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1.
Brain Commun ; 5(2): fcad030, 2023.
Article in English | MEDLINE | ID: mdl-36895955

ABSTRACT

Spastic paraparesis has been described to occur in 13.7% of PSEN1 mutations and can be the presenting feature in 7.5%. In this paper, we describe a family with a particularly young onset of spastic paraparesis due to a novel mutation in PSEN1 (F388S). Three affected brothers underwent comprehensive imaging protocols, two underwent ophthalmological evaluations and one underwent neuropathological examination after his death at age 29. Age of onset was consistently at age 23 with spastic paraparesis, dysarthria and bradyphrenia. Pseudobulbar affect followed with progressive gait problems leading to loss of ambulation in the late 20s. Cerebrospinal fluid levels of amyloid-ß, tau and phosphorylated tau and florbetaben PET were consistent with Alzheimer's disease. Flortaucipir PET showed an uptake pattern atypical for Alzheimer's disease, with disproportionate signal in posterior brain areas. Diffusion tensor imaging showed decreased mean diffusivity in widespread areas of white matter but particularly in areas underlying the peri-Rolandic cortex and in the corticospinal tracts. These changes were more severe than those found in carriers of another PSEN1 mutation, which can cause spastic paraparesis at a later age (A431E), which were in turn more severe than among persons carrying autosomal dominant Alzheimer's disease mutations not causing spastic paraparesis. Neuropathological examination confirmed the presence of cotton wool plaques previously described in association with spastic parapresis and pallor and microgliosis in the corticospinal tract with severe amyloid-ß pathology in motor cortex but without unequivocal disproportionate neuronal loss or tau pathology. In vitro modelling of the effects of the mutation demonstrated increased production of longer length amyloid-ß peptides relative to shorter that predicted the young age of onset. In this paper, we provide imaging and neuropathological characterization of an extreme form of spastic paraparesis occurring in association with autosomal dominant Alzheimer's disease, demonstrating robust diffusion and pathological abnormalities in white matter. That the amyloid-ß profiles produced predicted the young age of onset suggests an amyloid-driven aetiology though the link between this and the white matter pathology remains undefined.

2.
Cardiovasc Pathol ; 50: 107289, 2021.
Article in English | MEDLINE | ID: mdl-32949727

ABSTRACT

Alveolar capillary dysplasia with misalignment of pulmonary veins (ACD/MPV) is a rare neonatal lung disease with fatal outcome. Typically, respiratory symptoms present in the first 24 hours of life and patients die within the neonatal period. Atypical, delayed clinical presentations and/or longer survival have also been reported. Here, we studied the clinicopathologic relationship of ACD/MPV by examining 16 cases of ACD/MPV, focusing on atypical features. Based on the presence of diffuse vs. focal/patchy ACD/MPV histopathologic changes, we divided the cases into classic and nonclassic pathology groups. MPV was found in all ACD/MPV. Ten of 16 cases exhibited classic diffuse abnormalities, while 6 of 16 had a nonclassic focal/patchy distribution. However, among 7 patients with atypical clinical features, only 2 had nonclassic pathology, while 4 out of 9 clinically typical cases had nonclassic ACD/MPV pathology. Marked intrapulmonary aberrant arteriovenous vessels were present in all atypical cases. In conclusion, clinical presentation is not always correlated with histopathology in ACD/MPV. Atypical ACD/MPV should be suspected in any infants with fulminant pulmonary hypertension. Abnormal pulmonary veins and aberrant intraseptal vessels are the most important clues for diagnosis. Additional studies are needed for further elucidation of diagnostic histological criteria of atypical ACD/MPV and to explore its pathogenesis.


