269 research outputs found
Mechanism-based model characterizing bidirectional interaction between PEGylated liposomal CKD-602 (S-CKD602) and monocytes in cancer patients
S-CKD602 is a PEGylated liposomal formulation of CKD-602, a potent topoisomerase I inhibitor. The objective of this study was to characterize the bidirectional pharmacokinetic-pharmacodynamic (PK-PD) interaction between S-CKD602 and monocytes. Plasma concentrations of encapsulated CKD-602 and monocytes counts from 45 patients with solid tumors were collected following intravenous administration of S-CKD602 in the phase I study. The PK-PD models were developed and fit simultaneously to the PK-PD data, using NONMEM®. The monocytopenia after administration of S-CKD602 was described by direct toxicity to monocytes in a mechanism-based model, and by direct toxicity to progenitor cells in bone marrow in a myelosuppression-based model. The nonlinear PK disposition of S-CKD602 was described by linear degradation and irreversible binding to monocytes in the mechanism-based model, and Michaelis-Menten kinetics in the myelosuppression-based model. The mechanism-based PK-PD model characterized the nonlinear PK disposition, and the bidirectional PK-PD interaction between S-CKD602 and monocytes. © 2012 Cárdenas et al, publisher and licensee Dove Medical Press Ltd
Toxic Epidermal Necrolysis after Pemetrexed and Cisplatin for Non-Small Cell Lung Cancer in a Patient with Sharp Syndrome
Background: Pemetrexed is an antifolate drug approved for maintenance and second-line therapy, and, in combination with cisplatin, for first-line treatment of advanced nonsquamous non-small cell lung cancer. The side-effect profile includes fatigue, hematological and gastrointestinal toxicity, an increase in hepatic enzymes, sensory neuropathy, and pulmonary and cutaneous toxicity in various degrees. Case Report: We present the case of a 58-year-old woman with history of Sharp's syndrome and adenocarcinoma of the lung, who developed toxic epidermal necrolysis after the first cycle of pemetrexed, including erythema, bullae, extensive skin denudation, subsequent systemic inflammation and severe deterioration in general condition. The generalized skin lesions occurred primarily in the previous radiation field and responded to immunosuppressive treatment with prednisone. Conclusion: Although skin toxicity is a well-known side effect of pemetrexed, severe skin reactions after pemetrexed administration are rare. Caution should be applied in cases in which pemetrexed is given subsequent to radiation therapy, especially in patients with pre-existing skin diseases
Outcomes Associated with Brain Metastases in a Three-Arm Phase III Trial of Gemcitabine-Containing Regimens Versus Paclitaxel Plus Carboplatin for Advanced Non-small Cell Lung Cancer
BACKGROUND: Brain metastases (BMs) are a common complication of non-small cell lung cancer (NSCLC). Because of historical data indicating a poor prognosis for patients with BM, few randomized phase III studies of advanced NSCLC have included patients with BM at presentation. Because the potential benefits of systemic therapy in patients with BM are uncertain, we analyzed data from a recent phase III study.
METHODS: One thousand one hundred thirty-five chemonaïve patients with stage IIIB/IV NSCLC were randomized to receive gemcitabine/carboplatin, gemcitabine/paclitaxel, or paclitaxel/carboplatin. Stratification was based on presence or absence of BM, stage, and baseline weight loss. Patients with BM were required to be clinically stable after treatment with radiotherapy or surgery before entry. Results were retrospectively analyzed by presence or absence of BM at study entry.
RESULTS: Rate of BM was 17.1% overall. The response rate was 28.9% for patients with BM (n = 194) versus 29.1% without BM (n = 941). Time to progression was 4.3 months with BM and 4.6 months without BM (p = 0.03). Median survival was 7.7 months (95% confidence interval: 6.7-9.3) among patients with BM (n = 194) and 8.6 months (95% confidence interval: 7.9-9.5) for patients without BM (n = 941), p = 0.09. Rates of hematologic adverse events were not different among patients with and without BM.
CONCLUSIONS: There were no significant differences in response, survival, or hematologic toxicity for patients with or without BM; however, patients with BM had a small but significantly shorter time to progression. Nonprogressing patients with treated BM are appropriate candidates for systemic therapy and entry into clinical trials
Spinal involvement in mucopolysaccharidosis IVA (Morquio-Brailsford or Morquio A syndrome): presentation, diagnosis and management.
Mucopolysaccharidosis IVA (MPS IVA), also known as Morquio-Brailsford or Morquio A syndrome, is a lysosomal storage disorder caused by a deficiency of the enzyme N-acetyl-galactosamine-6-sulphate sulphatase (GALNS). MPS IVA is multisystemic but manifests primarily as a progressive skeletal dysplasia. Spinal involvement is a major cause of morbidity and mortality in MPS IVA. Early diagnosis and timely treatment of problems involving the spine are critical in preventing or arresting neurological deterioration and loss of function. This review details the spinal manifestations of MPS IVA and describes the tools used to diagnose and monitor spinal involvement. The relative utility of radiography, computed tomography (CT) and magnetic resonance imaging (MRI) for the evaluation of cervical spine instability, stenosis, and cord compression is discussed. Surgical interventions, anaesthetic considerations, and the use of neurophysiological monitoring during procedures performed under general anaesthesia are reviewed. Recommendations for regular radiological imaging and neurologic assessments are presented, and the need for a more standardized approach for evaluating and managing spinal involvement in MPS IVA is addressed
Seven-tesla magnetic resonance imaging of the nervus terminalis, olfactory tracts, and olfactory bulbs in COVID-19 patients with anosmia and hypogeusia
Introduction: Linking olfactory epithelium to the central nervous system are cranial nerve 1, the olfactory nerve, and cranial nerve “0,” and the nervus terminalis (NT). Since there is minimal expression of angiotensin-converting enzyme-2 (ACE-2) in the olfactory nerve, it is unclear how SARS-CoV-2 causes anosmia (loss of smell) and hypogeusia (reduction of taste). In animal models, NT expresses ACE-2 receptors, suggesting a possible SARS-CoV-2 viral entry site in humans. The purpose of this study was to determine whether ultra-high-field 7 T magnetic resonance imaging (MRI) could visualize the NT, olfactory bulbs (OB), and olfactory tract (OT) in healthy controls and COVID-19 anosmia or hypogeusia and to qualitatively assess for volume loss and T2 alterations.
