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1.
Med Klin Intensivmed Notfmed ; 115(4): 312-319, 2020 May.
Article in German | MEDLINE | ID: mdl-31363797

ABSTRACT

INTRODUCTION: Cancer is one of the leading causes of death worldwide. Due to increasing comorbidities, age and aggressive chemotherapy, care of cancer patients in intensive care units (ICUs) is more and more necessary. So far, little is known about the care structure of cancer patients in German ICUs. The aim of this work is to collect and evaluate the prevalence and care data of cancer patients on two reference dates. METHODS: German ICUs were invited to participate in a 2-day, prospective, multicenter point prevalence study in ICU cancer patients. Participation in the study was voluntary and the study was not funded. An ethics vote was obtained to conduct the study. The data were anonymously entered into an eCRF (electronic case report form) by the participating centers. Identification of the patients is therefore not possible. RESULTS: About one in four patients on the ICU/IMC ward had hematological-oncological (HO) disease (n = 316/1319, 24%). The proportion depended significantly on the number of beds in each hospital. The most frequent reasons for admission to the ICU/IMC station were postoperative monitoring (n = 83/221, 37.6%), respiratory instability (n = 79/221, 35.7%), circulatory instability (n = 52/221; 23.5%) and the severe infection with sepsis (n = 47/221; 21.3%). In all, 66.5% (n = 147/221) of the patients had a solid tumor and 21.7% (n = 48/221) had hematological cancer, 78.3% (n = 173/221) of the documented cancer patients received "full-code" intensive management, while 42.5% (n = 94/221) of the HO patients were ventilated and 40.7% (n = 90/221) required catecholamines. The median (mean; IQR) SAPS II score was 35 (37.79, IQR = 24-48) and the median (mean, IQR) TISS score was 10 (13.26, IQR = 10-15). Through the analysis and evaluation of the data available in the context of the prevalence study, it was possible for the first time to determine the Germany-wide cross-center prevalence and care situation of hematological cancer patients in intensive care and intermediate care stations. About one in four patients on German ICUs and IMC wards have a major or minor cancer diagnosis (n = 316/1319 = 24%). Care management is complex in this patient population and requires close interdisciplinary collaboration.


Subject(s)
Intensive Care Units , Sepsis , Germany , Humans , Prevalence , Prospective Studies
2.
Hum Immunol ; 80(4): 257-262, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30790598

ABSTRACT

INTRODUCTION: Chromosomal abnormalities are frequent events in hematological malignancies. The degree of HLA compatibility between donor and recipient in hematopoietic stem cell transplantation is critical. PURPOSE OF THE STUDY: In this report, we describe an acute myeloid leukemia case with loss of heterozygosity (LOH) encompassing the entire HLA. MATERIALS AND METHODS: HLA molecular typing was performed on peripheral blood (PB) and buccal swabs (BS). Chromosomal microarray analysis (CMA) was performed using a whole genome platform. RESULTS: Typing results on PB sample collected during blast crisis demonstrated homozygosity at the -A, -B, -C, -DR, and -DQ loci. A BS sample demonstrated heterozygosity at all loci. A subsequent PB sample drawn after count recovery confirmed heterozygosity. The CMA performed on PB samples collected during and after blast crisis revealed a large terminal region of copy-neutral LOH involving chromosome region 6p25.3p21.31, spanning approximately 35.9 Mb. The results of the CMA assay on sample collected after count recovery did not demonstrate LOH. CONCLUSIONS: LOH at the HLA gene locus may significantly influence the donor search resulting in mistakenly choosing homozygous donors. We recommend confirming the HLA typing of recipients with hematological malignancies when homozygosity is detected at any locus by using BS samples, or alternatively from PB when remission is achieved.


