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Publication
Journal: Human Mutation
April/22/2012
Abstract
Pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED) are relatively common skeletal dysplasias resulting in short-limbed dwarfism, joint pain, and stiffness. PSACH and the largest proportion of autosomal dominant MED (AD-MED) results from mutations in cartilage oligomeric matrix protein (COMP); however, AD-MED is genetically heterogenous and can also result from mutations in matrilin-3 (MATN3) and type IX collagen (COL9A1, COL9A2, and COL9A3). In contrast, autosomal recessive MED (rMED) appears to result exclusively from mutations in sulphate transporter solute carrier family 26 (SLC26A2). The diagnosis of PSACH and MED can be difficult for the nonexpert due to various complications and similarities with other related diseases and often mutation analysis is requested to either confirm or exclude the diagnosis. Since 2003, the European Skeletal Dysplasia Network (ESDN) has used an on-line review system to efficiently diagnose cases referred to the network prior to mutation analysis. In this study, we present the molecular findings in 130 patients referred to ESDN, which includes the identification of novel and recurrent mutations in over 100 patients. Furthermore, this study provides the first indication of the relative contribution of each gene and confirms that they account for the majority of PSACH and MED.
Publication
Journal: Genetics in Medicine
November/2/2016
Abstract
OBJECTIVE
Approximately two-thirds of patients with the lysosomal storage disease mucopolysaccharidosis II have progressive cognitive impairment. Intravenous (i.v.) enzyme replacement therapy does not affect cognitive impairment because recombinant iduronate-2-sulfatase (idursulfase) does not penetrate the blood-brain barrier at therapeutic concentrations. We examined the safety of idursulfase formulated for intrathecal administration (idursulfase-IT) via intrathecal drug delivery device (IDDD). A secondary endpoint was change in concentration of glycosaminoglycans in cerebrospinal fluid.
METHODS
Sixteen cognitively impaired males with mucopolysaccharidosis II who were previously treated with weekly i.v. idursulfase 0.5 mg/kg for ≥6 months were enrolled. Patients were randomized to no treatment or 10-mg, 30-mg, or 1-mg idursulfase-IT monthly for 6 months (four patients per group) while continuing i.v. idursulfase weekly.
RESULTS
No serious adverse events related to idursulfase-IT were observed. Surgical revision/removal of the IDDD was required in 6 of 12 patients. Twelve total doses were administrated by lumbar puncture. Mean cerebrospinal fluid glycosaminoglycan concentration was reduced by approximately 90% in the 10-mg and 30-mg groups and approximately 80% in the 1-mg group after 6 months.
CONCLUSIONS
These preliminary data support further development of investigational idursulfase-IT in MPS II patients with the severe phenotype who have progressed only to a mild-to-moderate level of cognitive impairment.Genet Med 18 1, 73-81.
Publication
Journal: European Urology
November/16/2014
Abstract
BACKGROUND
Prostate cancer (PCa) mortality rates are lower in the Mediterranean countries compared with northern Europe. Although specific components of the Mediterranean diet (Med-Diet) may influence PCa risk, few studies have assessed the traditional Med-Diet pattern with the risk of incident advanced or lethal PCa or with disease progression among men diagnosed with nonmetastatic PCa.
OBJECTIVE
To determine whether the traditional Med-Diet pattern is associated with risk of incident advanced or lethal PCa and with PCa-specific and overall mortality among men with PCa.
METHODS
We prospectively followed 47 867 men in the Health Professionals Follow-up Study followed from 1986 to 2010. The case-only analysis included 4538 men diagnosed with nonmetastatic PCa, followed from diagnosis to lethal outcome or to January 2010.
METHODS
We used Cox proportional hazards models to examine traditional and alternative Med-Diet scores in relation to PCa incidence outcomes (advanced and lethal disease). In a case-only survival analysis, we examined postdiagnostic Med-Diet and risk of lethal (metastases or PCa death) and fatal PCa as well as overall mortality among men diagnosed with nonmetastatic disease.
CONCLUSIONS
Between 1986 and 2010, 6220 PCa cases were confirmed. The Med-Diet was not associated with risk of advanced or lethal PCa. In the case-only analysis, there was no association between the Med-Diet after diagnosis and risk of lethal or fatal PCa. However, there was a 22% lower risk of overall mortality (hazard ratio: 0.78; 95% confidence interval, 0.67-0.90; p(trend)=0.0007) among men with greater adherence to the Med-Diet after PCa diagnosis. We found similar associations for the alternative score.
