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1.
Zhonghua Bing Li Xue Za Zhi ; 51(9): 838-842, 2022 Sep 08.
Article in Zh | MEDLINE | ID: mdl-36097899

ABSTRACT

Objective: To investigate the expression of Ki-67 and CD34 in the differential diagnosis of ductal carcinoma in situ (DCIS) and DCIS-like invasive breast cancer (DLIBC). Methods: A total of 100 cases of DCIS and 150 cases of DLIBC diagnosed pathologically in Yantai Yuhuangding Hospital from January 2019 to March 2022 were collected. The expression of p63, CK5/6, Ki-67 and CD34 in both groups were detected by immunohistochemical (IHC) staining and evaluated. Results: The 100 cases of DCIS included 11 cases of low-grade DCIS, 28 cases of intermediate-grade DCIS and 61 cases of high-grade DCIS. IHC staining of p63 and CK5/6 showed the myoepithelial cells around cancerous duct were complete or partial absence. Ki-67 expression showed two patterns: high expression in the basal layers and scattered expression within the tumor. Most cases showed mainly high basal expression (77/100, 77%), and the proportion of this pattern was significantly different between low grade and high grade DCIS (P<0.05). All cases showed complete CD34 expression surrounding the cancerous duct with different proportion (vascular necklace) suggested small vessels proliferation. The 150 cases of DLIBC included 142 cases of invasive ductal carcinoma (IDC) (three cases of basal-like breast cancer was included), two cases of secretory carcinoma, three cases of solid papillary carcinoma, two cases of adenoid cystic carcinoma and one case of acinar cell carcinoma. Among 142 cases of IDC, 13 cases were grade Ⅰ, 77 were grade Ⅱ and 52 were grade Ⅲ. IHC staining of p63 showed complete absence of myoepithelium. CK5/6 was negative in most cases and only positively expressed within the tumor in 3 cases of basal-like breast cancer. Ki-67 indicated a scattered expression pattern within the tumor. In most cases, CD34 immunostaining showed scattered positive blood vessels within the tumor while only two cases showed incomplete expression of CD34 around the tumor (2/150, 1.3%). The different expression patterns of Ki-67 and CD34 in DCIS and DLIBC was statistically significant (P<0.05). Conclusions: The different expression patterns of Ki-67 and CD34 are helpful to distinguish DLIBC from DCIS. The appearance of "vascular necklace" with CD34 and the high expression of Ki-67 around the cancerous duct highly support the diagnosis of DCIS, and the scattered expression pattern of CD34 supports DLIBC.


Subject(s)
Breast Neoplasms , Carcinoma, Ductal, Breast , Carcinoma, Intraductal, Noninfiltrating , Neuroblastoma , Antigens, CD34 , Breast Neoplasms/pathology , Carcinoma, Ductal, Breast/pathology , Carcinoma, Intraductal, Noninfiltrating/pathology , Cell Adhesion Molecules , Female , Humans , Immunohistochemistry , Ki-67 Antigen
2.
Haemophilia ; 24(2): 211-220, 2018 Mar.
Article in English | MEDLINE | ID: mdl-28815880

ABSTRACT

INTRODUCTION: Nuwiq® (Human-cl rhFVIII) is a fourth generation recombinant FVIII, produced in a human cell line, without chemical modification or protein fusion. No inhibitors developed in studies with Nuwiq® in 201 previously treated patients with haemophilia A (HA). The immunogenicity, efficacy and safety of Nuwiq® in previously untreated patients (PUPs) with severe HA are being assessed in the ongoing NuProtect study. METHODS: The study, conducted across 38 centres worldwide, is evaluating 110 true PUPs of all ages and ethnicities enrolled for study up to 100 exposure days (EDs) or 5 years maximum. The primary objective is to assess the immunogenicity of Nuwiq® (inhibitor activity ≥0.6 BU) using the Nijmegen-modified Bethesda assay at a central laboratory. RESULTS: Data for 66 PUPs with ≥20 EDs from a preplanned interim analysis were analysed. High-titre (HT) inhibitors developed in 8 of 66 patients after a median of 11.5 EDs (range 6-24). Five patients developed low-titre inhibitors (4 transient). The cumulative incidence (95% confidence interval) was 12.8% (4.5%, 21.2%) for HT inhibitors and 20.8% (10.7%, 31.0%) for all inhibitors. During inhibitor-free periods, median annualized bleeding rates during prophylaxis were 0 for spontaneous bleeds and 2.40 for all bleeds. Efficacy was rated as "excellent" or "good" in treating 91.8% of bleeds. Efficacy of surgical prophylaxis was "excellent" or "good" for 8 (89%) procedures and "moderate" for 1 (11%). No tolerability concerns were evident. CONCLUSION: These interim data show a cumulative incidence of 12.8% for HT inhibitors and convincing efficacy and tolerability in PUPs treated with Nuwiq® .