Subject(s)
Bone Marrow/physiology , Genome/genetics , Hematopoietic Stem Cell Transplantation , Leukemia, Myeloid, Acute/genetics , Leukocytes, Mononuclear/physiology , Loss of Heterozygosity , Major Histocompatibility Complex/genetics , Aged , Blood Circulation , Female , Histocompatibility Testing , Humans , Leukemia, Myeloid, Acute/diagnosis , Leukemia, Myeloid, Acute/therapy , Microarray Analysis , Molecular Diagnostic Techniques , Remission Induction
3.
Nanoscale ; 8(7): 4134-44, 2016 Feb 21.
Article in English | MEDLINE | ID: mdl-26866469

ABSTRACT

There continues to be a significant increase in the number and complexity of hydrophobic nanomaterials that are engineered for a variety of commercial purposes making human exposure a significant health concern. This study uses a combination of biophysical, biochemical and computational methods to probe potential mechanisms for uptake of C60 nanoparticles into various compartments of living immune cells. Cultures of RAW 264.7 immortalized murine macrophage were used as a canonical model of immune-competent cells that are likely to provide the first line of defense following inhalation. Modes of entry studied were endocytosis/pinocytosis and passive permeation of cellular membranes. The evidence suggests marginal uptake of C60 clusters is achieved through endocytosis/pinocytosis, and that passive diffusion into membranes provides a significant source of biologically-available nanomaterial. Computational modeling of both a single molecule and a small cluster of fullerenes predicts that low concentrations of fullerenes enter the membrane individually and produce limited perturbation; however, at higher concentrations the clusters in the membrane causes deformation of the membrane. These findings are bolstered by nuclear magnetic resonance (NMR) of model membranes that reveal deformation of the cell membrane upon exposure to high concentrations of fullerenes. The atomistic and NMR models fail to explain escape of the particle out of biological membranes, but are limited to idealized systems that do not completely recapitulate the complexity of cell membranes. The surprising contribution of passive modes of cellular entry provides new avenues for toxicological research that go beyond the pharmacological inhibition of bulk transport systems such as pinocytosis.


Subject(s)
Cell Membrane/metabolism , Fullerenes/metabolism , Animals , Cell Membrane/chemistry , Endocytosis , Fullerenes/chemistry , Macrophages/cytology , Macrophages/metabolism , Magnetic Resonance Spectroscopy , Mice , Microscopy, Electron, Transmission , Molecular Dynamics Simulation , Nanostructures/chemistry , RAW 264.7 Cells , Terbium/chemistry
4.
Cultur Divers Ethnic Minor Psychol ; 21(2): 288-99, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25150818

ABSTRACT

The purpose of the research was to determine whether European American and Latino mock jurors would demonstrate bias in death penalty decision making when mitigation evidence and defendant ethnicity and socioeconomic status (SES) were varied. A total of 561 actual venire persons acted as mock jurors and read a trial transcript that varied a defendant's case information (mitigating circumstances: strong/weak, defendant ethnicity: European American/Latino, and defendant SES: low/high). European American jurors recommended the death penalty significantly more often for the low SES Latino defendant when strength of mitigation evidence was weak. In addition, they also assigned this defendant higher culpability ratings and lower ratings on positive personality trait measures compared with all other conditions. Strong mitigation evidence contributed to lower guilt ratings by European American jurors for the high SES European American defendant. Latino jurors did not differ in their death penalty sentencing across defendant mitigation, ethnicity, or SES conditions. Discussion of in-group favoritism and out-group derogation, as well as suggestions for procedures to diminish juror bias in death penalty cases, is provided.


Subject(s)
Capital Punishment/legislation & jurisprudence , Hispanic or Latino/legislation & jurisprudence , White People/legislation & jurisprudence , White People/psychology , Adult , Bias , California , Crime/ethnology , Crime/legislation & jurisprudence , Decision Making , Female , Humans , Judicial Role , Jurisprudence , Lawyers/legislation & jurisprudence , Male , Prejudice/psychology , Social Class , Stereotyping
5.
Cultur Divers Ethnic Minor Psychol ; 14(4): 364-71, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18954172

ABSTRACT

Racial bias in legal decision making has been given considerable attention over the past few decades, focusing mainly on African Americans to the exclusion of other minority groups. The purpose of this study was to address the dearth of research examining bias against Mexican American defendants. Two hundred forty-seven participants read through a trial transcript that varied defendant race/ethnicity (Mexican American or European American), defense attorney race/ethnicity (Mexican American or European American), and defendant socioeconomic status (SES; low or high [upper middle class]). Dependent measures included verdict, sentencing, culpability ratings, and trait assessments. Bias against Mexican American defendants occurred most when the Mexican American defendant was of low SES and represented by a Mexican American defense attorney. In addition, attorneys representing low-SES Mexican American defendants were perceived as less competent and rated lower on a number of trait measures. Limitations, applications, and future directions are discussed.