CONCLUSIONS
A higher Med-Diet score was not associated with risk of advanced PCa or disease progression. Greater adherence to the Med-Diet after diagnosis of nonmetastatic PCa was associated with lower overall mortality.
Publication
Journal: Shock
May/22/2008
Abstract
The prognostic value of procalcitonin (PCT) in patients with sepsis at the emergency department (ED) has not been evaluated. We conducted a prospective observational study to compare the prognostic value of PCT on sepsis and compared with a validated score, Mortality in Emergency Department Sepsis (MEDS) score, and C-reactive protein (CRP) in the setting of ED of an urban, university-based medical center. Five hundred twenty-five consecutive adult patients admitted to the ED fulfilling the American College of Clinical Pharmacists/Society of Critical Care Medicine Consensus Conference definition of sepsis were prospectively enrolled. Serum PCT and CRP were evaluated for each patient. Clinical characteristics and laboratory results on ED admission were recorded using a standardized form. Each patient was followed for at least 30 days. The main outcome was early (5-day) and late (6- to 30-day) mortality. The median age of the study sample was 64.0 (interquartile range, 47-76) years old, and the overall 30-day mortality rate was 10.5%. The c-statistic in the prediction of early mortality was 0.89 for MEDS, 0.76 for PCT, and 0.68 for CRP. The c-statistic in the prediction of late mortality was 0.78 for MEDS, 0.70 for PCT, and 0.63 for CRP. Overall, MEDS score has the best discriminative capability among the three tested markers. Under the best cutoff value, PCT was the most sensitive, and MEDS score was the most specific marker. We suggest further combining the information on PCT and MEDS score to enhance the accuracy in predicting ED sepsis mortality.
Publication
Journal: Journal of Virology
November/4/1998
Abstract
TO subgroup strains of Theiler's murine encephalomyelitis virus (TMEV) induce a persistent central nervous system infection and demyelinating disease in mice. This disease serves as an experimental model of multiple sclerosis (MS) because the two diseases have similar inflammatory white matter pathologies and because the immune system appears to mediate demyelination in both processes. We previously reported (H. H. Chen, W. P. Wong, L. Zhang, P. L. Ward, and R. P. Roos, Nat. Med. 1:927-931, 1995) that TO subgroup strains use an alternative initiation codon (in addition to the AUG used to synthesize the picornavirus polyprotein from one long open reading frame) to translate L*, a novel protein that is out of frame with the polyprotein and which plays a key role in the demyelinating disease. We now demonstrate that L* has antiapoptotic activity in macrophage cells and is critical for virus persistence. The antiapoptotic action of L* as well as the differential translation of L* and virion capsid proteins may foster virus persistence in macrophages and interfere with virus clearance. The regulation of apoptotic activity in inflammatory cells may be important in the pathogenesis of TMEV-induced demyelinating disease as well as MS.
Publication
Journal: The American journal of physiology
July/29/1991
Abstract
Eight highly trained cyclists were studied during exercise after glycogen depletion (test A) and during carbohydrate (CHO) loading (test B). In test B subjects were able to complete 2 h of exercise at 70-75% maximal workload (Wmax), whereas the initial intensity of 70% Wmax had to be reduced to 50% in test A. Plasma ammonia increased more rapidly, and plasma alanine, glutamate, and glutamine were lower in test A. Exercise caused a 3.6-fold increase in the proportion of active branched-chain 2-oxoacid dehydrogenase (BC) complex in muscle in test A. No activation occurred in test B. There was an inverse correlation between the activity of the BC complex and the glycogen content of the postexercise biopsies. Exercise did not cause changes in the muscle content of ATP, ADP, AMP, IMP, hypoxanthine, and lactate. It is concluded that CHO loading abolishes increases in branched-chain amino acid (BCAA) oxidation during exercise and that part of the ammonia production during prolonged exercise originates from deamination of amino acids. The data appear to confirm the hypothesis (A.J. M. Wagenmakers, J.H. Coakley, and R.H.T. Edwards. Int. J. Sports Med. 11: S101-S113, 1990) that acceleration of the BCAA aminotransferase reaction may drain the tricarboxylic acid cycle and that glycogen is a carbon chain precursor of tricarboxylic acid cycle intermediates and glutamine.
Publication
Journal: Journal of Sexual Medicine
September/3/2008
Abstract
BACKGROUND
Peyronie's disease (PD) is a fibrotic disorder of the penis whose etiopathophysiology remains unclear. At this time, there is no known reliable nonsurgical treatment. This study reviews our experience with external penile traction therapy to correct the deformity associated with this disorder.
