR removal. Paint score (PS) was recorded after CIDR removal [PS = 0 (all paint removed, indication of estrus), PS = 3 (paint partially removed), or PS = 5 (no paint removed; indication of no estrus)]. At 19 d after CIDR removal, all cows were treated with PGF(2α), 56 h later treated with GnRH, and then 16 h later were TAI. Treating cows with PGF(2α) at CIDR removal increased the percentage with PS = 0 within 5 d (58.1% vs. 68.9%; 14dCIDR vs. 14dCIDR+PGF(2α)). We found no effect of treatment, however, on conception rate at TAI (41.1% vs. 43.6%; respectively). The TAI conception rate increased with increasing BCS and was greater for cows that had PS = 0 within 5 d after CIDR removal. In summary, treating cows with PGF(2α) at CIDR removal increased the percentage of cows with all tail paint removed but did not increase percentage of pregnant cows after TAI.

Principles of epidemiological modelling

Epidemiological modelling can be a powerful tool to assist animal health policy development and disease prevention and control. Models can vary from simple deterministic mathematical models through to complex spatially-explicit stochastic simulations and decision support systems. The approach used will vary depending on the purpose of the study, how well the epidemiology of a disease is understood, the amount and quality of data available, and the background and experience of the modellers. Epidemiological models can be classified into various categories depending on their treatment of variability, chance and uncertainty (deterministic or stochastic), time (continuous or discrete intervals), space (non-spatial or spatial) and the structure of the population (homogenous or heterogeneous mixing). The increasing sophistication of computers, together with greater recognition of the importance of spatial elements in the spread and control of disease, mean that models which incorporate spatial components are becoming more important in epidemiological studies. Multidisciplinary approaches using a range of new technologies make it possible to build more sophisticated models of animal disease. New generation epidemiological models enable disease to be studied in the context of physical, economic, technological, health, media and political infrastructures. To be useful in policy development, models must be fit for purpose and appropriately verified and validated. This involves ensuring that the model is an adequate representation of the system under study and that its outputs are sufficiently accurate and precise for the intended purpose. Finally, models are just one tool for providing technical advice, and should not be considered in isolation from data from experimental and field studies.

Modeling 5-FU AUC-dose relationship to develop a PK dosing algorithm

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Background: 5-fluorouracil (5-FU) is an ideal candidate for pharmacokinetic (PK) dosing. 5-FU is administered based on standard BSA dosing. BSA administration results in highly variable PK and exposure, and potential underdosing in about 50% of patients. Patients with higher 5-FU AUC levels derive greater clinical benefit but with increased risk of toxicity. An immunoassay (OnDose) that measures 5-FU concentration in plasma and reports a computed AUC in mg·h/L has been developed to aid optimization of therapy using PK dosing. The results of an analysis to model the 5-FU AUC-dose change relationship from our clinical database are presented.

Methods: A set of 585 sequential patients from our database receiving FOLFOX6 regimen with 5-FU continuous infusion (CI) over 41-48 hours, with or without bevacizumab, for the adjuvant and metastatic treatment of CRC was used for the preliminary analyses. A subset restricted to include only patients that had at least two consecutive cycles tested, received 1,600-3,600 mg/m2 at the initial test cycle, and had blood sample collection times ≥ 18 hours was used to conduct regression modeling of change in AUC versus change in dose. Outliers such as AUC values < 5 mg·h/L and > 50 mg·h/L were excluded from the analysis.

Results: Our analysis corroborates previous findings that large variability in 5-FU PK measurements exists during the early part of the infusion cycle. The following simple regression model with an R2=0.51 developed over N=307 cycle-pair observations characterizes the AUC-dose relationship as: change in AUC (mg·h/L) = 0.02063 * dose change (mg/m2).

Conclusions: The above model suggests that dose changes ranging from 145 to 720 mg/m2 would be sufficient to adjust the AUC to a potential therapeutic threshold of >20 mg·h/L for most patients. Assuming a 2,400 mg/m2 baseline dose, a maximum 720 mg/m2 dose increase would correspond to a 30% increase, but would likely be needed only by 10% of the patient population with low AUC readings. Our data from the US clinical setting indicate that it is possible to optimize 5-FU therapy by adjusting the dose based on AUC measurement.

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Cardiac arrest following hydrogen peroxide irrigation of a breast wound

Hydrogen peroxide is commonly used for the decontamination of wounds. We report a case of a probable venous oxygen embolism resulting in cardiovascular collapse following irrigation of a necrotic breast wound with hydrogen peroxide. We discuss the differential diagnosis, mechanism of oxygen embolism and question the relative advantages versus disadvantages of using hydrogen peroxide for wound decontamination.

