Sensitization of Endothelial Cells to Ionizing Radiation Exacerbates Delayed Radiation Myelopathy in Mice.

Delayed radiation myelopathy is a rare, but significant late side effect from radiation therapy that can lead to paralysis. The cellular and molecular mechanisms leading to delayed radiation myelopathy are not completely understood but may be a consequence of damage to oligodendrocyte progenitor cells and vascular endothelial cells. Here, we aimed to determine the contribution of endothelial cell damage to the development of radiation-induced spinal cord injury using a genetically defined mouse model in which endothelial cells are sensitized to radiation due to loss of the tumor suppressor p53. Tie2Cre; p53FL/+ and Tie2Cre; p53FL/- mice, which lack one and both alleles of p53 in endothelial cells, respectively, were treated with focal irradiation that specifically targeted the lumbosacral region of the spinal cord. The development of hindlimb paralysis was followed for up to 18 weeks after either a 26.7 Gy or 28.4 Gy dose of radiation. During 18 weeks of follow-up, 83% and 100% of Tie2Cre; p53FL/- mice developed hindlimb paralysis after 26.7 and 28.4 Gy, respectively. In contrast, during this period only 8% of Tie2Cre; p53FL/+ mice exhibited paralysis after 28.4 Gy. In addition, 8 weeks after 28.4 Gy the irradiated spinal cord from Tie2Cre; p53FL/- mice showed a significantly higher fractional area positive for the neurological injury marker glial fibrillary acidic protein (GFAP) compared with the irradiated spinal cord from Tie2Cre; p53FL/+ mice. Together, our findings show that deletion of p53 in endothelial cells sensitizes mice to the development of delayed radiation myelopathy indicating that endothelial cells are a critical cellular target of radiation that regulates myelopathy.

Sudden Unexpected Death in a Child From Acute Myeloid Leukemia.

ABSTRACT: Acute myeloid leukemia can rarely cause sudden, unexpected death in children. Presentation may be non-specific and death may occur in children with no prior medical history. Herein we present the case of a previously healthy 2-year and 2 month-old White girl, who on autopsy, was found to have acute myeloid leukemia with KMT2A rearrangement extensively involving all major thoracic and abdominal organs. This case is presented to the forensic community to discuss the presentation and findings in sudden death caused by acute leukemia. The case highlights when acute leukemia should enter the differential as a potential cause of death, as well as potential resources available in the postmortem workup of acute leukemias.

Cyclophosphamide-induced cystitis results in NLRP3-mediated inflammation in the hippocampus and symptoms of depression in rats.

Recent breakthroughs demonstrate that peripheral diseases can trigger inflammation in the brain, causing psychosocial maladies, including depression. While few direct studies have been made, anecdotal reports associate urological disorders with mental dysfunction. Thus, we investigated if insults targeted at the bladder might elicit behavioral alterations. Moreover, the mechanism of neuroinflammation elicited by other peripheral diseases involves the NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome, which is present in microglia in the brain and cleaves and activates proinflammatory cytokines such as IL-1ß. Thus, we further explored the importance of NLRP3 in behavioral and neuroinflammatory changes. Here, we used the well-studied cyclophosphamide (CP)-treated rat model. Importantly, CP and its metabolites do not cross the blood-brain barrier or trigger inflammation in the gut, so that any neuroinflammation is likely secondary to bladder injury. We found that CP triggered an increase in inflammasome activity (caspase-1 activity) in the hippocampus but not in the pons. Evans blue extravasation demonstrated breakdown of the blood-brain barrier in the hippocampal region and activated microglia were present in the fascia dentata. Both changes were dependent on NLRP3 activation and prevented with 2-mercaptoethane sulfonate sodium (Mesna), which masks the effects of the CP metabolite acrolein in the urine. Finally, CP-treated rats displayed depressive symptoms that were prevented by NLRP3 inhibition or treatment with Mesna or an antidepressant. Thus, we conclude that CP-induced cystitis causes NLRP3-dependent hippocampal inflammation leading to depression symptoms in rats. This study proposes the first-ever causative explanation of the previously anecdotal link between benign bladder disorders and mood disorders.

Hemorrhagic Retinopathy and Optic Nerve Sheath Hemorrhage Associated With Fatal Subarachnoid Hemorrhage from a Ruptured Intracranial Aneurysm Due to Segmental Fibromuscular Dysplasia.

