Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 132
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Int J Immunogenet ; 40(4): 292-8, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23442056

ABSTRACT

Oral squamous cell carcinoma (OSCC) is a worldwide health problem because it is a great cause of cancer morbidity and mortality. The transforming growth factor-ß1 (TGF-ß1) is involved in the regulation of numerous immunomodulatory processes. Thus, the aim of this case-control study was to investigate the possible association between the TGF-ß1T869C polymorphism and oral cancer. The genomic DNA extracted from peripheral blood of 62 male smoker patients diagnosed with OSCC and 62 smokers without cancer was analysed. The C allele was significantly more prevalent in the oral cancer group than in the controls, and individuals carrying this allele had an estimated 2.73-fold greater relative risk of developing cancer compared with C allele noncarriers (OR = 2.73, 95% CI = 1.19-6.28). Although T allele was not statistically significant among the controls, considering the genotypic analysis, the TT homozygous genotype showed a protector effect in relation to oral cavity cancer (OR = 0.37, 95% CI = 0.16-0.84). Some clinicopathological features were also analysed for genotype distribution, and no significant differences were observed: tumour size (P > 0.70), nodal status (P > 0.10) and tumour stage (P > 0.70). This is the first report of a study assessing the importance of T869C TGF-ß polymorphism in oral cancer. It is known that the TGF-ß T869C variation results in a Leu10Pro substitution in the signal peptide sequence. Our results suggested that the C allele could increase TGF-ß secretion which suppresses antitumour immune responses and may affect the OSCC risk.


Subject(s)
Carcinoma, Squamous Cell/genetics , Mouth Neoplasms/genetics , Transforming Growth Factor beta1/genetics , Adult , Alleles , Base Sequence , Carcinoma, Squamous Cell/immunology , Case-Control Studies , Gene Frequency , Genetic Markers , Genetic Predisposition to Disease , Genotype , Humans , Male , Mouth Neoplasms/immunology , Polymorphism, Single Nucleotide , Protein Sorting Signals/genetics , Sequence Analysis, DNA , Smoking
2.
Dis Esophagus ; 26(2): 148-53, 2013.
Article in English | MEDLINE | ID: mdl-22458712

ABSTRACT

A strong association between inactive aldehyde dehydrogenase-2 (ALDH2) and risk of esophageal cancer has been demonstrated in East Asian drinkers. An alcohol flushing questionnaire asking about past and current tendency for facial flushing to occur after drinking a glass (≈180 mL) of beer predicts the presence of inactive ALDH2 among Japanese aged 40 years or older with a sensitivity and specificity of approximately 90%. We invented a health-risk appraisal (HRA) model that makes it possible to identify Japanese men who are at high risk for esophageal cancer based on their past and current alcohol flushing tendency, drinking, smoking, and intake of vegetables and fruits. Between 2008 and 2009, 2221 Japanese men aged 50 years or older filled out the HRA questionnaire before undergoing a screening examination by upper gastrointestinal endoscopy at five medical facilities. The endoscopic examination resulted in a diagnosis of esophageal cancer in 19 subjects, and 117 (5.27%) subjects had an HRA score ≥ 11. The proportion of subjects with an HRA score ≥ 11 was higher in the 50-69 age group (6.11-6.88%) than in 70-89 age group (2.84-2.86%). The esophageal cancer detection rate was 4.27% among the subjects with an HRA score ≥ 11 and only 0.67% among the other subjects. Based on a receiver operating characteristic curve analysis, when an HRA score of ≥ 9 was used for subjects aged 50-69 years and of ≥ 8 for those aged 70-89 years as the cutoff value to select individuals with a high risk for esophageal cancer, its sensitivity and false-positive rate was 52.6% and 15.2%, respectively, and the cancer detection rate was 2.91% in the high-risk group, as opposed to 0.48% in the other group. In conclusion, the high detection rates for esophageal cancer in the high-risk groups encouraged screening based on our HRA model in larger Japanese populations.


