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Biomedical subjects

K Blum

Publications and source records attributed to K Blum.

At least 19 recordsLinked to original sources

Supraventricular tachyarrhythmias after hematopoietic stem cell transplantation: incidence, risk factors and outcomes.

Recent studies suggest that cancer patients may be at increased risk for supraventricular tachyarrhythmias (SVTA). We have observed clinically significant SVTA in patients undergoing hematopoietic stem cell transplantation occurring at a median of 6 days post transplant, manifesting as atrial fibrillation/flutter or regular narrow-complex tachycardia and persisting for a median of 3 days (range, 0-8). All patients received aggressive medical therapy and/or electrical cardioversion to restore sinus rhythm and to re-establish hemodynamic stability. Non-Hodgkin's lymphoma (NHL) was the most common diagnosis (53%), and a case control analysis in those patients demonstrated that SVTA occurred in 12% of patients and was associated with older age and pre-existing cardiac conditions. In conclusion, patients undergoing HSCT are at moderate risk for developing SVTA, particularly older patients with a diagnosis of NHL. These arrhythmias are clinically significant, and are a marker for increased mortality and prolonged hospital stay. Additional studies are needed to identify high-risk patients who may benefit from prophylactic anti-arrhythmic therapy.

Adult↗

[Proximal row carpectomy: a motion-preserving procedure in the treatment of advanced carpal collapse].

Proximal row carpectomy (PRC) is a motion-sparing procedure for the treatment of advanced carpal collapse. The goal of the operation is the creation of a new joint between the capitate and the radius. The purpose of this retrospective study was the evaluation of the functional outcome after PRC. The evaluation included range of motion, grip strength, and pain reduction. The DASH questionnaire was used to estimate restrictions of the activities of daily living (ADL). Results were ranked with the Mayo and Krimmer wrist scores. Thirty-three patients with a mean age of 41.2 years were evaluated after 36 months. Flexion/extension was 70 degrees and radial and ulnar deviation was 33 degrees. The grip strength was 54% of the unaffected side. The results of Mayo and Krimmer wrist scores were 66 and 69 points. The mean DASH score was 27.8. Eighty-seven percent of the patients reported that pain was better than preoperatively. Resection of the proximal carpal row is technically an easy surgical procedure. It preserves good functional range of motion and provides good pain relief, but low grip strength.

Activities of Daily Living↗

First-trimester trisomy screening: nuchal translucency measurement training and quality assurance to correct and unify technique.

OBJECTIVE: To describe the process of training for measuring nuchal translucency at five clinical centers in North America and to evaluate methods of quality assurance and feedback. DESIGN: Throughout a period of 18 months, the performance of sonographers in measuring fetal nuchal translucency was monitored using qualitative and quantitative methods of review. After 12 months, different approaches (written and personal feedback) were used to inform sonographers of technical aspects that needed to or could be improved. RESULTS: On initial qualitative review, discrepancies in judgment from different reviewers coincided with suboptimal magnification, failure to visualize the amniotic membrane and/or use of cross-shaped calipers. At subsequent global review, 13 (29%) images of nuchal translucency measurements were considered unacceptable. Quantitative assessment revealed that, during the first part of the study, the means from four sonographers were significantly smaller and the mean from the fifth sonographer was significantly larger than expected on the basis of findings from The Fetal Medicine Foundation (P < 0.0001). Following feedback, sonographers who underestimated nuchal translucency and who received a written report only did not change measurements overall (P = 0.9759). In contrast, those who received additional intervention showed a marked difference (P < 0.0001). CONCLUSIONS: Global qualitative review of images from one sonographer may be preferable to assessment of individual aspects of images. Results from global qualitative review correspond well with findings from quantitative analysis, indicating that the latter can be applied for ongoing audit. Observation of divergent results should prompt extensive personal feedback, rather than a written report, to prevent sonographers from settling in their own, inappropriate technique.

Allied Health Personnel↗

Rationale and dose-finding studies of the combination of irinotecan and a taxane on a weekly schedule.

Cisplatin (Platinol)-based chemotherapy has been the standard systemic therapy for both non-small-cell and small-cell lung cancer for the past 2 decades, though the efficacy and benefit remain modest. Recently, several novel agents have been introduced that have single-agent activity comparable to cisplatin and offer the possibility of improved therapy for lung cancer. Camptothecin and taxane derivatives are associated with both different mechanisms of action and nonhematologic toxicities, and have demonstrated additive or synergistic activity when used in combination in preclinical studies. We review pertinent clinical studies of these agents in lung cancer and present our experience in combining irinotecan (Camptosar, CPT-11) with taxanes on a weekly schedule in dose-finding and efficacy studies. When chemotherapy is delivered for 4 consecutive weeks followed by a 2-week rest, hematologic toxicity is dose limiting and most prominent during weeks 3 and 4. Dose intensification is feasible if the schedule is modified so the chemotherapy is given on days 1 and 8, with cycles repeated every 3 weeks. The most common nonhematologic toxicities remain asthenia, neuropathy, and diarrhea. Future studies will explore and better define the role of these drug combinations in the treatment of lung cancer.