Fibromuscular dysplasia is an idiopathic, nonatheromatous, and noninflammatory arterial disease that most commonly affects the renal and carotid arteries. We report a child with subarachnoid and ocular hemorrhage associated with an aneurysm due to fibromuscular dysplasia. Computed tomography following a witnessed collapse revealed diffuse subarachnoid hemorrhage and severe cerebral edema. An autopsy confirmed the radiographic findings and detected bilateral retinal hemorrhages, optic nerve sheath hemorrhages, and a ruptured saccular aneurysm due to focal fibromuscular dysplasia involving the intracranial right vertebral artery. This case documents a fatal subarachnoid hemorrhage in a child with an intracranial saccular aneurysm caused by fibromuscular dysplasia. The associated retinal hemorrhages are easily detected by postmortem monocular indirect ophthalmoscopy.

The Trifluoromethyl Group as a Bioisosteric Replacement of the Aliphatic Nitro Group in CB1 Receptor Positive Allosteric Modulators.

The first generation of CB1 positive allosteric modulators (e.g., ZCZ011) featured a 3-nitroalkyl-2-phenyl-indole structure. Although a small number of drugs include the nitro group, it is generally not regarded as being "drug-like", and this is particularly true for aliphatic nitro groups. There are very few case studies where an appropriate bioisostere replaced a nitro group that had a direct role in binding. This may be indicative of the difficulty of replicating its binding interactions. Herein, we report the design and synthesis of ligands targeting the allosteric binding site on the CB1 cannabinoid receptor, in which a CF3 group successfully replaced the aliphatic NO2. In general, the CF3-bearing compounds were more potent than their NO2 equivalents and also showed improved in vitro metabolic stability. The CF3 analogue (1) with the best balance of properties was selected for further pharmacological evaluation. Pilot in vivo studies showed that (±)-1 has similar activity to (±)-ZCZ011, with both showing promising efficacy in a mouse model of neuropathic pain.

Sudden Unexpected Death in a Child From an Anaplastic Ependymoma.

Primary central nervous system tumors are an extremely rare cause of sudden, unexpected death in children as most patients develop symptoms because of increased intracranial pressure and seek medical attention. Rarely, a forensic pathologist may encounter a primary intracranial neoplasm in a pediatric decedent that was not suspected before death. Herein, we present a case of a supratentorial neuroepithelial tumor found at autopsy in a 3-year-old African American boy without any reported significant medical history. The tumor had significant mass effect and caused cerebral edema, which ultimately resulted in transtentorial herniation and death. The gross, histopathological, immunohistochemical, and ultrastructural findings were most consistent with an anaplastic ependymoma.

Fatal Granulomatous Amebic Encephalitis in a Heart Transplant Patient: Clinical, Radiographic, and Autopsy Findings.

Granulomatous amebic encephalitis is a rare necrotizing infection of the CNS that occurs most commonly in immunocompromised individuals and is usually fatal. It is difficult to diagnose as the clinical symptoms and radiographic findings are often mistaken for other bacterial, viral, fungal, or protozoan infections. Herein, we present the case of a 69-year-old heart transplant recipient who suffered fulminant neurological decline ∼5 months after transplant. Extensive radiographic and laboratory testing did not provide a definite anatomic diagnosis and, despite aggressive clinical treatment, he died. An autopsy examination demonstrated numerous brain abscesses which contained amebic trophozoites and cysts. An indirect immunofluorescence assay performed at the Centers for Disease Control confirmed the presence of Acanthamoeba species. To the best of our knowledge, only 13 other cases of Acanthamoeba amebic encephalitis have been reported in patients who have received solid organ transplants and this is the second case reported in a heart transplant recipient. This case emphasizes that amebic encephalitis should be in the differential diagnosis for immunocompromised patients with new brain lesions found on radiographic imaging.

3-Fluoro-4-hydroxyprolines: Synthesis, Conformational Analysis, and Stereoselective Recognition by the VHL E3 Ubiquitin Ligase for Targeted Protein Degradation.