Subject(s)
Hemophilia A/immunology , Adolescent , Adult , Animals , Child , Child, Preschool , Dogs , Humans , Prospective Studies , Young Adult
3.
Strahlenther Onkol ; 188(1): 77-83, 2012 Jan.
Article in English | MEDLINE | ID: mdl-22194024

ABSTRACT

PURPOSE: The accurate volumetric calculation of moving targets/organs is required to use cone-beam computed tomography (CBCT) for replanning purposes. This study was aimed to correct the reconstructed volume losses of moving phantoms by phase-specific CBCT. MATERIALS AND METHODS: Planning fan-beam CT (FBCT) of five hepatobiliary/gastrointestinal/pancreatic cancer patients were acquired under active breathing control and compared with free-breathing CBCT for kidney volumes. Three different-sized ball phantoms were scanned by FBCT and CBCT. Images were imported to a planning system to compare the reconstructed volumes. The phantoms were moved longitudinally on an oscillator with different amplitudes/frequencies. The phase-specific projections of CBCT for moving phantoms were selected for volume reconstruction. RESULTS: The differences in reconstructed volumes of static small, medium, large phantoms between FBCT and CBCT were - 6.7%, - 2.3%, and - 2.0%, respectively. With amplitudes of 7.5-20 mm and frequencies of 8-16 oscillations/min, volume losses on CBCT were comparable with FBCT in large moving phantoms (range 9.1-27.2%). Amplitudes were more subject to volume losses than frequencies. On phase-specific CBCT, volume losses were reduced to 2.3-6.5% by reconstruction using 2-3 projections at end/midoscillation phase. CONCLUSION: Amplitude had more impact than frequency on volume losses of moving phantoms on CBCT. Phase-specific CBCT reduced volume losses.


Subject(s)
Cone-Beam Computed Tomography/methods , Image Processing, Computer-Assisted/methods , Neoplasms/radiotherapy , Phantoms, Imaging , Radiotherapy Planning, Computer-Assisted/methods , Respiration , Artifacts , Biliary Tract Neoplasms/radiotherapy , Gastrointestinal Neoplasms/radiotherapy , Humans , Liver Neoplasms/radiotherapy , Organ Size , Pancreatic Neoplasms/radiotherapy , Sensitivity and Specificity
6.
J Thromb Haemost ; 4(6): 1228-36, 2006 Jun.
Article in English | MEDLINE | ID: mdl-16706965

ABSTRACT

BACKGROUND: Prophylactic treatment for severe hemophilia A is likely to be more effective than treatment when bleeding occurs, however, prophylaxis is costly. We studied an inception cohort of 25 boys using a tailored prophylaxis approach to see if clotting factor use could be reduced with acceptable outcomes. METHODS: Ten Canadian centers enrolled subjects in this 5-year study. Children were followed every 3 months at a comprehensive care hemophilia clinic. They were initially treated with once-weekly clotting factor; the frequency was escalated in a stepwise fashion if unacceptable bleeding occurred. Bleeding frequency, target joint development, physiotherapy and radiographic outcomes, as well as resource utilization, were determined prospectively. RESULTS: The median follow-up time was 4.1 years (total 96.9 person-years). The median time to escalate to twice-weekly therapy was 3.42 years (lower 95% confidence limit 2.05 years). Nine subjects developed target joints at a rate of 0.09 per person-year. There was an average of 1.2 joint bleeds per person-year. The cohort consumed on average 3656 IU kg(-1)year(-1) of factor (F) VIII. Ten subjects required central venous catheters (three while on study); no complications of these devices were seen. One subject developed a transient FVIII inhibitor. End-of-study joint examination scores--both clinically and radiographically--were normal or near-normal. CONCLUSIONS: Most boys with severe hemophilia A will probably have little bleeding and good joint function with tailored prophylaxis, while infusing less FVIII than usually required for traditional prophylaxis.