Subject(s)
Decision Support Techniques , Early Detection of Cancer/methods , Esophageal Neoplasms/diagnosis , Esophagoscopy , Mass Screening/methods , Aged , Aged, 80 and over , Aldehyde Dehydrogenase/genetics , Aldehyde Dehydrogenase, Mitochondrial , Esophageal Neoplasms/etiology , Esophageal Neoplasms/genetics , False Positive Reactions , Genetic Markers , Humans , Japan , Male , Middle Aged , ROC Curve , Risk Assessment , Risk Factors , Sensitivity and Specificity , Surveys and Questionnaires
3.
Minim Invasive Neurosurg ; 54(1): 1-4, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21506061

ABSTRACT

OBJECTIVE: The aim of this study was to present our experience with retrograde suction decompression in clipping of large and giant cerebral aneurysms and analyze its advantages and pitfalls. METHODS: A retrospective analysis of 27 patients with large and giant intracranial aneurysms treated by suction decompression assisted clipping between November 2005 and February 2010 was done. The surgical technique and the outcome of patients were reviewed. RESULTS: All aneurysms were successfully clipped, and postoperative 3-D CTA or DSA revealed no major branch occlusion or residual aneurysm. There was no surgical mortality in both giant and large aneurysm groups. CONCLUSION: Retrograde suction decompression is a successful adjunct to clipping of large and giant cerebral aneurysms.


Subject(s)
Decompression, Surgical/methods , Intracranial Aneurysm/surgery , Neurosurgical Procedures/methods , Surgical Instruments/statistics & numerical data , Vascular Surgical Procedures/methods , Adult , Aged , Decompression, Surgical/instrumentation , Decompression, Surgical/mortality , Female , Humans , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/pathology , Male , Middle Aged , Neurosurgical Procedures/instrumentation , Neurosurgical Procedures/mortality , Radiography , Retrospective Studies , Suction/instrumentation , Suction/methods , Suction/mortality , Surgical Instruments/standards , Vascular Surgical Procedures/instrumentation , Vascular Surgical Procedures/mortality
4.
AJNR Am J Neuroradiol ; 41(2): 219-223, 2020 02.
Article in English | MEDLINE | ID: mdl-31857330

ABSTRACT

BACKGROUND AND PURPOSE: The newly developed ultra-high-resolution CT is equipped with a 0.25-mm detector, which has one-half the conventional section thickness, one-half the in-plane detector element width, and one-half the reconstructed pixel width compared with conventional-detector CT. Thus, the ultra-high-resolution CT scanner should provide better image quality for microvasculature than the conventional-detector CT scanners. This study aimed to determine whether ultra-high-resolution CT produces superior-quality images of the lenticulostriate arteries compared with conventional-detector CT. MATERIALS AND METHODS: From February 2017 to June 2017, thirteen patients with aneurysms (4 men, 9 women; mean age, 61.2 years) who underwent head CTA with both ultra-high-resolution CT and conventional-detector CT were enrolled. Two board-certified radiologists determined the number of all lenticulostriate arteries on the CTA coronal images of the MCA M1 segment reconstructed from 512 matrixes on conventional-detector CT and 1024 matrixes on ultra-high-resolution CT. RESULTS: There were statistically more lenticulostriate arteries identified on ultra-high-resolution CT (average, 2.85 ± 0.83; 95% CI, 2.509-3.183) than on conventional-detector CT (average, 2.17 ± 0.76; 95% CI, 1.866-2.480) (P = .009) in 16 of the total 26 MCA M1 segments. CONCLUSIONS: Improvements in lenticulostriate artery visualization were the result of the combined package of the ultra-high-resolution CT scanner plus the ultra-high-resolution scanning protocol, which includes higher radiation doses with lower than the national diagnostic reference levels and stronger adaptive iterative dose-reduction processing. This package for ultra-high-resolution CT is a simple, noninvasive, and easily accessible method to evaluate microvasculature such as the lenticulostriate arteries.