Hydroxylation and fluorination of proline alters the pyrrolidine ring pucker and the trans:cis amide bond ratio in a stereochemistry-dependent fashion, affecting molecular recognition of proline-containing molecules by biological systems. While hydroxyprolines and fluoroprolines are common motifs in medicinal and biological chemistry, the synthesis and molecular properties of prolines containing both modifications, i.e., fluoro-hydroxyprolines, have not been described. Here we present a practical and facile synthesis of all four diastereoisomers of 3-fluoro-4-hydroxyprolines (F-Hyps), starting from readily available 4-oxo-l-proline derivatives. Small-molecule X-ray crystallography, NMR spectroscopy, and quantum mechanical calculations are consistent with fluorination at C3 having negligible effects on the hydrogen bond donor capacity of the C4 hydroxyl, but inverting the natural preference of Hyp from C4-exo to C4-endo pucker. In spite of this, F-Hyps still bind to the von Hippel-Lindau (VHL) E3 ligase, which naturally recognizes C4-exo Hyp in a stereoselective fashion. Co-crystal structures and electrostatic potential calculations support and rationalize the observed preferential recognition for (3 R,4 S)-F-Hyp over the corresponding (3 S,4 S) epimer by VHL. We show that (3 R,4 S)-F-Hyp provides bioisosteric Hyp substitution in both hypoxia-inducible factor 1 alpha (HIF-1α) substrate peptides and peptidomimetic ligands that form part of PROTAC (proteolysis targeting chimera) conjugates for targeted protein degradation. Despite a weakened affinity, Hyp substitution with (3 S,4 S)-F-Hyp within the PROTAC MZ1 led to Brd4-selective cellular degradation at concentrations >100-fold lower than the binary Kd for VHL. We anticipate that the disclosed chemistry of 3-fluoro-4-hydroxyprolines and their application as VHL ligands for targeted protein degradation will be of wide interest to medicinal organic chemists, chemical biologists, and drug discoverers alike.

Recurrent Glioblastoma Treated with Recombinant Poliovirus.

BACKGROUND: The prognosis of patients with recurrent World Health Organization (WHO) grade IV malignant glioma is dismal, and there is currently no effective therapy. We conducted a dose-finding and toxicity study in this population of patients, evaluating convection-enhanced, intratumoral delivery of the recombinant nonpathogenic polio-rhinovirus chimera (PVSRIPO). PVSRIPO recognizes the poliovirus receptor CD155, which is widely expressed in neoplastic cells of solid tumors and in major components of the tumor microenvironment. METHODS: We enrolled consecutive adult patients who had recurrent supratentorial WHO grade IV malignant glioma, confirmed on histopathological testing, with measurable disease (contrast-enhancing tumor of ≥1 cm and ≤5.5 cm in the greatest dimension). The study evaluated seven doses, ranging between 107 and 1010 50% tissue-culture infectious doses (TCID50), first in a dose-escalation phase and then in a dose-expansion phase. RESULTS: From May 2012 through May 2017, a total of 61 patients were enrolled and received a dose of PVSRIPO. Dose level -1 (5.0×107 TCID50) was identified as the phase 2 dose. One dose-limiting toxic effect was observed; a patient in whom dose level 5 (1010 TCID50) was administered had a grade 4 intracranial hemorrhage immediately after the catheter was removed. To mitigate locoregional inflammation of the infused tumor with prolonged glucocorticoid use, dose level 5 was deescalated to reach the phase 2 dose. In the dose-expansion phase, 19% of the patients had a PVSRIPO-related adverse event of grade 3 or higher. Overall survival among the patients who received PVSRIPO reached a plateau of 21% (95% confidence interval, 11 to 33) at 24 months that was sustained at 36 months. CONCLUSIONS: Intratumoral infusion of PVSRIPO in patients with recurrent WHO grade IV malignant glioma confirmed the absence of neurovirulent potential. The survival rate among patients who received PVSRIPO immunotherapy was higher at 24 and 36 months than the rate among historical controls. (Funded by the Brain Tumor Research Charity and others; ClinicalTrials.gov number, NCT01491893 .).

Expected and unexpected products of reactions of 2-hydrazinylbenzo-thia-zole with 3-nitro-benzene-sulfonyl chloride in different solvents.

The syntheses and crystal structures of 2-[2-(propan-2-yl-idene)hydrazin-yl]-1,3-benzo-thia-zol-3-ium 3-nitro-benzene-sulfonate (C10H12N2S+·C6H4NO5S-), (I), 2-[2-(3-nitro-benzene-sulfon-yl)hydrazin-yl]-1,3-benzo-thia-zole (C13H10N4O4S2), (II) and 2-[2-(3-nitro-benzene-sulfon-yl)hydrazin-yl]-1,3-benzo-thia-zol-3-ium 3-nitro-benzene-sulfonate (C13H11N4O4S2+·C6H4NO5S-), (III) are reported. Salt (I) arose from an unexpected reaction of 2-hydrazinylbenzo-thia-zole with the acetone solvent in the presence of 3-nitro-benzene-sulfonyl chloride, whereas (II) and (III) were recovered from the equivalent reaction carried out in methanol. The crystal of (I) features ion pairs linked by pairs of N-H⋯Os (s = sulfonate) hydrogen bonds; adjacent cations inter-act by way of short π-π stacking inter-actions between the thia-zole rings [centroid-centroid separation = 3.4274 (18) Å]. In (II), which crystallizes with two neutral mol-ecules in the asymmetric unit, the mol-ecules are linked by N-H⋯N and N-H⋯On (n = nitro) hydrogen bonds to generate [[Formula: see text]1[Formula: see text]] chains, which are cross-linked by C-H⋯O and π-π stacking inter-actions. The crystal of (III) features centrosymmetric tetra-mers (two cations and two anions) linked by cooperative N-H⋯O hydrogen bonds; C-H⋯O and π-π inter-actions occur between tetra-mers.

