Uncovering NOTCH1 as a Promising Target in the Treatment of MLL-Rearranged Leukemia.

MLL rearrangement (MLLr) is responsible for the development of acute leukemias with poor outcomes. Therefore, new therapeutic approaches are urgently needed. The NOTCH1 pathway plays a critical role in the pathogenesis of many cancers including acute leukemia. Using a CRISPR/Cas9 MLL-AF4/-AF9 translocation model, the newly developed NOTCH1 inhibitor CAD204520 with less toxic side effects allowed us to unravel the impact of NOTCH1 as a pathogenic driver and potential therapeutic target in MLLr leukemia. RNA sequencing (RNA-seq) and RT-qPCR of our MLLr model and MLLr cell lines showed the NOTCH1 pathway was overexpressed and activated. Strikingly, we confirmed this elevated expression level in leukemia patients. We also demonstrated that CAD204520 treatment of MLLr cells significantly reduces NOTCH1 and its target genes as well as NOTCH1 receptor expression. This was not observed with a comparable cytarabine treatment, indicating the specificity of the small molecule. Accordingly, treatment with CAD204520 resulted in dose-dependent reduced proliferation and viability, increased apoptosis, and the induction of cell cycle arrest via the downregulation of MLL and NOTCH1 target genes. In conclusion, our findings uncover the oncogenic relevance of the NOTCH1 pathway in MLLr leukemia. Its inhibition leads to specific anti-leukemic effects and paves the way for further evaluation in clinical settings.

AGEP from a dog bite treated with Ibuprofen.

BACKGROUND: Acute Generalized Exanthematous Pustulosis (AGEP) is a rare dermatologic reaction characterized by an erythematous rash with pustular erosions, fever and leukocytosis. Although most often secondary to antibiotic use, AGEP has also been associated with many drugs. A thorough literature search showed only four previously documented cases of ibuprofen-associated AGEP, and one case of dog bite-associated AGEP. CASE REPORT: We present the case of a 46 year old Caucasian female who developed AGEP after self-treating with ibuprofen for a dog bite. CONCLUSION: In the clinical setting this rash is often dramatic and illuminating the causative agent can be a diagnostic challenge. Our case represents a rare cause of AGEP and an important finding for current practitioners.

Physical exercise induces specific adaptations resulting in reduced organ injury and mortality during severe polymicrobial sepsis.

OBJECTIVES: High physical activity levels are associated with wide-ranging health benefits, disease prevention, and longevity. In the present study, we examined the impact of regular physical exercise on the severity of organ injury and survival probability, as well as characteristics of the systemic immune and metabolic response during severe polymicrobial sepsis. DESIGN: Animal study. SETTING: University laboratory. SUBJECTS: Male C57BL/6N mice. INTERVENTIONS: Mice were trained for 6 weeks by treadmill and voluntary wheel running or housed normally. Polymicrobial sepsis in mice was induced by injection of fecal slurry. Subsequently, mice were randomized into the following groups: healthy controls, 6 hours postsepsis, and 24 hours postsepsis. MEASUREMENTS AND MAIN RESULTS: Blood and organ samples were collected and investigated by measuring clinical chemistry variables, cytokines, plasma metabolites, and bacterial clearance. Organ morphology and damage were characterized by histological staining. Physical exercise improved survival and the ability of bacterial clearance in blood and organs. The release of pro- and anti-inflammatory cytokines, including interleukin-6 and interleukin-10, was diminished in trained compared to untrained mice during sepsis. The sepsis-associated acute kidney tubular damage was less pronounced in pretrained animals. By metabolic profiling and regression analysis, we detected lysophosphatidylcholine 14:0, tryptophan, as well as pimelylcarnitine linked with levels of neutrophil gelatinase-associated lipocalin representing acute tubular injury (corrected R=0.910; p<0.001). We identified plasma lysophosphatidylcholine 16:0, lysophosphatidylcholine 17:0, and lysophosphatidylcholine 18:0 as significant metabolites discriminating between trained and untrained mice during sepsis. CONCLUSIONS: Regular physical exercise reduces sepsis-associated acute kidney injury and death. As a specific mechanism of exercise-induced adaptation, we identified various lysophosphatidylcholines that might function as surrogate for improved outcome in sepsis.