Restructuring of the Australian chicken industry: identification of risk factors for the closure of farms

We conducted a cross-sectional survey of 760 Australian layer chicken farms to identify risk factors associated with the closure of poultry farms. Address data and operating status were obtained for 734 farms and more detailed responses on farm size, structure and management practices from 317 farms (41.7%). The overall prevalence of closed farms was 36.4%. Increased risk of closure was associated with independent ownership [odds ratio (OR) = 2.22, P < 0.01], location within 50 km of the centre of a state capital city (OR = 1.66, P < 0.01), being a layer farm that reared its own pullets (OR = 2.18, P < 0.01) and location within Queensland or South Australia (OR = 3.10, 3.56; both P < 0.01). Analysis of the subset of farms for which more detailed information was available identified location in South Australia (OR = 9.23, P < 0.01), use of cages (OR = 4.36, P < 0.01) and sheds with only natural ventilation (OR = 11.00, P < 0.02) as risk factors associated with a greater risk of farm closure. Our survey found that closed farms were typically independently owned, cage-layer farms located in peri-urban regions near major cities and utilising sheds without assisted ventilation.

A murine model for bone loss from therapeutic and space-relevant sources of radiation

Cancer patients receiving radiation therapy are exposed to photon (gamma/X-ray), electron, and less commonly proton radiation. Similarly, astronauts on exploratory missions will be exposed to extended periods of lower-dose radiation from multiple sources and of multiple types, including heavy ions. Therapeutic doses of radiation have been shown to have deleterious consequences on bone health, occasionally causing osteoradionecrosis and spontaneous fractures. However, no animal model exists to study the cause of radiation-induced osteoporosis. Additionally, the effect of lower doses of ionizing radiation, including heavy ions, on general bone quality has not been investigated. This study presents data developing a murine model for radiation-induced bone loss. Female C57BL/6 mice were exposed to gamma, proton, carbon, or iron radiation at 2-Gray doses, representing both a clinical treatment fraction and spaceflight exposure for an exploratory mission. Mice were euthanized 110 days after irradiation. The proximal tibiae and femur diaphyses were analyzed using microcomputed tomography. Results demonstrate profound changes in trabecular architecture. Significant losses in trabecular bone volume fraction were observed for all radiation species: gamma, (-29%), proton (-35%), carbon (-39%), and iron (-34%). Trabecular connectivity density, thickness, spacing, and number were also affected. These data have clear implications for clinical radiotherapy in that bone loss in an animal model has been demonstrated at low doses. Additionally, these data suggest that space radiation has the potential to exacerbate the bone loss caused by microgravity, although lower doses and dose rates need to be studied.

Efficacy of IV tissue plasminogen activator in acute stroke: does stroke subtype really matter?

BACKGROUND

The National Institute of Neurological Disorders and Stroke (NINDS) trial reported that stroke subtype (e.g., large-artery atherothrombosis, cardioembolism, and lacunae) does not affect response to IV thrombolytic treatment. However, these conclusions were based upon stroke subtypes determined prior to extensive diagnostic evaluation. Because such initial diagnoses are frequently inaccurate, the efficacy of IV recombinant tissue plasminogen activator (rt-PA) based upon verified specific stroke subtypes remains uncertain.

METHODS

The records of consecutive acute stroke patients treated with IV rt-PA at two regional stroke centers were retrospectively reviewed. The final stroke subtype after complete diagnostic evaluation was determined. The relationship between final stroke subtype and response to thrombolytic therapy was then investigated and compared with the results reported in the NINDS trial.

RESULTS

Ninety consecutive patients were studied. After adjusting for baseline NIH Stroke Scale scores, no significant difference in final outcome based on confirmed stroke mechanism was identified.

CONCLUSIONS

These data are consistent with those of the NINDS trial that reported that the efficacy of IV thrombolysis within the 3-hour time window is similar between different stroke subtypes. Based upon these data, allocating treatment of stroke patients with IV rt-PA based upon presumed stroke mechanism may be unnecessary. Such testing may result in time delays that could compromise the efficacy of treatment.

Oxytocin-induced secretion of prostaglandin F2alpha in postpartum beef cows: effects of progesterone and estradiol-17beta treatment