OBJECTIVE
To evaluate prolonged external penile traction as a nonsurgical treatment for PD.
METHODS
Ten men with PD completed this noncontrolled pilot study of traction therapy using the FastSize Penile Extender. Nearly all (90%) had failed prior medical therapy. Traction was applied as the only treatment for 2-8 hours/day for 6 months. All subjects underwent pre- and post-treatment physical examination including measurement of stretched flaccid penile length (SPL) and biothesiometry.
METHODS
Curvature and girth were measured during erection before and after treatment with dynamic duplex ultrasound. Assessment of erectile and sexual function was further assessed with the International Index of Erectile Function and Quality of Life Specific to Male Erection Difficulties (QOL-MED) questionnaires. At 3 and 6 months post-treatment, SPL was measured and subjective assessment of deformity by the patient was recorded.
RESULTS
Subjectively all men noted reduced curvature estimated at 10-40 degrees, increased penile length (1-2.5 cm) and enhanced girth in areas of indentation or narrowing. Objective measures demonstrated reduced curvature in all men from 10-45 degrees; average reduction for the group was 33% (51-34 degrees). SPL increased 0.5-2.0 cm and erect girth increased 0.5-1.0 cm with correction of hinge effect in four out of four men. International Index of Erectile Function-erectile function domain increased from 18.3-23.6 for the group. Changes in quality of life by QOL-MED were not found to be statistically significant in this small series. There were no adverse events including skin changes, ulcerations, hypoesthesia or diminished rigidity.
CONCLUSIONS
Prolonged daily external penile traction therapy is a new approach for the nonsurgical treatment of PD. Further study appears warranted given the response noted in this pilot study.
Publication
Journal: Journal of Neurophysiology
July/23/1986
Abstract
This study tested the hypothesis that functional connection to muscle is necessary for expression of normal motoneuron electrical properties. Also examined was the time course of self-reinnervation. Properties of individual medial gastrocnemius (MG) motor units were examined following section and reanastomosis of the MG nerve. Stages examined were 3-5 wk (prior to reinnervation, no-re), 5-6 wk (low-re), 9-10 wk (med-re), and 9 mo (long-re, preceding paper) after nerve section. Motor units were classified on the basis of their mechanical response as type fast twitch, fast fatiguing (FF), fast twitch with intermediate fatigue resistance (FI), fast twitch, fatigue resistant (FR), or slow twitch, fatigue resistant (S) (11, 24). Motoneuron electrical properties were measured. Muscle fibers were classified using histochemical methods as type fast glycolytic (FG), fast oxidative glycolytic (FOG), or slow oxidative (SO) (60). Prior to functional reinnervation, MG motoneurons exhibited increased input resistance, decreased rheobase, decreased rheobase/input resistance, and decreased axonal conduction velocity. There was no change in mean afterhyperpolarization (AHP) half-decay time. Normal relationships between motoneuron electrical properties were lost. These data are consistent with dedifferentiation of motoneuron properties following axotomy (35, 47). At 5-6 wk after reanastomosis, motor-unit tensions were small, and motoneuron membrane electrical properties were unchanged from the no-re stage. There were no differences in motoneuron electrical properties between cells that elicited muscle contraction and those that did not. Motor-unit types were first recognizable at the med-re stage. The proportions of fast and slow motor units were similar to normal MG. Within the fast units, there were fewer type-FF units and more type-FI and type-FR units than normal, reflecting a general increase in fatigue resistance at this stage. Neither motoneuron membrane electrical properties nor muscle contractile properties had reached normal values, although both were changed in that direction from the low-re stage. Normal relationships between muscle properties, between motoneuron properties, and between motoneuron and muscle properties were re-established. The correspondence between motor-unit type and motoneuron type was similar to normal or 9 mo reinnervated MG. Muscle-unit tetanic tensions became larger with time after reinnervation. Most of the increase in muscle tension beyond the med-re stage could be accounted for by increase in muscle fiber area. There was an increased proportion of SO muscle fibers observed in the med-re muscles, as at the long-re stage.(ABSTRACT TRUNCATED AT 400 WORDS)
Publication
Journal: Brain research. Brain research reviews
October/31/2001
Abstract
Although neuronal cells have long been thought to be the prime target of ischaemic insults, events which occur at the blood-vascular-parenchymal interface are necessary for the initiation of ischaemic tissue injury. This cascade of microvascular events includes fibrin accumulation, endothelium expression of leukocyte adhesion receptors, breakdown of the basal laminae with loss of astrocyte and endothelial cell contacts leading to blood-brain barrier disruption and consequently oedema formation and haemorrhagic transformation. Potential stroke treatments have been studied in the clinic and many have not been particularly successful, probably due to the delicate balance between improved outcome and adverse reactions as well as the window of opportunity for drug treatment after symptom onset. The only acute intervention trial demonstrating any benefit in patients was that of intravenous tissue plasminogen activator (tPA), administered within 3 h of the onset of symptoms of ischaemic stroke. Such treatment improved clinical outcome at 3 months, although there was an increased incidence of symptomatic haemorrhage [New Engl. J. Med. 333 (1995) 1581]. The recent progress made in defining the mechanisms involved in the initiation of ischaemic events, as described in this review, may lead to the identification of new strategies for intervention in the ischaemic cascade.