Intravascular Large B Cell Lymphoma - Still a Diagnostic Dilemma.

Intravascular large B cell lymphoma (IVLBCL), a rare subtype of diffuse large B cell lymphoma (DLBCL), presents with non-specific symptoms and is an extremely difficult diagnosis to make despite extensive workup. It very rarely presents with endocrinologic abnormalities. We present a case of an 81-year-old woman whose predominant presenting manifestation was endocrinopathy, who passed away from multiorgan failure, and was diagnosed to have IVLBCL on post mortem autopsy.

Pre- and postsynaptic localization of the 5-HT7 receptor in rat dorsal spinal cord: immunocytochemical evidence.

Several lines of evidence indicate that 5-HT7 receptors are involved in pain control at the level of the spinal cord, although their mechanism of action is poorly understood. To provide a morphological basis for understanding the action of 5-HT on this receptor, we performed an immunocytochemical study of 5-HT7 receptor distribution at the lumbar level. 5-HT7 immunolabelling is localized mainly in the two superficial laminae of the dorsal horn and in small and medium-sized dorsal root ganglion cells, which is consistent with a predominant role in nociception. In addition, moderate labelling is found in the lumbar dorsolateral nucleus (Onuf's nucleus), suggesting involvement in the control of pelvic floor muscles. Electron microscopic examination of the dorsal horn revealed three main localizations: 1) a postsynaptic localization on peptidergic cell bodies in laminae I-III and in numerous dendrites; 2) a presynaptic localization on unmyelinated and thin myelinated peptidergic fibers (two types of axon terminals are observed, large ones, presumably of primary afferent origin, and smaller ones partially from intrinsic cells; this presynaptic labelling represents 60% and 22% of total labelling in laminae I and II, respectively); and 3) 16.9% of labelling in lamina I and 19.8% in lamina II are observed in astrocytes. Labeled astrocytes are either intermingled with neuronal elements or make astrocytic "feet" on blood vessels. In dendrites, the labelling is localized on synaptic differentiations, suggesting that 5-HT may act synaptically on the 5-HT7 receptor. This localization is compared with other 5-HT receptor localizations, and their physiological consequences are discussed.

Association of clinical signs and symptoms of Ebola viral disease with case fatality: a systematic review and meta-analysis.

BACKGROUND: Ebola virus disease (EVD) is a public health emergency of international concern. There is limited laboratory and clinical data available on patients with EVD. This is a meta-analysis to assess the utility of clinical signs, symptoms, and laboratory data in predicting mortality in EVD. AIM: To assess the utility of clinical signs, symptoms, and laboratory data in predicting mortality in EVD. METHOD: Study selection criterion: EVD articles with more than 35 EVD cases that described the clinical features were included. Data collection and extraction: Articles were searched in Medline, PubMed, Ovid journals, and CDC and WHO official websites. STATISTICAL METHODS: Pooled proportions were calculated using DerSimonian Laird method (random effects model). RESULTS: Initial search identified 634 reference articles, of which 67 were selected and reviewed. Data were extracted from 10 articles (N=5,792) of EVD which met the inclusion criteria. Bleeding events (64.5% vs. 25.1%), abdominal pain (58.3% vs. 37.5%), vomiting (60.8% vs. 31.7%), diarrhea (69.9% vs. 37.8%), cough (31.6% vs. 22.3%), sore throat (47.7% vs. 19.8%), and conjunctivitis (39.3% vs. 20.3%) were more often present in pooled proportion of fatal cases as compared to EVD survivors. CONCLUSIONS: Clinical features of EVD that may be associated with higher mortality include bleeding events, vomiting, diarrhea, abdominal pain, cough, sore throat, and conjunctivitis. These patients should be identified promptly, and appropriate management should be instituted immediately.

