Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 30
Filter
1.
J Thorac Cardiovasc Surg ; 163(6): 2107-2116.e6, 2022 06.
Article in English | MEDLINE | ID: mdl-34112505

ABSTRACT

OBJECTIVE: To determine characteristics, outcomes, and clinical factors associated with death in patients with COVID-19 requiring extracorporeal membrane oxygenation (ECMO) support. METHODS: A multicenter, retrospective cohort study was conducted. The cohort consisted of adult patients (18 years of age and older) requiring ECMO in the period from March 1, 2020, to September 30, 2020. The primary outcome was in-hospital mortality after ECMO initiation assessed with a time to event analysis at 90 days. Multivariable Cox proportional regression was used to determine factors associated with in-hospital mortality. RESULTS: Overall, 292 patients from 17 centers comprised the study cohort. Patients were 49 (interquartile range, 39-57) years old and 81 (28%) were female. At the end of the follow-up period, 19 (6%) patients were still receiving ECMO, 25 (9%) were discontinued from ECMO but remained hospitalized, 135 (46%) were discharged or transferred alive, and 113 (39%) died during the hospitalization. The cumulative in-hospital mortality at 90 days was 42% (95% confidence interval [CI], 36%-47%). Factors associated with in-hospital mortality were age (adjusted hazard ratio [aHR], 1.31; 95% CI, 1.06-1.61 per 10 years), renal dysfunction measured according to serum creatinine level (aHR, 1.21; 95% CI, 1.01-1.45), and cardiopulmonary resuscitation before ECMO placement (aHR, 1.87; 95% CI, 1.01-3.46). CONCLUSIONS: In patients with severe COVID-19 necessitating ECMO support, in-hospital mortality occurred in fewer than half of the cases. ECMO might serve as a viable modality for terminally ill patients with refractory COVID-19.


Subject(s)
COVID-19 , Extracorporeal Membrane Oxygenation , Respiratory Distress Syndrome , Adolescent , Adult , COVID-19/therapy , Child , Extracorporeal Membrane Oxygenation/adverse effects , Female , Hospital Mortality , Humans , Male , Middle Aged , Retrospective Studies
3.
Ann Surg ; 274(5): e388-e394, 2021 11 01.
Article in English | MEDLINE | ID: mdl-34617934

ABSTRACT

OBJECTIVE: Does extracorporeal membrane oxygenation (ECMO) improve outcomes in ECMO-eligible patients with COVID-19 respiratory failure compared to maximum ventilation alone (MVA)? SUMMARY BACKGROUND DATA: ECMO is beneficial in severe cases of respiratory failure when mechanical ventilation is inadequate. Outcomes for ECMO-eligible COVID-19 patients on MVA have not been reported. Consequently, a direct comparison between COVID-19 patients on ECMO and those on MVA has not been established. METHODS: A total of 3406 COVID-19 patients treated at two major medical centers in Chicago were studied. One hundred ninety-five required maximum ventilatory support, and met ECMO eligibility criteria. Eighty ECMO patients were propensity matched to an equal number of MVA patients using detailed demographic, physiological, and comorbidity data. Primary outcome was survival and disposition at discharge. RESULTS: Seventy-one percent of patients were decannulated from ECMO. Mechanical ventilation was discontinued in 75% ECMO and 16% MVA patients. Twenty-five percent of patients in the ECMO arm expired, 21% while on ECMO, compared with 74% in the MVA cohort. Mortality was significantly lower across all age and BMI groups in the ECMO arm. Sixty-eight percent ECMO and 26% MVA patients were discharged from the hospital. Fewer ECMO patients required long-term rehabilitation. Major complications such as septic shock, ventilator associated pneumonia, inotropic requirements, acute liver and kidney injuries are less frequent among ECMO patients. CONCLUSIONS: ECMO-eligible patients with severe COVID-19 respiratory failure demonstrate a 3-fold improvement in survival with ECMO. They are also in a better physical state at discharge and have lower overall complication rates. As such, strong consideration should be given for ECMO when mechanical ventilatory support alone becomes insufficient in treating COVID-19 respiratory failure.