Subject(s)
Persistent Fetal Circulation Syndrome/pathology , Pulmonary Alveoli/abnormalities , Pulmonary Veins/abnormalities , Autopsy , Female , Gestational Age , Humans , Male , Persistent Fetal Circulation Syndrome/mortality , Prognosis , Pulmonary Alveoli/pathology , Retrospective Studies
3.
MethodsX ; 6: 718-726, 2019.
Article in English | MEDLINE | ID: mdl-31011543

ABSTRACT

Invadopodia, cancer cell protrusive structures with associated proteolytic activity, provide cancer cells with the ability to remodel the extracellular matrix. Invadopodia facilitate invasive migration and their formation correlates with cancer cell invasiveness and metastatic potential. The unambiguous identification of invadopodia is an important step to undergo studies on invadopodia regulatory inputs, functional outputs, as well as the prevalence and significance of invadopodia for cancer cells and human tumors. The adaptor protein TKS5 is a known invadopodia regulatory protein, which is necessary for invadopodia formation and activity. TKS5 is highly enriched at invadopodia and, unlike other commonly used invadopodia markers, it does not accumulate significantly in other types of cellular protrusions. However, the use of TKS5 as a marker of invadopodia has not been generalized, in part due to the availability of suitable antibodies against the human protein. We have evaluated two commercial antibodies raised against human TKS5. Here, we detail protocols for the detection of invadopodia-associated TKS5 in human cells in culture and in paraffin-embedded archived tumor surgical specimens using commercial antibodies. These methods should facilitate the identification and study of human invadopodia. •TKS5 staining identifies invadopodia in human cancer cell lines and archived surgical tumor specimens.

4.
Exp Mol Pathol ; 106: 17-26, 2019 02.
Article in English | MEDLINE | ID: mdl-30439350

ABSTRACT

Invadopodia, cancer cell protrusions with proteolytic activity, are functionally associated with active remodeling of the extracellular matrix. Here, we show that the invadopodia-related protein TKS5 is expressed in human pancreatic adenocarcinoma lines, and demonstrate that pancreatic cancer cells depend on TKS5 for invadopodia formation and function. Immunofluorescence staining of human pancreatic cancer cells reveals that TKS5 is a marker of mature and immature invadopodia. We also analyze the co-staining patterns of TKS5 and the commonly used invadopodia marker Cortactin, and find only partial co-localization of these two proteins at invadopodia, with a large fraction of TKS5-positive invadopodia lacking detectable levels of Cortactin. Whereas compelling evidence exist on the role of invadopodia as mediators of invasive migration in cultured cells and in animal models of cancer, these structures have never been detected inside human tumors. Here, using antibodies against TKS5 and Cortactin, we describe for the first time structures strongly resembling invadopodia in various paraffin-embedded human tumor surgical specimens from pancreas and other organs. Our results strongly suggest that invadopodia are present inside human tumors, and warrants further investigation on their regulation and occurrence in surgical specimens, and on the value of TKS5 antibodies as pathological research and diagnostic tools.


Subject(s)
Adaptor Proteins, Vesicular Transport/physiology , Adenocarcinoma/pathology , Neoplasm Proteins/physiology , Pancreatic Neoplasms/pathology , Podosomes/physiology , Adenocarcinoma/chemistry , Adenocarcinoma/surgery , Adenocarcinoma/ultrastructure , Adult , Aged , Cell Line, Tumor , Cortactin/analysis , Female , Fluorescent Antibody Technique, Direct , Humans , Male , Middle Aged , Neoplasm Invasiveness , Neoplasms/chemistry , Neoplasms/pathology , Pancreatic Neoplasms/chemistry , Pancreatic Neoplasms/surgery , Pancreatic Neoplasms/ultrastructure , Paraffin Embedding , Podosomes/chemistry , Podosomes/ultrastructure , RNA Interference , RNA, Small Interfering/genetics
5.
Data Brief ; 22: 132-136, 2019 Feb.
Article in English | MEDLINE | ID: mdl-30581916

ABSTRACT

In this article, using human pancreatic cancer cell lines and tumor specimens, we analyze the expression and localization of the invadopodia-related proteins TKS5 and Cortactin. Specifically, we present data on: a) TKS5 expression and localization by immunofluorescence in human pancreatic tumors, b) Cortactin expression by western blotting in various human pancreatic adenocarcinoma cell lines, c) TKS5 and Cortactin localization at invadopodia in BxPC-3 pancreatic adenocarcinoma cells, and d) TKS5 and Cortactin localization by co-immunofluorescence in human pancreatic cancer specimens. Data presented here is related to and supportive of the research article by Chen et al., "TKS5-positive invadopodia-like structures in human tumor surgical specimens" (Chen et al., 2019), where interpretation of the research data presented here is available.