Adult↗

Reward deficiency syndrome: genetic aspects of behavioral disorders.

The dopaminergic and opioidergic reward pathways of the brain are critical for survival since they provide the pleasure drives for eating, love and reproduction; these are called 'natural rewards' and involve the release of dopamine in the nucleus accumbens and frontal lobes. However, the same release of dopamine and production of sensations of pleasure can be produced by 'unnatural rewards' such as alcohol, cocaine, methamphetamine, heroin, nicotine, marijuana, and other drugs, and by compulsive activities such as gambling, eating, and sex, and by risk taking behaviors. Since only a minority of individuals become addicted to these compounds or behaviors, it is reasonable to ask what factors distinguish those who do become addicted from those who do not. It has usually been assumed that these behaviors are entirely voluntary and that environmental factors play the major role; however, since all of these behaviors have a significant genetic component, the presence of one or more variant genes presumably act as risk factors for these behaviors. Since the primary neurotransmitter of the reward pathway is dopamine, genes for dopamine synthesis, degradation, receptors, and transporters are reasonable candidates. However, serotonin, norepinephrine, GABA, opioid, and cannabinoid neurons all modify dopamine metabolism and dopamine neurons. We have proposed that defects in various combinations of the genes for these neurotransmitters result in a Reward Deficiency Syndrome (RDS) and that such individuals are at risk for abuse of the unnatural rewards. Because of its importance, the gene for the [figure: see text] dopamine D2 receptor was a major candidate gene. Studies in the past decade have shown that in various subject groups the Taq I A1 allele of the DRD2 gene is associated with alcoholism, drug abuse, smoking, obesity, compulsive gambling, and several personality traits. A range of other dopamine, opioid, cannabinoid, norepinephrine, and related genes have since been added to the list. Like other behavioral disorders, these are polygenically inherited and each gene accounts for only a small per cent of the variance. Techniques such as the Multivariate Analysis of Associations, which simultaneously examine the contribution of multiple genes, hold promise for understanding the genetic make up of polygenic disorders.

Attention Deficit Disorder with Hyperactivity↗

Reward deficiency syndrome: a biogenetic model for the diagnosis and treatment of impulsive, addictive, and compulsive behaviors.

The dopaminergic system, and in particular the dopamine D2 receptor, has been implicated in reward mechanisms. The net effect of neurotransmitter interaction at the mesolimbic brain region induces "reward" when dopamine (DA) is released from the neuron at the nucleus accumbens and interacts with a dopamine D2 receptor. "The reward cascade" involves the release of serotonin, which in turn at the hypothalmus stimulates enkephalin, which in turn inhibits GABA at the substania nigra, which in turn fine tunes the amount of DA released at the nucleus accumbens or "reward site." It is well known that under normal conditions in the reward site DA works to maintain our normal drives. In fact, DA has become to be known as the "pleasure molecule" and/or the "antistress molecule." When DA is released into the synapse, it stimulates a number a DA receptors (D1-D5) which results in increased feelings of well-being and stress reduction. A consensus of the literature suggests that when there is a dysfunction in the brain reward cascade, which could be caused by certain genetic variants (polygenic), especially in the DA system causing a hypodopaminergic trait, the brain of that person requires a DA fix to feel good. This trait leads to multiple drug-seeking behavior. This is so because alcohol, cocaine, heroin, marijuana, nicotine, and glucose all cause activation and neuronal release of brain DA, which could heal the abnormal cravings. Certainly after ten years of study we could say with confidence that carriers of the DAD2 receptor A1 allele have compromised D2 receptors. Therefore lack of D2 receptors causes individuals to have a high risk for multiple addictive, impulsive and compulsive behavioral propensities, such as severe alcoholism, cocaine, heroin, marijuana and nicotine use, glucose bingeing, pathological gambling, sex addiction, ADHD, Tourette's Syndrome, autism, chronic violence, posttraumatic stress disorder, schizoid/avoidant cluster, conduct disorder and antisocial behavior. In order to explain the breakdown of the reward cascade due to both multiple genes and environmental stimuli (pleiotropism) and resultant aberrant behaviors, Blum united this hypodopaminergic trait under the rubric of a reward deficiency syndrome.