5-HT5A receptor localization in the rat spinal cord suggests a role in nociception and control of pelvic floor musculature.

The 5-HT5A receptor is a seven-transmembrane receptor negatively coupled to adenylate cyclase, whose activation opens K+ channels. The 5-HT5A receptor may thus exert an inhibitory effect on neuronal activity. However, the function of this receptor is still largely unknown, in particular at the spinal level, and this is partly due to lack of specific ligands. Immunocytochemistry using specific anti-5-HT5A antibodies reveals a particularly dense labeling in the two superficial layers of the dorsal horn, suggesting that the 5-HT5A receptor may be involved in the spinal modulation of pain. In addition, a very intense staining in the lumbar dorsolateral nucleus (Onuf nucleus) in both males and females suggests that the 5-HT5A receptor is also involved in micturition through the control of urethral sphincter muscles. Colchicine pretreatment allows the staining of numerous cell bodies in lamina II. Fewer labeled cell bodies are seen in laminae I and III-VI, in the lateral spinal nucleus, and in lamina X. Electron microscope examination of 5-HT5A receptor immunoreactivity in spinal cords from untreated animals confirmed the postsynaptic labeling in all regions studied (dorsal horn, dorsolateral nucleus, and lamina X). The morphological heterogeneity of labeled dorsal horn cell bodies suggests that they belong to functionally distinct neurons (projection neurons and interneurons). In the lumbar dorsolateral nucleus, the labeling is preferentially localized on dendrites, suggesting that in this nucleus 5-HT preferentially acts at the dendritic level. Finally, the dense labeling of postsynaptic specializations suggests that the receptor may be in stock before being addressed to the synaptic differentiation.

The 5-HT2A receptor is widely distributed in the rat spinal cord and mainly localized at the plasma membrane of postsynaptic neurons.

Serotonin (5-HT) plays a major role at the spinal level by modulating most spinal functions through several receptor subtypes including the 5-HT2A receptor. To gain further insight into the cellular role of this receptor, we performed an immunocytochemical study of 5-HT2A receptors in the rat spinal cord, at light and electron microscope levels. The results showed that 5-HT2A receptors were widely distributed in the spinal cord at all segmental levels. Immunolabeling was particularly dense in lamina IX and in the dorsal horn lamina IIi. Immunoreactive cell bodies were numerous in lamina IX, where many but not all motoneurons were labeled, as shown by double labeling with choline acetyltransferase antibodies. Stained cell bodies were also observed in the gray matter. The study at the ultrastructural level focused on the lumbar dorsal horn (laminae I-II) and ventral horn (lamina IX). At both levels, 5-HT2A immunoreactivity was mainly postsynaptic on dendrites and cell bodies. However, a little presynaptic labeling was also observed in axon and axon terminals, some of them containing large granular vesicles attesting to their peptidergic nature. The main result of our study was the "nonsynaptic" plasma membrane localization of 5-HT2A receptors covering a large surface of cell bodies and dendrites, suggesting a paracrine form of action of serotonin. These observations are consistent with a double role (pre- and postsynaptic) for serotonin on these receptors on various cellular targets.

The vanilloid receptor-1 (TRPV1) is expressed in some rat dorsal horn NK1 cells.

The vanilloid receptor-1 (TRPV1), the capsaicin receptor, a transducer of several nociceptive stimuli, is principally expressed by nociceptive fibers that specifically target supraspinal-projecting neurons expressing the NK1 receptor. TRPV1 is also expressed by intraspinal neurons. Using double immunocytochemistry, we show that 14.2% of these TRPV1 dorsal horn cell bodies also express the NK1 receptor suggesting that endogenous vanilloids may directly modulate second-order ascending neurons.

Pharmacological properties of peptides derived from an antibody against the tachykinin NK1 receptor for the neuropeptide substance P.