Subject(s)
Factor VIII/therapeutic use , Hemarthrosis/prevention & control , Hemophilia A/drug therapy , Canada , Child, Preschool , Disease Progression , Dose-Response Relationship, Drug , Drug Administration Schedule , Factor VIII/administration & dosage , Hemarthrosis/etiology , Hemarthrosis/pathology , Hemophilia A/complications , Hemophilia A/pathology , Humans , Infant , Joints/pathology , Male , Patient Compliance , Patient Satisfaction , Prospective Studies
7.
Cochrane Database Syst Rev ; (2): CD003429, 2006 Apr 19.
Article in English | MEDLINE | ID: mdl-16625581

ABSTRACT

BACKGROUND: People with severe hemophilia A or B, X-linked bleeding disorders due to decreased blood levels of coagulants, suffer recurrent bleeding into joints and soft tissues. Before clotting factor concentrates were available, most people with severe hemophilia developed crippling musculoskeletal deformities. Clotting factor concentrate prophylaxis aims to preserve joint function by converting severe hemophilia (factor VIII or IX less than 1%) into a clinically milder form of the disease. Prophylaxis has long been used in Sweden, but not universally adopted because of medical, psychosocial, and cost controversies. Use of clotting factor concentrates is the single largest predictor of cost in treating hemophilia. OBJECTIVES: To determine the effectiveness of clotting factor concentrate prophylaxis in the management of people with hemophilia A or B. SEARCH STRATEGY: We searched the Cystic Fibrosis and Genetic Disorders Group's Trials Register comprising references from comprehensive electronic database searches and handsearches of journals and abstract books. Reference lists of relevant articles were reviewed. Most recent search: November 2005. SELECTION CRITERIA: Randomized controlled trials (RCTs) evaluating people with severe hemophilia A or B, receiving prophylactic clotting factor concentrates. DATA COLLECTION AND ANALYSIS: Two authors independently reviewed studies for eligibility, assessed methodological quality and extracted data. MAIN RESULTS: Twenty-nine studies were identified; four studies (including 37 participants) were eligible for inclusion. Three studies evaluated hemophilia A; one showed a decrease in frequency of joint bleeds with prophylaxis compared to placebo (non-physiological dose), with a rate difference (RD) -10.80 (95% confidence interval (CI) -16.33 to -5.27) bleeds per year. The remaining two studies evaluating hemophilia A compared two prophylaxis regimens, one study showed no difference in joint bleed frequency, RD -5.04 (95%CI -17.02 to 6.94) bleeds per year and another failed to demonstrate an advantage of factor VIII dosing based on individual pharmacokinetic data over the standard prophylaxis regimen with RD -0.14 (95% CI -1.34 to 1.05) bleeds per year. The fourth study evaluated hemophilia B and showed fewer joint bleeds with weekly (15 IU/kg) versus bi-weekly (7.5 IU/kg) prophylaxis, RD -3.30 (95% CI -5.50 to - 1.10) bleeds per year. AUTHORS' CONCLUSIONS: There is insufficient evidence from randomised controlled trials to determine whether prophylactic clotting factor concentrates decrease bleeding and bleeding-related complications in hemophilia A or B, compared to placebo, on-demand treatment, or prophylaxis based on pharmacokinetic data from individuals. Well-designed RCTs are needed to assess the effectiveness of prophylactic clotting factor concentrates. Two clinical trials are ongoing.


Subject(s)
Blood Coagulation Factors/therapeutic use , Factor VIII/therapeutic use , Hemarthrosis/prevention & control , Hemophilia A/complications , Hemophilia B/complications , Humans , Randomized Controlled Trials as Topic
8.
Cancer Res ; 50(10): 3032-5, 1990 May 15.
Article in English | MEDLINE | ID: mdl-2185878

ABSTRACT

Overexpression of oncogenes has been associated with the pathogenesis of some human cancers. The ros oncogene, which encodes a putative receptor with tyrosine kinase activity, has been recently shown to be specifically expressed in high levels in human astrocytoma and glioblastoma cell lines. Using transcription mapping analysis, we surveyed 25 primary astrocytomas of all histological grades, including glioblastomas, and failed to demonstrate elevated expression of ros in these tumors. This difference between the cell lines and the primary tumors may be due to dilution of the ros-positive clones by larger populations of ros-negative cells in the primary tumors or to induction of ros oncogene when the tumors are adapted to tissue culture.


