Acute myeloid leukemia is a life-threatening disease associated with high mortality rates. A substantial number of patients require intensive care. This investigation analyzes risk factors predicting ...admission to the intensive care unit in patients with acute myeloid leukemia eligible for induction chemotherapy, the outcome of these patients, and prognostic factors predicting their survival.
A total of 406 consecutive patients with de novo acute myeloid leukemia (15-89 years) were analyzed retrospectively. Markers recorded at the time of diagnosis included karyotype, fibrinogen, C-reactive protein, and Charlson comorbidity index. In patients requiring critical care, the value of the Simplified Acute Physiology Score II, the need for mechanical ventilation, and vasopressor support were recorded at the time of intensive care unit admission. The independent prognostic relevance of the parameters was tested by multivariate analysis.
Sixty-two patients (15.3%) required intensive care, primarily due to respiratory failure (50.0%) or life-threatening bleeding (22.6%). Independent risk factors predicting intensive care unit admission were lower fibrinogen concentration, the presence of an infection, and comorbidity. The survival rate was 45%, with the Simplified Acute Physiology Score II being the only independent prognostic parameter (P<0.05). Survival was inferior in intensive care patients compared to patients not admitted to an intensive care unit. However, no difference between intensive care and non-intensive care patients was found concerning continuous complete remission at 6 years or survival at 6 years in patients who survived the first 30 days after diagnosis (non-intensive care patients: 28%; intensive care patients: 20%, P>0.05).
Ongoing infections, low fibrinogen and comorbidity are predictive for intensive care unit admission in acute myeloid leukemia. Although admission was a risk factor for survival, continuous complete remission and survival of patients alive at day 30 were similar in patients who were admitted or not admitted to an intensive care unit.
Individual variation in drug metabolism is a major cause of unpredictable side effects during therapy. Drug metabolism is controlled by a class of orphan nuclear receptors (NRs), which regulate ...expression of genes such as CYP (cytochrome)3A4 and MDR-1 (multi-drug resistance-1), that are involved in this process. We have found that xenobiotic-mediated induction of CYP3A4 and MDR-1 gene transcription was inhibited by ketoconazole, a commonly used antifungal drug. Ketoconazole mediated its effect by inhibiting the activation of NRs, human pregnenolone X receptor and constitutive androstene receptor, involved in regulation of CYP3A4 and MDR-1. The effect of ketoconazole was specific to the group of NRs that control xenobiotic metabolism. Ketoconazole disrupted the interaction of the xenobiotic receptor PXR with the co-activator steroid receptor co-activator-1. Ketoconazole treatment resulted in delayed metabolism of tribromoethanol anesthetic in mice, which was correlated to the inhibition of PXR activation and downmodulation of cyp3a11 and mdr-1 genes and proteins. These studies demonstrate for the first time that ketoconazole represses the coordinated activation of genes involved in drug metabolism, by blocking activation of a specific subset of NRs. Our results suggest that ketoconazole can be used as a pan-antagonist of NRs involved in xenobiotic metabolism in vivo, which may lead to novel strategies that improve drug effect and tolerance.
Intrinsic apoptosis involves BH3-only protein activation of Bax/Bak-mediated mitochondrial outer membrane permeabilization (MOMP). Consequently, cytochrome c is released from the mitochondria to ...activate caspases, and Smac (second mitochondria-derived activator of caspases) to inhibit XIAP-mediated caspase suppression. Dysfunctional mitochondria can be targeted for lysosomal degradation via autophagy (mitophagy), or directly through mitochondria-derived vesicle transport. However, the extent of autophagy and lysosomal interactions with apoptotic mitochondria remains largely unknown. We describe here a novel pathway of endolysosomal processing of mitochondria, activated in response to canonical BH3-only proteins and mitochondrial depolarization. We report that expression of canonical BH3-only proteins, tBid, BimEL, Bik, Bad, and mitophagy receptor mutants of atypical BH3-only proteins, Bnip3 and Bnip3L/Nix, leads to prominent relocalization of endolysosomes into inner mitochondrial compartments, in a manner independent of mitophagy. As an upstream regulator, we identified the XIAP E3 ligase. In response to mitochondrial depolarization, XIAP actuates Bax-mediated MOMP, even in the absence of BH3-only protein signaling. Subsequently, in an E3 ligase-dependent manner, XIAP rapidly localizes inside all the mitochondria, and XIAP-mediated mitochondrial ubiquitylation catalyses interactions of Rab membrane targeting components Rabex-5 and Rep-1 (RFP-tagged Rab escort protein-1), and Rab5- and Rab7-positive endolysosomes, at and within mitochondrial membrane compartments. While XIAP-mediated MOMP permits delayed cytochrome c release, within the mitochondria XIAP selectively signals lysosome- and proteasome-associated degradation of its inhibitor Smac. These findings suggest a general mechanism to lower the mitochondrial apoptotic potential via intramitochondrial degradation of Smac.