The purpose of the present study was to determine the effect of progesterone or progesterone + estradiol-17beta on oxytocin-induced prostaglandin F2alpha (PGF2alpha) secretion in postpartum beef cows. Thirty-four anestrous postpartum beef cows were ovariectomized (d 32 [Groups 1 to 3] or d 23 [Groups 4 to 6] postpartum [d 0 = parturition]) and allotted to six treatments (Group 1; negative control) to simulate short (Groups 2 through 5) or normal (Group 6) length estrous cycles. Steroid treatments for the respective groups were as follows: Group 1) no estradiol-17beta or progesterone treatment (n = 8; negative control); Group 2) progesterone (d 34 to 40; n = 6); Group 3) estradiol-17beta (d 32 to 33) and progesterone (d 34 to 40; n = 6); Group 4) progesterone (d 23 to 29), no estradiol-17beta (d 32 to 33), and progesterone (d 34 to 40; n = 5); Group 5) progesterone (d 23 to 29), estradiol-17beta (d 32 to 33), and progesterone (d 34 to 40; n = 5); and Group 6) progesterone (d 23 to 29), estradiol-17beta (d 32 to 33), and progesterone (d 34 to 50; n = 4; positive control). Oxytocin (100 IU) was injected (i.v.) at the end of each treatment to test the ability of the postpartum uterus to secrete PGF2alpha as measured by a stable metabolite of PGF2alpha, 15keto-13,14 dihydro-PGF2alpha (PGFM). Peak concentrations ofPGFM (P < 0.08) and total PGFM secreted (area under the curve; P < 0.05) were increased on d 6 following first (Group 2) or second (Group 4) exposure to progesterone and were similar to peak concentrations and total PGFM secreted 16 d following a simulated normal estrous cycle (Group 6). Administration of estradiol-17beta before first progesterone exposure (Group 3) did not reduce peak concentrations of PGFM or total PGFM secreted relative to the preceding groups. Peak concentrations of PGFM (P < 0.08) and total PGFM secreted (P < 0.05) were reduced following a second progesterone exposure, provided that cows were pretreated with estradiol-17beta (Group 5). In summary, oxytocin-induced release of PGFM was inhibited on d 6 following second exposure to progesterone only when cows were pretreated with estradiol-17beta. Therefore, estradiol-17beta and progesterone were both associated with the timing of PGF2, secretion in postpartum cows.

A prospective, randomized, double-blind trial of the use of fibrin sealant for face lifts

Fibrin sealant imitates the final phase of the blood coagulation process. Fibrinogen is converted into fibrin on a tissue surface by the action of thrombin, which is then cross-linked by factor XIIIa, creating a mechanically stable fibrin network. This fibrin network is thought to reduce the amount of postoperative bleeding by sealing capillary vessels and allowing raw operative surfaces to adhere. The authors conducted a prospective, double-blind, randomized, controlled trial on the use of fibrin sealant in 20 consecutive patients undergoing bilateral face lifts by the same surgeon. Each patient was randomized for the use of fibrin sealant on either the right or the left side with the contralateral side acting as the control. Total drainage was recorded on each side for 24 hours before drains were removed. The age range of the patients in the trial (all of whom were women) was 44 to 70 years (mean, 55). The side treated with fibrin glue had a median drainage of 10 ml and the control side 30 ml. The Wilcoxon signed rank test shows a significant difference in drainage between sides (p = 0.002). The reduction in postoperative drainage could also reduce pain and bruising, increasing patient satisfaction with this procedure. The need for drains may also be obviated.

Long-term results of surgical excision and skin grafting for a giant hairy naevus of the face: time for a return to conventional wisdom?

In a publication climate demanding modern innovative treatments for congenital giant hairy naevi, we report a case with excellent long-term results following early surgical excision and split-thickness skin grafting.

Statistical analysis of the long-term effects of recombinant human deoxyribonuclease on pulmonary function in cystic fibrosis patients

The problem of evaluating the long-term effects of recombinant human deoxyribonuclease (rhDNase) on forced expiratory volume in one second (FEV1) in cystic fibrosis (CF) patients was considered. A two-stage mixed effects model, incorporating relevant predictive variables, captured the diverse patterns of decline of FEV1 for patients with different demographic characteristics. Based on the results of modeling the dropout process, it is clear that the probability of early dropout was closely related to patient's responsiveness to rhDNase treatment. Failure to consider the existence of informative censoring severely biased the estimates of the rate of decline and affected the interpretation of the results.

Intravenous tissue-type plasminogen activator for treatment of acute stroke: the Standard Treatment with Alteplase to Reverse Stroke (STARS) study

CONTEXT

Tissue-type plasminogen activator (tPA) is the only therapy for acute ischemic stroke approved by the Food and Drug Administration.

OBJECTIVE

To assess the safety profile and to document clinical outcomes and adverse events in patients treated with intravenous tPA for acute stroke in clinical practice.

DESIGN AND SETTING

Prospective, multicenter study of consecutive patients enrolled between February 1997 and December 1998 at 57 medical centers in the United States (24 academic and 33 community).

INTERVENTION

Intravenous tPA (recombinant alteplase).

PATIENTS

Three hundred eighty-nine patients with a mean age of 69 years (range, 28-100 years); 55% were men.

MAIN OUTCOME MEASURES

Time intervals between stroke symptom onset, hospital arrival, and treatment with tPA; pretreatment computed tomographic scan results, intracerebral hemorrhage, and major systemic bleeding. The modified Rankin Scale score was used to assess clinical outcomes at 30 days.