Subject(s)
Astrocytoma/genetics , Glioma/genetics , Oncogenes , Proto-Oncogene Proteins/genetics , Receptor Protein-Tyrosine Kinases , Blotting, Southern , Cell Line , DNA Probes , Gene Expression , Genes, Neoplasm , Humans , Protein-Tyrosine Kinases , RNA, Messenger/genetics , RNA, Neoplasm/genetics , Restriction Mapping
9.
Oncogene ; 12(7): 1417-23, 1996 Apr 04.
Article in English | MEDLINE | ID: mdl-8622857

ABSTRACT

Microsatellite instability, as shown by the presence of additional alleles or shifts of electrophoretic mobility at simple sequence tandem repeat loci, has been demonstrated in hereditary and sporadic colorectal tumors and many other tumor types. To study microsatellite instability in human brain tumors, we examined a total of 144 sporadic neoplasms. These included 33 astrocytic tumors, 23 oligodendrogliomas, six gangliogliomas, 41 meningiomas, 10 vestibular schwannomas and 31 pituitary adenomas. Di-, tri- and tetranucleotide repeat microsatellite markers localized on chromosome 4 and 9, X, 13 and 22, respectively, were used to assess whether instability was a significant aspect of their abnormal chromosomal pattern. Instability of microsatellite markers was detected in four oligodendrogliomas (17.4%), one pituitary adenoma (3.2%), one meningioma (2.4%), one astrocytic tumor (3.0%) and not at all in gangliogliomas and schwannomas. Therefore, our results suggest that the microsatellite instability which occurs in colorectal cancers with defective mismatch repair is infrequent in many types of human brain tumors and that the lower level of instability observed in brain tumors may be reflective of other mechanisms of genetic instability.


Subject(s)
Brain Neoplasms/genetics , DNA, Satellite , Base Sequence , Brain Neoplasms/pathology , DNA Primers , Genetic Markers , Humans , Microsatellite Repeats , Molecular Sequence Data
10.
Chem Biol ; 5(4): 185-96, 1998 Apr.
Article in English | MEDLINE | ID: mdl-9545432

ABSTRACT

BACKGROUND: High level resistance to carbapenem antibiotics in gram negative bacteria such as Bacteroides fragilis is caused, in part, by expression of a wide-spectrum metallo-beta-lactamase that hydrolyzes the drug to an inactive form. Co-administration of metallo-beta-lactamase inhibitors to resistant bacteria is expected to restore the antibacterial activity of carbapenems. RESULTS: Biphenyl tetrazoles (BPTs) are a structural class of potent competitive inhibitors of metallo-beta-lactamase identified through screening and predicted using molecular modeling of the enzyme structure. The X-ray crystal structure of the enzyme bound to the BPT L-159,061 shows that the tetrazole moiety of the inhibitor interacts directly with one of the two zinc atoms in the active site, replacing a metal-bound water molecule. Inhibition of metallo-beta-lactamase by BPTs in vitro correlates well with antibiotic sensitization of resistant B. fragilis. CONCLUSIONS: BPT inhibitors can sensitize a resistant B. fragilis clinical isolate expressing metallo-beta-lactamase to the antibiotics imipenem or penicillin G but not to rifampicin.


Subject(s)
Bacteroides fragilis/drug effects , Biphenyl Compounds/pharmacology , Carbapenems/metabolism , Enzyme Inhibitors/pharmacology , Tetrazoles/pharmacology , beta-Lactamase Inhibitors , Bacteroides fragilis/enzymology , Biphenyl Compounds/chemistry , Carbapenems/pharmacology , Crystallography, X-Ray , Drug Interactions , Enzyme Inhibitors/chemistry , Models, Molecular , Protein Conformation , Structure-Activity Relationship , Tetrazoles/chemistry , beta-Lactam Resistance , beta-Lactamases/chemistry , beta-Lactamases/drug effects , beta-Lactamases/metabolism
11.
Cochrane Database Syst Rev ; (2): CD003429, 2005 Apr 18.
Article in English | MEDLINE | ID: mdl-15846666