Publication
Journal: Annals of Surgery
November/14/2011
Abstract
OBJECTIVE
To prospectively evaluate predictive factors of hospital readmission rates in patients undergoing abdominal surgical procedures.
BACKGROUND
Recommendations from MedPAC that the Centers for Medicare and Medicaid Services (CMS) report upon and determine payments based in part on readmission rates have led to an attendant interest by payers, hospital administrators and far-sighted physicians.
METHODS
Analysis of 266 prospective treated patients undergoing major abdominal surgical procedures from September 2009 to September 2010. All patients were prospectively evaluated for underlying comorbidities, number of preop meds, surgical procedure, incision type, complications, presence or absence of primary and/or secondary caregiver, their education level, discharge number of medications, and discharge location. Univariate and multivariate analyses were performed.
RESULTS
Two hundred twenty-six patients were reviewed with 48 (18%) gastric-esophageal, 39(14%) gastrointestinal, 88 (34%) liver, 58 (22%) pancreas, and 33 (12%) other. Seventy-eight (30%) were readmitted for various diagnoses the most common being dehydration (26%). Certain preoperative and intraoperative factors were not found to be significant for readmission being, comorbidities, diagnosis, number of preoperative medications, patient education level, type of operation, blood loss, and complications. Significant predictive factors for readmission were age (≥69 years), number of discharged (DC) meds (≥9 medications), ≤50% oral intake (52% vs. 23%), and DC home with a home health agency (62% vs. 11%)
CONCLUSIONS
Readmission rates for surgeons WILL become a quality indicator of performance. Quality parameters among Home Health agencies are nonexistent, but will reflect on surgeon’s performance. Greater awareness regarding predictors of readmission rates is necessary to demonstrate improved surgical quality.
Publication
Journal: European Journal of Human Genetics
November/9/1998
Abstract
Familial Mediterranean Fever is one of the most frequent recessive disease in non-Ashkenazi Jews. The gene responsible for the disease (MEFV) has very recently been identified. The M694V ('MED') mutation was found in about 80% of the FMF Jewish (Iraqi and North African) chromosomes. To see if the presence of this mutation could be correlated with particular traits of the disease, we examined a number of clinical features in a panel of 109 Jewish FMF patients with 0, 1 or 2 MED mutations. We showed that homozygosity for this mutation was significantly associated with a more severe form of the disease. In homozygous patients, the disease started earlier (mean age 6.4 +/- 5 vs 13.6 +/- 8.9) and both arthritis and pleuritis were twice as frequent as in patients with one or no M694V mutation. Moreover, 3/3 patients with amyloidosis displayed two MED mutations. No association was found with fever, peritonitis, response to colchicine and erysipeloid eruption. The present result strongly suggests the potential prognostic value of the presence of this mutation.
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Publication
Journal: Molecular and Cellular Biology
May/17/1999
Abstract
A synthetic 22-mer peptide (peptide 46) derived from the p53 C-terminal domain can restore the growth suppressor function of mutant p53 proteins in human tumor cells (G. Selivanova et al., Nat. Med. 3:632-638, 1997). Here we demonstrate that peptide 46 binds mutant p53. Peptide 46 binding sites were found within both the core and C-terminal domains of p53. Lys residues within the peptide were critical for both p53 activation and core domain binding. The sequence-specific DNA binding of isolated tumor-derived mutant p53 core domains was restored by a C-terminal polypeptide. Our results indicate that C-terminal peptide binding to the core domain activates p53 through displacement of the negative regulatory C-terminal domain. Furthermore, stabilization of the core domain structure and/or establishment of novel DNA contacts may contribute to the reactivation of mutant p53. These findings should facilitate the design of p53-reactivating drugs for cancer therapy.