7.
Exp Mol Pathol ; 104(2): 151-154, 2018 04.
Article in English | MEDLINE | ID: mdl-29551574

ABSTRACT

Amyloidosis is a disorder characterized by the deposition of insoluble abnormal proteins in the extracellular space. It may occur as a localized lesion or as a systemic disease involving multiple organs and systems. Localized conjunctival amyloidosis is rare and is less frequently associated with systemic involvement. Although amyloidosis itself is a benign lesion involvement of multiple organs and systems is associated with poor prognosis. Diagnosis of amyloidosis is made on biopsy specimens with Congo red staining for the appearance of apple-green birefringence under polarized light microscopy. Liquid chromatography tandem-mass spectrometry (LC-MS/MS) is much more sensitive in diagnosing amyloidosis and can determine the type of amyloid deposit. Here we reported a case of conjunctival amyloidosis in a 52 year-old male patient who was presented with left lower eyelid swelling to our medical center. He has a complicated past medical history of anti-phospholipid antibody syndrome, Buerger's disease (thromboangitis obliterans), and small cell lymphoma (SLL) of the right orbit/eyelid. The patient received radiation to the right orbit to treat SLL with therapy completed one and a half years prior to presentation. Physical examination revealed a firm, raised yellowish colored lesion in the left lower conjunctiva. The conjunctival lesion was biopsied, and tissue sections were examined with Congo red stains and LC-MS/MS analysis. The biopsy showed amyloid deposits without evidence of malignancy, and the type of proteins in the deposit was immunoglobulin light chain (AL) of kappa type. A complete work up was taken for possible systemic involvement of amyloidosis and results were all negative. To our knowledge, this is the first case of localized conjunctival amyloidosis with a history of contralateral orbit/eyelid SLL.


Subject(s)
Amyloidosis/pathology , Conjunctival Diseases/pathology , Lymphoma/pathology , Orbital Neoplasms/pathology , Antiphospholipid Syndrome/etiology , Biopsy , Humans , Lymphoma/radiotherapy , Lymphoma, Non-Hodgkin/radiotherapy , Male , Middle Aged , Orbit/pathology , Orbital Neoplasms/radiotherapy , Thromboangiitis Obliterans/etiology
8.
Exp Mol Pathol ; 104(2): 158-160, 2018 04.
Article in English | MEDLINE | ID: mdl-29452079

ABSTRACT

A 52 year-old obese male presented with a moderately differentiated adenocarcinoma of the sigmoid colon. On staging CT, the patient was found to have a cystic lesion in the left retroperitoneum.


Subject(s)
Adenocarcinoma/pathology , Bronchogenic Cyst/pathology , Colonic Neoplasms/pathology , Adenocarcinoma/diagnostic imaging , Adenocarcinoma/surgery , Colon, Sigmoid/pathology , Colon, Sigmoid/surgery , Colonic Neoplasms/diagnostic imaging , Colonic Neoplasms/surgery , Humans , Male , Middle Aged , Retroperitoneal Space/pathology , Tomography, X-Ray Computed
9.
Exp Mol Pathol ; 104(2): 155-157, 2018 04.
Article in English | MEDLINE | ID: mdl-29452080

ABSTRACT

A 40 year old female with no documented medical history presented to the Emergency Department with several days of lethargy and altered mental status. She was found to be anemic, thrombocytopenic, and hypotensive. The patient was found to be in severe metabolic acidosis, became bradycardic, and quickly deteriorated. Clinicians suspected thrombotic thrombocytopenic purpura, and the diagnosis was supported by ADAMTS13 testing. The clinicians attempted to place a Quinton catheter for emergent plasmapheresis, but the patient expired before definitive treatment could be initiated. Autopsy was obtained and revealed a right middle lobe consolidation grossly consistent with lymphoid tissue or tumor.