ABSTRACT

BACKGROUND: People with severe hemophilia A or B, X-linked bleeding disorders due to decreased blood levels of coagulants, suffer recurrent bleeding into joints and soft tissues. Before clotting factor concentrates were available, most people with severe hemophilia developed crippling musculoskeletal deformities. Clotting factor concentrate prophylaxis aims to preserve joint function by converting severe hemophilia (factor VIII or IX less than 1%) into a clinically milder form of the disease. Prophylaxis has long been used in Sweden, but not universally adopted because of medical, psychosocial, and cost controversies. Use of clotting factor concentrates is the single largest predictor of cost in treating hemophilia. OBJECTIVES: To determine the effectiveness of clotting factor concentrate prophylaxis in the management of people with hemophilia A or B. SEARCH STRATEGY: We searched the Cystic Fibrosis and Genetic Disorders Group's Trials Register comprising references from comprehensive electronic database searches and handsearches of journals and abstract books. Reference lists of relevant articles were reviewed. Most recent search: January 2002. SELECTION CRITERIA: Randomized controlled trials (RCTs) evaluating people with severe hemophilia A or B, receiving prophylactic clotting factor concentrates. DATA COLLECTION AND ANALYSIS: Two reviewers independently reviewed studies for eligibility, assessed methodological quality and extracted data. MAIN RESULTS: Twenty-nine studies were identified, of which four (including 37 participants) were eligible for inclusion. Three studies evaluated hemophilia A; one showed a decrease in frequency of joint bleeds with prophylaxis compared to placebo (non-physiological dose), with a rate difference (RD) -10.80 (95% confidence interval (CI) -16.33 to -5.27) bleeds per year. The remaining two studies evaluating hemophilia A compared two prophylaxis regimens, one study showed no difference in joint bleed frequency, RD -5.04 (95%CI -17.02 to 6.94) bleeds per year and another failed to demonstrate an advantage of factor VIII dosing based on individual pharmacokinetic data over the standard prophylaxis regimen with RD -0.14 (95% CI -1.34 to 1.05) bleeds per year. The fourth study evaluated hemophilia B and showed fewer joint bleeds with weekly (15 IU/kg) versus bi-weekly (7.5 IU/kg) prophylaxis, RD -3.30 (95% CI -5.50 to - 1.10) bleeds per year. AUTHORS' CONCLUSIONS: There is insufficient evidence to determine whether prophylactic clotting factor concentrates decrease bleeding and bleeding-related complications in hemophilia A or B, compared to placebo, on-demand treatment, or prophylaxis based on pharmacokinetic data from individuals. Well-designed RCTs are needed to assess the effectiveness of prophylactic clotting factor concentrates. Two clinical trials are ongoing.


Subject(s)
Blood Coagulation Factors/therapeutic use , Hemarthrosis/prevention & control , Hemophilia A/complications , Hemophilia B/complications , Factor VIII/therapeutic use , Humans , Randomized Controlled Trials as Topic
12.
Neurology ; 43(1): 216-8, 1993 Jan.
Article in English | MEDLINE | ID: mdl-8423891

ABSTRACT

Downbeat nystagmus (DBN) uncommonly occurs as a transient phenomenon, and it rarely occurs in patients with cerebrovascular disease. We observed a patient with intermittent DBN and lightheadedness due to transient obstruction of his dominant vertebral artery when he turned his head to his left side. Surgical removal of an osteophyte at the site of the angiographically demonstrated lesion relieved his symptoms.


Subject(s)
Cervical Vertebrae , Nystagmus, Pathologic/etiology , Spinal Osteophytosis/complications , Vertebrobasilar Insufficiency/complications , Cervical Vertebrae/diagnostic imaging , Constriction, Pathologic/etiology , Humans , Male , Middle Aged , Spinal Osteophytosis/diagnostic imaging , Tomography, X-Ray Computed , Vertebrobasilar Insufficiency/diagnostic imaging
13.
J Immunol Methods ; 192(1-2): 37-41, 1996 Jun 10.
Article in English | MEDLINE | ID: mdl-8699020

ABSTRACT

The lysis of susceptible targets by efficient cytotoxic T lymphocytes (CTL) increases both with time and with the ratio of CTL to target. Simple methods for calculating a killing rate constant from the time dependence of killing and for calculating the relation of the killing rate constant to the concentration of exocytosable granzyme A are given. Application of these methods to the killing of target cells by the highly efficient mouse CTL AR1 is presented. AR1 needed granzyme A for efficient killing. AR1 contained sufficient exocytosable granzyme A to kill at about 80% of the rate possible at infinite exocytosable granzyme A.