Subject(s)
Arteries/diagnostic imaging , Brain/blood supply , Brain/diagnostic imaging , Computed Tomography Angiography/methods , Neuroimaging/methods , Adult , Aged , Female , Humans , Male , Middle Aged , Radionuclide Imaging/methods , Retrospective Studies
6.
Neurogastroenterol Motil ; 29(10): 1-13, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28524628

ABSTRACT

BACKGROUND: Experimental and clinical studies have shown that myenteric neuron cell death during infection with Trypanosoma cruzi mainly occurs in the esophagus and colon, resulting in megaesophagus and megacolon, respectively. Evidence suggests that the cyclooxygenase enzyme (COX) is involved in the T. cruzi invasion process. The use of low-dose aspirin (ASA), a COX-1/COX-2 inhibitor, has been shown to reduce infection with T. cruzi. Therefore, in this study, we evaluated the effects of treatment with low-dose ASA on myenteric colonic neurons during murine infection with T. cruzi. METHODS: Swiss mice were assigned into groups treated with either phosphate-buffered saline or low doses of ASA during the acute phase (20 mg/kg ASA) and chronic phase (50 mg/kg ASA) of infection with the Y strain of T. cruzi. Seventy-five days after infection, colon samples were collected to quantify inflammatory foci in histological sections and also general (myosin-V+ ), nitrergic, and VIPergic myenteric neurons in whole mounts. Gastrointestinal transit time was also measured. KEY RESULTS: Aspirin treatment during the acute phase of infection reduced parasitemia (P<.05). Aspirin treatment during the acute or chronic phase of the infection reduced the intensity of inflammatory foci in the colon, protected myenteric neurons from cell death and plastic changes, and recovered the gastrointestinal transit of mice infected with T. cruzi (P<.05). CONCLUSION & INFERENCES: Early and delayed treatment with low-dose ASA can reduce the morphofunctional damage of colonic myenteric neurons caused by murine T. cruzi infection.


Subject(s)
Aspirin/pharmacology , Chagas Disease/pathology , Cyclooxygenase Inhibitors/pharmacology , Myenteric Plexus/drug effects , Animals , Disease Models, Animal , Male , Mice , Myenteric Plexus/pathology , Neurons/drug effects , Neurons/pathology , Neuroprotective Agents/pharmacology , Trypanosoma cruzi
7.
J Clin Neurosci ; 34: 63-69, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27692502

ABSTRACT

Intraoperative rerupture (IOR) during clipping of cerebral aneurysms is a difficult complication of microneurosurgery. The aim of this study was to evaluate the incidence of IOR and analyze the strategies for controlling profound hemorrhage. A total of 165 patients with unruptured intracranial aneurysms and 46 patients with subarachnoid hemorrhage (SAH) treated surgically between April 2010 and March 2011, were reviewed. The data were collected with regard to age, sex, presence of symptoms, confounding factors and strategy for controlling intraoperative hemorrhage was analyzed in terms of location of aneurysms, timing of rupture and severity of IOR. 211 patients with 228 aneurysms were treated in this series. There were a total of six IORs which represented an IOR rate of 2.84% per patient and 2.63% per aneurysm. The highest ruptures rates occurred in patients with internal carotid artery aneurysms (25%). Surgeries in the group with ruptured aneurysms had a much higher rate of IOR compared with surgeries in the group with unruptured aneurysms. Of the six IOR aneurysms, one occurred during predissection, four during microdissection and one during clipping. One was major IOR, three were moderate and two were minor. Intraoperative rupture of an intracranial aneurysm can be potentially devastating in vascular neurosurgery. Aneurysm location, presence of SAH and surgical experience of the operating surgeon seem to be important factors affecting the incidence of IOR.