Subject(s)
Lung Neoplasms/pathology , Lymphoma, B-Cell, Marginal Zone/pathology , ADAMTS13 Protein/blood , Adult , Autopsy , Female , Humans , Purpura, Thrombotic Thrombocytopenic/diagnosis
10.
Exp Mol Pathol ; 103(2): 178-180, 2017 10.
Article in English | MEDLINE | ID: mdl-28935394

ABSTRACT

A 34-year old male with a giant condyloma acuminatum of the anus secondary to HIV infection presented to the emergency department with a persistent nose bleed lasting 2-3days, acute anemia, thrombocytopenia, and coagulopathy. The patient also had significant hepatosplenomegaly and elevated liver enzymes which were a new finding since the patient's last hospitalization 1-2month prior to the current admission. A bone marrow biopsy showed diffuse infiltration by carcinoma with neuroendocrine features. The patient quickly developed multi-organ injury, decompensated, and died. An autopsy was obtained which established the diagnosis of small cell carcinoma of the liver.


Subject(s)
Blood Coagulation Disorders/pathology , Bone Marrow Neoplasms/secondary , HIV Infections/complications , Liver Failure/pathology , Pancytopenia/pathology , Small Cell Lung Carcinoma/pathology , Splenic Neoplasms/secondary , Adult , Autopsy , Blood Coagulation Disorders/etiology , Bone Marrow Neoplasms/etiology , Fatal Outcome , HIV Infections/virology , HIV-1/pathogenicity , Humans , Liver Failure/etiology , Lung Neoplasms/etiology , Lung Neoplasms/pathology , Male , Pancytopenia/etiology , Small Cell Lung Carcinoma/etiology , Splenic Neoplasms/etiology
12.
Exp Mol Pathol ; 103(1): 84-86, 2017 08.
Article in English | MEDLINE | ID: mdl-28716574

ABSTRACT

Foregut duplication cysts are extremely rare congenital malformations. Herein we report a case of 73 year old male with a left upper quadrant abdominal lesion identified on CT scan.


Subject(s)
Cysts/diagnostic imaging , Epithelium/diagnostic imaging , Stomach/diagnostic imaging , Aged , Humans , Male , Specimen Handling , Stomach/abnormalities , Tomography, X-Ray Computed
13.
J Exp Med ; 213(2): 167-76, 2016 Feb 08.
Article in English | MEDLINE | ID: mdl-26755705

ABSTRACT

T cell immunoglobulin and ITIM domain (TIGIT) and CD226 emerge as a novel T cell cosignaling pathway in which CD226 and TIGIT serve as costimulatory and coinhibitory receptors, respectively, for the ligands CD155 and CD112. In this study, we describe CD112R, a member of poliovirus receptor-like proteins, as a new coinhibitory receptor for human T cells. CD112R is preferentially expressed on T cells and inhibits T cell receptor-mediated signals. We further identify that CD112, widely expressed on antigen-presenting cells and tumor cells, is the ligand for CD112R with high affinity. CD112R competes with CD226 to bind to CD112. Disrupting the CD112R-CD112 interaction enhances human T cell response. Our experiments identify CD112R as a novel checkpoint for human T cells via interaction with CD112.


Subject(s)
Cell Adhesion Molecules/immunology , Interleukin-2 Receptor beta Subunit/metabolism , Receptors, Cell Surface/immunology , T-Lymphocytes/immunology , Amino Acid Sequence , Animals , Antigens, Differentiation, T-Lymphocyte/metabolism , Cell Adhesion Molecules/genetics , Cell Adhesion Molecules/metabolism , Cell Cycle Checkpoints/immunology , Cell Line, Tumor , Dendritic Cells/immunology , HEK293 Cells , Humans , Ligands , Lymphocyte Activation , Mice , Models, Molecular , Molecular Sequence Data , Nectins , Phylogeny , Receptors, Antigen, T-Cell/metabolism , Receptors, Cell Surface/genetics , Receptors, Cell Surface/metabolism , Receptors, Virus/genetics , Receptors, Virus/immunology , Receptors, Virus/metabolism , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/immunology , Recombinant Fusion Proteins/metabolism , Sequence Homology, Amino Acid , Signal Transduction , T-Lymphocytes/cytology
14.
J Trauma Acute Care Surg ; 79(5): 865-9, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26496114