Cerebral Toxoplasmosis: A Case Report with Correlation of Radiographic Imaging, Surgical Pathology, and Autopsy Findings.

Cerebral toxoplasmosis is an opportunistic infection of the central nervous system. Certain radiographic findings can be highly suggestive of the disease, but there is considerable overlap with both lymphoma and brain metastases, making the diagnosis difficult or delayed. Herein we present the case of a 77-year-old woman with a history of treated diffuse large B-cell lymphoma who presented with neurological symptoms four months after she was declared to be in remission. Her initial head computed tomography scan showed multiple low-attenuated lesions in her brain and a contrast enhanced magnetic resonance imaging scan showed multiple T1- and T2- enhancing lesions in the basal ganglia and at the gray-white junction. The clinical team was highly suspicious of a recurrence of her lymphoma so she had an extensive workup, including a brain biopsy, which did not lead to a definite diagnosis. After she died, an autopsy was performed, and multiple necrotic lesions were discovered in her brain. Histologic sections demonstrated numerous parasitic organisms, and immunohistochemical staining for Toxoplasma gondii was positive, confirming the diagnosis of cerebral toxoplasmosis. This case highlights an unusual case of cerebral toxoplasmosis that was diagnosed at autopsy and reviews the relevant radiographic findings as well as the gross and microscopic pathological features of the disease.

Crystal structures of [Mn(bdc)(Hspar)2(H2O)0.25]·2H2O containing MnO6+1 capped trigonal prisms and [Cu(Hspar)2](bdc)·2H2O containing CuO4 squares (Hspar = sparfloxacin and bdc = benzene-1,4-di-carboxyl-ate).

The syntheses and crystal structures of 0.25-aqua-(benzene-1,4-di-carboxyl-ato-κ(2) O,O')bis-(sparfloxacin-κ(2) O,O')manganese(II) dihydrate, [Mn(C8H4O4)(C19H22F2N4O3)2(H2O)0.25]·2H2O or [Mn(bdc)(Hspar)2(H2O)0.25]·2H2O, (I), and bis-(sparfloxacin-κ(2) O,O')copper(II) benzene-1,4-di-carboxyl-ate dihydrate, [Cu(C19H22F2N4O3)2](C8H4O4)·2H2O or [Cu(Hspar)2](bdc)·2H2O, (II), are reported (Hspar = sparfloxacin and bdc = benzene-1,4-di-carboxyl-ate). The Mn(2+) ion in (I) is coordinated by two O,O'-bidentate Hspar neutral mol-ecules (which exist as zwitterions) and an O,O'-bidentate bdc dianion to generate a distorted MnO6 trigonal prism. A very long bond [2.580 (12) Å] from the Mn(2+) ion to a 0.25-occupied water mol-ecule projects through a square face of the prism. In (II), the Cu(2+) ion lies on a crystallographic inversion centre and a CuO4 square-planar geometry arises from its coordination by two O,O'-bidentate Hspar mol-ecules. The bdc dianion acts as a counter-ion to the cationic complex and does not bond to the metal ion. The Hspar ligands in both (I) and (II) feature intra-molecular N-H⋯O hydrogen bonds, which close S(6) rings. In the crystals of both (I) and (II), the components are linked by N-H⋯O, O-H⋯O and C-H⋯O hydrogen bonds, generating three-dimensional networks.

New palladium(II) and platinum(II) 5,5-diethylbarbiturate complexes with 2-phenylpyridine, 2,2'-bipyridine and 2,2'-dipyridylamine: synthesis, structures, DNA binding, molecular docking, cellular uptake, antioxidant activity and cytotoxicity.