Subject(s)
Aneurysm, Ruptured/etiology , Aneurysm, Ruptured/surgery , Intracranial Aneurysm/surgery , Intraoperative Complications/surgery , Neurosurgical Procedures/methods , Adult , Aged , Aneurysm, Ruptured/diagnostic imaging , Angiography, Digital Subtraction , Endovascular Procedures , Female , Humans , Imaging, Three-Dimensional , Incidence , Intracranial Aneurysm/complications , Intracranial Aneurysm/diagnostic imaging , Intracranial Hemorrhages/etiology , Intracranial Hemorrhages/surgery , Intraoperative Complications/diagnostic imaging , Male , Middle Aged , Postoperative Complications/therapy , Subarachnoid Hemorrhage/diagnostic imaging , Subarachnoid Hemorrhage/etiology , Subarachnoid Hemorrhage/surgery , Vision Disorders/etiology , Vision Disorders/therapy
8.
J Mol Biol ; 229(4): 1083-100, 1993 Feb 20.
Article in English | MEDLINE | ID: mdl-8445637

ABSTRACT

Glutathione synthetase (gamma-L-glutamyl-L-cysteine: glycine ligase (ADP-forming) EC 6.3.2.3: GSHase) catalyzes the synthesis of glutathione from gamma-L-glutamyl-L-cysteine and Gly in the presence of ATP. The enzyme from Escherichia coli is a tetramer with four identical subunits of 316 amino acid residues. The crystal structure of the enzyme has been determined by isomorphous replacement and refined to a 2.0 A resolution. Two regions, Gly164 to Gly167 and Ile226 to Arg241, are invisible on the electron density map. The refined model of the subunit includes 296 amino acid residues and 107 solvent molecules. The crystallographic R-factor is 18.6% for 17.914 reflections with F > 3 sigma between 6.0 A and 2.0 A. The structure consists of three domains: the N-terminal, central, and C-terminal domains. In the tetrameric molecule, two subunits that are in close contact form a tight dimer, two tight dimers forming a tetramer with two solvent regions. The ATP molecule is located in the cleft between the central and C-terminal domains. The ATP binding site is surrounded by two sets of the structural motif that belong to those respective domains. Each motif consists of an anti-parallel beta-sheet and a glycine-rich loop.


Subject(s)
Escherichia coli/enzymology , Glutathione Synthase/chemistry , Adenosine Triphosphate/metabolism , Amino Acid Sequence , Binding Sites , Computer Simulation , Cysteine/analysis , Glutathione Synthase/metabolism , Hydrogen Bonding , Models, Molecular , Molecular Sequence Data , Protein Conformation , Protein Folding , Substrate Specificity , X-Ray Diffraction
9.
J Mol Biol ; 286(4): 1137-45, 1999 Mar 05.
Article in English | MEDLINE | ID: mdl-10047487

ABSTRACT

The crystal structure of tobacco PR-5d, an antifungal thaumatin-like protein isolated from cultured tobacco cells, was determined at the resolution of 1.8 A. The structure consists of 208 amino acid residues and 89 water molecules with a crystallographic R-factor of 0.169. The model has good stereochemistry, with respective root-mean-square deviations from the ideal values for bond and angle distances of 0.007 A and 1.542 degrees. Of the homologous PR-5 proteins, only those with antifungal activity had a common motif, a negatively charged surface cleft. This cleft is at the boundary between domains I and II, with a bottom part consisting of a three-stranded antiparallel beta-sheet in domain I. The acidic residues located in the hollow of the cleft form the beta-sheet region. Sequence and secondary structure analyses showed that the amino acid residues comprising the acidic cleft of PR-5d are conserved among other antifungal PR-5 proteins. This is the first report on the high-resolution crystal structure of an antifungal PR-5 protein. This structure provides insight into the function of pathogenesis-related proteins.


Subject(s)
Nicotiana/chemistry , Plant Proteins/chemistry , Plants, Toxic , Sweetening Agents , Amino Acid Sequence , Antifungal Agents/chemistry , Conserved Sequence , Crystallography, X-Ray , Models, Molecular , Molecular Sequence Data , Protein Conformation , Sequence Homology, Amino Acid
10.
J Mol Biol ; 209(3): 503-4, 1989 Oct 05.
Article in English | MEDLINE | ID: mdl-2685323

ABSTRACT

The glutathione synthetase from Escherichia coli B has been crystallized from 27% saturated ammonium sulfate solution (pH 5.5). The crystals are hexagonal, space group P6(2)22 or P6(4)22. The cell dimensions are a = b = 88.0 A, c = 164.2 A, and gamma = 120 degrees. The enzyme is a tetramer (Mr = 143,000) with 222 symmetry, and the asymmetric unit contains one subunit molecule (Mr = 35,600). The crystals diffract to at least 2.5 A resolution.


