One-year implant survival following lateral window sinus augmentation using plasma rich in growth factors (PRGF): a retrospective study

Background

The aim of this study was to assess one-year implant survival after lateral window sinus augmentation using PRGF combined with various bone grafting materials.

Material and Methods

This was a retrospective chart review and radiographic analysis of patients that had undergone lateral window sinus augmentation with PRGF and had dental implants placed at least 6 months post augmentation. All implants included were followed up for at least one year after placement. Demographic, sinus and implant related characteristics (residual ridge height, sinus membrane perforation, type of graft material, implant length and width and ISQ at placement) were analyzed.

Results

A total of 31 patients with 39 sinus augmentations and 48 implants were included. The mean follow up was 22.8 ± 9.9 months. Implant survival was 95.8%, with 2 implants overall failing. Among all the variables assessed, the only one found to be associated with an increased risk for implant failure was the use of xenograft as bone grafting material in the sinus.

Conclusions

Within the limitations of this study, dental implants placed in maxillary sinuses grafted with PRGF in combination with bone grafting materials, exhibit high implant survival rates after at least one year follow up.

Key words:PRGF, sinus graft, growth factors, implant survival, platelet concentrates.

Development and prospective in-patient proof-of-concept validation of a surface photogrammetry + CT-based volumetric motion model for lung radiotherapy

PURPOSE

We develop and validate a motion model that uses real-time surface photogrammetry acquired concurrently with four-dimensional computed tomography (4DCT) to estimate respiration-induced changes within the entire irradiated volume, over arbitrarily many respiratory cycles.

METHODS

A research, couch-mounted, VisionRT (VRT) system was used to acquire optical surface data (15 Hz, ROI = 15 × 20 cm² ) from the thoraco-abdominal surface of a consented lung SBRT patient, concurrently with their standard-of-care 4DCT. The end-exhalation phase from the 4DCT was regarded as reference and for each remaining phase, deformation vector fields (DVFs) with respect to the reference phase were computed. To reduce dimensionality, the first two principal components (PCs) of the matrix of nine DVFs were calculated. In parallel, ten phase-averaged VRT surfaces were created. Surface DVFs and corresponding PCs were computed. A principal least squares regression was used to relate the PCs of surface DVF to those of volume DVFs, establishing a relationship between time-varying surface and the underlying time-varying volume. Proof-of-concept validation was performed during each treatment fraction by concurrently acquiring 30 s time series of real-time surface data and "ground truth" kV fluoroscopic data (FL). A ray-tracing algorithm was used to create a digitally reconstructed fluorograph (DRF), and motion trajectories of high-contrast, soft-tissue, anatomical features in the DRF were compared with those from kV FL.

RESULTS

For five of the six fluoroscopic acquisition sessions, the model out-performed 4DCT in predicting contour Dice coefficient with respect to fluoroscopy-derived contours. Similarly, the model exhibited a marked improvement over 4DCT for patch positions on the diaphragm. Model patch position errors varied from 5 to -15 mm while 4DCT errors ranged between 5 and -22.4 mm. For one fluoroscopic acquisition, a marked change in the a priori internal-external correlation resulted in model errors comparable to those of 4DCT.

CONCLUSIONS

We described the development and a proof-of-concept validation for a volumetric motion model that uses surface photogrammetry to correlate the time-varying thoraco-abdominal surface to the time-varying internal thoraco-abdominal volume. These early results indicate that the proposed approach can result in a marked improvement over 4DCT. While limited by the duration of the fluoroscopic acquisitions as well as the resolution of the acquired images, the DRF-based proof-of-concept technique developed here is model-agnostic, and therefore, has the potential to be used as an in-patient validation tool for other volumetric motion models.