Two peptides were derived from the structural analysis of a previously described monoclonal antibody [Mol. Immunol. 37 (2000) 423] against the tachykinin NK(1) receptor for the neuropeptide substance P. Here we show that these two peptides were able to inhibit the inositol phosphate transduction pathway triggered both by substance P and neurokinin A, another high-affinity endogenous ligand for the tachykinin NK(1) receptor. They also reduced the cAMP production induced by substance P. By contrast, only one antagonist peptide was able to prevent substance P and neurokinin A from binding the receptor, as revealed both by biochemical and autoradiographic studies. First, these results illustrate the generality of the antibody-based strategy for developing new bioactive peptides. Second, they indicate that antagonists, even exhibiting very close amino acid composition, can interact with the tachykinin NK(1) receptor at different contact sites, some of them clearly distinct from the contact domains for endogenous agonists.

The vanilloid receptor-1 is expressed in rat spinal dorsal horn astrocytes.

The vanilloid receptor-1 (TRPV1), expressed by nociceptive fibers, is a transducer of thermal and chemical nociceptive messages. However, endogenous ligands excite TRPV1 receptors localized on central nociceptive terminals and interneurons. Using immunocytochemistry at the ultrastructural level, we show that TRPV1 is also expressed in spinal glial cells characterized as astrocyte by double labeling with glial fibrillary acid protein. Quantification of the labeling shows that the most numerous labeling is neuronal and that 7% of the total TRPV1 labeling is localized in astrocytes. The total absence of staining in TRPV1 knock out mice strongly suggests that true TRPV1 protein is present in astrocytes. The localization of TRPV1-containing astrocytes apposed to nociceptive C-terminals suggests that they may be involved in the control of pain transmission.

Neuronal and astrocytic localization of the cannabinoid receptor-1 in the dorsal horn of the rat spinal cord.

Cannabinoids are involved in the control of pain at the spinal level through the cannabinoid receptor-1 (CB1) localized pre- and postsynaptically on primary afferent fibres and dorsal horn interneurones, respectively. Using immunocytochemistry, we show that in addition to its neuronal localization, CB1 is also expressed in numerous astrocytes in laminae I and II of the rat dorsal horn. This ubiquitous localization may account for the complex role played by cannabinoids in antinociception. CB1 receptors in astrocytes may be involved in the anti-hyperalgesic action of exogenous cannabinoids.

South Beach Diet associated ketoacidosis: a case report.

INTRODUCTION: It has been previously unclear whether a "mild" degree of low carbohydrate or "starvation" ketonemia and acidosis induced by a low carbohydrate diet is clinically relevant to a patient. CASE PRESENTATION: A 30-year-old Caucasian male on a low carbohydrate diet presented with nausea, vomiting and abdominal pain. The patient's bicarbonate level was 12 and he had hyperglycemia and ketonemia. He was felt to be in diabetic ketoacidosis and was started on intravenous insulin and isotonic saline infusions and responded well. Following cessation of insulin therapy, the patient remained normoglycemic for the remainder of his hospital stay. He later admitted to having been on the South Beach Diet, which is a low carbohydrate diet, for the three weeks prior to his presentation and during which time he had lost 16 pounds. On admission his BMI was 27.1. On presentation, the patient was felt to be in diabetic ketoacidosis but, interestingly, he was subsequently euglycemic without therapy. Following discharge, the patient discontinued the diet plan and he has remained asymptomatic and euglycemic over the following two years. CONCLUSION: The hyperglycemic ketoacidosis in this patient may have been caused by increased concentrations of free fatty acids in the absence of carbohydrate-induced inhibition of beta-oxidation of fatty acids and in the presence of an abnormally high ratio of glucagons to insulin. Given the present day popularity of low-carbohydrate diet plans, healthcare providers should be aware of the apparent association between such diets and symptomatic ketoacidosis. In a patient with ketoacidosis suspected to be secondary to a low carbohydrate diet, all other causes of high anion gap acidosis should be ruled out before attributing the acidosis to the low carbohydrate diet.