Subject(s)
Escherichia coli/enzymology , Glutathione Synthase , Peptide Synthases , Crystallization , X-Ray Diffraction
13.
J Clin Neurosci ; 22(1): 69-72, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25443084

ABSTRACT

We present our experience with elective microsurgical clipping of unruptured intracranial aneurysms (UIA) and analyze this management. A total of 150 patients with UIA were reviewed and data were collected with regard to age, sex, presence of symptoms, location and size of the aneurysms, surgical complications and postoperative 1 year outcomes. Aneurysm size was assessed either by three-dimensional CT angiography or digital subtraction angiogram. Glasgow Outcome Scale was used to assess clinical outcomes. One hundred and fifty patients with 165 aneurysms were treated in this series. The mean size of the UIA was 5.6mm. Eighty aneurysms (48.5%) were less than 5mm in size, and 73 (44.2%) were from 5 to 10mm. Ten (6.1%) of the aneurysms were large and two (1.2%) were giant. One hundred and forty-three were asymptomatic and seven were symptomatic before surgery. The outcome was good in 147 patients (98%), and only three patients (2%) had a treatment-related unfavorable outcome. Five patients experienced transient neurological deficits and one patient experienced permanent neurological deficits. Overall 98.7% of the treated aneurysms were satisfactorily obliterated. Wound complications were seen only in three patients. In conclusion, UIA pose a significant challenge for neurosurgeons, where a delicate balance between benefits and possible risks must be weighed. If the requisite expertise is available, they can be treated surgically with low morbidity and a good outcome at specialized neurovascular centers.


Subject(s)
Intracranial Aneurysm/surgery , Microsurgery/methods , Neurosurgical Procedures/methods , Adult , Aged , Female , Follow-Up Studies , Humans , Intracranial Aneurysm/diagnosis , Male , Middle Aged , Neurosurgical Procedures/adverse effects , Treatment Outcome
14.
Int J Radiat Oncol Biol Phys ; 31(4): 921-7, 1995 Feb 15.
Article in English | MEDLINE | ID: mdl-7860407

ABSTRACT

PURPOSE: The feasibility of a concurrent chemoradiotherapeutic protocol for patients with inoperable esophageal squamous cell carcinoma was tested. METHODS AND MATERIALS: Concurrent chemoradiotherapy using protracted low-dose continuous infusions of five-fluorouracil (5-FU; 250-300 mg/m2/24 h) and standard external beam irradiation was given to 28 patients with inoperable esophageal squamous cell carcinoma between November 1991 and June 1993. RESULTS: For 25 patients receiving a total dose of > or = 60 Gy and concurrent 5-FU infusion for more than 5 weeks, the complete response rate was 52%. Local progression-free rate in this chemoradiotherapy group was significantly higher than the historical controls treated by radiotherapy alone (p < 0.05). A multivariate analysis revealed the treatment scheme (concomitant chemoradiotherapy vs. radiotherapy alone) to be a significant factor in local control (p < 0.01). Swallowing pain (39%), anorexia (39%), and nausea (32%) were the most frequent early reactions. Serious late radiation complications have not been observed. CONCLUSION: The concurrent chemoradiotherapy using protracted low-dose continuous infusion of 5-FU and standard radiotherapy is an effective and safe method to obtain a local control in inoperable esophageal squamous cell carcinoma.