ABSTRACT

BACKGROUND: The objective of this study was to review the efficacy of intracranial packing as a means of tamponade for life-threatening intraoperative hemorrhage that was refractory to more common techniques for achieving hemostasis. METHODS: Neuroimaging and hospital records were reviewed for the seven adult patients who had experienced life-threateningly severe hemorrhage during intracranial surgery and in whom packing was used to control the bleeding. All packing was left in place at the time of closure and was removed when the patient's condition was considered safe for a second operation. RESULTS: Hemorrhage was successfully halted in all seven patients, and all survived their operations. Six were discharged from the hospital, but one patient with severe parenchymal injury from trauma and multiple medical comorbidities died on postoperative Day 2 after supportive care was withdrawn. Four had an improved Glasgow Outcome Scale (GOS) score at the time of last follow-up, and two of these improved from dependent to independent living. There were no postoperative intracranial or wound infections. CONCLUSION: Intracranial packing to tamponade severe intracranial hemorrhage can be a lifesaving neurosurgical maneuver. LEVEL OF EVIDENCE: Therapeutic study, level V.


Subject(s)
Brain Injuries/complications , Endotamponade/methods , Hospital Mortality/trends , Intracranial Hemorrhages/surgery , Intraoperative Complications/therapy , Neurosurgical Procedures/adverse effects , Adolescent , Adult , Brain Injuries/diagnosis , Endotamponade/mortality , Female , Glasgow Coma Scale , Humans , Intracranial Hemorrhages/etiology , Intracranial Hemorrhages/mortality , Intracranial Hemorrhages/physiopathology , Intraoperative Complications/diagnosis , Intraoperative Complications/mortality , Male , Middle Aged , Neurosurgical Procedures/methods , Risk Assessment , Sampling Studies , Severity of Illness Index , Survival Rate , Treatment Outcome , Young Adult
15.
Pediatr Neurosurg ; 50(2): 63-7, 2015.
Article in English | MEDLINE | ID: mdl-25824532

ABSTRACT

The medical records of all children in whom packing was used to control severe intracranial hemorrhage were reviewed. Eight children, with ages ranging from newborn to 4 years, met the inclusion criteria and all survived. Five were victims of severe closed head trauma, 2 had received penetrating cranial injuries, and 1 developed severe bleeding while undergoing surgery for a malignant tumor in the posterior fossa. Blood loss at the time of removal of the packing was minimal in 7 patients and was surgically controllable in the other. Packing is a simple, efficient, and safe maneuver which can very often halt intracranial bleeding that is considered to be otherwise uncontrollable, and can thereby limit the consequences of prolonged or repeated periods of hypotension and possible exsanguination.


Subject(s)
Endotamponade/methods , Intracranial Hemorrhages/surgery , Intraoperative Complications/surgery , Brain Neoplasms/complications , Brain Neoplasms/surgery , Child, Preschool , Endotamponade/adverse effects , Head Injuries, Closed/complications , Head Injuries, Closed/surgery , Head Injuries, Penetrating/complications , Head Injuries, Penetrating/surgery , Humans , Infant , Infant, Newborn , Intracranial Hemorrhages/etiology , Intraoperative Complications/etiology , Treatment Outcome
16.
Ann Surg Oncol ; 22 Suppl 3: S1574-9, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25519928