A systematic review of non-surgical treatments for lentigo maligna

Lentigo maligna (LM) is the most common melanocytic malignancy of the head and neck. If left untreated, LM can progress to lentigo maligna melanoma (LMM). Complete surgical excision is the gold standard for treatment, however, due to the location, size, and advanced age of patients, surgery is not always acceptable. As a result, there is ongoing interest in alternative, less invasive treatment modalities. The objective was to provide a structured review of key literature reporting the use of radiotherapy, imiquimod and laser therapy for the management of LM in patients where surgical resection is prohibited. An independent review was conducted following a comprehensive search of the National Library of Medicine using MEDLINE and PubMed, Embase, Scopus, ScienceDirect and Cochrane Library databases. Data were presented in tabular format, and crude data pooled to calculate mean recurrence rates for each therapy. 29 studies met the inclusion criteria: radiotherapy 10; topical imiquimod 10; laser therapies 9. Radiotherapy demostrated recurrence rates of up to 31% (mean 11.5%), with follow-up durations of 1-96 months. Topical imiquimod recurrence rates were up to 50% (mean 24.5%), with follow-up durations of 2-49 months. Laser therapy yielded recurrence rates of up to 100% (mean 34.4%), and follow-up durations of 8-78 months. in each of the treatment series the I(2) value measuring statistical heterogeneity exceeded the accepted threshold of 50% and as such a meta-analysis of included data were inappropriate. For non-surgical patients with LM, radiotherapy and topical imiquimod were efficacious treatments. Radiotherapy produced superior complete response rates and fewer recurrences than imiquimod although both are promising non-invasive modalities. There was no consistent body of evidence regarding laser therapy although response rates of up to 100% were reported in low quality studies. A prospective comparative trial is indicated and would provide accurate data on the long-term efficacy and overall utility of these treatments.

Kidney paired donation: a payer perspective

Kidney transplantation is the most cost-effective and clinically effective form of renal replacement therapy. Due to long wait times for deceased donors, kidney transplantation is not available to many patients with incompatible living donors. Increased access to kidney transplantation is a shared goal that can be achieved through kidney paired donation (KPD). A single, national system of KPD administered to a set of clinical and ethical standards determined by a consensus of stakeholders including recipients, donors, providers, payers and the United States federal government will provide the best opportunity to offer kidney transplantation to the most people and particularly to those currently unlikely to receive a transplant. We propose that this system will use uniform tissue typing algorithms and a computerized donor and recipient matching program using a national pool of willing donors. The proposed system can be managed best through a single administrative structure that takes advantage of uniform donor evaluation and management with a standardized organ acquisition charge that recognizes that the current lack of standardization contributes to delays in transplantation and payment to programs. This program will use the existing Organ Procurement Organization infrastructure to manage the logistics of organ acquisition, transportation and billing.

Use of Filgrastim (r-metHuG-CSF) in Human Immunodeficiency Virus Infection

In 2008, an estimated 33.4 million individuals worldwide were infected with the human immunodeficiency virus (HIV) [1]. Only a few years ago, infection with HIV almost invariably culminated in the development of the acquired immunodeficiency syndrome (AIDS), characterized by severe depletion of CD4⁺ lymphocytes leading to derangements predominantly affecting cell-mediated immunity, but affecting humoral immunity as well [2]. In the later stages of AIDS, neutropenia and neutrophil functional deficits were common sequelae of HIV infection, other opportunistic infections, or HIV- or opportunistic infection-related treatment [3]. The care of the HIV-infected patient was palliative in nature, and the possibility that use of filgrastim (rHuG-CSF) might extend survival in late-stage AIDS patients with severe neutropenia or severe opportunistic infections, or might be a treatment for HIV infection itself, was explored [4]. Subsequently, however, the development of protease inhibitors and the widespread adoption of their use in multidrug regimens of highly active antiretroviral therapy (HAART) revolutionized the care of HIV-infected patients, and the number of patients dying from HIV decreased dramatically [5].