Benzocaine and lidocaine induced methemoglobinemia after bronchoscopy: a case report.

INTRODUCTION: Methemoglobinemia is a rare cause of hypoxemia, characterized by abnormal levels of oxidized hemoglobin that cannot bind to and transport oxygen. CASE PRESENTATION: A 62-year-old male underwent bronchoscopy where lidocaine oral solution and Hurricaine spray (20% benzocaine) were used. He developed central cyanosis and his oxygen saturation was 85% via pulse oximetry. An arterial blood gas revealed pH 7.45, PCO2 42, PO2 282, oxygen saturation 85%. Co-oximetry performed revealed a methemoglobin level of 17.5% (normal 0.6-2.5%). The patient was continued on 15 L/minute nonrebreathing face mask and subsequent oxygen saturation improved to 92% within two hours. With hemodynamic stability and improved SpO2, treatment with methylene blue was withheld. CONCLUSION: Methemoglobinemia is a potentially lethal condition after exposure to routinely used drugs. Physicians should be aware of this complication for early diagnosis and treatment.

Serotonin 5-HT2A receptor involvement and Fos expression at the spinal level in vincristine-induced neuropathy in the rat.

We recently showed that peripheral and spinal 5-HT2A receptors (5-HT2AR) are involved in a rodent model of neuropathy induced by a nucleoside analogue reverse transcriptase inhibitor. In this paper, we show that 5-HT2AR are also involved in neuropathy induced by an anti-neoplasic drug, vincristine. Vincristine-treated rats (0.1mg/kg, daily i.p. administration for two 5-day cycles) developed thermal allodynia and mechanical hypersensitivity, which decreased in a dose-related manner after epidural injection a 5-HT2A receptor antagonist. Moreover, 5-HT2A-/- mice did not develop vincristine-induced neuropathy contrarily to their 5-HT2A+/+ littermates. In vincristine-treated rats, the number of nociceptive dorsal root ganglion cells expressing the 5-HT2AR was increased by 38%, and 5-HT2AR immunolabelling was enhanced in layers I-IV of the dorsal horn. At the EM level, a 76.3% increase in the density of 5-HT2AR immunopositive axon terminals within superficial layers of the dorsal horn was noted after vincristine treatment. Immunocytochemical study of Fos expression in vincristine-treated rats revealed a significant increase in the number of Fos-positive neurons not only in regions where nociceptive fibres terminate superficial (I-II) and deep layers (V-VI) of the spinal cord, but also in intermediate layers, suggesting that Abeta fibres could be involved in the spinal sensitization observed in this model. Double labelling experiments showed that Fos-positive neurons were endowed with 5-HT2AR immunolabelling in the dorsal horn of vincristine-treated rats. These data provide support to the idea that, in vincristine-induced neuropathy, 5-HT2AR are involved in the sensitization of peripheral nociceptors and spinal nociceptive processing.

Role of spinal serotonin 5-HT2A receptor in 2',3'-dideoxycytidine-induced neuropathic pain in the rat and the mouse.

Several lines of evidence suggest that descending serotoninergic facilitatory pathways are involved in neuropathic pain. These pathways may involve 5-HT2A receptors known to play a role in spinal and peripheral sensitization. The implication of this receptor in neuropathy was investigated in a model of peripheral neuropathy induced by 2',3'-dideoxycytidine, a nucleoside analogue with reverse transcriptase inhibitory properties used in HIV/AIDS therapy. Four days after a single 100mg/kg i.v. administration in the tail vein, mitochondrial alterations in nociceptive and non-nociceptive dorsal root ganglion cells were observed at the lumbar level. These alterations were not associated with TUNEL labelling or with modification of the total number of dorsal root ganglion cells. At the same time point, 5-HT2A receptor immunolabelling was increased throughout the dorsal horn (by 49.5% in layer II and 57.8% in layer III). The number of 5-HT2A receptor immunoreactive neurons in the dorsal root ganglion was also increased by 30.7%. Four days after 2',3'-dideoxycytidine administration, rats had developed thermal allodynia as well as mechanical hyperalgesia and allodynia, which dose-dependently decreased after epidural injection of MDL 11,939, a 5-HT2A receptor antagonist. Moreover, 5-HT2A receptor knock-out mice did not develop 2',3'-dideoxycytidine-induced neuropathy whereas their control littermates displayed a neuropathy comparable to that observed in rats. Our data show that 2',3'-dideoxycytidine-induced neuropathy is associated with alterations of nociceptive and non-nociceptive peripheral cells and that the 5-HT2A receptor is involved in the peripheral sensitization of nociceptors as well as in a wide central sensitization of dorsal horn neurons.