Subject(s)
Decision Making, Organizational , Lawyers/legislation & jurisprudence , Mexican Americans , Personality , Prejudice , Social Perception , Adult , Female , Humans , Jurisprudence , Male , Surveys and Questionnaires
6.
Int J Artif Organs ; 24(7): 434-42, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11510914

ABSTRACT

To investigate the role of extracorporeal detoxification in cirrhotic patients with advanced hepatic encephalopathy not responding to medical treatment, 20 patients were randomized to receive six hours of additional sorbent dialysis or ongoing standardized medical treatment. Following treatment, the clinical stage of encephalopathy remained unchanged in both groups. Abnormal sensory evoked potentials improved following sorbent dialysis (N70 latency, 128 ms before versus 110 ms after treatment, P<0,05; cervico-cranial transmission, 7.7 ms versus 6.8 ms, P<0.01) indicating improvement in important aspects of cerebral function. In contrast, brain function remained unchanged following medical treatment (N70 latency, 114 ms versus 113 ms; cervico-cranial transmission, 7.7 ms versus 7.2 ms, P=NS, respectively). Serum benzodiazepine levels decreased significantly after sorbent dialysis but not after medical treatment. Biocompatibility of sorbent dialysis was limited and clinical complications occurred in a proportion of patients. In conclusion, a six-hour treatment with sorbent suspension dialysis did not ameliorate the clinical stage of HE but improved neurophysiologic function in cirrhotic patients who had not responded to conventional medical treatment.


Subject(s)
Dialysis Solutions/therapeutic use , Hepatic Encephalopathy/therapy , Renal Dialysis/methods , Adult , Aged , Brain/metabolism , Brain/physiopathology , Chronic Disease , Electroencephalography , Evoked Potentials, Somatosensory , Female , Hepatic Encephalopathy/blood , Hepatic Encephalopathy/etiology , Hepatic Encephalopathy/physiopathology , Humans , Liver Cirrhosis/complications , Liver Cirrhosis/therapy , Male , Middle Aged , Renal Dialysis/adverse effects , Treatment Outcome
7.
Vaccine ; 17(7-8): 904-14, 1999 Feb 26.
Article in English | MEDLINE | ID: mdl-10067697

ABSTRACT

This phase I clinical trial was designed to determine the feasibility of using rBCG as a live bacterial vaccine vector for the outer surface protein A (OspA) of Borrelia burgdorferi and as model for other vaccines based on a rBCG vector. To construct the vaccine, a signal peptide derived from a mycobacterial lipoprotein was used to direct the export, and membrane-associated surface expression, of OspA in a standard strain of BCG (Connaught). The rBCG OspA vaccine was safe and immunogenic in several animal species, and protective in a mouse model of Lyme borreliosis. An intradermal injection (0.1 ml) of rBCG OspA was administered to 24 healthy adult volunteers sequentially at one of four dose levels, ranging from 2.0 x 10(4) CFU to 2 x 10(7) CFU, using a dose-escalation design. All volunteers were initially PPD-skin test and OspA antibody negative, and they were monitored for 2 years after immunization. Three volunteers had mild flu-like reactions 1-2 days after vaccination. Local ulceration and drainage at the site of injection, which occurred in 50% and 83% of volunteers in the two highest dose groups, persisted for 1-70 days before the ulcers healed. Most of the drainage samples yielded rBCG colonies that contained the OspA plasmid. Thirteen of 24 vaccinees, principally in the two highest dose groups, converted their PPD skin tests from negative to positive. None of the 24 volunteers developed OspA antibody. In conclusion, the current rBCG vaccine construct, the first such construct tested in humans, had a safety profile comparable to that of licensed BCG, but it did not elicit primary humoral responses to the vectored antigen.