Publication
Journal: Journal of Orthopaedic Research
July/19/2004
Abstract
Cartilage oligomeric matrix protein (COMP) is a large extracellular matrix protein expressed in cartilage, ligament and tendon. Mutations in the COMP gene cause two dominantly inherited skeletal dysplasias, pseudoachondroplasia (PSACH) and Multiple Epiphyseal Dysplasia (MED/EDM1). We report on a novel point mutation D511Y in the seventh calcium-binding repeat of the COMP gene and the resulting iliac crest growth plate pathology. The PSACH iliac crest growth plate is comprised of a large region of resting chondrocytes above a narrow region composed of clusters of disorganized proliferative and hypertrophic chondrocytes. Chondrocytes in all zones show massive intracellular retention of COMP and the surrounding extracellular matrix is deficient in COMP. Moreover, the 511Y COMP mutation selectively affects type IX collagen as little is found in the growth plate matrix whereas type II collagen and aggrecan are abundant in the matrix. Chondrocyte remnants are observed in the chondrocyte clusters and dead cells are found throughout the growth plate. Apoptosis studies demonstrate an unusual pattern of TUNEL staining in the PSACH chondrocytes compared to the control growth plate. These in vivo findings support our previous observation that retention of COMP leads to chondrocyte death. These results also add to the increasing evidence that PSACH and EDM1 are rER storage diseases and that impaired linear growth and joint erosion are caused by the disruptive effect of massive amounts of COMP within the chondrocytes.
Publication
Journal: Clinical and Experimental Metastasis
May/11/1998
Abstract
Recent work has shown that chemically modified tetracyclines (CMTs) are potent inhibitors of matrix metalloproteinase (MMP) activity, both in vitro and in vivo, which is distinct from their antimicrobial activities (Golub et al. Crit Rev Oral Biol Med, 2, 297-321, 1991; Ryan et al. Curr Opin Rheumatol, 8, 23847, 1996). The process of tumor cell invasion requires MMP-mediated degradation of extracellular matrix barriers as a key step in the metastasic cascade. In this study, we examined the effect(s) of doxycycline and CMTs on extracellular levels of gelatinase A and B activity from a highly invasive and metastatic human melanoma cell line C8161, and correlated these observations with changes in the cells' biological behavior in an in vitro invasion assay and in an in vivo SCID mouse model. The results indicate that coincident with the ability of these compounds to differentially suppress extracellular levels of gelatinase activity, C8161 cells treated with doxycycline, CMT-1, CMT-3, or CMT-6 were less invasive in vitro in a dose-dependent manner (3-50 microg/ml). Furthermore, data derived from the in vivo model indicate that SCID mice dosed orally with CMT-1 or CMT-3 contained a reduced number of lung metastases following i.v. injection of C8161 cells via tail vein inoculation. These observations suggest that careful screening of different CMTs could lead to the identification of compounds which suppress the formation and magnitude of metastases associated with certain cancers, and if used as an adjunct to other treatment regimes, lead to greater efficacy in the treatment of metastatic cancers.
Publication
Journal: American Journal of Hypertension
June/28/1995
Abstract
The antihypertensive efficacy of six drugs and placebo was compared in 1292 men with untreated diastolic blood pressure of 95 to 109 mm Hg. The primary end point "success" was defined as the patient having achieved a diastolic blood pressure of < 90 mm Hg at the end of the drug titration period and having maintained a diastolic blood pressure of < 95 mm Hg for 1 year without drug intolerance. The original published success rate data (N Engl J Med 1993;328:914-921) were discovered to be in error due to a computer programming code omission (N Engl J Med 1994;330:1689). This paper presents corrected graphic figures. The corrected success rates were generally higher than originally published. Overall, diltiazem (72%) was significantly higher than hydrochlorothiazide (55%), prazosin (54%), captopril (50%), and placebo (31%); clonidine (62%) and atenolol (60%) were intermediate. There were some changes in the hierarchy of drug response, but important differences in success rates according to age by race subgroups remained. Whites responded well to all drug classes, except for lower efficacy of hydrochlorothiazide in younger whites. Blacks responded better to diltiazem than other agents. In addition, we have analyzed the data using a definition of success based on < 90 mm Hg for 1 year. Use of the <90 mm Hg criterion reduced the rate of success, but had only a minor effect on the drug success rate hierarchy. We conclude that single-drug antihypertensive therapy is effective in a majority of stage 1 to 2 diastolic hypertensive patients, although there are important age-by-race differences in success rates among various drug classes.