Behavior, Addictive↗

Clinical implications of atypical chromosome abnormalities diagnosed prenatally.

OBJECTIVE: To determine the frequency of atypical aneuploidy resulting from prenatal testing and assess the implications of these diagnoses on prenatal decision making. METHODS: We reviewed all amniotic fluid and chorionic villus samples obtained between January 1994 and September 1997 and grouped the abnormal cases into typical or atypical subcategories. This distinction was based upon whether the diagnosis provided a straightforward range of prognoses or an ambiguous clinical implication. Results were stratified by sample source to determine whether atypical aneuploidy was more commonly seen in cultures of chorionic villi or amniocytes. We also evaluated the influence of ultrasound findings on prenatal decision making in atypical aneuploid cases. RESULTS: Of 2960 samples, 134 were abnormal (4.4%), with 27 of 134 abnormalities (20%) representing atypical aneuploidies. The percentages of chorionic villus and amniocentesis cases complicated by atypical aneuploidy (22% and 78%, respectively) were consistent with the distribution of procedures in the entire study. Ultrasound abnormalities did not invariably prompt a decision to terminate pregnancy (only two terminations of six fetuses with congenital malformation), whereas atypical karyotypes led to termination even in the presence of normal-appearing fetal anatomy (five terminations of 21 without malformations; P = .63). CONCLUSION: The frequency of atypical aneuploidy resulting from prenatal diagnosis was approximately 1.0%, and these cases represented 20% of all abnormal karyotypes observed. The ambiguity conferred by atypical aneuploidy can influence a family's decision making, even in the presence of normal ultrasound findings.

Adult↗

Association of polymorphisms of dopamine D2 receptor (DRD2), and dopamine transporter (DAT1) genes with schizoid/avoidant behaviors (SAB).

The dopaminergic system, and in particular the dopamine D2 receptor, has been implicated in reward mechanisms in the brain. Dysfunction of the D2 dopamine receptors leads to aberrant substance-seeking behaviors (ethanol, drugs, tobacco, and food) and other related behaviors (pathological gambling, Tourette's disorder, attention-deficit/hyperactivity disorder). This is the first study supporting a strong association between the dopamine D2 receptor Taq A1 allele with schizoid/avoidant behavior (SAB). Additionally, an albeit weaker association between the 480-bp VNTR 10/10 allele of the dopamine transporter (DAT1) gene with SAB was similarly found.

Adult↗

Enhancement of attention processing by Kantroll in healthy humans: a pilot study.

This is the first report in humans of the effects of daily ingestion of a specific amino acid mixture, Kantroll, on cognitive event-related potentials (ERPs) associated with performance. Cognitive ERPs were generated by two computerized visual attention tasks, the Spatial Orientation Task (SOT) and Contingent Continuous Performance Task (CCPT), in normal young adult volunteers, where each subject acted as his own control for testing before and after 28-30 days of amino acid ingestion. A statistically significant amplitude enhancement of the P300 component of the ERPs was seen after Kantroll for both tasks, as well as improvement with respect to cognitive processing speeds. The enhancement of neurophysiologic function observed in this study on normal controls is consistent with the facilitation of recovery of individuals with RDS (i.e., substance use disorder, ADHD, carbohydrate bingeing) following the ingestion of the amino acid supplement, Kantroll, and warrants additional placebo-controlled, double-blind, studies to confirm and extend these results.

Adult↗

Maternal genetic disease and pregnancy.

This article reviews classic genetic diseases and illustrates the effect of an existing maternal condition on maternal and fetal well-being during pregnancy. The management issues discussed may serve as a framework for treatment when reproductive issues are encountered with other maternal genetic diseases.

Female↗

Increased prevalence of the Taq I A1 allele of the dopamine receptor gene (DRD2) in obesity with comorbid substance use disorder: a preliminary report.