The Safety Profile of Filgrastim and Pegfilgrastim

The discovery of endogenous proteins that regulate hematopoiesis led to the identification of human granulocyte colony-stimulating factor (G-CSF). With the advent of recombinant DNA technology, it became possible to manufacture bioactive recombinant proteins for medicinal use. Since the approval of recombinant human G-CSF (rHuG-CSF), such as filgrastim in 1991 and pegfilgrastim in 2002, millions of patients at risk for severe myelosuppression have received these products. Overall, filgrastim and pegfilgrastim have a high margin of safety for short-term use; however, rare severe adverse events have emerged and questions remain regarding the long-term safety and consequences of use of these products. This chapter primarily focuses on the safety and adverse event profile of the most widely used commercially available rHuG-CSF, Neupogen (filgrastim) and Neulasta [a modified (pegylated) filgrastim, pegfilgrastim]. As safety information can change rapidly, we suggest readers consult the latest package inserts for any changes that have occurred from the time of this writing. Other chapters in this volume discuss key studies in specific disease settings in greater detail than is the purview of this chapter, and we encourage the interested reader to reference them for further information.

Clinical outcomes of adult patients with primary intracranial germinomas treated with low-dose craniospinal radiotherapy and local boost

The authors document the long term follow up of adult patients with histologically proven primary intracranial germinoma treated with radiotherapy alone using a craniospinal with local boost technique. A retrospective review was conducted on adults diagnosed with intracranial germinoma who received radiotherapy at the Princess Margaret Hospital, Toronto from 1990 to 2007. The study group consisted of 10 males with a median age of 24.1 years. All patients received radiotherapy alone using craniospinal radiotherapy and local boost. There were 10 patients (all male) with a median follow up of 10.9 years (range 2.2-18.9 years). At date of last follow up all patients were still alive, none with relapsed disease. Seven of ten patients (70%) had panhypopituitarianism prior to commencing radiotherapy and hormonal function was not affected in those with an intact pituitary axis. There was no reported cognitive decline in the treated cohort. For adult intracranial germinomas, with long term follow up, low-dose craniospinal radiotherapy with in field boost is highly effective with minimal morbidity.

Clinical trial registries and clinical trial result posting: new paradigm for medical writers

Clinical trial registries and posting of clinical trial results have recently become standard procedures for drug development. Several groups, including journal editors and professional trade organizations have called for legislation or have mandated terms or both for the public disclosure of current trials and the results of the clinical trials within a short timeframe after the trial has ended.

Vacuum and forceps training in residency: experience and self-reported competency

OBJECTIVE

Determine chief residents' experience with vacuum and forceps deliveries and self-perceived competencies with the procedures.

STUDY DESIGN

Study 1: A written questionnaire was mailed to all fourth year residents in US RRC approved Ob/Gyn programs. Study 2: The study was replicated using a web-based survey the following year. Data were analyzed with chi (2) and Wilcoxon Signed Rank tests using SPSS.

RESULTS

Surveys were received from 238 residents (20%) in Study 1 and 269 residents in Study 2 (23%, representing 50% of all residency programs). In both studies, residents reported performing significantly less forceps than vacuum deliveries. Virtually all residents wanted to learn to perform both deliveries, indicated attendings were willing to teach both, and felt competent to perform vacuum deliveries (Study 1, 94.5%; Study 2, 98.5%); only half felt competent to perform forceps deliveries (Study 1, 57.6%; Study 2, 55.0%). The majority of residents who felt competent to perform forceps deliveries reported that they would predominately use forceps or both methods of deliveries in their practice (Study 1, 75.8%; Study 2, 64.6%). The majority of residents who reported that they did not feel competent to perform forceps deliveries reported that they would predominately use vacuum deliveries in their practice (Study 1, 86.1%; Study 2, 84.2%).

CONCLUSION

Current training results in a substantial portion of residents graduating who do not feel competent to perform forceps deliveries. Perceived competency affected future operative delivery plans.

Using nanotechnology to improve the characteristics of antineoplastic drugs: Improved characteristics of nab-paclitaxel compared with solvent-based paclitaxel