Subject(s)
Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/radiotherapy , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/radiotherapy , Fluorouracil/administration & dosage , Aged , Carcinoma, Squamous Cell/mortality , Combined Modality Therapy , Esophageal Neoplasms/mortality , Feasibility Studies , Female , Fluorouracil/adverse effects , Humans , Male , Middle Aged , Pilot Projects , Prospective Studies , Radiotherapy/adverse effects
15.
J Endocrinol ; 150(3): 359-68, 1996 Sep.
Article in English | MEDLINE | ID: mdl-8882154

ABSTRACT

Parathyroid hormone-related protein (PTHrP) is thought to be an important autocrine/paracrine factor for chondrocyte metabolism since mice lacking the PTHrP gene exhibit abnormal cartilage development. To determine the biological role of PTHrP in chondrocytes, we first compared the agonist potency of human (h) PTHrP(1-34) with hPTH(1-34) in cultured rat articular chondrocytes. Neither hPTHrP(1-34) nor hPTH(1-34) altered basal DNA synthesis, but attenuated the stimulatory effect of transforming growth factor beta (TGF-beta). Both agents suppressed the expression of alpha(1) type II collagen mRNA in a dose-response fashion with the same potency. In addition, the action of exogenously added hPTHrP(1-34) and hPTH(1-34) on intracellular cAMP and [Ca2+]i levels was similar. We next compared the effect of PTHrP within its entire amino acid sequence (1-141). With regard to thymidine incorporation, alpha(1) type II collagen gene expression and accumulation of cAMP and [Ca2+]i level, there was no significant difference between hPTHrP(1-34) and hPTHrP(1-141). PTHrP C-terminal (100-114) did not show any function. To further investigate PTHrP function, intracellular PTHrP translation was inhibited by a transgene of antisense oligonucleotides against PTHrP. Antisense oligonucleotides decreased PTHrP mRNA translation, specifically inhibited DNA synthesis in control as well as TGF-beta-treated chondrocytes and enhanced alpha(1) type II collagen mRNA expression in TGF-beta-treated chondrocytes. These results suggest that there is no significant difference between exogenously added hPTH(1-34), hPTHrP(1-34) and PTHrP(1-141) with regard to the biological action of these agents, including cell growth, differentiation and second messenger pathway. However, the result of DNA synthesis in the antisense PTHrP-inhibition study suggests that intracellular PTHrP may have an as yet unknown biological role, in addition to a classical PTH/PTHrP receptor-mediated function in the rat articular chondrocyte.


Subject(s)
Cartilage, Articular/metabolism , Oligonucleotides, Antisense/metabolism , Parathyroid Hormone/metabolism , Proteins/metabolism , Animals , Antihypertensive Agents/metabolism , Base Sequence , Blotting, Northern , Calcium/metabolism , Collagen/metabolism , Cyclic AMP/metabolism , DNA/biosynthesis , DNA Primers/genetics , Molecular Sequence Data , Parathyroid Hormone-Related Protein , Peptide Fragments/metabolism , Polymerase Chain Reaction , Rats , Rats, Sprague-Dawley , Teriparatide/metabolism
16.
Shock ; 14(2): 193-9, 2000 Aug.
Article in English | MEDLINE | ID: mdl-10947166

ABSTRACT

When systemic oxygen delivery (DO2) is reduced, oxygen consumption (VO2) is maintained until a critical level is reached (DO2crit). Sepsis is thought to shift DO2crit to the right and lengthen the supply-dependent portion. We tested the effect of interleukin (IL)-1beta, which is one of the key cytokines related to sepsis, on the DO2-VO2 relationship. Fifteen rabbits were subjected to stepwise cardiac tamponade to reduce DO2 to 10% by inflating a handmade balloon placed into the pericardial sac. Seven rabbits were given 10 microg/kg of IL-1beta intravenously (IL-1beta group) prior to the graded cardiac tamponade. The remainder received saline alone (control group). The DO2-VO2 relationship was analyzed by the dual-line method. IL-1beta significantly decreased mean arterial pressure (65 +/- 11 mmHg from baseline 85 +/- 7 mmHg) without altering cardiac output. The IL-1beta group showed significantly steeper supply-independent line slopes than did the control group (0.19 +/- 0.02 vs. 0.11 +/- 0.02, respectively), which resulted in a DO2crit shift to the left (IL-1beta group, 8.7 +/- 1.7 ml/kg x min vs. control, 11.7 +/- 0.7 ml/kg x min). The IL-1beta group also showed greater PO2 and plasma lactate levels in the portal vein than did the control group. These results indicate that IL-1beta impairs systemic oxygen uptake even before VO2 becomes supply-dependent, presumably due to maldistribution of the blood flow including the splanchnic circulation.