RESULTS

Median time from stroke onset to treatment was 2 hours 44 minutes, and the median baseline National Institutes of Health Stroke Scale score was 13. The 30-day mortality rate was 13%. At 30 days after treatment, 35% of patients had very favorable outcomes (modified Rankin score, 0-1) and 43% were functionally independent (modified Rankin score, 0-2). Thirteen patients (3.3%) experienced symptomatic intracerebral hemorrhage, including 7 who died. Twenty-eight patients (8.2%) had asymptomatic intracerebral hemorrhage within 3 days of treatment with tPA. Protocol violations were reported for 127 patients (32.6%), and included treatment with tPA more than 3 hours after symptom onset in 13.4%, treatment with anticoagulants within 24 hours of tPA administration in 9.3%, and tPA administration despite systolic blood pressure exceeding 185 mm Hg in 6.7%. A multivariate analysis found predictors of favorable outcome to be a less severe baseline National Institutes of Health Stroke Scale score, absence of specific abnormalities (effacement or hypodensity of >33% of the middle cerebral artery territory or a hyperdense middle cerebral artery) on the baseline computed tomographic scan, an age of 85 years or younger, and a lower mean arterial pressure at baseline.

CONCLUSIONS

This study, conducted at multiple institutions throughout the United States, suggests that favorable clinical outcomes and low rates of symptomatic intracerebral hemorrhage can be achieved using tPA for stroke treatment.

Dynamically allocating treatment when the cost of goods is high and drug supply is limited

Large-scale production of proteins by cell culture and subsequent purification for use in novel medical therapies is a slow and complex process. During the early phases of development of manufacturing processes, contamination and replication errors cause entire batches of material to be wasted. As a result, the cost of goods for large-molecule therapies in early clinical development can be significant, and the supply limited. When designing clinical trials to test expensive biological compounds with limited supply, sponsoring companies want to minimize the waste of drug, that is, to maintain small inventories of drug at the investigational hospitals. We must, however, weigh the benefits of smaller inventories against the costs of increased numbers of shipments to resupply when rapid enrollment causes shortages of drug. A well-planned randomization scheme may be able to balance these objectives. This paper demonstrates how a dynamic randomization algorithm can be used to maintain smaller drug inventory at hospitals than a typical permuted block randomization list plan, and how well it automatically restores balance when the shortage of drug causes assignment of alternate treatments.

Drug-induced thrombocytopenia: a systematic review of published case reports

PURPOSE

To determine the strength of clinical evidence for individual drugs as a cause of thrombocytopenia.

DATA SOURCES

All English-language reports on drug-induced thrombocytopenia.

STUDY SELECTION

Articles describing thrombocytopenia caused by heparin were excluded from review. Of the 581 articles reviewed, 20 were excluded because they contained no patient case reports. The remaining 561 articles reported on 774 patients.

DATA EXTRACTION

Two of the authors used a priori criteria to independently review each patient case report. Two hundred fifty-nine patient case reports were excluded from further review because of lack of evaluable data, platelet count of 100000 cells/microL or more, use of cytotoxic or nontherapeutic agents, occurrence of drug-induced systemic disease, or occurrence of disease in children. For the remaining 515 patient case reports, a level of evidence for the drug as the cause of thrombocytopenia was assigned. Data on bleeding complications and clinical course were recorded.

DATA SYNTHESIS

The evidence supported a definite or probable causal role for the drug in 247 patient case reports (48%). Among the 98 drugs described in these reports, quinidine was mentioned in 38 case reports, gold in 11, and trimethoprim-sulfamethoxazole in 10. Of the 247 patients described in the case reports, 23 (9%) had major bleeding and 2 (0.8%) died of bleeding.

CONCLUSIONS

Many reports of drug-induced thrombocytopenia do not provide evidence supporting a definite or probable causal relation between the disease and the drug. Future patient case reports should incorporate standard criteria to clearly establish the etiologic role of the drug.

Detection system for reaction-rate analysis in a low-volume proteinase-inhibition assay

High-throughput screening of large combinatorial chemical libraries in biochemical assays will benefit from reduced reagent volume and increased speed of measurement. Standard assays typically are performed in 96-well microtiter plates having 200-microL well volumes and up to an hour of incubation time. In this paper, we demonstrate a technique for precise and rapid measurement of the progress of an enzymatic reaction and its inhibition with reduced volume and time (for this work, the assay was mixed at the 200-microL level and detected in 2-microL volumes with minutes of total assay time). Directly measuring the enzyme activity in the small volume format yields a precise value for the median inhibitory concentration (IC50) of an inhibitor compound. The model assay is the endoproteolytic cleavage of a small fluorogenic peptide by human neutrophil collagenase (MMP-8). The fluorogenic peptide was labeled at one end with a UV/blue fluorophore (N-methylanthranilyl) and at the other end with a quencher (dinitrophenol). To generate inhibition data, a hydroxamate peptide analog inhibitor of collagenase, actinonin, was included in the reaction. The experiments were performed using ultraviolet laser illumination (325 nm wavelength) and parallel fluorescence detection by a cooled, charge-coupled-device camera system to increase sensitivity and speed. The assay volume was reduced to 2 microL for data collection, and the total time for mixing, incubation, and measurement was less than 6 min. For comparison to a standard format, the same assay was performed in a 96-well microtiter plate in 200 microL using 30 min of incubation and measurement in a microtiter plate fluorimeter. Median inhibitory concentrations (IC50) for actinonin of 73 +/- 16 and 100 +/- 14 nM were obtained in the 2- and 200-microL assays, respectively. One concern with assay miniaturization and increases in throughput is a potential loss of precision and accuracy. Laser excitation and parallel detection of fluorescence is a promising approach for increased speed and reduced cost without loss of precision for proteinase inhibition assays.