Publication
Journal: Magnetic Resonance in Medicine
September/12/2001
Abstract
The influence of anesthetic agents on cerebral blood flow (CBF) was tested in normal rats. CBF is quantified with arterial spin-labeled MRI in rats anesthetized with either an opiate (fentanyl), a potent inhalation anesthetic agent (isoflurane), or a barbiturate (pentobarbital) using doses commonly employed in experimental paradigms. CBF values were found to be about 2.5-3 times lower in most regions analyzed during anesthesia with either fentanyl (with N(2)O/O(2)) or pentobarbital vs. isoflurane (with N(2)O/O(2)), in agreement with findings utilizing invasive measurement techniques. CBF was heterogeneous in rats anesthetized with isoflurane (with N(2)O/O(2)), but relatively homogeneous in rats anesthetized with either fentanyl (with N(2)O/O(2)) or pentobarbital, also in agreement with studies using other techniques. Magn Reson Med 46:202-206, 2001.
Publication
Journal: BMJ Open
December/31/2012
Abstract
BACKGROUND
Acute lung injury (ALI) is a devastating condition that places a heavy burden on public health resources. Although the need for effective ALI prevention strategies is increasingly recognised, no effective preventative strategies exist. The Lung Injury Prevention Study with Aspirin (LIPS-A) aims to test whether aspirin (ASA) could prevent and/or mitigate the development of ALI.
METHODS
LIPS-A is a multicentre, double-blind, randomised clinical trial testing the hypothesis that the early administration of ASA will result in a reduced incidence of ALI in adult patients at high risk. This investigation will enrol 400 study participants from 14 hospitals across the USA. Conditional logistic regression will be used to test the primary hypothesis that early ASA administration will decrease the incidence of ALI.
BACKGROUND
Safety oversight will be under the direction of an independent Data and Safety Monitoring Board (DSMB). Approval of the protocol was obtained from the DSMB prior to enrolling the first study participant. Approval of both the protocol and informed consent documents were also obtained from the institutional review board of each participating institution prior to enrolling study participants at the respective site. In addition to providing important clinical and mechanistic information, this investigation will inform the scientific merit and feasibility of a phase III trial on ASA as an ALI prevention agent. The findings of this investigation, as well as associated ancillary studies, will be disseminated in the form of oral and abstract presentations at major national and international medical specialty meetings. The primary objective and other significant findings will also be presented in manuscript form. All final, published manuscripts resulting from this protocol will be submitted to Pub Med Central in accordance with the National Institute of Health Public Access Policy.
Publication
Journal: Cancer Research
September/18/1984
Abstract
A new stochastic numerical model of breast cancer growth is developed. First, the model suggests that Gompertzian kinetics does apply but that from time to time, in random fashion, there occurs a spontaneous change in the growth rate or rate of decay of growth, such that the overall growth pattern occurs in a stepwise fashion. According to the model, the average time for the tumor burden to increase from one cell to detection is probably in the range of 8 years. Secondly, the model suggests that there is a linear relationship between the number of axillary lymph nodes positive for metastasis at diagnosis and the number of other metastatic sites. This can be described mathematically by the equation S = 0.24 + 0.35N where S is the number of other metastatic sites and N is the number of positive lymph nodes. The model has been verified by simulating three data sets: (a) the survival times of untreated breast cancer patients as described by Bloom et al. [Br. Med. J., 2: 213-221, 1962]; (b) the growth rates of breast cancers immediately prior to diagnosis as described by Heuser and Spratt [Cancer (Phila.), 43: 1888-1894, 1979]; and (c) the disease-free survival time postmastectomy as described by Fisher et al. [Surg. Gynecol. Obstet., 140: 528-534, 1975]. This model could have implications concerning the overall treatment rationale for breast cancer.