ABSTRACT

BACKGROUND: This study investigated how the B7-H5 protein, a new member of the B7 family, is expressed in normal human pancreas tissues and examined its expression changes in pancreatic cancer. METHODS: In this analysis, B7-H5 expression was examined by immunohistochemical staining of frozen specimens from patients undergoing pancreatic resection. RESULTS: Membranous B7-H5 protein was expressed on normal ductal epithelium within the pancreas. Other cell types from the normal pancreas, such as acinar cells and islet cells, did not express B7-H5. In adenocarcinoma, B7-H5 staining was decreased or absent. Interestingly, B7-H5 expression in intraductal papillary mucinous neoplasms varied with grade. No B7-H5 expression was found with other cancer types such as neuroendocrine tumors, but normal ducts adjacent to tumors were highly positive. CONCLUSIONS: The findings showed that B7-H5 expression was restricted to ductal cells in the normal pancreas and the expression was downregulated in pancreatic adenocarcinomas. In addition, the findings showed that B7-H5 expression changes within different stages of dysplasia. The study suggests that loss of the B7-H5 signal may contribute to immune evasion of pancreatic adenocarcinoma. However future studies are needed.


Subject(s)
Adenocarcinoma/metabolism , Biomarkers, Tumor/metabolism , Carcinoma, Pancreatic Ductal/metabolism , Immunoglobulins/metabolism , Pancreas/metabolism , Pancreatic Neoplasms/metabolism , Adenocarcinoma/pathology , Carcinoma, Pancreatic Ductal/pathology , Flow Cytometry , Gene Expression Regulation, Neoplastic , Humans , Immunoenzyme Techniques , Neoplasm Staging , Pancreas/pathology , Pancreatic Neoplasms/pathology , Prognosis , Tumor Cells, Cultured
17.
Medicine (Baltimore) ; 93(27): e198, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25501072

ABSTRACT

5-Fluorouracile, oxaliplatin, irinotecan, and leucovorin (FOLFIRINOX) has not been extensively used in the neoadjuvant setting because of concerns with safety and toxicity. We evaluated our institutional experience with neoadjuvant FOLFIRINOX in borderline resectable pancreatic adenocarcinoma (BRPAC). The primary endpoints were completion of therapy to surgery and negative resection margin (R0) rate. Patients with BRPAC treated with neoadjuvant FOLFIRINOX were retrospectively analyzed. Between August 2011 and September 2013, 20 patients with BRPAC treated with neoadjuvant FOLFIRINOX were identified. Most patients (88.8%) completed FOLFIRINOX therapy and underwent resection. Abutment of venous structures was identified in 13 cases (72.2%), while short segment portal vein encasement in 3 cases (16.6%) with concomitant arterial involvement in 3 cases (16.6%). Isolated superior mesenteric artery abutment was identified in 2 cases (11.2%). Patients received a median of 4 cycles of FOLFIRINOX. There was 1 case of progression. Vascular resection was performed in 9 cases (52.9%). Preoperative radiation therapy was used in 8 patients (44%). All patients underwent margin negative resection (R0). Histopathologic treatment response was evident in 10 cases (58.8%). Neoadjuvant FOLFIRINOX was generally safe and the expected toxicity did not prevent surgery allowing for a high rate of R0 resection.


Subject(s)
Adenocarcinoma/drug therapy , Leucovorin/therapeutic use , Pancreatic Neoplasms/drug therapy , Vitamin B Complex/therapeutic use , Adenocarcinoma/surgery , Aged , Female , Humans , Male , Middle Aged , Neoadjuvant Therapy , Pancreatic Neoplasms/surgery , Retrospective Studies , Treatment Outcome
18.
PLoS One ; 8(10): e76895, 2013.
Article in English | MEDLINE | ID: mdl-24204697