Randomized trial of an oral platelet glycoprotein IIb/IIIa antagonist, sibrafiban, in patients after an acute coronary syndrome: results of the TIMI 12 trial. Thrombolysis in Myocardial Infarction

BACKGROUND

Inhibitors of the platelet glycoprotein IIb/IIIa receptor given intravenously have been shown to be effective in reducing ischemic complications after coronary angioplasty and in unstable angina, making this a promising new class of agents for the treatment and prevention of ischemic events in patients with acute coronary syndromes. Sibrafiban (Ro 48-3657) is an oral, peptidomimetic, selective antagonist of the glycoprotein IIb/IIIa receptor.

METHODS AND RESULTS

The Thrombolysis in Myocardial Infarction (TIMI) 12 trial was a phase II, double-blind, dose-ranging trial designed to evaluate the pharmacokinetics (PK), pharmacodynamics (PD), safety, and tolerability of sibrafiban in 329 patients after acute coronary syndromes. In the PK/PD cohort of TIMI 12, 106 patients were randomized to receive one of seven dosing regimens of sibrafiban, ranging from 5 mg daily to 10 mg twice daily for 28 days. In the safety cohort, 223 patients were randomized to one of four dose regimens of sibrafiban (ranging from 5 mg twice daily to 15 mg once daily) or aspirin for 28 days. High levels of platelet inhibition were achieved: mean peak values ranged from 47% to 97% inhibition of 20 micromol/L ADP-induced platelet aggregation on day 28 across the seven doses. Twice-daily dosing provided more sustained platelet inhibition (mean inhibition, 36% to 86% on day 28), whereas platelet inhibition returned to baseline levels by 24 hours with once-daily dosing. Major hemorrhage occurred in 1.5% of patients treated with sibrafiban and in 1.9% of patients treated with aspirin. Protocol-defined "minor" bleeding, usually mucocutaneous, occurred in 0% to 32% of patients in the various sibrafiban groups and in none of the patients treated with aspirin. Minor bleeding was related to total daily dose (P=.002), once- versus twice-daily dosing (P<.0001), renal function (P<.0001), and presentation with unstable angina (P<.01).

CONCLUSIONS

The oral glycoprotein IIb/IIIa antagonist sibrafiban achieved effective, long-term platelet inhibition with a clear dose-response but at the expense of a relatively high incidence of minor bleeding. Oral IIb/IIIa inhibition deserves further study as a new treatment strategy in patients after acute coronary syndromes.

rhDNase as an example of recurrent event analysis

We consider counting process methods for analysing time-to-event data with multiple or recurrent outcomes, using the models developed by Anderson and Gill, Wei, Lin and Weissfeld and Prentice, Williams and Peterson. We compare the methods, and show how to implement them using popular statistical software programs. By analysing three data sets, we illustrate the strengths and pitfalls of each method. The first example is simulated and involves the effect of a hidden covariate. The second is based on a trial of gamma interferon, and behaves remarkably like the first. The third and most interesting example involves both multiple events and discontinuous intervals at risk, and the three approaches give dissimilar answers. We recommend the AG and marginal models for the analysis of this type of data.

Effect of six-hour exposure to nitrogen dioxide on early-phase nasal response to allergen challenge in patients with a history of seasonal allergic rhinitis

BACKGROUND

Recent studies have suggested that exposure to air pollutants may enhance the airway responsiveness of susceptible individuals to inhaled allergen.

METHODS

To investigate the effect of exposure to nitrogen dioxide (NO2) on nasal airways resistance (NAR) and inflammatory mediators in nasal lavage fluid, eight subjects with a history of seasonal allergic rhinitis, who were tested out of season, were exposed in a randomized single-blind, crossover study to either air or 400 ppb NO2 for 6 hours. The changes in NAR and eosinophil cationic protein (ECP), mast cell tryptase (MCT), neutrophil myeloperoxidase (MPO), and interleukin-8 (IL-8) in nasal lavage fluid before and after exposure were evaluated. Another group of eight subjects with a history of seasonal allergic rhinitis were also randomized to exposure to air or 400 ppb NO2 for 6 hours and then challenged with allergen, before evaluation for changes in NAR and changes in ECP, MCT, MPO, and IL-8 in nasal lavage fluid.

RESULTS

Exposure to air or NO2 did not alter either NAR or the levels of ECP, MCT, MPO, or IL-8 in nasal lavage fluid. Allergen challenge after exposure to both air and NO2 significantly (p < 0.05) increased levels of MCT, but not MPO and IL-8 in the nasal lavage fluid. In addition, allergen challenge after exposure to NO2 but not air, significantly increased levels of only ECP in nasal lavage fluid (p < 0.05).