In order to investigate the prevalence of the Taq I A1 allele of the dopamine receptor gene (DRD2) in obesity with and without comorbid substance use disorder, a total of 40 patients, from an outpatient neuropsychiatric clinic in Princeton, New Jersey, were genotyped for presence or absence of the Taq I DRD2 A1 allele. The primary inclusion criterion for 40 obese subjects was a body mass index (BMI) equal to or over 25 (uncharacterized); 11 obese subjects had severe substance use disorder; 20 controls had a BMI below 25; and, 33 substance use disorder (less severe) patients had a BMI below 25. The data were statistically compared with three different sets of controls divided into three separate groups (Group I, n = 20; Group II, n = 286; Group III, n = 714). They differed according to screening criteria (drug, alcohol, nicotine abuse/dependence, BMI below 25 and other related behaviours including parental history of alcoholism or drug abuse and DSM IV, Axis I and Axis II diagnoses). Groups II and III were population controls derived from the literature. The prevalence of the Taq I A1D2 dopamine receptor (DRD2) alleles was determined in 40 Caucasian obese females and males. In this sample with a mean BMI of 32.35 +/- 1.02, the A1 allele of the DRD2 gene was present in 52.5% of these obese subjects. Furthermore, we found that in the 23 obese subjects possessing comorbid substance use disorder, the prevalence of the DRD2 A1 allele significantly increased compared to the 17 obese subjects without comorbid substance use disorder. The DRD2 A1 allele was present in 73.9% of the obese subjects with comorbid substance use disorder compared to 23.5% in obese subjects without comorbid substance use disorder. Moreover, when we assessed severity of substance usage (alcoholism, cocaine dependence, etc.) increasing severity of drug use increased the prevalence of the Taq I DRD2 A1 allele; where 66.67% (8/12) of less severe probands possessed the A1 allele compared to 82% (9/11) of the most severe cases. Linear trend analyses showed that increasing use of drugs was positively and significantly associated with A1 allelic classification (p < 0.00001). These preliminary data suggest that the presence of the DRD2 A1 allele confirms increased risk not only for obesity, but also for other related addictive behaviours (previously referred to as the Reward Deficiency Syndrome) and that a BMI over 25 by itself (without characterization of macroselection or comorbid substance use disorders) is not a sufficient criterion for association with the DRD2 A1 allele.

Adult↗

The D2 dopamine receptor gene as a determinant of reward deficiency syndrome.

The dopaminergic system, and in particular the dopamine D2 receptor, has been profoundly implicated in reward mechanisms in the brain. Dysfunction of the D2 dopamine receptors leads to aberrant substance seeking behaviour (alcohol, drug, tobacco, and food) and other related behaviours (pathological gambling, Tourette's syndrome, and attention deficit hyperactivity disorder). We propose that variants of the D2 dopamine receptor gene are important common genetic determinants of the 'reward deficiency syndrome'.

Compulsive Behavior↗

Substance use disorder exacerbates brain electrophysiological abnormalities in a psychiatrically-ill population.

OBJECTIVE: To assess by brain electrical activity mapping whether cocaine and alcohol abuse and dependence would exacerbate electro-physiological abnormalities in a psychiatrically-ill population. DESIGN, SETTING, AND PARTICIPANTS: Utilizing a brain mapping system, we assessed EEG, Spectral Analysis (Quantitative EEG[QEEG]). Evoked Potentials (Auditory and Visual), and P300 (cognitive evoked potential), in a total of 111 probands divided into three groups: controls (N = 16), psychiatrically-ill without comorbid substance use disorder (N = 34), and psychiatrically-ill with comorbid substance use disorder (cocaine and alcohol abuse and dependence) (N = 61), at an outpatient neuropsychiatric clinic. With regard to demographic data, the group participating in this study did not differ significantly. A comparison was made among the groups to assist in differentiating the effects of substance use disorder compared to psychiatric disease on brain electrical activity. MAIN OUTCOME MEASURES: An assessment of electrophysiological abnormalities and their brain location in psychiatric and substance use disorder patients was done with a brain electrical activity mapping test. MAIN RESULTS: Among the non-substance use disorder, psychiatrically-ill (PI) and substance use disorder, psychiatrically-ill (PI/SD) groups, significantly different brain map abnormalities were observed relative to an assessed normal population MANOVA (P = .017). Moreover, with regard to Spectral Analysis, ANOVA was significant at a P = .038, and we found a weighted linear trend of increased abnormal total spectral analysis (P = .0113), whereby substance use was significantly worse than controls. Moreover among the PI and PI/SD groups, significantly greater total evoked potential (EP) brain trap abnormalities were observed when compared with a characterized normal population (P = .0023) with increasing abnormalities as a function of substance use disorder as measured by a weighted linear trend (P = .0022). In order to determine the site of the EPS abnormalities, we evaluated these abnormalities by location. In this regard, we found all temporal abnormalities (AVBITA, see Table 2) among the PI and PI/SD groups to be significantly greater relative to an assessed normal population (P = .0026). Furthermore, we observed a linear trend of increased temporal abnormalities with increasing substance use disorder (P < .0008). In terms of bitemporal abnormalities (AVBIT) among the PI and PI/SD groups, we also found significantly more bitemporal lobe abnormalities in the PI/SD group compared to our control population (P = .009). Additionally, a weighted linear trend of increased abnormal bitemporal lobe abnormalities was observed with increasing substance use disorder (P = .0022). In the frontal lobe similar findings were observed. With AVBIFA the ANOVA was P < .011, with a weighted linear trend of P < .005 and the PI/SD group were significantly more abnormal than PI or CS on a Duncan Range test. It is noteworthy that in a selected group of depressed (Major Depressive Disorder Recurrent, 296.3) patients, we found profound abnormalities in the various brain map parameters tested. MANOVA and Univariate ANOVA's revealed significantly greater abnormalities in the PI and PI/SD groups compared to assessed controls. A MANOVA for total brain abnormalities was significant at P = .043 and univariate ANOVA's for composite measurements of TSA (P = .017), EPS (P = .0002), AVBITA (P = .000015), and AVBIT (P < .00002) are also significant. With regard to EPS and AVBITA a weighted linear trend was observed where there were increasing abnormalities with increasing substance use disorder, P = .0001 and P = .000003, respectively. Most importantly we found that in addition to increased abnormalities with increasing substance use disorder the PI/SD group had significantly more abnormalities compared to the PI group with regard to both the TSA (P < .05) and AVBIT (P < .05) composite parameters as meas