Subject(s)
COVID-19/therapy , Extracorporeal Membrane Oxygenation/methods , Propensity Score , Respiration, Artificial/methods , Respiratory Insufficiency/therapy , Adult , Aged , COVID-19/complications , COVID-19/epidemiology , Female , Follow-Up Studies , Humans , Male , Middle Aged , Pandemics , Patient Discharge/trends , Respiratory Insufficiency/epidemiology , Respiratory Insufficiency/etiology , Retrospective Studies , SARS-CoV-2 , Severity of Illness Index , Survival Rate/trends , United States/epidemiology , Young Adult
4.
Cureus ; 13(6): e15887, 2021 Jun 24.
Article in English | MEDLINE | ID: mdl-34211814

ABSTRACT

Tumor lysis syndrome (TLS) is an oncological emergency characterized by biochemical abnormalities such as metabolic acidosis, hyperkalemia, hyperphosphatemia, and hypocalcemia. The clinical outcome is directly related to the biochemical abnormalities. TLS can occur in any malignancy, but it is highly associated with rapidly proliferating tumors. Although the syndrome is commonly associated with hematological malignancies, particularly with leukemia and non-Hodgkin's lymphoma, it is rarely seen in patients with Hodgkin's lymphoma. In our case, a 7-year-old girl presented with intermittent fever, non-productive cough, fatigue, and night sweats for four months. On examination, she had an enlarged cervical lymph node of 5 cm in size on the left side accompanied by palpable supraclavicular lymphadenopathy. Past medical history was significant for the relapsing and remitting course of nephrotic syndrome diagnosed two years before presentation. The patient underwent a left-sided cervical node excisional biopsy, which confirmed classical Hodgkin's lymphoma of mixed cellularity type. Her baseline chest x-ray revealed a bulky anterior mediastinal mass. To stage the tumor, a bone marrow biopsy, CT, and positron emission tomography (PET) scan were done. Although the bone marrow biopsy report showed a normal pattern of trilineage hematopoiesis, the CT and PET scan results led to its classification under stage 4. During her stay in the hospital for further work-up and treatment, her condition suddenly deteriorated. There were biochemical derangements on lab reports that confirmed the Spontaneous Tumor Lysis Syndrome (STLS). She recovered completely due to immediate stabilization and correction of electrolyte abnormalities. STLS is a life-threatening condition that is rarely seen in patients with Hodgkin's lymphoma. The treating physicians should be vigilant about this possible sequela of Hodgkin's lymphoma and be aware of its different presentations.

7.
J Indian Soc Periodontol ; 24(1): 54-59, 2020.
Article in English | MEDLINE | ID: mdl-31983846

ABSTRACT

BACKGROUND: The study was designed taking into consideration the drawbacks of periodontal dressing and healing properties of curcumin. The aim was to assess and compare the effect of Curcumin gel (Curenext) and noneugenol periodontal dressing (Coe pak) on tissue response, wound healing in the early stages, and pain post periodontal flap surgery in patients diagnosed with chronic periodontitis. MATERIALS AND METHODS: Twenty patients requiring periodontal flap surgery were allotted to two groups at random, one receiving periodontal dressing and the other receiving curcumin for this cross over split-mouth study. Flap surgeries were performed on 2 quadrants with 3 weeks' interval. After suture removal, postoperative sites were assessed for tissue response (tissue color [TC] and tissue edema [TE]) and early wound healing as primary outcomes of the study. The secondary outcome was pain assessment and the number of analgesics taken by the individuals. RESULTS: The two groups showed no significant differences with respect to tissue response, early wound healing, and pain perception. Curcumin group consumed lesser number of analgesics as compared to the one with periodontal dressing. CONCLUSION: It was confirmed that periodontal dressing and curcumin are effective in reducing the TE, normalizing the TC, enhancing the wound healing and reducing the pain perception. Curcumin can thus be used as an alternative to periodontal dressing.