CONCLUSIONS

These results suggest that acute exposure to NO2 at concentrations found at the curbside in heavy traffic during episodes of pollution, may "prime" eosinophils for subsequent activation by allergen in individuals with a history of seasonal allergic rhinitis.

Expression of follicle-stimulating hormone and luteinizing hormone receptor messenger ribonucleic acids in bovine follicles during the first follicular wave

The objective of the present study was to characterize expression of mRNAs encoding FSH and LH receptors during follicular development and at different stages of the first follicular wave in cattle. Following estrus, groups of heifers (3-5 per group) were ovariectomized on the day of initiation of the first follicular wave (as determined by ultrasonography; Day 0), or on Days 2, 4, 6, 8, or 10 after initiation of the first wave. FSH and LH receptor mRNAs were detected within follicles > or = 4 mm and in some smaller follicles by in situ hybridization and were quantified by image analysis. FSH receptor mRNA was expressed in granulosa cells of all growing follicles, starting in some follicles with only one layer of granulosa cells. Irrespective of day of the follicular wave, the level of expression of FSH receptor mRNA in granulosa cells of healthy antral follicles ranging from 0.5 to 14 mm in diameter did not vary significantly with follicular size (r = 0.02, p > 0.10). Expression of LH receptor mRNA was first observed in theca interna cells of follicles shortly after antral formation. Irrespective of day of the follicular wave, the levels of LH receptor mRNA in theca interna cells of healthy antral follicles ranging from 0.5 to 14 mm increased with follicular size (r = 0.39, p < 0.01). In granulosa cells, LH receptor mRNA was expressed only in healthy follicles > 9 mm in diameter and was first observed in the dominant follicles collected on Day 4. Expression of mRNA for LH receptor, but not for FSH receptor, changed (p < 0.01) with the stage of the first follicular wave.(ABSTRACT TRUNCATED AT 250 WORDS)

Characterization of ovarian follicular cysts and associated endocrine profiles in dairy cows

It is generally accepted that ovarian follicular cysts (cysts) are nonovulatory follicular structures that contribute to extended calving intervals. Follicle/cyst dynamics and the etiology of cysts are unclear. The present study was conducted to characterize follicle/cyst dynamics and to define endocrine changes (etiology) associated with cyst development. Thirty-two dairy cows were studied: controls (n = 6), cows with spontaneously occurring cysts (n = 14), and cows in which cysts were induced by exogenous steroid treatment (n = 12). Ovaries of cows were scanned daily by ultrasonography to record follicle/cyst dynamics. Blood was collected to determine endocrine changes associated with follicle/cyst life span. Three ovarian responses in cows with cysts were observed: persistence of cysts, turnover of cysts, or spontaneous recovery (self-recovered; turnover of cysts and replacement with a follicle that ovulated). Mean maximum size of cysts was larger (p < 0.05) than that of ovulatory follicles (2.80 +/- 0.19 vs. 1.60 +/- 0.05 cm). Mean interval from initial detection of follicle/cyst wave to detection of a new follicle/cyst wave in cows with cysts was longer (13.0 +/- 1.1 days; p < 0.05) and more variable (6 to 26 days; p < 0.05) than in controls (8.5 +/- 0.5 days and 6-14 days, respectively). Cysts grew at the same rate as follicles but continued to grow for an additional period of time. A transient increase in FSH preceded detection of all follicle/cyst waves.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of messenger ribonucleic acid encoding cytochrome P450 side-chain cleavage, cytochrome p450 17 alpha-hydroxylase, and cytochrome P450 aromatase in bovine follicles during the first follicular wave

The objective of the present study was to investigate changes in the expression of messenger RNAs (mRNAs) encoding cytochrome P450 side-chain cleavage (P450scc), cytochrome P450 17 alpha-hydroxylase (P450c17), and cytochrome P450 aromatase (P450arom) at different stages of the first follicular wave of the bovine estrous cycle. Groups of heifers (three to five per group) were ovariectomized on the day of initiation of the first follicular wave (as determined by ultrasonography, day 0) or on days 2, 4, 6, 8, and 10 after initiation of the first follicular wave following estrus. Expression of mRNAs encoding P450scc, P450c17, and P450arom was detected by in situ hybridization and quantified by image analysis. P450scc mRNA was localized to theca interna cells of large preantral follicles and also to granulosa cells of follicles 4 mm or greater in diameter. mRNA for P450c17 was localized exclusively to theca interna cells, whereas P450arom mRNA was localized to granulosa cells of follicles 4 mm or greater in diameter. There were changes in mRNA levels for all three enzymes in thecal and/or granulosa cells at different times of the first follicular wave. Before identification of the dominant follicle (i.e. on days 0 and 2), there was no change in expression of P450scc and P450c17 mRNAs, whereas expression of P450arom mRNA was higher on day 2 than on day 0. Maximal mRNA levels for all three enzymes were observed on day 4. By day 6, P450scc and P450c17 mRNA levels were reduced compared to those on day 4, whereas P450arom mRNA levels remained elevated. On day 8, mRNA levels for all three enzymes were reduced. After initiation of the second follicular wave (day 10), dominant follicles from the first wave were at an advanced stage of atresia. P450scc and P450arom mRNAs were undetectable in granulosa cells, and very low levels of P450scc and P450c17 mRNAs were observed in theca interna cells. Before identification of the dominant follicle, mRNA levels for all three enzymes were similar within a cohort of follicles. Therefore, expression of these enzymes may not be associated with the mechanism of selection of the dominant follicle during a follicular wave.