Publication
Journal: Journal of Medicinal Chemistry
February/15/1993
Abstract
The specificity of interactions between biological macromolecules and their ligands may be partially attributed to the directional properties of hydrogen bonds. We have now extended the GRID method (Goodford, P. J. J. Med. Chem. 1985, 28, 849. Boobbyer, D. N. A.; Goodford, P. J.; McWhinnie, P. M.; Wade, R. C. J. Med. Chem. 1989, 32, 1083), of determining energetically favorable ligand binding sites on molecules of known structure, in order to improve the treatment of groups which can make multiple hydrogen bonds. In this method, the interaction energy between a probe (a small chemical group that may be part of a larger ligand) and a target molecule is calculated using an energy function which includes a hydrogen bond term which is dependent on the length of the hydrogen bond, its orientation at the hydrogen-bonding atoms, and their chemical character. The methods described in the preceding paper (Wade, R. C.; Clark, K. J.; Goodford, P. J. J. Med. Chem., preceding paper in this issue) for probes capable of making two hydrogen bonds are here extended to the following probes which have the ability to make more than two hydrogen bonds: ammonium-NH3+, amine-NH2, sp3-hybridized hydroxyl, and water. Use of the improved GRID procedure is demonstrated by the determination of the conformation of an amino acid side chain at the subunit interface in hemoglobin and of the location of water binding sites in human lysozyme.
Publication
Journal: IEEE Transactions on Image Processing
October/1/2012
Abstract
This paper reviews and compares three maximum likelihood algorithms for transmission tomography. One of these algorithms is the EM algorithm, one is based on a convexity argument devised by De Pierro (see IEEE Trans. Med. Imaging, vol.12, p.328-333, 1993) in the context of emission tomography, and one is an ad hoc gradient algorithm. The algorithms enjoy desirable local and global convergence properties and combine gracefully with Bayesian smoothing priors. Preliminary numerical testing of the algorithms on simulated data suggest that the convex algorithm and the ad hoc gradient algorithm are computationally superior to the EM algorithm. This superiority stems from the larger number of exponentiations required by the EM algorithm. The convex and gradient algorithms are well adapted to parallel computing.
Publication
Journal: Infection and Immunity
October/20/1980
Abstract
A lectin (carbohydrate-binding protein) has been found in extracts of a number of axenically grown trophozoites of Entamoeba histolytica strains. The strains grown in TYI-S-33 medium (Diamond et al., Trans. R. Soc. Trop. Med. Hyg. 72: 431-432, 1978) were HK-9, 200:NIH, and HM-1:IMSS. Strain HU-1:MUSC (HSC) was grown monoxenically in the same medium. The amoebic lectin agglutinated glutaraldehyde-fixed erythrocytes. This activity was pH dependent and heat and oxidation sensitive, and was destroyed by proteolysis upon autoincubation. The relative agglutinating potency of the different strains of amoebae was investigated. Strain HSC had the highest specific activity (210 U/mg of protein), and strain HM-1 had the lowest (14 U/mg). One unit of hemagglutinating activity is defined as the amount of lectin present in 1 ml of extract which will agglutinate 1 ml of 4% erythrocytes. Upon subcellular fractionation of the lectin present in extracts of strain HK-9, two-thirds of the activity was detected in the soluble, nonsedimentable (100,000 x g, 60 min) fraction. Partial hydrolysate of chitin was found to inhibit the hemagglutinating activity. Among the oligosaccharides of N-acetylglucosamine, the trimer and tetramer were the most potent inhibitors. The lectin was purified approximately 300-fold by a one-step affinity chromatography on a chitin column. The loading and elution from the column were based on the pH dependence of the lectin activity.
Publication
Journal: Intensive Care Medicine
August/26/2007
Abstract
OBJECTIVE
Recent studies have shown significant cognitive problems some months after critical illness. However there has been no research examining cognitive function within the intensive care unit (ICU) in non-delirious patients.
METHODS
A prospective study in an ICU.
METHODS
Using the Cambridge Neuropsychological Test Automated Battery (CANTAB), 30 long-stay, tracheal-intubated ICU patients were tested. Prior to testing on ICU the Confusion Assessment Measure (CAM-ICU) was administered and only those patients clearly not delirious and off sedation for several days were tested. The CANTAB tests were repeated a week after ICU discharge on the general ward and then again at 2 months. Sixteen patients completed the follow-up.
RESULTS
While on ICU all 30 patients showed significant problems with strategic thinking and problem solving; 20 patients had some problems with memory. The degree of difficulty with problem solving on ICU was correlated with length of ICU stay (p=0.011), age (p=0.036) and length of hospital stay post ICU (p=0.044). Problems with memory in ICU and on the general ward were correlated with admission APACHE II score (p=0.004 and p=0.005 respectively). At the 2-month follow-up 5 of 16 patients (31%) scored below the 25 percentile for memory and 8 of 16 (50%) below the 25 percentile for problem solving (Slater TA, Jones C, Griffiths RD, Wilson S, Benjamin K (2004) Cognitive impairment during and after intensive care: a pilot study. Intensive Care Med 30 [Suppl 1]:S199).