Nanotechnology refers to the use of very small pieces of matter, typically < or =200 nm in diameter. Nanoparticle albumin-bound (nab) paclitaxel, a soluble form of the cytotoxin paclitaxel that has demonstrated utility in the setting of cancer chemotherapy, is produced by nab technology using the protein albumin. nab-Paclitaxel targets tumors, enhances tumor penetration by the novel mechanism of albumin receptor-mediated (gp60) endothelial transcytosis, and avoids the use of surfactants and solvents such as Cremophor and Tween. nab-Paclitaxel minimizes the toxicities associated with Cremophor and eliminates the need for premedication for hypersensitivity reactions caused by Cremophor. The albumin coating that surrounds the active drug assists in the transport of the nanoparticles to the interior of the tumor cell that preferentially takes in albumin as a nutrient through the gp60 pathway. In nonclinical studies, nab-paclitaxel achieved higher intratumoral concentrations compared with solvent-based paclitaxel and increased the bioavailability of paclitaxel by eliminating the entrapment of paclitaxel in the plasma. Compared with solvent-based paclitaxel, at equitoxic doses, the nab-paclitaxel produced more complete regressions, longer time to recurrence, longer doubling times, and prolonged survival. nab-Paclitaxel has been shown to have superior efficacy compared with solvent-based paclitaxel without the need for premedication in clinical trials of patients with advanced solid tumors. nab-Paclitaxel has been effective in patients for whom previous chemotherapy has not been helpful. nab Technology has the potential to be applied to other insoluble drugs.

A prospective, non-randomised phase 1-2 trial of VACOP-B with filgrastim support for HIV-related non-Hodgkin's lymphoma

Non-Hodgkin's lymphoma (NHL) remains an important complication of associated HIV infection despite advances in antiretroviral therapy (ART), and the optimum chemotherapy regimen for this disease remains to be defined. A dose-escalation trial was performed to determine the maximum tolerated doses of etoposide and doxorubicin as part of the 12-week VACOP-B regimen, supported by filgrastim (r-metHuG-CSF). Patients with aggressive histology HIV-related NHL who were previously untreated with chemotherapy, and who had no active opportunistic infection were eligible for the study. Chemotherapy consisted of cyclophosphamide 350 mg/m2, vincristine 2 mg, bleomycin 10 U/m2; and prednisone 100 mg q2 days x 12 weeks, with increasing doses of doxorubicin 25-50 mg/m2 and etoposide 25-50 mg/m2 intravenously and 50-100 mg/m2 orally. Central nervous system prophylaxis (intrathecal cytarabine 50 mg x 4 doses), antifungal, and Pneumocystis carinii prophylaxis were used, and filgrastim was administered to prevent neutropenic complications. One dose level was expanded to permit the concomitant use of ART. Endpoints were determination of maximum tolerated dose of doxorubicin and etoposide, treatment tolerability, and survival. Forty-seven patients were enrolled, most with diffuse large-cell or immunoblastic NHL. Protocol-defined maximum tolerated dose was not reached and the limits of dose-limiting toxicity were not exceeded, even in patients receiving ART. Thirty-two cycles (4.9%) were delayed >6 days because of toxicity; 30 patients (64%) completed all 12 weeks of treatment. After completion of therapy, 14 patients had a complete response (30%), and 4 had a partial response (8%). Median time to progression was 9 months. At 42 months, progression-free survival was 25% and overall survival was 28%.

Medical writing departments in biopharma companies: how to establish a department

Medical writers have important roles in preparing the documentation for approval for marketing of new products, writing manuscripts for publication, and other nonclinical, clinical, and promotional materials. Medical writing departments can be organized in different ways to accommodate the needs of the company. When organizing a new department or when determining metric for an existing department, it is important to understand what medical writers in the biopharma industry do, how they are recruited and trained, and how metrics are developed.

Using the biologic license application or new drug application as a basis for the common technical document

With the introduction of the common technical document (CTD), many writers in the biotech and pharmaceutical industries are now required to submit dossiers in this format. The format of the CTD is not extremely difficult from the familiar documents of the Biologic License Application (BLA) or New Drug Application (NDA). The CTD can be mapped to existing areas of the BLA or NDA. The components of the CTD are discussed and references to the current guidance worldwide are provided to assist the writer.

Review of current authorship guidelines and the controversy regarding publication of clinical trial data

Publication of clinical trial data is the final step in the scientific method and an important method by which pharmaceutical and biotechnology companies, i.e., drug sponsors, disseminate information about their products. Because of the nature of large, multicenter trials, multiple investigators from many institutions may be considered as authors of these papers. Controversy concerning the rights of academic institutions and the rights of drug sponsors has been widely debated. This chapter summarizes the controversy and the current policies.