Comparison of a new antihistaminic and antiallergic compound KW 4679 with terfenadine and placebo on skin and nasal provocation in atopic individuals

The effects of three oral doses of a new compound KW 4679 thought to have both antihistaminic and antiallergic properties were compared with terfenadine and placebo in a double-blind cross-over trial in 15 volunteers with seasonal allergic rhinitis. Comparison of the effect of the treatments with either 2.5, 5 or 10 mg b.i.d. of KW 4679, 60 mg b.i.d. of terfenadine or placebo was made on the response to histamine and grass pollen skin-prick testing. Nasal provocation testing with grass pollen was performed on the eighth day of treatment. Nasal airway resistance (NAR) was measured using active posterior rhinomanometry and the dose of grass pollen which caused a 200% increase in NAR was determined. The number of sneezes in the first 12 min was counted. Compared with placebo all doses of KW 4679 and terfenadine significantly inhibited the skin weal response to histamine and grass pollen (P < 0.001). The inhibitory effect of KW 4679 on both histamine and allergen induced skin weals was significantly greater than that of terfenadine (P = 0.001 and P = 0.049 respectively). The results of nasal challenges with grass pollen showed that all doses of KW 4679 and terfenadine were effective in reducing sneeze counts (P < 0.001), though there were no significant effects on allergen induced increase in NAR. All three doses of KW 4679 were generally well tolerated. Drowsiness was reported by some of the volunteers on KW 4679 and one volunteer reported drowsiness whilst taking placebo. Slight and reversible rises in AST and ALT concentrations were observed; these were not considered clinically significant.

Placebo-controlled immunopathologic study of four months of inhaled corticosteroids in asthma

The effect of prolonged inhaled corticosteroid treatment on bronchial immunopathology was assessed in 25 nonsmoking mildly asthmatic subjects previously receiving intermittent inhaled beta 2-agonist alone. Inhaled beclomethasone dipropionate (BDP), 500 micrograms twice per day or placebo was administered for 4 mo in a double-blind parallel group study. Histamine bronchial provocation, fiberoptic bronchoscopic biopsy, and bronchoalveolar lavage (BAL) were performed before and after treatment. There was no difference in bronchial responsiveness or lung function between groups. In patients treated with BDP compared with placebo, there was a significant reduction in toluidine blue-staining mast cells (p = 0.028) and total (p = 0.005) and activated eosinophils (p = 0.05) in biopsies but no difference in eosinophils or eosinophil cationic protein in BAL. Granulocyte-macrophage colony-stimulating factor expression was significantly reduced in the bronchial epithelium, and the thickness of Type III collagen deposition in the bronchial lamina reticularis reduced from 29.7 +/- 4.4 to 19.8 +/- 3.4 microns (mean +/- 95% confidence interval) (p = 0.04). No change in helper or activated helper T cells occurred. Prolonged BDP treatment reduces inflammatory infiltration, proinflammatory cytokine expression, and subepithelial collagen deposition, a recognized abnormality in asthma.

Luteal function after intrauterine infusion of recombinant bovine interferon-alpha I1 into postpartum beef cows expected to have short or normal luteal phases

This study was conducted to determine whether intrauterine infusion of recombinant bovine interferon-alpha I1 (rboIFN-alpha I1), which has 70% sequence identity to bovine trophoblast protein-1, will prevent regression of corpora lutea anticipated to have a short lifespan. Twenty-six beef cows in good body condition were allotted to four treatment groups at parturition in a 2 x 2 factorial design. Treatments were: group 1, saline; group 2, rboIFN-alpha I1; group 3, norgestomet-saline; and group 4, norgestomet-rboIFN-alpha I1. Norgestomet implants were inserted on days 21-24 postpartum and removed 9 days later (before injection of human chorionic gonadotrophin (hCG)). Ovulation was induced 30 to 33 days postpartum with 5000 or 10,000 iu hCG. Groups 1 (n = 7) and 3 (n = 5) were given intrauterine infusions (rectocervical approach) twice daily with saline on days 1-12 or 13-24 after hCG injection, respectively. Cows allotted to groups 2 (n = 8) and 4 (n = 6) were given intrauterine infusions (rectocervical approach) of 2 mg rboIFN-alpha I1 twice daily on days 1-12 or 13-24 after hCG injection, respectively. Treatment with both norgestomet and rboIFN-alpha I1 delayed (P less than 0.01) luteolysis. Lengths of luteal phases (days; mean +/- SEM) were 8.4 +/- 0.7 (group 1, saline), 14.1 +/- 1.0 (group 2, rboIFN-alpha I1), 18.6 +/- 1.3 (group 3, norgestomet-saline) and 20.8 +/- 1.2 (group 4, norgestomet-rboIFN-alpha I1). Concentration of progesterone in serum was similar among all groups the first 6 days following hCG-induced ovulation, but differed (P less than 0.01) thereafter.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of nordihydroguaiaretic acid on luteal phase length and oxytocin-induced release of prostaglandin F2 alpha in heifers