9.
Handb Clin Neurol ; 158: 205-216, 2018.
Article in English | MEDLINE | ID: mdl-30482348

ABSTRACT

Computed tomography (CT) and magnetic resonance imaging (MRI) have revolutionized the assessment of traumatic brain injury (TBI) by permitting rapid detection and localization of acute intracranial injuries. In concussion, the most common presentation of sports-related head trauma, CT and MRI are unrevealing. This normal appearance of the brain on standard neuroimaging, however, belies the structural and functional pathology that underpins concussion-related symptoms and dysfunction. Advances in neuroimaging have expanded our ability to gain insight into this microstructural and functional brain pathology. This chapter will present both conventional and more advanced imaging approaches (e.g., diffusion tensor imaging, magnetization transfer imaging, magnetic resonance spectroscopy, functional MRI, arterial spin labeling, magnetoencephalography) to the assessment of TBI in sports and discuss some of the current and potential future roles of brain imaging in the assessment of injured athletes.


Subject(s)
Brain Neoplasms/diagnostic imaging , Neuroimaging/methods , Athletic Injuries/complications , Brain Neoplasms/etiology , Humans , Image Processing, Computer-Assisted
10.
J Neurosurg ; 129(6): 1611-1622, 2018 12 01.
Article in English | MEDLINE | ID: mdl-29350598

ABSTRACT

OBJECTIVEThe object of this study was to use diffusion tensor imaging (DTI) and tract-based spatial statistics (TBSS) to characterize the long-term effects of hydrocephalus and shunting on white matter integrity and to investigate the relationship of ventricular size and alterations in white matter integrity with headache and quality-of-life outcome measures.METHODSPatients with shunt-treated hydrocephalus and age- and sex-matched healthy controls were recruited into the study and underwent anatomical and DTI imaging on a 3-T MRI scanner. All patients were clinically stable, had undergone CSF shunt placement before 2 years of age, and had a documented history of complaints of headaches. Outcome was scored based on the Headache Disability Inventory and the Hydrocephalus Outcome Questionnaire. Fractional anisotropy (FA) and other DTI-based measures (axial, radial, and mean diffusivity; AD, RD, and MD, respectively) were extracted in the corpus callosum and internal capsule with manual region-of-interest delineation and in other regions with TBSS. Paired t-tests, corrected with a 5% false discovery rate, were used to identify regions with significant differences between patients and controls. Within the patient group, linear regression models were used to investigate the relationship between FA or ventricular volume and outcome, as well as the effect of shunt-related covariates.RESULTSTwenty-one hydrocephalus patients and 21 matched controls completed the study, and their data were used in the final analysis. The authors found significantly lower FA for patients than for controls in 20 of the 48 regions, mostly posterior white matter structures, in periventricular as well as more distal tracts. Of these 20 regions, 17 demonstrated increased RD, while only 5 showed increased MD and 3 showed decreased AD. No areas of increased FA were observed. Higher FA in specific periventricular white matter tracts, tending toward FA in controls, was associated with increased ventricular size, as well as improved clinical outcome.CONCLUSIONSThe study shows that TBSS-based DTI is a sensitive technique for elucidating changes in white matter structures due to hydrocephalus and chronic CSF shunting and provides preliminary evidence that DTI may be a valuable tool for tailoring shunt procedures to monitor ventricular size following shunting and achieve optimal outcome, as well as for guiding the development of alternate therapies for hydrocephalus.


Subject(s)
Brain/diagnostic imaging , Cerebral Ventricles/diagnostic imaging , Cerebrospinal Fluid Shunts , Diffusion Tensor Imaging , Hydrocephalus/diagnostic imaging , Adolescent , Adult , Brain/surgery , Case-Control Studies , Child , Female , Humans , Hydrocephalus/surgery , Magnetic Resonance Imaging , Male , Young Adult
11.
Cureus ; 8(10): e837, 2016 Oct 19.
Article in English | MEDLINE | ID: mdl-27904817

ABSTRACT

Bertolotti's syndrome (BS) must be considered as a differential diagnosis in a young patient presenting with low back pain (LBP). We present a case of a 26-year-old male complaining of mild chronic LBP for six years, radiating to his left thigh for the past six months. He has been taking non-steroidal anti-inflammatory drugs (NSAIDs) with skeletal muscle relaxants for pain relief. The X-ray and computed tomography (CT) imagings showed congenital enlargement of the left transverse process of the fifth lumbar (L5) vertebra forming pseudo-articulation with the sacrum and unilateral pars interarticularis defect at the L4 level on the left side, respectively. He has managed with gabapentin 100 mg three times a day for his neuropathic left leg pain. On follow-up, the patient reported that his pain has improved with gabapentin and it decreased from 8/10 to 4/10 on the visual analogue scale.