Subject(s)
Antigens, Surface/adverse effects , Antigens, Surface/immunology , BCG Vaccine/adverse effects , BCG Vaccine/immunology , Bacterial Outer Membrane Proteins/adverse effects , Bacterial Outer Membrane Proteins/immunology , Borrelia burgdorferi Group/immunology , Lipoproteins , Lyme Disease/prevention & control , Vaccines, Synthetic/adverse effects , Vaccines, Synthetic/immunology , Adolescent , Adult , Animals , Antigens, Surface/genetics , BCG Vaccine/genetics , Bacterial Outer Membrane Proteins/genetics , Bacterial Vaccines , Borrelia burgdorferi Group/growth & development , Enzyme-Linked Immunosorbent Assay , Female , Humans , Male , Mice , Tuberculin Test , Vaccines, Synthetic/genetics
8.
Sex Transm Dis ; 25(5): 243-50, 1998 May.
Article in English | MEDLINE | ID: mdl-9587175

ABSTRACT

BACKGROUND AND OBJECTIVES: Human papillomavirus (HPV) is strongly implicated in the etiology of cervical neoplasia; however, the frequency, rate, and predictors of neoplastic progression are unknown. GOAL: To measure the type-specific prevalence of cervical HPV and the rate of development of cytological abnormalities among a cohort of college women and to elucidate factors associated with acquisition of HPV DNA and progression to cytological abnormalities. STUDY DESIGN: Women 18 to 40 years of age seeking routine gynecologic care at a university health center were enrolled in a cross-sectional study with prospective, longitudinal follow-up of a subset of women. Demographic and behavioral data were collected using a written questionnaire. HPV DNA was detected in cervical scrapes by polymerase chain reaction using L1 consensus primers and a generic and 25 type-specific probes, and cervical cytological abnormalities were identified by Papanicolaou's (Pap) smear. RESULTS: HPV DNA was detected in 35% of the 414 women in the cross-sectional study; 66% of infections were with intermediate or high cancer risk HPV types. Multiple lifetime sex partners was an independent predictor of prevalent infection. Longitudinal analysis of 205 women showed that detection was transient (HPV DNA absent at follow-up) in 38% of the 84 women who were HPV-positive at enrollment. Persistent detection of the same HPV type at > or = 2 visits occurred in 14% of women and was significantly more common when intermediate or high cancer risk types were present. After 16 months of observation, 9% of HPV-infected women developed low-grade squamous intraepithelial lesions (SIL) and 5% developed high-grade SIL; the risk of incident SIL was 7.8-fold higher among women who had persistent HPV detection with the same type. CONCLUSIONS: It was concluded that cervical HPV infection is highly prevalent among college women. Although most infections are caused by intermediate of high cancer risk types, few women (5%) developed high-grade SIL during 16 months of observation.


Subject(s)
Genital Diseases, Female/epidemiology , Papillomaviridae , Papillomavirus Infections/epidemiology , Tumor Virus Infections/epidemiology , Adolescent , Adult , DNA, Viral/analysis , Female , Genital Diseases, Female/etiology , Humans , Longitudinal Studies , Papanicolaou Test , Papillomavirus Infections/etiology , Prevalence , Risk Factors , Tumor Virus Infections/etiology , Vaginal Smears
10.
Theriogenology ; 49(5): 917-32, 1998 Apr 01.
Article in English | MEDLINE | ID: mdl-10732100