Arterial tissues collected from Ossabaw swine bearing metabolic syndrome-induced cardiovascular plaques are characterized by multimodal nonlinear optical microscopy that allows coherent anti-Stokes ...Raman scattering, second-harmonic generation, and two-photon excitation fluorescence imaging on the same platform. Significant components of arterial walls and atherosclerotic lesions, including endothelial cells, extracellular lipid droplets, lipid-rich cells, low-density lipoprotein aggregates, collagen, and elastin are imaged without any labeling. Emission spectra of these components are obtained by nonlinear optical microspectrometry. The nonlinear optical contrast is compared with histology of the same sample. Multimodal nonlinear optical imaging of plaque composition also allows identification of atherosclerotic regions that are vulnerable to rupture risk. The demonstrated capability of nonlinear optical microscopy for label-free molecular imaging of atherosclerotic lesions with 3-D submicrometric resolution suggests its potential application to the diagnosis of atherosclerotic plaques, determination of their rupture risk, and design of individualized drug therapy based on plaque composition.
SCF
ubiquitinates Thr187-phosphorylated p27 for degradation. Overexpression of Skp2 coupled with underexpression of p27 are frequent characteristics of cancer cells. When the role of SCF
-mediated ...p27 ubiquitination in cancer was specifically tested by p27 Thr187-to-Ala knockin (p27T187A KI), it was found dispensable for Kras
-induced lung tumorigenesis but essential for Rb1-deficient pituitary tumorigenesis. Here we identify pRb and p53 doubly deficient (DKO) prostate tumorigenesis as a context in which p27 ubiquitination by SCF
is required for p27 downregulation. p27 protein accumulated in prostate when p27T187A KI mice underwent DKO prostate tumorigenesis. p27T187A KI or Skp2 knockdown (KD) induced similar degrees of p27 protein accumulation in DKO prostate cells, and Skp2 KD did not further increase p27 protein in DKO prostate cells that contained p27T187A KI (AADKO prostate cells). p27T187A KI activated an E2F1-p73-apoptosis axis in DKO prostate tumorigenesis, slowed disease progression and significantly extended survival. Querying co-occurrence relationships among RB1, TP53, PTEN, NKX3-1 and MYC in TCGA of prostate cancer identified co-inactivation of RB1 and TP53 as the only statistically significant co-occurrences in metastatic castration-resistant prostate cancer (mCRPC). Together, our study identifies Skp2/Cks1 pocket inhibitors as potential therapeutics for mCRPC. Procedures for establishing mCRPC organoid cultures from contemporary patients were recently established. An Skp2/Cks1 pocket inhibitor preferentially collapsed DKO prostate tumor organoids over AADKO organoids, which spontaneously disintegrated over time when DKO prostate tumor organoids grew larger, setting the stage to translate mouse model findings to precision medicine in the clinic on the organoid platform.
Cellular membranes ensure functional compartmentalization by dynamic fusion-fission remodeling and are often targeted by viruses during entry, replication, assembly, and egress. Nucleocytoplasmic ...large DNA viruses (NCLDVs) can recruit host-derived open membrane precursors to form their inner viral membrane. Using complementary three-dimensional (3D)-electron microscopy techniques, including focused-ion beam scanning electron microscopy and electron tomography, we show that the giant Mollivirus sibericum utilizes the same strategy but also displays unique features. Indeed, assembly is specifically triggered by an open cisterna with a flat pole in its center and open curling ends that grow by recruitment of vesicles never reported for NCLDVs. These vesicles, abundant in the viral factory (VF), are initially closed but open once in close proximity to the open curling ends of the growing viral membrane. The flat pole appears to play a central role during the entire virus assembly process. While additional capsid layers are assembled from it, it also shapes the growing cisterna into immature crescent-like virions and is located opposite to the membrane elongation and closure sites, thereby providing virions with a polarity. In the VF, DNA-associated filaments are abundant, and DNA is packed within virions prior to particle closure. Altogether, our results highlight the complexity of the interaction between giant viruses and their host. Mollivirus assembly relies on the general strategy of vesicle recruitment, opening, and shaping by capsid layers similar to all NCLDVs studied until now. However, the specific features of its assembly suggest that the molecular mechanisms for cellular membrane remodeling and persistence are unique.
Since the first giant virus
was identified, other giant representatives are isolated regularly around the world and appear to be unique in several aspects. They belong to at least four viral families, and the ways they interact with their hosts remain poorly understood. We focused on Mollivirus sibericum, the sole representative of "Molliviridae," which was isolated from a 30,000-year-old permafrost sample and exhibits spherical virions of complex composition. In particular, we show that (i) assembly is initiated by a unique structure containing a flat pole positioned at the center of an open cisterna, (ii) core packing involves another cisterna-like element seemingly pushing core proteins into particles being assembled, and (iii) specific filamentous structures contain the viral genome before packaging. Altogether, our findings increase our understanding of how complex giant viruses interact with their host and provide the foundation for future studies to elucidate the molecular mechanisms of Mollivirus assembly.