Methods: In this study, 7 T MRI was used to evaluate the brain and olfactory regions in 45 COVID-19 patients and 29 healthy controls. Neuroimaging was qualitatively assessed by four board-certified neuroradiologists who were blinded to outcome assignments: for the presence or absence of NT; for OB, OT, and brain volume loss; and altered T2 signal, white matter T2 hyperintensities, microhemorrhages, enlarged perivascular spaces, and brainstem involvement.
Results: NT was identifiable in all COVID-19 patients and controls. T2 hyperintensity in the NT, OB, and OT in COVID-19 patients with anosmia or hypogeusia was statistically significant compared to controls and COVID-19 patients without anosmia or hypogeusia.
Discussion: On 7 T MRI, NT was radiographically identifiable, adjacent to OB and OT. In COVID-19 anosmia and hypogeusia, T2 hyperintensity of NT, OB, and OT was statistically significant compared to COVID-19 patients without anosmia or hypogeusia and controls. The NT may be a potential entry site for SARs-CoV-2 and may play a role in the pathophysiology of COVID-19 anosmia
Rivaroxaban for Preventing Venous Thromboembolism in High-Risk Ambulatory Patients with Cancer: Rationale and Design of the CASSINI Trial
Venous thromboembolism (VTE) is a frequent complication of cancer associated with morbidity, mortality, increased hospitalizations and higher health care costs. Cancer patients at increased risk for VTE can be identified using a validated risk assessment score, and the incidence of VTE can be reduced in high-risk settings using anticoagulation. Rivaroxaban is a potent, oral, direct, factor Xa inhibitor approved for the prevention and treatment of thromboembolic events, including VTE. CASSINI is a double-blind, randomized, parallel-group, multicentre study comparing rivaroxaban with placebo in adult ambulatory patients with various cancers who are initiating systemic cancer therapy and are at high risk of VTE (Khorana score ≥ 2). Patients with primary brain tumours or those at risk for bleeding are excluded. Approximately 700 patients will be randomized 1:1 to rivaroxaban 10 mg daily or placebo for up to 6 months if there is no evidence of VTE from compression ultrasonography (CU) during screening or from routine care imaging within 30 days prior to randomization. Mandatory CU will also be performed at weeks 8 and 16 (±7 days), and at study end (±3 days). The primary efficacy hypothesis is that anticoagulation with rivaroxaban reduces the composite of objectively confirmed symptomatic or asymptomatic, lower-extremity, proximal deep-vein thrombosis (DVT); symptomatic, upper-extremity DVT; symptomatic or incidental pulmonary embolism; and VTE-related death compared with placebo. The primary safety objective is to assess major bleeding events (Clinical trial information: NCT02555878)
Human variation databases
More than 100 000 human genetic variations have been described in various genes that are associated with a wide variety of diseases. Such data provides invaluable information for both clinical medicine and basic science. A number of locus-specific databases have been developed to exploit this huge amount of data. However, the scope, format and content of these databases differ strongly and as no standard for variation databases has yet been adopted, the way data is presented varies enormously. This review aims to give an overview of current resources for human variation data in public and commercial resources
Neutron Majorana mass from exotic instantons
We show how a Majorana mass for the Neutron could result from
non-perturbative quantum gravity effects peculiar to string theory. In
particular, "exotic instantons" in un-oriented string compactifications with
D-branes extending the (supersymmetric) standard model could indirectly produce
an effective operator delta{m} n^t n+h.c. In a specific model with an extra
vector-like pair of `quarks', acquiring a large mass proportional to the string
mass scale (exponentially suppressed by a function of the string moduli
fields), delta{m} can turn out to be as low as 10^{-24}-10^{-25} eV. The
induced neutron-antineutron oscillations could take place with a time scale
tau_{n\bar{n}} > 10^8 s, that could be tested by the next generation of
experiments. On the other hand, proton decay and FCNC's are automatically
strongly suppressed and are compatible with the current experimental limits.
Depending on the number of brane intersections, the model may also lead to the
generation of Majorana masses for R-handed neutrini. Our proposal could also
suggest neutron-neutralino or neutron-axino oscillations, with implications in
UCN, Dark Matter Direct Detection, UHECR and Neutron-Antineutron oscillations.
This suggests to improve the limits on neutron-antineutron oscillations, as a
possible test of string theory and quantum gravity.Comment: 35 pages, 11 figures. More comments on neutron-neutralino mixin
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