ABSTRACT

This study was designed to develop preantral follicle isolation and classification protocols for the domestic dog as a model for endangered canids. Ovary donors were grouped by age, size, breed purity, ovary weight and ovary status. Ovaries were randomly assigned to 1 of 3 digestion protocols: A) digestion and follicle isolation on the day of spaying; B) storage at 4 degrees C for 18 to 24 h prior to digestion and follicle isolation; C) digestion on the day of spaying, then incubation at 4 degrees C for 18 h prior to follicle isolation. Minced tissue was placed in a collagenase/DNase solution at 37 degrees C for 1 h. Follicles were classified by oocyte size and opaqueness and by size and appearance of the granulosa cell layers. Preantral follicles contained small, pale oocytes. Preantral follicles containing grown oocytes with dense cytoplasmic lipid were designated as advanced preantral. Only advanced preantral and early antral follicles were examined and classified further. Group 1 follicles had incomplete or absent granulosa layers, Group 2 follicles had several intact granulosa layers, while Group 3 were vesicular (early antral) follicles. Misshapen or pale grown oocytes were classified as degenerated. The percentage of intact germinal vesicles (GV) was recorded for each Group. Digestion Protocol B produced the lowest percentage of degenerated follicles (P < 0.01). Prepubertal donors had fewer (P < 0.01) follicles in each Group and more (P < 0.001) degenerated follicles than older bitches. Larger ovaries yielded the highest total number of follicles (P < 0.05). Ovary status did not affect follicle yield. Oocytes from Group 1 follicles had fewer intact GVs than those from Group 2 or Group 3 (P < 0.0001). These findings provide an opportunity for quantitative studies of the factors regulating folliculogenesis in the domestic dog as a model for endangered canids.


Subject(s)
Estrus/physiology , Ovarian Follicle/cytology , Ovarian Follicle/physiology , Animals , Carnivora , Cell Separation , Conservation of Natural Resources , Dogs , Female , Granulosa Cells/cytology , Hysterectomy , Models, Biological , Ovariectomy , Ovary/cytology , Ovary/physiology
11.
Theriogenology ; 49(5): 933-42, 1998 Apr 01.
Article in English | MEDLINE | ID: mdl-10732101

ABSTRACT

Initial studies in our laboratory demonstrated that a large proportion of domestic dog advanced preantral (APAN) and early antral (EAN) follicles contained grown oocytes that had acquired the dense cytoplasmic lipid characteristic of preovulatory oocytes. The objective of this study was to assess nuclear maturation of those oocytes after in vitro culture. Both APAN and EAN follicles (152 to 886 microns in diameter) were isolated from ovaries by treatment with collagenase and DNase. The follicles were cultured in Dulbecco's Modified Eagle's medium/nutrient mixture F-12 Ham culture medium supplemented with 20% (v/v) fetal bovine serum (FBS), 2 mM L-glutamine, 1% (v/v) antibiotic-antimycotic, 1 microgram FSH/ml, 10 IU hCG/ml and 1 microgram estradiol/ml. Within each group (APAN or EAN), control follicles were not cultured (0 h), and 2 to 12 follicles per well were incubated under a humidified atmosphere of 5% CO2 in air at 37 degrees C for 24, 48 or 72 h. After 24 h of culture, significantly more (5.3%, 20/374; P < 0.05) oocytes from APAN follicles reached the metaphase I to metaphase II stages (MI to MII) than the percentage of control follicles observed at 0 h (0.9%, 3/318). Continued culture resulted in a further increase (P < 0.05) in the percentage of oocytes reaching MI to MII by 48 h (11.5%, 47/407), which remained unchanged at 72 h (9.9%, 40/404). The percentage of oocytes from EAN follicles reaching MI to MII did not significantly increase after 24 h of culture. However, there was an increase (P < 0.05) by 48 h of culture (8.7%, 11/126), which remained unchanged at 72 h (7.5%, 8/106). These results show that dog oocytes cultured within advanced preantral and early antral follicles in vitro are competent to resume meiosis to the metaphase stage.


Subject(s)
Oocytes/cytology , Oogenesis/physiology , Ovarian Follicle/cytology , Ovarian Follicle/physiology , Animals , Cattle , Cell Separation , Cells, Cultured , Culture Media , Dogs , Estrus , Female , Oocytes/physiology , Time Factors
12.
Vet Surg ; 26(3): 189-94, 1997.
Article in English | MEDLINE | ID: mdl-9150556