Two experiments were conducted to determine if intrauterine infusion of nordihydroguaiaretic acid, a lipoxygenase pathway inhibitor, would delay luteolysis (Experiment 1) and inhibit oxytocin-induced release of prostaglandin F2 alpha (as measured by the stable prostaglandin F2 alpha metabolite, 15-keto-13,14-dihydroprostaglandin F2 alpha) in plasma on d 16 (d 0 = estrus) of the estrous cycle (Experiment 2). Nordihydroguaiaretic acid (20 mg) or saline was infused twice daily into the uterus on d 14 to 23 (Experiment 1) or d 14 to 20 (Experiment 2) postestrus, respectively. In Experiment 1 and 2, mean concentration of progesterone was higher and luteolysis was delayed in nordihydroguaiaretic acid-infused heifers compared with saline-infused heifers. In Experiment 2, saline or oxytocin (100 IU, i.v.) was injected into each heifer on d 16 postestrus to stimulate the release of prostaglandin F2 alpha from the uterus. Mean concentration of 15-keto-13,14-dihydroprostaglandin F2 alpha increased within 1.5 h postinjection in heifers infused with saline, whereas concentration of 15-keto-13,14-dihydroprostaglandin F2 alpha in nordihydroguaiaretic acid-infused heifers did not increase within the same time period. Thus, nordihydroguaiaretic acid may inhibit both the lipoxygenase and cyclooxygenase pathways of arachidonic acid metabolism and therefore delay luteolysis.

Lawrence design first metatarsophalangeal prosthesis. A complication

A complication involving tibial sesamoid impingement within the hinge of the Lawrence first metatarsophalangeal implant is described. The authors believe that this particular problem may be accentuated by the Lawrence design, which preserves the sesamoid apparatus.

Depression and bulimia: the link between depression and bulimic cognitions

This study assessed the link between bulimic and depressive cognitions. Twenty-nine bulimics and 16 controls from the general population were first assessed on levels of depression using the Schedule for Affective Disorders and Schizophrenia-Change Version and the Beck Depression Inventory (BDI). Bulimics were significantly more depressed than controls. Bulimics differed significantly from controls on all cognitive measures associated with depression (Automatic Thoughts Questionnaire, Dysfunctional Attitude Scale, and Attributional Style Questionnaire), but differences on these measures were nonsignificant when depression, as measured by the BDI, was controlled. Bulimics differed from controls regardless of level of depression on the three scales of the Restraint Inventory, the Rationalization and All-or-None scales of the Thoughts About Eating Inventory, and most of the eight scales of the Eating Disorders Inventory. Bulimics showed more maladaptive thinking associated with depression, but these differences likely reflect the levels of depression for each group. The differences on the measures of cognitive and behavioral symptoms of bulimia remained when the level of depression was controlled statistically. This suggests that although depression can be frequently diagnosed in a bulimic sample, specific maladaptive cognitions and behaviors reflect a distinct disorder (bulimia) and are not simply the expression of an affective disorder.

Depression and bulimia: The link between depression and bulimic cognitions

This study assessed the link between bulimic and depressive cognitions. Twenty-nine bulimics and 16 controls from the general population were first assessed on levels of depression using the Schedule for Affective Disorders and Schizophrenia-Change Version and the Beck Depression Inventory (BDI). Bulimics were significantly more depressed than controls. Bulimics differed significantly from controls on all cognitive measures associated with depression (Automatic Thoughts Questionnaire, Dysfunctional Attitude Scale, and Attributional Style Questionnaire), but differences on these measures were nonsignificant when depression, as measured by the BDI, was controlled. Bulimics differed from controls regardless of level of depression on the three scales of the Restraint Inventory, the Rationalization and All-or-None scales of the Thoughts About Eating Inventory, and most of the eight scales of the Eating Disorders Inventory. Bulimics showed more maladaptive thinking associated with depression, but these differences likely reflect the levels of depression for each group. The differences on the measures of cognitive and behavioral symptoms of bulimia remained when the level of depression was controlled statistically. This suggests that although depression can be frequently diagnosed in a bulimic sample, specific maladaptive cognitions and behaviors reflect a distinct disorder (bulimia) and are not simply the expression of an affective disorder.