12.
Cureus ; 8(12): e906, 2016 Dec 01.
Article in English | MEDLINE | ID: mdl-28083450

ABSTRACT

We report a case of a 24-year-old female with a history of asthma and gastroesophageal reflux disease (GERD). She presented to the emergency room with severe chest pain, chest tightness, and shortness of breath following an upper respiratory tract infection. The patient reported that she had a cough and runny nose one week prior to this presentation, followed by a sudden sharp pain in the center of the chest 8/10 in intensity on the visual analog scale and pleuritic in nature, which aggravated by deep breathing and lying down flat. It was relieved by sitting up straight and did not radiate to her left arm or jaw. Computed tomography (CT) scan of the chest, posteroanterior and lateral views, showed a mild left pleural effusion with adjacent left basilar atelectasis/infiltrate. CT angiography of the chest with axial contrast showed mild left pleural effusion as well as a small pericardial effusion with bilateral lower lobe interstitial infiltrates. There was no evidence of pulmonary embolism. Electrocardiogram (EKG) showed no apparent ST segment elevation or depression that would be consistent with pericarditis, or acute ischemia or infarct. There was non-specific T wave abnormality. The patient was prescribed prednisone on a tapering dose. On follow-up visit, her condition significantly improved.

13.
PLoS One ; 10(11): e0142288, 2015.
Article in English | MEDLINE | ID: mdl-26580077

ABSTRACT

Registration of subject and control brains to a common anatomical space or template is the basis for quantitatively delineating regions of abnormality in an individual brain. Normally, a brain atlas is chosen as the template. Limitations in the registration process result in persistent differences between individual subject brains and template, which can be a source of error in an analysis. We propose a new approach to the registration process where the subject of interest is the registration template. Through this change, we eliminate errors due to differences between a brain template and a subject's brain. We applied this method to the analysis of FA values derived from DTI data of 20 individual mTBI patients as compared to 48 healthy controls. Subject-centered analysis resulted in identification of significantly fewer regions of abnormally low FA compared to two separate atlas-centered analyses, with subject-centered abnormalities essentially representing the common subset of abnormal low FA regions detected by the two atlas-centered methods. Whereas each atlas-centered approach demonstrated abnormalities in nearly every subject (19/20 and 20/20), the subject-centered approach demonstrated abnormalities in fewer than half the subjects (9/20). This reduction of diffusion abnormalities observed using the subject-centered approach is due to elimination of misregistration errors that occur when registering the subject of interest to a template. Evaluation of atlas-centered analyses demonstrated that 9.8% to 13.3% of subject GM and CSF was misregistered onto the WM of the brain atlas, resulting in the observation of additional low FA clusters compared to the subject-centered approach. Without careful evaluation, these misregistrations could be misinterpreted as pathology. An additional benefit of the subject-centered approach is that diffusion abnormalities can now be visualized directly in the subject's anatomical space, rather than interpolating results from the brain atlas space, and can thereby enhance correlation with other components of an imaging protocol.


Subject(s)
Brain Injuries/diagnostic imaging , Brain/diagnostic imaging , Diffusion Magnetic Resonance Imaging/methods , Diffusion Tensor Imaging , Adolescent , Adult , Aged , Brain/physiopathology , Brain Injuries/cerebrospinal fluid , Brain Injuries/physiopathology , Central Nervous System/diagnostic imaging , Central Nervous System/physiopathology , Female , Humans , Male , Middle Aged , Radiography
14.
Transfusion ; 54(2): 434-44, 2014 Feb.
Article in English | MEDLINE | ID: mdl-23781865