Guidelines and policies for medical writers in the biotech industry: An update on the controversy

Papers reporting the results of clinical trials written by medical writers employed by the biotech and pharmaceutical industries have been criticized for possible bias in presentation and failure to adhere to authorship guidelines. Several groups have attempted to address the concerns of journal editors, academics, regulators, and the general public by issuing guidelines and policies for the preparation of such material.

Drug-induced and antibody-mediated pure red cell aplasia: a review of literature and current knowledge

Anti-erythropoietin (EPO)-induced pure red cell aplasia (PRCA) is an uncommon, potentially life-threatening condition in which the bone marrow stops manufacturing red blood cells. In the past few years, reports of drug-induced, anti-EPO antibody-mediated PRCA have increased substantially, with most cases attributed to the use of one erythropoiesis-stimulating protein, Eprex. A literature review was undertaken to document the reports of drug-induced PRCA, with all drugs and drug regimens. The sudden increase in reports of antibody-mediated PRCA is discussed.

The development of supportive-care agents for patients with cancer

As the population ages, a dramatic increase in the number of cases of cancer is expected and the need for supportive-care agents, those used to ameliorate some of the side effects of cancer or its treatment, becomes more urgent. At present, supportive-care products are available and new agents are being developed with novel mechanisms of action or modifications of existing agents that improve performance. Because of the urgent need for such products, efficient development is required to deliver useful products to patients as rapidly as possible. This chapter uses actual examples to illustrate the stages of drug development, phase I through phase 3.

Darbepoetin alfa: a new approach to the treatment of chemotherapy-induced anaemia

Chemotherapy-induced anaemia has important consequences on the quality of life and social function of cancer patients. The finding of erythropoietin (EPO) deficiency in these patients led to the therapeutic development of erythropoietic proteins. Darbepoetin alfa (Aranesp), Amgen Inc, Thousand Oaks, California), a new erythropoietic growth factor, has eight more sialic acids than epoetin alfa. The increased sialic acid content confers a three-fold longer half-life and allows the drug to be administered less frequently than epoetin alfa. Darbepoetin alfa affects the same early haematopoietic cells as epoetin alfa and the endogenous hormone EPO. Preclinical pharmacokinetic studies suggest that the intrinsic pharmacological properties of darbepoetin alfa are comparable to those of epoetin alfa, but that the increased sialic acid content allows for less-frequent administration with superior performance. Darbepoetin alfa has been shown to have safe clinical efficacy in a variety of tumour settings and with several types of chemotherapy.

Production of high-quality marketing applications: strategies for biotechnology companies working with contract research organizations

Many biotechnology and pharmaceutical companies use clinical research organizations (CROs) to assist in the writing and preparation of clinical documents intended for submission to health authorities. Start-up companies often require the expertise of a CRO to prepare their first regulatory documents. Larger or more experienced companies often require CRO staff to assist at times of multiple simultaneous submissions. The timely production of high-quality new drug marketing applications requires close collaborations between the drug company and the CRO. The views of both CRO and industry in ensuring best practices are discussed.

Pharmacologic and cytokine treatment of commonly encountered anemias

Anemia has multiple etiologies: it may be caused by nutritional deficiencies or congenital abnormalities, or it may be associated with a number of conditions, such as chronic kidney disease, cancer, or human immunodeficiency virus (HIV) infection. Anemia is associated with an increase in morbidity and mortality in patients with endstage renal disease, cancer, or HIV infection. Each case of anemia is different, with different causes, clinical consequences, and treatment strategies. Identifying the most appropriate treatment requires an understanding of the etiology of the anemia and investigation of the nature of the causative medical condition. In some cases, such as anemia associated with chronic kidney disease, treatment is well defined and consists of administration of erythropoiesis-stimulating agents, accompanied by iron supplementation where appropriate. In other instances, such as megaloblastic anemia, which may be caused by vitamin or folate deficiency, vitamin supplementation alone may be a clinically appropriate treatment. This article gives an overview of the etiologies and current therapies of the most commonly encountered types of anemia, highlighting both the diverse nature of the condition, and the equally diverse pharmacologic and supportive treatment approaches.