Subject(s)
Cytotoxicity, Immunologic , Exocytosis/immunology , Serine Endopeptidases/metabolism , T-Lymphocytes, Cytotoxic/enzymology , T-Lymphocytes, Cytotoxic/immunology , Animals , Cell Line , Cytotoxicity Tests, Immunologic , Granzymes , Kinetics , Mice , Serine Endopeptidases/immunology
14.
Int J Radiat Oncol Biol Phys ; 43(2): 455-67, 1999 Jan 15.
Article in English | MEDLINE | ID: mdl-10030275

ABSTRACT

PURPOSE: To develop and implement a non-invasive immobilization system guided by a dedicated quality assurance (QA) program for dynamic intensity-modulated radiotherapy (IMRT) of intracranial and head and neck disease, with IMRT delivered using the NOMOS Corporation's Peacock System and MIMiC collimator. METHODS AND MATERIALS: Thermoplastic face masks are combined with cradle-shaped polyurethane foaming agents and a dedicated quality assurance program to create a customized headholder system (CHS). Plastic shrinkage was studied to understand its effect on immobilization. Fiducial points for computerized tomography (CT) are obtained by placing multiple dabs of barium paste on mask surfaces at intersections of laser projections used for patient positioning. Fiducial lines are drawn on the cradle along laser projections aligned with nasal surfaces. Lateral CT topograms are annotated with a crosshair indicating the origin of the treatment planning and delivery coordinate system, and with lines delineating the projections of superior-inferior field borders of the linear accelerator's secondary collimators, or with those of the fully open MIMiC. Port films exposed with and without the MIMIC are compared to annotated topograms to measure positional variance (PV) in superior-inferior (SI), right-left (RL), and anterior posterior (AP) directions. MIMiC vane patterns superposed on port films are applied to verify planned patterns. A 12-patient study of PV was performed by analyzing positions of 10 anatomic points on repeat CT topograms, plotting histograms of PV, and determining average PV. RESULTS AND DISCUSSION: A 1.5+/-0.3 mm SD shrinkage per 70 cm of thermoplastic was observed over 24 h. Average PV of 1.0+/-0.8, 1.2+/-1.1, and 1.3+/-0.8 mm were measured in SI, AP, and RL directions, respectively. Lateral port films exposed with and without the MIMiC showed PV of 0.2+/-1.3 and 0.8+/-2.2 mm in AP and SI directions. Vane patterns superimposed on port films consistently verified the planned patterns. CONCLUSION: The CHS provided adequately reproducible immobilization for dynamic IMRT, and may be applicable to decrease PV for other cranial and head and neck external beam radiation therapy.


Subject(s)
Brain Neoplasms/radiotherapy , Head and Neck Neoplasms/radiotherapy , Immobilization , Masks , Radiotherapy Planning, Computer-Assisted/methods , Brain Neoplasms/diagnostic imaging , Equipment Design , Head and Neck Neoplasms/diagnostic imaging , Humans , Masks/standards , Quality Control , Restraint, Physical/instrumentation , Tomography, X-Ray Computed
15.
Int J Radiat Oncol Biol Phys ; 40(5): 1213-30, 1998 Mar 15.
Article in English | MEDLINE | ID: mdl-9539579

ABSTRACT

PURPOSE: To verify that optimized dose distributions provided by an intensity-modulated radiation therapy (IMRT) system are delivered accurately to human patients. METHODS AND MATERIALS: Anthropomorphic phantoms are used to measure IMRT doses. Four types of verification are developed for: I) system commissioning with beams optimized to irradiate simulated targets in phantoms, II) plans with patient-optimized beams directed to phantoms simulating the patient, III) patient-phantom hybrid plans with patient-optimized beams calculated in phantom without further optimization, and IV) in vivo measurements. Phantoms containing dosimeters are irradiated with patient-optimized beams. Films are scanned and data were analyzed with software. Percent difference between verified and planned maximum target doses is defined as "dose discrepancy" (deltavp). The frequency distribution of type II deltavp from 204 verification films of 92 IMRT patients is fit to a Gaussian. Measurements made in vivo yield discrepancies specified as deltaivp, also fit to a Gaussian. RESULTS AND DISCUSSION: Verification methods revealed three systematic errors in plans that were corrected prior to treatment. Values of [deltavp] for verification type I are <2%. Type II verification discrepancies are characterized by a Gaussian fit with a peak 0.2% from the centroid, and 158 [deltavp] <5%. The 46 values of [deltavp] >5% arise from differences between phantom and patient geometry, and from simulation, calculation, and other errors. Values of [deltavp] for verification III are less than half of the values of [deltavp] for verification II. A Gaussian fit of deltaivp from verification IV shows more discrepancy than the fit of deltavp, attributed to dose gradients in detectors, and exacerbated by immobilization uncertainty. CONCLUSIONS: Dosimetric verification is a critical step in the quality assurance (QA) of IMRT. Hybrid Verification III is suggested as a preliminary quality standard for IMRT.