ABSTRACT

BACKGROUND: Red blood cell (RBC) deformation is critical for microvascular perfusion and oxygen delivery to tissues. Abnormalities in RBC deformability have been observed in aging, sickle cell disease, diabetes, and preeclampsia. Although nitric oxide (NO) prevents decreases in RBC deformability, the underlying mechanism is unknown. STUDY DESIGN AND METHODS: As an experimental model, we used ionophore A23187-mediated calcium influx in RBCs to reduce their deformability and investigated the role of NO donor sodium nitroprusside (SNP) and KCa3.1 (Gardos) channel blockers on RBC deformability (measured as elongation index [EI] by microfluidic ektacytometry). RBC intracellular Ca(2+) and extracellular K(+) were measured by inductively coupled plasma mass spectrometry and potassium ion selective electrode, respectively. RESULTS: SNP treatment of RBCs blocked the Ca(2+) (approx. 10 µmol/L)-induced decrease in RBC deformability (EI 0.34 ± 0.02 vs. 0.09 ± 0.01, control vs. Ca(2+) loaded, p < 0.001; and EI 0.37 ± 0.02 vs. 0.30 ± 0.01, SNP vs. SNP plus Ca(2+) loaded) as well as Ca(2+) influx and K(+) efflux. The SNP effect was similar to that observed after pharmacologic blockade of the KCa3.1 channel (with charybdotoxin or extracellular medium containing isotonic K(+) concentration). In RBCs from KCa3.1(-/-) mice, 10 µmol/L Ca(2+) loading did not decrease cellular deformability. A preliminary attempt to address the molecular mechanism of SNP protection suggests the involvement of cell surface thiols. CONCLUSION: Our results suggest that nitroprusside treatment of RBCs may protect them from intracellular calcium increase-mediated stiffness, which may occur during microvascular perfusion in diseased states, as well as during RBC storage.


Subject(s)
Calcimycin/pharmacology , Calcium/metabolism , Erythrocyte Deformability/drug effects , Intermediate-Conductance Calcium-Activated Potassium Channels/antagonists & inhibitors , Nitroprusside/pharmacology , Animals , Blood Donors , Calcium Ionophores/pharmacology , Charybdotoxin/pharmacology , Enzyme Inhibitors/pharmacology , Humans , Intermediate-Conductance Calcium-Activated Potassium Channels/genetics , Iodoacetic Acid/pharmacology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Neurotoxins/pharmacology , Nitric Oxide/metabolism , Nitric Oxide Donors/pharmacology , Potassium/pharmacology
15.
J Indian Soc Periodontol ; 16(2): 253-5, 2012 Apr.
Article in English | MEDLINE | ID: mdl-23055594

ABSTRACT

Periodontal procedures require injection of local anesthetic solution to avoid patient discomfort. Multiple injections are required to anesthetize the anterior maxilla in the region of the premolars to incisors. Anterior middle superior alveolar nerve block is a single palatal injection technique, which anesthetizes the facial and palatal gingiva as well as pulp in the region of the maxillary central incisors to the premolars without any collateral facial anesthesia. This case series presents the application of the anterior middle superior alveolar nerve block in periodontal therapy.

16.
Mol Cell ; 45(1): 13-24, 2012 Jan 13.
Article in English | MEDLINE | ID: mdl-22244329

ABSTRACT

Nuclear factor κB (NF-κB) is an antiapoptotic transcription factor. We show that the antiapoptotic actions of NF-κB are mediated by hydrogen sulfide (H(2)S) synthesized by cystathionine gamma-lyase (CSE). TNF-α treatment triples H(2)S generation by stimulating binding of SP1 to the CSE promoter. H(2)S generated by CSE stimulates DNA binding and gene activation of NF-κB, processes that are abolished in CSE-deleted mice. As CSE deletion leads to decreased glutathione levels, resultant oxidative stress may contribute to alterations in CSE mutant mice. H(2)S acts by sulfhydrating the p65 subunit of NF-κB at cysteine-38, which promotes its binding to the coactivator ribosomal protein S3 (RPS3). Sulfhydration of p65 predominates early after TNF-α treatment, then declines and is succeeded by a reciprocal enhancement of p65 nitrosylation. In CSE mutant mice, antiapoptotic influences of NF-κB are markedly diminished. Thus, sulfhydration of NF-κB appears to be a physiologic determinant of its antiapoptotic transcriptional activity.