ABSTRACT

OBJECTIVE: The purpose of this study was to determine whether an endogenous benzodiazepine receptor ligand (EBZ) was present in the arterial and portal blood of dogs with congenital portosystemic shunts (CPSS). STUDY DESIGN: The presence or absence of an EBZ was determined by the collection of systemic and portal blood from dogs with CPSS. ANIMALS: Fifteen client-owned dogs with a confirmed CPSS. All dogs had historical signs compatible with hepatic encephalopathy. Eight healthy dogs were used as controls. METHODS: In all dogs, systemic blood samples were collected after they were anesthetized. Portal blood samples were collected intraoperatively. EBZ was measured by radioreceptor assay. RESULTS: In 10 of 15 dogs, the portal blood concentration of EBZ was significantly elevated compared with normal dogs (mean, 13.2 +/- 18.55 ng/mL). Five dogs had elevated systemic blood EBZ levels (mean, 8.2 +/- 16.08 ng/mL). Eleven of 15 dogs had a higher portal than systemic blood concentration of EBZ. In contrast, control dogs had extremely low EBZ concentrations detected in their portal blood (mean, 0.16 +/- 0.3 ng/mL) and systemic blood (0 ng/mL). The mean portal and systemic blood concentrations in dogs with CPSS were significantly greater than in control dogs (P < .05). CONCLUSIONS: Elevated blood levels of EBZ were found in dogs with CPSS. The portosystemic gradient noted in 11 dogs suggests the gastrointestinal tract as a possible source for the endogenous ligand. CLINICAL RELEVANCE: Generalized motor seizures have been reported in dogs after surgical correction of CPSS. If the presence of a CPSS results in stimulation of brain receptors for benzodiazepines, post-CPSS ligation seizures may result from a withdrawal of EBZ after ligation of the portosystemic shunt.


Subject(s)
Benzodiazepines/blood , Dog Diseases/blood , Dog Diseases/congenital , Dogs/abnormalities , Portal System/abnormalities , Animals , Benzodiazepines/analysis , Brain Chemistry , Congenital Abnormalities/blood , Congenital Abnormalities/pathology , Congenital Abnormalities/veterinary , Dog Diseases/pathology , Female , Male , Portal System/chemistry , Radioligand Assay/veterinary , Receptors, GABA-A/analysis
13.
Clin Diagn Lab Immunol ; 4(2): 122-6, 1997 Mar.
Article in English | MEDLINE | ID: mdl-9067643

ABSTRACT

A human papillomavirus type 16 (HPV-16) virus-like particle (VLP)-based enzyme-linked immunosorbent assay (ELISA) was used to measure serum antibody to capsid proteins in 376 sexually active college women who were also screened for the presence of genital HPVs by PCR and interviewed for demographic and behavioral risk factors for HPV infection. The seroprevalence was 46% in women with HPV-16 DNA in the genital tract. The corresponding values for women who harbored other HPV types or no HPV in the genital tract were 30 and 19%, respectively (HPV-16 group versus no-HPV group; odds ratio [OR], 3.7; 95% confidence interval [CI], 1.5 to 8.9). The antibody response was significantly higher among women with a high viral load than among those with a low viral load (median optical density value, 0.838 versus 0.137, P = 0.009). Comparable levels of seroreactivity were observed among women infected with HPV types distantly or closely related genetically to HPV-16. Seroreactivity was significantly associated with an age of 25 to 30 years (OR, 2.3; 95% CI, 1.2 to 4.4), three or more lifetime sexual partners (OR, 2.9; 95% CI, 1.1 to 10), and history of a sexually transmitted disease other than HPV (OR, 3.1; 95% CI, 1.5 to 6.3). The percent seropositivity increased linearly with number of lifetime sexual partners until reaching a plateau at 35% for women with more than six partners (chi for linear trend, P < 0.001). The low sensitivity of HPV-16 VLP-based ELISA may limit the usefulness of the assay as a diagnostic test for HPV-16 infection. However, the assay appears to have adequate specificity and should be useful as an epidemiological marker of HPV-16 infection and sexual behavior.