Subject(s)
Phantoms, Imaging , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/methods , Brain Neoplasms/surgery , Humans , Models, Theoretical , Radiosurgery/methods , Radiotherapy Planning, Computer-Assisted/standards , Tomography, X-Ray Computed
16.
Int J Radiat Oncol Biol Phys ; 39(3): 757-67, 1997 Oct 01.
Article in English | MEDLINE | ID: mdl-9336160

ABSTRACT

PURPOSE: A two-step procedure is described for accurate planning of stereotactic brain implants prior to head-ring fixation. METHODS AND MATERIALS: Approximately 2 weeks prior to implant a CT scan without the head ring is performed for treatment-planning purposes. An entry point and a reference point, both marked with barium and later tattooed, facilitate planning and permit correlation of the images with a later CT scan. A plan is generated using a conventional treatment-planning system to determine the number and activity of I-125 seeds required and the position of each catheter. I-125 seed anisotropy is taken into account by means of a modification to the treatment planning program. On the day of the implant a second CT scan is performed with the head ring affixed to the skull and with the same points marked as in the previous scan. The planned catheter coordinates are then mapped into the coordinate system of the second CT scan by means of a manual translational correction and a computer-calculated rotational correction derived from the reference point coordinates in the two scans. RESULTS: The rotational correction algorithm was verified experimentally in a Rando phantom before it was used clinically. For analysis of the results with individual patients a third CT scan is performed 1 day following the implant and is used for calculating the final dosimetry. CONCLUSION: The technique that is described has two important advantages: 1) the number and activity of seeds required can be accurately determined in advance; and 2) sufficient time is allowed to derive the best possible plan.


Subject(s)
Brachytherapy/methods , Brain Neoplasms/radiotherapy , Phantoms, Imaging , Radiotherapy Planning, Computer-Assisted/methods , Humans , Radiotherapy Dosage , Tomography, X-Ray Computed
17.
Thromb Haemost ; 68(3): 291-6, 1992 Sep 07.
Article in English | MEDLINE | ID: mdl-1440494

ABSTRACT

The homology between antithrombin III (AT-III) of mouse, of man, and that of other species was investigated. Preliminary experiments showed that mouse AT-III inhibited human alpha-thrombin efficiently (second order rate constant [K2nd] 5.8 x 10(3) M-1 s-1) as compared to human AT-III (K2nd 6.7 x 10(3) M-1), but was not recognized on immunoblots by antibodies that recognized both human and rabbit AT-III. In order to compare AT-III from different species at the molecular level, a cDNA clone for murine AT-III was isolated from a lambda ZAP mouse liver cDNA library on the basis of hybridization to a rabbit AT-III cDNA probe. The 1509 bp murine AT-III cDNA consists of a 1398 bp open reading frame, preceded by a 15 bp 5' untranslated region, followed by a 75 bp 3' untranslated region. The deduced primary protein structure consists of a 32 amino acid signal sequence, with a mature portion of 433 residues. Mature murine AT-III is 89% identical to its human counterpart, 86% identical to bovine AT-III, and 82% identical to that of the rabbit. Constructs lacking the nucleotides encoding the signal sequence were engineered and expressed in a cell-free system. The resulting 47 kDa non-glycosylated translation product was capable of being cleaved by human alpha-thrombin, of forming SDS-stable complexes with the protease, and of binding to immobilized heparin. Isolation of the murine AT-III cDNA will make feasible molecularly defined experiments with murine AT-III in the mouse system.