Subject(s)
Apoptosis/physiology , Hydrogen Sulfide/chemistry , NF-kappa B/chemistry , Animals , Cystathionine gamma-Lyase/genetics , Cystathionine gamma-Lyase/metabolism , Cystathionine gamma-Lyase/physiology , Gene Expression Regulation , Mice , NF-kappa B/physiology , Sp1 Transcription Factor/metabolism , Transcription Factor RelA/chemistry , Transcription Factor RelA/metabolism , Tumor Necrosis Factor-alpha/physiology
17.
Circ Res ; 109(11): 1259-68, 2011 Nov 11.
Article in English | MEDLINE | ID: mdl-21980127

ABSTRACT

RATIONALE: Nitric oxide, the classic endothelium-derived relaxing factor (EDRF), acts through cyclic GMP and calcium without notably affecting membrane potential. A major component of EDRF activity derives from hyperpolarization and is termed endothelium-derived hyperpolarizing factor (EDHF). Hydrogen sulfide (H(2)S) is a prominent EDRF, since mice lacking its biosynthetic enzyme, cystathionine γ-lyase (CSE), display pronounced hypertension with deficient vasorelaxant responses to acetylcholine. OBJECTIVE: The purpose of this study was to determine if H(2)S is a major physiological EDHF. METHODS AND RESULTS: We now show that H(2)S is a major EDHF because in blood vessels of CSE-deleted mice, hyperpolarization is virtually abolished. H(2)S acts by covalently modifying (sulfhydrating) the ATP-sensitive potassium channel, as mutating the site of sulfhydration prevents H(2)S-elicited hyperpolarization. The endothelial intermediate conductance (IK(Ca)) and small conductance (SK(Ca)) potassium channels mediate in part the effects of H(2)S, as selective IK(Ca) and SK(Ca) channel inhibitors, charybdotoxin and apamin, inhibit glibenclamide-insensitive, H(2)S-induced vasorelaxation. CONCLUSIONS: H(2)S is a major EDHF that causes vascular endothelial and smooth muscle cell hyperpolarization and vasorelaxation by activating the ATP-sensitive, intermediate conductance and small conductance potassium channels through cysteine S-sulfhydration. Because EDHF activity is a principal determinant of vasorelaxation in numerous vascular beds, drugs influencing H(2)S biosynthesis offer therapeutic potential.


Subject(s)
Endothelium, Vascular/metabolism , Hydrogen Sulfide/metabolism , KATP Channels/metabolism , Vasodilation/physiology , Acetylcholine/pharmacology , Animals , Aorta/cytology , Aorta/metabolism , Cells, Cultured/drug effects , Cells, Cultured/metabolism , Charybdotoxin/pharmacology , Cystathionine gamma-Lyase/deficiency , Cystathionine gamma-Lyase/genetics , Endothelium-Dependent Relaxing Factors/metabolism , Female , Glyburide/pharmacology , Hypertension/metabolism , Male , Membrane Potentials/drug effects , Mesenteric Arteries/injuries , Mesenteric Arteries/metabolism , Mesenteric Arteries/pathology , Mice , Mice, Inbred C57BL , Phenylephrine/pharmacology , Potassium Chloride/pharmacology , Rats , Rats, Wistar , Vasodilation/drug effects
18.
Future Oncol ; 7(8): 1007-21, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21823895

ABSTRACT

The use of natural products with therapeutic properties is as ancient as human civilization and for a long time mineral, plant and animal products were the main sources of drugs. Worldwide sales of medicinal plants, crude extracts and finished products amounted to US$15 billion in 1999 and it increased to $23 billion in 2002. More interestingly, the influence of natural products upon anticancer drug discovery and design cannot be underestimated. Approximately 60% of all drugs in clinical trials are either a natural product, compounds derived from natural products or contain pharmacophores derived from active natural products. Thus, even today, in the presence of massive numbers of agents from combinatorial libraries, compounds from natural sources are still in the forefront of cancer chemotherapeutics as sources of active drug types, as well as being involved in drug discovery in diseases such as microbial and parasitic infections and the control of cholesterol/lipids, among other functions.