Novel palladium(ii) and platinum(ii) complexes of 5,5-diethylbarbiturate (barb) with 2-phenylpyridine (Hppy), 2,2'-bipyridine (bpy) and 2,2'-dipyridylamine (dpya) have been prepared and characterized by elemental analysis, IR, UV-Vis, NMR and ESI-MS. Single-crystal diffraction measurements show that complex consists of binuclear [Pd2(µ-barb-κN,O)2(ppy-κN,C)2] moieties, while complexes are mononuclear, [M(barb-κN)2(L-κN,N')] (L = bpy or dpya). has a composition of [Pt(dpya-κN,N')2][Ag(barb-κN)2]2·4H2O and was assumed to have a structure of [Pt(barb-κN)(Hppy-κN)(ppy-κN,C)]·3H2O. The complexes were found to exhibit significant DNA binding affinity by a non-covalent binding mode, in accordance with molecular docking studies. In addition, complexes and displayed strong binding with supercoiled pUC19 plasmid DNA. Cellular uptake studies were performed to assess the subcellular localization of the selected complexes. A moderate radical scavenging activity of and was confirmed by DPPH and ABTS tests. Complexes , , and showed selectivity against HT-29 (colon) cell line.

trans-Dichloridopalladium(II) and platinum(II) complexes with 2-(hydroxymethyl)pyridine and 2-(2-hydroxyethyl)pyridine: synthesis, structural characterization, DNA binding and in vitro cytotoxicity studies.

Four trans-palladium(II)- and trans-platinum(II)-chlorido complexes, trans-[PdCl(2)(2-hmpy)(2)] (1), trans-[PtCl(2)(2-hmpy)(2)] (2), trans-[PdCl(2)(2-hepy)(2)] (3) and trans-[PtCl(2)(2-hepy)(2)] (4) (2-hmpy = 2-(hydroxymethyl)pyridine and 2-hepy = 2-(2-hydroxyethyl)pyridine), have been synthesized and characterized by elemental analysis, IR, NMR, and X-ray diffraction. The binding properties of these complexes with fish sperm DNA (FS-DNA) were investigated by UV titration, viscosity, thermal denaturation and electrophoresis measurements. The complexes can bind to FS-DNA and complex 4 exhibits the highest binding constant. Gel electrophoresis assay demonstrates that all the complexes can cleave the pCMV-ßgal plasmid DNA to a different degree. The cytotoxic activities of the complexes were tested against four different cancer cell lines. In general, the platinum(II) complexes are more effective than the isostructural palladium(II) complexes. Complex 4 shows high anticancer activity, compared to transplatin, cisplatin, carboplatin and oxaliplatin.

N-(2,3-Dimethyl-phen-yl)-4-fluoro-N-[(4-fluoro-phen-yl)sulfon-yl]benzene-sulfonamide.

In the title compound, C(20)H(17)F(2)NO(4)S(2), the dihedral angles between the o-xylene ring and the fluoro-benzene rings are 31.7 (1) and 32.8 (1)°, and the dihedral angle between the fluoro-benzene rings is 50.9 (1)°. The C-N-S-C torsion angles are 76.7 (2) and 101.8 (2)°. In the crystal, mol-ecules are connected by C-H⋯O inter-actions into sheets in the ab plane.

N-(2,3-Dimethyl-phen-yl)-4-methyl-N-(4-methyl-phenyl-sulfon-yl)benzene-sulfonamide.

In the title compound, C(22)H(23)NO(4)S(2), the dihedral angles between the dimethyl-phenyl ring and the two methyl-phenyl rings are 41.19 (15) and 20.50 (17)°; the dihedral angle between the methyl-phenyl rings is 48.11 (14)°. The C-N-S-C torsion angles are -87.6 (2) and 77.43 (18)°. The only possible directional inter-actions in the crystal are very weak C-H⋯π inter-actions and very weak π-π stacking between parallel methyl-phenyl rings [centroid-to-centroid separation = 4.010 (2) Šand slippage = 1.987 Å].

2,5-Dichloro-N-(2,3-dimethyl-phen-yl)benzene-sulfonamide.

In the title compound, C(14)H(13)Cl(2)NO(2)S, the dihedral angle between the aromatic rings is 62.21 (7)° and the C-S-N-C group adopts a gauche conformation [torsion angle = 60.22 (17)°]. In the crystal, N-H⋯O hydrogen bonds link the mol-ecules into C(4) chains propagating in [010]. A short inter-molecular Cl⋯O contact of 3.1115 (17) Šis seen.