Subject(s)
Antithrombin III/genetics , DNA/biosynthesis , Amino Acid Sequence , Animals , Antithrombin III/biosynthesis , Antithrombin III/isolation & purification , Base Sequence , Cell-Free System/metabolism , Cloning, Molecular , DNA/analysis , Gene Library , Mice , Mice, Inbred CBA , Mice, Transgenic , Molecular Sequence Data , Plasmids/genetics , Protein Biosynthesis/genetics , Sequence Homology, Amino Acid , Species Specificity , Transcription, Genetic/genetics
18.
FEMS Microbiol Lett ; 179(2): 289-96, 1999 Oct 15.
Article in English | MEDLINE | ID: mdl-10518728

ABSTRACT

IMP-1 metallo-beta-lactamase is a transferable carbapenem-hydrolyzing enzyme found in some clinical isolates of Pseudomonas aeruginosa, Serratia marcescens and Klebsiella pneumoniae. Bacteria that express IMP-1 show significantly reduced sensitivity to carbapenems and other beta-lactam antibiotics. A series of thioester derivatives has been shown to competitively inhibit purified IMP-1. As substrates for IMP-1, the thioesters yielded thiol hydrolysis products which themselves were reversible competitive inhibitors. The thioesters also increased sensitivity to the carbapenem L-742,728 in an IMP-1-producing laboratory stain of Escherichia coli, but will need further modification to improve their activity in less permeable organisms such as Pseudomonas and Serratia. Nonetheless, the thioester IMP-1 inhibitors offer an encouraging start to overcoming metallo-beta-lactamase-mediated resistance in bacteria.


Subject(s)
Bacteria/drug effects , Carbapenems/metabolism , Enzyme Inhibitors/pharmacology , Sulfhydryl Compounds/pharmacology , beta-Lactamase Inhibitors , Bacteria/enzymology
19.
Neurosurgery ; 27(4): 635-7; discussion 637-8, 1990 Oct.
Article in English | MEDLINE | ID: mdl-2234371

ABSTRACT

We report on two patients in whom cervical myelopathy developed decades after they had undergone surgery for congenital cervical cutaneous lesions. Preoperative magnetic resonance imaging demonstrated dorsal tethering and cavitation of the cervical cord in the area of the previous surgery and was helpful in decision making regarding surgical exploration and in planning for it. We stress the importance of long-term follow-up by both clinical examination and magnetic resonance imaging in children who have been operated on for cervical cutaneous masses that may have central connections.


Subject(s)
Meningocele/surgery , Postoperative Complications , Spinal Cord Diseases/etiology , Spinal Nerve Roots/abnormalities , Adult , Cicatrix/complications , Cicatrix/surgery , Humans , Magnetic Resonance Imaging , Male , Neck , Spina Bifida Occulta/etiology , Spina Bifida Occulta/physiopathology , Spina Bifida Occulta/surgery , Spinal Cord Diseases/diagnosis , Spinal Nerve Roots/surgery , Time Factors
20.
Neurosurgery ; 37(4): 704-9; discussion 709-10, 1995 Oct.
Article in English | MEDLINE | ID: mdl-8559299

ABSTRACT

To reach the upper thoracic vertebrae, a number of extensive approaches have been proposed combining thoracotomy, sternotomy, or clavicle resection with anterior dissection into the superior mediastinum. We present a simple anterior cervical approach for patients with disease limited to one vertebral level, in which midline ventral decompression is the goal of surgery. Regardless of the anterior approach used, the caudal extent of exposure is limited to T3 by the great vessels of the mediastinum, whereas the angle of the approach to the cervicothoracic junction is dictated by the manubrium. In the anterior cervical approach, lateral exposure to the uncovertebral joints is easily achieved. Five patients are reviewed in whom this anterior cervical approach was used at the first or second thoracic level. Decompression and instrumentation resulting in neurological improvement and axial stability were achieved in all five patients. The surgical anatomy of the cervicothoracic junction is reviewed with attention to the recurrent laryngeal nerves and the thoracic duct as they relate to the side of approach chosen.


Subject(s)
Cervical Vertebrae/surgery , Spinal Cord Compression/surgery , Spinal Diseases/surgery , Spinal Fusion/methods , Spinal Neoplasms/surgery , Thoracic Vertebrae/surgery , Adult , Aged , Cervical Vertebrae/pathology , Female , Humans , Intervertebral Disc Displacement/diagnosis , Intervertebral Disc Displacement/surgery , Magnetic Resonance Imaging , Male , Middle Aged , Neurologic Examination , Postoperative Complications/diagnosis , Recurrent Laryngeal Nerve Injuries , Risk Factors , Spinal Cord Compression/diagnosis , Spinal Diseases/diagnosis , Spinal Neoplasms/diagnosis , Spinal Neoplasms/secondary , Thoracic Duct/injuries , Thoracic Vertebrae/pathology
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