Subject(s)
Antineoplastic Agents, Phytogenic/therapeutic use , Biological Products/therapeutic use , Neoplasms/drug therapy , Neoplasms/metabolism , Signal Transduction/drug effects , Antineoplastic Agents, Phytogenic/pharmacology , Biological Products/pharmacology , Cell Survival/drug effects , Humans
19.
Proc Natl Acad Sci U S A ; 108(6): 2205-9, 2011 Feb 08.
Article in English | MEDLINE | ID: mdl-21262846

ABSTRACT

The inositol pyrophosphate, diphosphoinositol pentakisphosphate, regulates p53 and protein kinase Akt signaling, and its aberrant increase in cells has been implicated in apoptosis and insulin resistance. Inositol hexakisphosphate kinase-2 (IP6K2), one of the major inositol pyrophosphate synthesizing enzymes, mediates p53-linked apoptotic cell death. Casein kinase-2 (CK2) promotes cell survival and is upregulated in tumors. We show that CK2 mediated cell survival involves IP6K2 destabilization. CK2 physiologically phosphorylates IP6K2 at amino acid residues S347 and S356 contained within a PEST sequence, a consensus site for ubiquitination. HCT116 cells depleted of IP6K2 are resistant to cell death elicited by CK2 inhibitors. CK2 phosphorylation at the degradation motif of IP6K2 enhances its ubiquitination and subsequent degradation. IP6K2 mutants at the CK2 sites that are resistant to CK2 phosphorylation are metabolically stable.


Subject(s)
Apoptosis , Casein Kinase II/metabolism , Gene Expression Regulation, Enzymologic , Phosphotransferases (Phosphate Group Acceptor)/metabolism , Signal Transduction , Up-Regulation , Amino Acid Motifs , Cell Survival , Enzyme Stability , Gene Expression Regulation, Neoplastic , HEK293 Cells , HeLa Cells , Humans , Insulin Resistance , Neoplasms/enzymology , Phosphorylation , Proto-Oncogene Proteins c-akt/metabolism , Tumor Suppressor Protein p53/metabolism , Ubiquitination
20.
J Indian Soc Periodontol ; 14(1): 8-11, 2010 Jan.
Article in English | MEDLINE | ID: mdl-20922072

ABSTRACT

BACKGROUND: Neutrophils constitute the main phagocytic cell system in mammalian host defense against an infecting agent. Abnormalities in leukocyte number and function are associated with increased susceptibility to periodontal diseases. The purpose of this study is to evaluate the in vitro phagocytic properties of crevicular and peripheral blood neutrophils in healthy and periodontitis subjects. PATIENTS AND METHODS: A total of 30 subjects, that is, 10 patients in each of the following three groups: healthy controls, chronic periodontitis (CP), and localized aggressive periodontitis (LAP), were included in the study. The neutrophils were isolated from the peripheral blood and gingival crevice and tested for phagocytosis of Candida albicans. The percentage of leukocytes with ingested C. albicans was determined by light microscopy. RESULTS: A significant reduction in the phagocytic activity of crevicular fluid polymorphonuclear neutrophils (CF-PMN) of LAP subjects (mean: 54.3±7)(P<0.001) was observed, compared to healthy controls (mean: 74.2±9) and chronic periodontitis subjects (mean: 69±9)(P=0.352). The mean percentage of peripheral blood polymorphonuclear neutrophils (PMNs) with phagocytosis of opsonized C. albicans in LAP patients was significantly reduced (mean: 74.9±5)(P<0.0068) compared to the phagocytic activity of neutrophils from controls (mean:82.1±3) and chronic periodontitis subjects (mean: 82.0±5)(P=0.970). There was no significant reduction in the phagocytic activity of CF PMNs (mean: 69±9) (P=0.35) and peripheral blood PMNs (mean: 82.5)(P=0.97) in the chronic periodontitis group when compared to the control group. CONCLUSION: The phagocytic activity of both crevicular and peripheral neutrophils in subjects with periodontitis is altered, increasing the susceptibility to periodontitis. Thus individual susceptibility may be an additional and important modifying factor in the pathogenesis of periodontal disease.

SELECTION OF CITATIONS
SEARCH DETAIL
...