CONCLUSIONS
Difficulties with problem solving and poor memory remained a significant issue for 2 months after ICU discharge.
Publication
Journal: American journal of medical genetics
February/23/2000
Abstract
Obsessive-compulsive disorder (OCD) is a complex psychiatric disorder characterized by recurring obsessions or compulsions that cause significant distress to the patient or significantly interfere with the patient's normal home, work, or social activities [Diagnostic and Statistical Manual of Mental Disorders, 4th Edition. Washington, DC: American Psychiatric Association, 1994]. Twin and family studies have suggested that OCD has a significant genetic component. We performed complex segregation analyses using POINTER with families ascertained through an OCD-affected proband. In an attempt to resolve the phenotypic heterogeneity observed among individuals with OCD these segregation analyses used four factor-analytic symptom dimensions to subset the family sample based upon probands' symptom factor scores. Analysis of the entire sample allowed rejection of only the no transmission model; that model was also rejected in all subsequent analyses. Limiting the analyses to families with at least one OCD-affected member in addition to the proband (the demonstrably familial form of OCD) allowed rejection of all models except the mixed model. Analyses limited to families of high-factor-3 (symmetry and ordering symptoms) probands led to rejection of the polygenic model, indicating the involvement of a major locus. Additionally, the relative risk of OCD or subclinical OCD was 1.7 for relatives of probands with a factor 3 score greater than zero compared with relatives of probands with a low factor score. The symptoms attributed to high factor 3 scores (symmetry and ordering) may constitute a genetically significant symptomatic subtype of OCD. Am. J. Med. Genet. (Neuropsychiatr. Genet.) 88:669-675, 1999.
Publication
Journal: Medical Physics
January/24/2001
Abstract
Subsecond spiral computed tomography (CT) offers great potential for improving heart imaging. The new multi-row detector technology adds significantly to this potential. We therefore developed and validated dedicated cardiac reconstruction algorithms for imaging the heart with subsecond multi-slice spiral CT utilizing electrocardiogram (ECG) information. The single-slice cardiac z-interpolation algorithms 180 degrees CI and 180 degrees CD [Med. Phys. 25, 2417-2431 (1998)] were generalized to allow imaging of the heart for M-slice scanners. Two classes of algorithms were investigated: 180 degrees MCD (multi-slice cardio delta), a partial scan reconstruction of 180 degrees + delta data with a < phi (fan angle) resulting in effective scan times of 250 ms (central ray) when a 0.5 s rotation mode is available, and 180 degrees MCI (multi-slice cardio interpolation), a piecewise weighted interpolation between successive spiral data segments belonging to the same heart phase, potentially providing a relative temporal resolution of 12.5% of the heart cycle when a four-slice scanner is used and the table increment is chosen to be greater than or equal to the collimated slice thickness. Data segments are selected by correlation with the simultaneously recorded ECG signal. Theoretical studies, computer simulations, as well as patient measurements were carried out for a multi-slice scanner providing M = 4 slices to evaluate these new approaches and determine the optimal scan protocol. Both algorithms, 180 degrees MCD and 180 degrees MCI, provide significant improvements in image quality, including extremely arythmic cases. Artifacts in the reconstructed images as well as in 3D displays such as multiplanar reformations were largely reduced as compared to the standard z-interpolation algorithm 180 degrees MLI (multi-slice linear interpolation). Image quality appears adequate for precise calcium scoring and CT angiography of the coronary arteries with conventional subsecond multislice spiral CT. It turned out that for heart rates fH>> or = 70 min(-1) the partial scan approach 180 degrees MCD yields unsatisfactory results as compared to 180 degrees MCI. Our theoretical considerations show that a freely selectable scanner rotation time chosen as a function of the patient's heart rate, would further improve the relative temporal resolution and thus further reduce motion artifacts. In our case an additional 0.6 s mode besides the available 0.5 s mode would be very helpful. Moreover, if technically feasible, lower rotation times such as 0.3 s or even less would result in improved image quality. The use of multi-slice techniques for cardiac CT together with the new z-interpolation methods improves the quality of heart imaging significantly. The high temporal resolution of 180 degrees MCI is adequate for spatial and temporal tracking of anatomic structures of the heart (4D reconstruction).
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