Alcoholism↗

Lack of association between alcohol-dependence and D3 dopamine receptor gene in three independent samples.

Numerous studies on the involvement of dopamine receptors in the genetics of alcoholism focused on associations between a polymorphism of the D2 dopamine receptor (DRD2) gene and alcohol dependence. However, the results of these studies are conflicting. Another receptor, the D3 dopamine receptor (DRD3), may be of additional interest since it is specifically located in the limbic area, and in particular in the nucleus accumbens which plays a significant role in the reward process of addiction behavior. We thus tested the association in three independent samples of alcoholic patients, with different origins and various inclusion criteria. No difference in the DRD3 gene polymorphism emerged between controls and alcoholic patients, regardless of their origin, inclusion criteria, or presence or absence of the DRD2 TaqI A1-allele. Despite the fact that more information could have been considered and that association studies provide limited information, there is good evidence that this DRD3 polymorphism does not play a major role in the genetic component of alcoholism.

Alcoholism↗

Theiler's virus growth in murine macrophage cell lines depends on the state of differentiation.

Theiler's murine encephalomyelitic virus (TMEV) preferentially replicates in macrophages in the central nervous system of mice during the persistent phase of infection. Macrophages accumulate in demyelinating lesions and are evidently the primary cell to harbor virus. To investigate TMEV-macrophage interactions, we studied GDVII infection of three cell lines, M1, P388D1, and RAW264.7, representing various stages of macrophage differentiation/activation. GDVII virus was bound and internalized by RAW264.7 and P388D1 cells, but not by the precursor cell line M1. While infection of P388D1 cells produced a typical lytic cytopathology with marked loss of cellular activity to 10-20% of the uninfected control cells, RAW264.7 cells showed little cytopathology despite a decrease in cellular activity of 50-60%. Morphologic changes in infected RAW264.7 cells were similar to those occurring after cell activation. Although an infectious center assay showed that all P388D1 and RAW264.7 cells were infected, synthesis of viral RNA and proteins was markedly reduced and virus titers were restricted compared to permissive BHK-21 cells. Infected RAW264.7, but not infected P388D1, cells secreted tumor necrosis factor-alpha and nitric oxide. Therefore, depending on the differentiation and/or activation state, murine macrophages may be resistant to TMEV infection (M1), semipermissive and activated to secrete cytokines (RAW264.7), or semipermissive and not activated to secrete cytokines (P388D1).

Animals↗

Dopamine D2 receptor gene variants: association and linkage studies in impulsive-addictive-compulsive behaviour.

Drug and alcohol seeking behaviour has become a great global problem affecting millions of inhabitants with a cost to society in the billions. Dopaminergic reward pathways have frequently been implicated in the etiology of addictive behaviour. While other neurotransmitters have also been implicated, to date the only molecular genetic defect which has been found to associate with alcoholism, drug dependency, obesity, smoking, pathological gambling, attention-deficit-hyperactivity disorder (ADHD), Tourette syndrome, as well as other related compulsive behaviours, are the variants of the dopamine D2 receptor gene (DRD2). In this review of the available data on the subject, we report a number of independent meta-analyses that confirm an association of DRD2 polymorphisms and impulsive-additive-compulsive behaviour (IACB), which we have termed "Reward Deficiency Syndrome". While we agree that Meta-analyses of all exant studies support an association of variants of DRD2 and IACB, correct negative findings with alcoholism may be due to differences in assessing controls and inclusion/exclusion criteria for selection of diseased probands.

Behavior, Addictive↗