Subject(s)
Antibodies, Viral/blood , Papillomaviridae/immunology , Papillomavirus Infections/immunology , Tumor Virus Infections/immunology , Uterine Cervical Diseases/immunology , Adolescent , Adult , DNA, Viral/genetics , DNA, Viral/isolation & purification , Enzyme-Linked Immunosorbent Assay , Female , Humans , Papillomaviridae/genetics , Papillomaviridae/isolation & purification , Papillomavirus Infections/etiology , Papillomavirus Infections/virology , Risk Factors , Sexual Behavior , Students , Tumor Virus Infections/etiology , Tumor Virus Infections/virology , Uterine Cervical Diseases/etiology , Uterine Cervical Diseases/virology
14.
Dig Dis ; 14 Suppl 1: 20-9, 1996.
Article in English | MEDLINE | ID: mdl-8872449

ABSTRACT

Attempting to forecast future trends in research is difficult enough in any area but is well nigh impossible with the volatile field of hepatic encephalopathy (HE). Undaunted in this review it is suggested that more frequent use of intact animal models of HE to probe the pathogenesis of HE will occur with newly developed pharmacological agents. This process would be greatly facilitated by wide acceptance of a discrete number of reproducible animal models of this syndrome. Brief comments are made on the current status on some of the current hypotheses. Greater utilization of patients with subclinical HE for clinical studies will occur. Continuing interest in nuclear magnetic resonance imaging and spectroscopy findings peculiar to HE will be seen over the next decade.


Subject(s)
Hepatic Encephalopathy/etiology , Animals , Cognition Disorders/etiology , Cognition Disorders/physiopathology , Disease Models, Animal , Forecasting , Hepatic Encephalopathy/physiopathology , Humans , Magnetic Resonance Imaging , Magnetic Resonance Spectroscopy , Neurotoxins/pharmacology , Neurotransmitter Agents/pharmacology , Neurotransmitter Agents/physiology
16.
Hepatology ; 19(5): 1245-50, 1994 May.
Article in English | MEDLINE | ID: mdl-8175148

ABSTRACT

The portacaval shunt rat is often used as a model of human portal-systemic encephalopathy, but its relevance to human portal-systemic encephalopathy remains uncertain. Specifically, it has not been demonstrated that the behavioral changes seen in this model respond to measures known to improve portal-systemic encephalopathy in human subjects. Accordingly, the aim of this study was to establish whether neomycin (an effective treatment for portal-systemic encephalopathy in human beings) added to the drinking water of rats subjected to portacaval shunt reversed or ameliorated the reduction in spontaneous motor activity, which represents a measure of encephalopathy in this animal model. A randomized, placebo-controlled crossover design was used, with each animal serving as its own control. After establishment of baseline activities, 12 rats with portacaval shunt and 12 sham-operated rats were divided into two equal groups: Group A animals received neomycin for 1 wk; this was followed by 1 wk off neomycin; in group B rats, the sequence was reversed. Spontaneous intake of neomycin for 7 days at doses comparable to human usage (0.1 to 0.2 gm/kg/day) was associated with a significant increase in spontaneous motor activity in rats subjected to portacaval shunt (26.4% in group A, 66.3% in group B; p < 0.01 for each protocol) with no significant effect in sham-operated animals. Withdrawal of neomycin resulted in reversal of this effect in group A rats subjected to portacaval shunt. Similar significant improvements for exploratory activity as measured on the basis of nose-hole pokes was also seen in rats subjected to portacaval shunt and given neomycin.(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Behavior, Animal/drug effects , Hepatic Encephalopathy/drug therapy , Neomycin/therapeutic use , Portacaval Shunt, Surgical/adverse effects , Ammonia/blood , Animals , Blood Urea Nitrogen , Disease Models, Animal , Hepatic Encephalopathy/etiology , Hepatic Encephalopathy/psychology , Male , Motor Activity/drug effects , Random Allocation , Rats , Rats, Sprague-Dawley
17.
Alcohol Alcohol Suppl ; 2: 187-90, 1993.
Article in English | MEDLINE | ID: mdl-7748298