Effects of sampling standardization on estimates of Phanerozoic marine diversification

Global diversity curves reflect more than just the number of taxa that have existed through time: they also mirror variation in the nature of the fossil record and the way the record is reported. These sampling effects are best quantified by assembling and analyzing large numbers of locality-specific biotic inventories. Here, we introduce a new database of this kind for the Phanerozoic fossil record of marine invertebrates. We apply four substantially distinct analytical methods that estimate taxonomic diversity by quantifying and correcting for variation through time in the number and nature of inventories. Variation introduced by the use of two dramatically different counting protocols also is explored. We present sampling-standardized diversity estimates for two long intervals that sum to 300 Myr (Middle Ordovician-Carboniferous; Late Jurassic-Paleogene). Our new curves differ considerably from traditional, synoptic curves. For example, some of them imply unexpectedly low late Cretaceous and early Tertiary diversity levels. However, such factors as the current emphasis in the database on North America and Europe still obscure our view of the global history of marine biodiversity. These limitations will be addressed as the database and methods are refined.

Clinical research strategies in biotechnology

Clinical drug development involves many steps and is extremely costly to the sponsoring company. There is intense pressure on sponsors to be faster, more efficient, and less costly. Sponsors also need to be globally oriented in their drug-development processes. There are several ways in which clinical drug development may be done more quickly and at less cost. These strategies include the use of large contract research organizations (CRO) and site management organizations (SMO). Although there is an estimated 2000 CRO worldwide, the use of SMO is quite limited but growing rapidly. Changes in the US Food and Drug Administration (FDA), especially harmonization between its two divisions Center for Biologics Evaluation and Research (CBER) and Center for Drug Evaluation and Research (CDER), and the use of CRO and SMO will make for interesting and challenging times for sponsors.

Hematopoietic growth factors in cancer chemotherapy

Hematopoietic growth factors have made a significant impact on the treatment of cancer, primarily in the prevention of infections associated with chemotherapy-induced neutropenia, in progenitor cell transplantation, in chemotherapy-induced thrombocytopenia, and in chemotherapy-induced anemia. As seen with this review, our basic understanding of hematopoietic growth factors and their clinical potential continue to expand. Work will need to continue, especially with the new thrombopoietic factors, megakaryocyte growth and developing factor, thrombopoietin, and IL-11, to fully categorize their biology and clinical characteristics.

Megakaryocyte growth and development factor (MGDF): an Mpl ligand and cytokine that regulates thrombopoiesis

Megakaryocyte growth and development factor (MGDF) is a ligand for the Mpl receptor related to thrombopoietin (TPO). MGDF stimulates megakaryocytopoiesis and thrombopoiesis, and is highly selective to cells bearing the Mpl receptor. Studies done in rodents, nonhuman primates, and humans have confirmed that MGDF can increase platelet counts in normal and chemotherapy- or radiotherapy-treated subjects. Platelet function and physiology remain normal after MGDF administration, with no effect on platelet aggregation. Pegylated recombinant human MGDF (PEG-rHuMGDF) was used clinically with initial success. Cancer patients receiving chemotherapy showed dose-dependent increases in platelet counts and increases in bone marrow megakaryocytes. Clinical development of PEG-rHuMGDF was halted owing to the formation of neutralizing antibodies in some patients and normal volunteers who received the drug. The application of exogenous recombinant Mpl ligands should be explored in the setting of randomized clinical trials and the findings extended to mobilization of CD34+ stem cells, ex vivo expansion techniques, and use in platelet abnormalities.

Biopharmaceutical drug development: Filgrastim (r-metHuG-CSF) use in patients with HIV infection

Hematopoietic growth factors are well known to increase neutrophil counts and support the administration of myelotoxic and myelosuppressive therapies, especially chemotherapies. Filgrastim (r-metHuG-CSF) has been used in the setting of HIV disease to treat neutropenia and HIV-associated neutrophil defects. This article reviews the biology, product characteristics, and preclinical and clinical development of Filgrastim. Emphasis is given on the use of Filgrastim in the setting of HIV infection and AIDS.