ABSTRACT

G-protein-coupled receptors (GPCR) are the largest family of cell surface molecules that play important role/s in a number of biological and pathological processes including cancers. Earlier studies have highlighted the importance of Wnt7a signaling via its cognate receptor Frizzled9, a GPCR, in inhibition of cell proliferation, anchorage-independent growth, and reversal of transformed phenotype in non small cell lung cancer primarily through activation of the tumor suppressor, PPARγ. However, the G-protein effectors that couple to this important tumor suppressor pathway have not been identified, and are of potential therapeutic interest. In this study, by using two independent Wnt7a/Frizzled9-specific read-outs, we identify Gα16 as a novel downstream effector of Wnt7a/Frizzled9 signaling. Interestingly, Gα16 expression is severely down-regulated, both at the messenger RNA levels and protein levels, in many non small cell lung cancer cell lines. Additionally, through gene-specific knock-downs and expression of GTPase-deficient forms (Q212L) of Gα16, we also establish Gα16 as a novel regulator of non small cell lung cancer cell proliferation and anchorage-independent cell growth. Taken together, our data not only establish the importance of Gα16 as a critical downstream effector of the non-canonical Wnt signaling pathway but also as a potential therapeutic target for the treatment of non small cell lung cancer.


Subject(s)
Cell Proliferation , GTP-Binding Protein alpha Subunits, Gq-G11/metabolism , Growth Inhibitors/metabolism , Wnt Signaling Pathway , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/metabolism , Carcinoma, Non-Small-Cell Lung/pathology , Cell Line , Cell Line, Tumor , Enzyme Activation , Frizzled Receptors/genetics , Frizzled Receptors/metabolism , GTP-Binding Protein alpha Subunits, Gq-G11/genetics , Growth Inhibitors/genetics , Humans , Immunoblotting , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Mitogen-Activated Protein Kinase 7/metabolism , Mutation , PPAR gamma/metabolism , RNA Interference , Receptor Tyrosine Kinase-like Orphan Receptors/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Wnt Proteins/genetics , Wnt Proteins/metabolism
19.
J Am Chem Soc ; 127(48): 16955-60, 2005 Dec 07.
Article in English | MEDLINE | ID: mdl-16316241

ABSTRACT

Protein-polymer conjugates are widely used in biotechnology and medicine, and new methods to prepare the bioconjugates would be advantageous for these applications. In this report, we demonstrate that bioactive "smart" polymer conjugates can be synthesized by polymerizing from defined initiation sites on proteins, thus preparing the polymer conjugates in situ. In particular, free cysteines, Cys-34 of bovine serum albumin (BSA) and Cys-131 of T4 lysozyme V131C, were modified with initiators for atom transfer radical polymerization (ATRP) either through a reversible disulfide linkage or irreversible bond by reaction with pyridyl disulfide- and maleimide-functionalized initiators, respectively. Initiator conjugation was verified by electrospray-ionization mass spectroscopy (ESI-MS), and the location of the modification was confirmed by muLC-MSMS (tandem mass spectrometry) analysis of the trypsin-digested protein macroinitiators. Polymerization of N-isopropylacrylamide (NIPAAm) from the protein macroinitiators resulted in thermosensitive BSA-polyNIPAAm and lysozyme-polyNIPAAm in greater than 65% yield. The resultant conjugates were characterized by gel electrophoresis and size exclusion chromatography (SEC) and easily purified by preparative SEC. The identity of polymer isolated from the BSA conjugate was confirmed by (1)H NMR, and the polydispersity index was determined by gel permeation chromatography (GPC) to be as low as 1.34. Lytic activities of the lysozyme conjugates were determined by two standard assays and compared to that of the unmodified enzyme prior to polymerization; no statistical differences in bioactivity were observed.


Subject(s)
Acrylic Resins/chemistry , Muramidase/chemistry , Serum Albumin, Bovine/chemistry , Cysteine/chemistry , Muramidase/metabolism , Spectrometry, Mass, Electrospray Ionization
20.
Org Lett ; 5(3): 281-4, 2003 Feb 06.
Article in English | MEDLINE | ID: mdl-12556172

ABSTRACT

[reaction: see text] The pH-controlled Sharpless asymmetric aminohydroxylation (AA) of styrenes provides 1-aryl-2-amino ethanols (regioisomer B) with high enantio-, chemo-, and regioselectivity. As existing AA protocols typically give regioisomer A as the major reaction product when using carbamate nitrogen sources, this method is a convenient alternative for the selective production of regioisomer B.

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