To assess survival in cancer patients admitted to an intensive care unit (ICU) with respect to the nature of malignancy, cause of ICU admittance, and course during ICU stay as well as to evaluate the ...prognostic value of the Acute Physiology and Chronic Health Evaluation (APACHE) III score.
Retrospective cohort study.
ICU at a university cancer referral center.
A total of 414 cancer patients admitted to the ICU during a period of 66 months.
None.
Charts of the patients were analyzed with respect to underlying disease, cause of admission, APACHE III score, need and duration of mechanical ventilation, neutropenia and development of septic shock, as well as ICU survival and survival after discharge. Mortality data were compared with two control groups: 1362 patients admitted to our ICU suffering from diseases other than cancer and 2,776 cancer patients not admitted to the ICU.
ICU survival was 53%, and 1-yr survival was 23%. The 1-yr mortality rate was significantly lower in both control groups. Patients admitted after bone marrow transplantation had the highest mortality. In a multivariate analysis, prognosis was negatively influenced by respiratory insufficiency, the need of mechanical ventilation, and development of septic shock during the ICU stay. Admission after cardiopulmonary resuscitation yielded high ICU mortality but a relatively good long-term prognosis. Admission after surgery and as a result of acute hemorrhage was associated with a good prognosis. Age, neutropenia, and underlying disease did not influence outcome significantly. Admission APACHE III scores were significantly higher in nonsurvivors but failed to predict individual outcome satisfactorily. All patients with APACHE III scores of >80 died at the ICU.
A combination of factors must be taken into account to estimate a critically ill cancer patient's prognosis in the ICU. The APACHE III scoring system alone should not be used to make decisions about therapy prolongation. Admission to the ICU worsens the prognosis of a cancer patient substantially; however, as ICU mortality is 47%, comparable with severely ill noncancer patients, general reluctance to admit cancer patients to an ICU does not seem to be justified.
Vaccinia virus (vv), a member of the poxvirus family, is unique among most DNA viruses in that its replication occurs in the cytoplasm of the infected host cell. Although this viral process is known ...to occur in distinct cytoplasmic sites, little is known about its organization and in particular its relation with cellular membranes. The present study shows by electron microscopy (EM) that soon after initial vv DNA synthesis at 2 h postinfection, the sites become entirely surrounded by membranes of the endoplasmic reticulum (ER). Complete wrapping requires ~45 min and persists until virion assembly is initiated at 6 h postinfection, and the ER dissociates from the replication sites. (3)HThymidine incorporation at different infection times shows that efficient vv DNA synthesis coincides with complete ER wrapping, suggesting that the ER facilitates viral replication. Proteins known to be associated with the nuclear envelope in interphase cells are not targeted to these DNA-surrounding ER membranes, ruling out a role for these molecules in the wrapping process. By random green fluorescent protein-tagging of vv early genes of unknown function with a putative transmembrane domain, a novel vv protein, the gene product of E8R, was identified that is targeted to the ER around the DNA sites. Antibodies raised against this vv early membrane protein showed, by immunofluorescence microscopy, a characteristic ring-like pattern around the replication site. By electron microscopy quantitation the protein concentrated in the ER surrounding the DNA site and was preferentially targeted to membrane facing the inside of this site. These combined data are discussed in relation to nuclear envelope assembly/disassembly as it occurs during the cell cycle.
Percutaneous cricothyroidotomy is a lifesaving procedure for airway obstruction in trauma victims who need airway establishment and cannot be intubated or in whom intubation has failed.
The purpose ...of this study was to examine whether there is a training effect using Seldinger technique emergency cricothyroidotomy (group 1; Arndt Emergency Cricothyroidotomy Catheter Set; Cook Critical Care, Bloomington, IN) versus standard surgical cricothyroidotomy (group 2). Twenty emergency physicians performed five cricothyroidotomies with each method in a total of 200 human cadavers, comparing efficacy and safety (speed, success rate, and injuries).
Seven attempts in group 1 and six in group 2 had to be aborted. Time intervals from the start of the procedure to location of the cricothyroid membrane were not significantly different between the groups. However, time to tracheal puncture (P < 0.01) and time to first ventilation (P < 0.001) were significantly longer in group 2. No time effect could be observed in both groups. The airway was accurately placed into the trachea through the cricothyroid membrane in 88.2% (82 of 93) of the cadavers in group 1 and in 84.0% (79 of 94) in group 2 (not significant). No injuries were observed in group 1, whereas there were six punctures of the thyroid vessels in group 2 (P < 0.05).
With respect to time needed for the procedure, the participants performed Seldinger technique emergency cricothyroidotomy significantly faster as compared with standard surgical cricothyroidotomy. Even if no training effect had been observed, the authors believe that it is important to train residents in different methods of cricothyroidotomy in cadavers in addition to training in mannequins to achieve a higher level of efficacy in real-life situations. The shorter time to first ventilation and the fact that no injuries could be observed favor the Seldinger technique.
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