The use of Filgrastim in AIDS-related neutropenia

Neutropenic individuals are at high risk for bacterial and fungal infections. Filgrastim (r-metHuG-CSF, NEUPOGEN) has been shown to improve chemotherapy-induced neutropenia significantly. Because a high incidence of HIV-infected patients have neutropenia, often associated with myelosuppressive antiretroviral medication, Filgrastim is frequently used as a treatment strategy for this HIV-associated neutropenia. This review summarizes published work related to the use of Filgrastim in HIV-infected patients. Literature bases (EMBASE, MEDLINE, Int. Pharm. Abs., SciSearch, and Aidsline) from 1970 to 1998 were searched for articles describing the relationship of Filgrastim and ANC to bacterial infection rates, bacterial infection outcome, and overall survival. Thirty-five related articles were identified during this search. Filgrastim appears to have a significant role in increasing peripheral ANC and enhancing neutrophil function in patients with HIV infection and AIDS. This may translate into a clinical benefit of delivery of full-dose myelosuppressive antiretroviral therapy and decreased susceptibility to infections and increased survival in this patient population.

Absolute measures of the completeness of the fossil record

Measuring the completeness of the fossil record is essential to understanding evolution over long timescales, particularly when comparing evolutionary patterns among biological groups with different preservational properties. Completeness measures have been presented for various groups based on gaps in the stratigraphic ranges of fossil taxa and on hypothetical lineages implied by estimated evolutionary trees. Here we present and compare quantitative, widely applicable absolute measures of completeness at two taxonomic levels for a broader sample of higher taxa of marine animals than has previously been available. We provide an estimate of the probability of genus preservation per stratigraphic interval, and determine the proportion of living families with some fossil record. The two completeness measures use very different data and calculations. The probability of genus preservation depends almost entirely on the Palaeozoic and Mesozoic records, whereas the proportion of living families with a fossil record is influenced largely by Cenozoic data. These measurements are nonetheless highly correlated, with outliers quite explicable, and we find that completeness is rather high for many animal groups.

Evolutionary and preservational constraints on origins of biologic groups: divergence times of eutherian mammals

Some molecular clock estimates of divergence times of taxonomic groups undergoing evolutionary radiation are much older than the groups' first observed fossil record. Mathematical models of branching evolution are used to estimate the maximal rate of fossil preservation consistent with a postulated missing history, given the sum of species durations implied by early origins under a range of species origination and extinction rates. The plausibility of postulated divergence times depends on origination, extinction, and preservation rates estimated from the fossil record. For eutherian mammals, this approach suggests that it is unlikely that many modern orders arose much earlier than their oldest fossil records.

Filgrastim restores interleukin-2 production in blood from patients with advanced human immunodeficiency virus infection

Filgrastim induces lymphocytosis, including all T cell subsets, and increased ex vivo interleukin (IL)-2 release as well as lymphocyte proliferation. Since Filgrastim is increasingly used in patients with human immunodeficiency virus (HIV) infection, the effect of Filgrastim on ex vivo cytokine production was determined. Whole blood from 8 healthy volunteers, 5 high-risk volunteers, and 31 HIV-infected outpatients was assayed for cytokine production in response to endotoxin (LPS) or staphylococcal enterotoxin B (SEB) in the presence or absence of 100 ng/mL Filgrastim. LPS-inducible blood cytokine release of HIV-infected patients was not different from that of normal or high-risk volunteers. The suppressive effect of Filgrastim on LPS-inducible blood tumor necrosis factor-alpha and interferon-gamma formation in normal volunteers was not found in HIV-infected patients. Patients with advanced HIV infection showed reduced IL-2 and IL-4 release in the presence of SEB. In the presence of Filgrastim, IL-2 production was partially restored.

Managing diabetes through home care

Diabetes management will hold an increasingly larger place in home care services as the population ages. Advocate Home Health Services in Oakbrook, Illinois, has developed a diabetes management program to help people with diabetes live more easily with this chronic disease.