Midgut volvulus in an adult patient with malrotation and abdominal heterotaxia: a case report.

Midgut volvulus is rare in adulthood and if not diagnosed accurately, carries a high mortality rate. We present a case of a young adult man who presented with acute abdominal pain and was found to have malrotation with abdominal heterotaxia. Abdominal computed tomography can identify anomalies associated with intestinal malrotation. With the awareness of the potential for malrotation to predispose to midgut volvulus, the patient and his physician will have a higher index of suspicion when abdominal pain occurs. Appropriate treatment of midgut volvulus will reduce morbidity and mortality.

Impact of a residency research program on research activity, faculty involvement, and institutional cost.

BACKGROUND: The impact of residency research programs on resident research activity, faculty involvement, and institutional cost has not been well described. DESCRIPTION: A strategy to increase resident research activity was implemented in a community-based internal medicine residency program. Strategy components included a resident research director, a research elective, cost reimbursement, and a research requirement. Associated outcomes of research activity, faculty involvement, and institutional cost are described. EVALUATION: The annual number of research submissions increased from 0 to 39 over 6 years. The greatest increase in number of research submissions was seen following the dual implementation of the cost reimbursement and research requirement interventions. The annual number of faculty coauthors rose from 0 to 24 in 6 years. Average cost per accepted project was US 1,023.00 dollars. CONCLUSION: The strategy described was associated with a marked increase in resident research activity and faculty involvement. The cost of supporting resident research activity is significant.

Fast computation of the narcissus reflection coefficient for the Herschel far-infrared/submillimeter-wave Cassegrain telescope.

Placement of a scatter cone at the center of the secondary of a Cassegrain telescope greatly reduces Nareissus reflection. To calculate the remaining Narcissus reflection, a time-consuming physical optics code/such as GRASP8 is often used to model the effects of reflection and diffraction. Fortunately, the Cassegrain geometry is sufficiently simple that a combination of theoretical analysis and Fourier propagation can yield rapid, accurate results at submillimeter wavelengths. We compare these results with those from GRASP8 for the heterodyne instrument for the far-infrared on the Herschel Space Observatory and confirm the effectiveness of the chosen scatter cone design.

Cryogenic far-infrared laser absorptivity measurements of the Herschel Space Observatory telescope mirror coatings.

Far-infrared laser calorimetry was used to measure the absorptivity, and thus the emissivity, of aluminum-coated silicon carbide mirror samples produced during the coating qualification run of the Herschel Space Observatory telescope to be launched by the European Space Agency in 2007. The samples were measured at 77 K to simulate the operating temperature of the telescope in its planned orbit about the second Lagrangian point, L2, of the Earth-Sun system. Together, the telescope's equilibrium temperature in space and the emissivity of the mirror surfaces will determine the far-infrared-submillimeter background and thus the sensitivity of two of the three astronomical instruments aboard the observatory if stray-light levels can be kept low relative to the mirror emission. Absorptivities of both clean and dust-contaminated samples were measured at 70, 118, 184, and 496 microm. Theoretical fits to the data predict absorptivities of 0.2-0.4% for the clean sample and 0.2-0.8% for the dusty sample, over the spectral range of the Herschel Space Observatory instruments.