Subject(s)
Cardiac Tamponade/metabolism , Hypoxia/metabolism , Interleukin-1/pharmacology , Oxygen Consumption/drug effects , Oxygen/blood , Shock/metabolism , Animals , Cardiac Tamponade/complications , Female , Humans , Hypotension/chemically induced , Interleukin-1/toxicity , Lactic Acid/blood , Models, Animal , Portal Vein , Rabbits , Recombinant Proteins/pharmacology , Shock/etiology , Splanchnic Circulation
17.
J Neurotrauma ; 18(7): 665-74, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11497093

ABSTRACT

Recent experimental studies have revealed that traumatic brain injury as well as ischemic brain injury can cause chronic progressive neuronal damage. In the present study, we demonstrate previously unreported delayed cerebral atrophy on computerized tomography (CT) scans in severely head-injured patients. Seventeen severely head-injured patients who required mild hypothermia to control intracranial hypertension after the failure of conventional therapies were retrospectively analyzed. All 17 patients survived more than 1 year. Delayed neuronal loss (DNL) was observed in only eight of the 17 patients. Eight patients with DNL required longer durations of mild hypothermia to control intracranial hypertension than nine patients without DNL. Six of these eight patients with DNL achieved functional recovery despite progressive atrophic changes demonstrated on CT scans. On CT scans, DNL was characterized by (1) the sudden appearance at several months postinjury of a low-density area in the hemisphere ipsilateral to the injury; (2) the preservation of essential cortical structure although related white matter structures showed severe atrophic changes; and (3) no spread of the low-density area to the contiguous territory of the other main cerebral artery. It is concluded that focal primary injury to underlying brain, if severe enough, can result in delayed hemispheric atrophy.


Subject(s)
Brain Injuries/complications , Brain/pathology , Neurodegenerative Diseases/etiology , Adolescent , Adult , Aged , Atrophy/diagnostic imaging , Atrophy/etiology , Atrophy/pathology , Brain/diagnostic imaging , Brain Injuries/diagnostic imaging , Brain Injuries/therapy , Child , Female , Follow-Up Studies , Glasgow Coma Scale , Humans , Hypothermia, Induced , Intracranial Hypertension/diagnostic imaging , Intracranial Hypertension/etiology , Intracranial Hypertension/therapy , Magnetic Resonance Imaging , Male , Middle Aged , Neurodegenerative Diseases/diagnostic imaging , Neurodegenerative Diseases/therapy , Outcome Assessment, Health Care , Recovery of Function , Retrospective Studies , Time Factors , Tomography, X-Ray Computed
18.
J Biochem ; 123(1): 136-41, 1998 Jan.
Article in English | MEDLINE | ID: mdl-9504420

ABSTRACT

LipB, the lipase activator protein of Pseudomonas aeruginosa TE3285, was overproduced in Escherichia coli, and purified 4.9-fold over the crude extract in the presence of SDS. The purified LipB reactivated the lipase from P. aeruginosa TE3285 denatured with guanidine hydrochloride, and its reactivation did not involve multiple turnover. In this reactivation, a 1:1 complex between the lipase and LipB was detected in a cross-linking experiment, suggesting that LipB still binds to the lipase after the reactivation. Calcium ion was essential for the complex formation and the reactivation, and addition of EDTA caused inactivation of the reactivated lipase bound to LipB more rapidly than the native lipase. These findings suggest that LipB could affect the calcium binding to the lipase in the reactivation process. LipB was unable to reactivate lipases from other sources except Pseudomonas sp. 109; this lipase has an amino acid sequence which is 98% identical to that of the lipase from P. aeruginosa TE3285. Thus, it may be concluded that LipB specifically recognizes a unique structural element of the lipase.