ABSTRACT

As will be discussed by Dr E.A. Jones based on observations in animal models of hepatic encephalopathy (HE) in 1984 we commenced our studies on the possible role of "endogenous" benzodiazepines (BZs) in human HE in 1986. Unlike animals our initial studies in humans with HE were complicated by the frequent intake of prescription BZs by these patients. Re-education of our staff on the appropriate use of BZs in patients with liver disease and a carefully devised system to exclude patients who have received prescription BZs in the 3 months preceding hospital admission was instigated before our studies could commence. Initially, we examined CSF of patients with HE for the presence of BZ-like activity using a radiometric assay. Our findings of significantly increased activity have since been confirmed by other investigators. Subsequently we discovered fairly large quantities of BZs in blood and urine of these patients, the level of which correlated with the degree of severity of HE. The ultimate finding that this BZ-like activity was due to diazepam, desmethyldiazepam and some other 1-4 benzodiazepine compounds again raised the possibility that our findings were due to occult ingestion of commercially synthesized BZs even though similar findings were made in animal models of HE. Concurrently with this work it became apparent that the food cycle contains trace amounts of the same BZs. However, the levels of "natural BZs" in food cannot yet explain the high levels of BZs seen in patients with HE. The source for this high level of BZs is currently our main area of research.


Subject(s)
Benzodiazepines/metabolism , Hepatic Encephalopathy/metabolism , Animals , Diazepam/metabolism , Hepatic Encephalopathy/etiology , Humans , Models, Biological , Nordazepam/metabolism
18.
Lancet ; 336(8707): 81-3, 1990 Jul 14.
Article in English | MEDLINE | ID: mdl-1975325

ABSTRACT

Body fluids from patients with hepatic encephalopathy and from controls with no renal or hepatic disease were assayed for benzodiazepine immunoreactivity and benzodiazepine-receptor-binding activity. The subjects had taken no synthetic benzodiazepines for at least 3 months. Benzodiazepine receptor binding in cerebrospinal fluid was significantly higher in hepatic encephalopathy patients than in controls (210 [SE 50.2] vs 40.7 [7.3] oxazepam equivalents [ng/ml]). The severity of hepatic encephalopathy was directly and significantly correlated with the level of benzodiazepine activity by radioreceptor assay or radioimmunoassay in urine and in plasma. Benzodiazepine activity equivalent to levels of more than 900 ng/ml was found in patients with advanced encephalopathy. Although the chemical identity and source of this substance (or substances) are still unknown, its properties and the estimated levels of activity suggest it may have a role in the pathogenesis of the neural inhibition seen in hepatic encephalopathy.


Subject(s)
Benzodiazepines/metabolism , Hepatic Encephalopathy/metabolism , Receptors, GABA-A/metabolism , Benzodiazepines/blood , Benzodiazepines/urine , Hepatic Encephalopathy/blood , Hepatic Encephalopathy/cerebrospinal fluid , Hepatic Encephalopathy/urine , Humans , Radioimmunoassay , Radioligand Assay , Receptors, GABA-A/cerebrospinal fluid , Sampling Studies , Severity of Illness Index
19.
Metab Brain Dis ; 4(4): 253-60, 1989 Dec.
Article in English | MEDLINE | ID: mdl-2557531

ABSTRACT

Based on the reversal of hepatic encephalopathy in animal models with administration of specific benzodiazepine receptor antagonists, it has been postulated that this syndrome may be mediated by an endogenous benzodiazepine-like compound. In this study using a radio-receptor assay, evidence for the existence of this substance has been demonstrated in cerebrospinal fluid but not sera of rabbits with hepatic encephalopathy due to galactosamine-induced hepature failure. Cerebrospinal fluid from rabbits with hepatic encephalopathy caused 36.1 +/- 5.03% displacement of 3H-Ro 15-1788 specific binding to cortical benzodiazepine receptors, compared to 11.7 +/- 0.76% in control animals (P less than 0.01). The benzodiazepine receptor binding activity has been shown to behave as a competitive inhibitor of radiolabeled benzodiazepine receptor binding. The finding of endogenous benzodiazepine binding activity affords a potential explanation for the amelioration of hepatic encephalopathy in this model with the administration of benzodiazepine receptor antagonists.


Subject(s)
GABA-A Receptor Antagonists , Hepatic Encephalopathy/cerebrospinal fluid , Aminocaproates/pharmacology , Animals , Binding, Competitive , Flumazenil/metabolism , Galactosamine , Hepatic Encephalopathy/chemically induced , Hypoxanthine , Hypoxanthines/cerebrospinal fluid , Male , Rabbits , Radioligand Assay , Receptors, GABA-A/metabolism , Vigabatrin
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