Subject(s)
Bacterial Proteins/metabolism , Calcium/metabolism , Lipase/metabolism , Pseudomonas/enzymology , Bacterial Proteins/genetics , Bacterial Proteins/isolation & purification , Cross-Linking Reagents , Enzyme Activation , Escherichia coli , Kinetics , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Substrate Specificity
19.
J Biochem ; 101(1): 207-15, 1987 Jan.
Article in English | MEDLINE | ID: mdl-3553173

ABSTRACT

Glutathione synthetase from Escherichia coli B showed amino acid sequence homology with mammalian and bacterial dihydrofolate reductases over 40 residues, although these two enzymes are different in their reaction mechanisms and ligand requirements. The effects of ligands of dihydrofolate reductase on the reaction of E. coli B glutathione synthetase were examined to find resemblances in catalytic function to dihydrofolate reductase. The E. coli B enzyme was potently inhibited by 7,8-dihydrofolate, methotrexate, and trimethoprim. Methotrexate was studied in detail and proved to bind to an ATP binding site of the E. coli B enzyme with K1 value of 0.1 mM. The homologous portion of the amino acid sequence in dihydrofolate reductases, which corresponds to the portion coded by exon 3 of mammalian dihydrofolate reductase genes, provided a binding site of the adenosine diphosphate moiety of NADPH in the crystal structure of dihydrofolate reductase. These analyses would indicate that the homologous portion of the amino acid sequence of the E. coli B enzyme provides the ATP binding site. This report gives experimental evidence that amino acid sequences related by sequence homology conserve functional similarity even in enzymes which differ in their catalytic mechanisms.


Subject(s)
Escherichia coli/enzymology , Glutathione Synthase/analysis , Peptide Synthases/analysis , Tetrahydrofolate Dehydrogenase/analysis , Amino Acid Sequence , Binding Sites , Catalysis , Chromatography, DEAE-Cellulose , Chromatography, Ion Exchange , Electrophoresis, Polyacrylamide Gel , Folic Acid Antagonists , Glutathione Synthase/antagonists & inhibitors , Glutathione Synthase/isolation & purification , Kinetics , Methotrexate/pharmacology , Sodium Dodecyl Sulfate , Tetrahydrofolate Dehydrogenase/isolation & purification
20.
Hypertens Res ; 21(3): 209-13, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9786606

ABSTRACT

We previously proposed that aspirin can enhance the diagnostic sensitivity of renography with [123I] orthoiodohippurate (OIH) in patients with suspected unilateral renovascular hypertension (RVH). In this study we assessed the sensitivity and specificity of this method. Twenty-four patients, 14 with unilateral RVH and 10 with essential hypertension, were studied. For all patients with RVH, definitive diagnosis was based on the results of angiography and the response to renal arterial angioplasty after this study. For all patients with essential hypertension, we confirmed that there was little if any stenosis of the renal artery by digital subtraction angiography or Doppler sonography. Renography with [123I]OIH or 99mTc-mercaptoacetyltriglycine (MAG3) was done once before and once after the oral administration of aspirin (20 mg/kg). We considered renal blood flow to be decreased if the time to the peak in renography was 5 min or more, and defined the peak times of the kidneys as different if separated by 2 min or more. Unilateral RVH was diagnosed when both criteria were met. Renography before aspirin administration indicated RVH in 7 of the 14 patients with RVH, and renography after aspirin indicated RVH in 13 of the 14 patients. Of the 10 patients with essential hypertension, renography before and after aspirin administration showed no difference between the kidneys in 8 patients. Thus, aspirin renography increased the sensitivity from 50% to 93%, but did not change the specificity (80%) in the diagnosis of RVH. These results suggest that renography with [123I]OIH or 99mTc-MAG3 for the diagnosis of unilateral RVH is more sensitive when aspirin is used.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Aspirin/pharmacology , Hypertension, Renovascular/physiopathology , Adult , Aged , Female , Humans , Hypertension, Renovascular/diagnostic imaging , Iodine Radioisotopes , Male , Middle Aged , Radioisotope Renography , Renin/blood
SELECTION OF CITATIONS
SEARCH DETAIL