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4.
HIV Med ; 14(2): 120-4, 2013 Feb.
Article in English | MEDLINE | ID: mdl-22780330

ABSTRACT

OBJECTIVES: Financial stress has been identified as a barrier to antiretroviral adherence, but only in resource- limited settings. Almost half of HIV-infected Australian adults earn no regular income and, despite highly subsidised antiretroviral therapy and universal health care, 3% of HIV-infected Australians cease antiretroviral therapy each year. We studied the relationship between financial stress and treatment adherence in a resource-rich setting. METHODS: Out-patients attending the HIV clinic at St Vincent's Hospital between November 2010 and May 2011 were invited to complete an anonymous survey including questions relating to costs and adherence. RESULTS: Of 335 HIV-infected patients (95.8% male; mean age 52 years; hepatitis coinfection 9.2%), 65 patients (19.6%) stated that it was difficult or very difficult to meet pharmacy dispensing costs, 49 (14.6%) reported that they had delayed purchasing medication because of pharmacy costs, and 30 (9.0%) reported that they had ceased medication because of pharmacy costs. Of the 65 patients with difficulties meeting pharmacy costs, 19 (29.2%) had ceased medication vs. 11 (4.1%) of the remaining 270 patients (P < 0.0001). In addition, 19 patients (5.7%) also stated that it was difficult or very difficult to meet travel costs to the clinic. Treatment cessation and interruption were both independently associated with difficulty meeting both pharmacy and clinic travel costs. Only 4.9% had been asked if they were having difficulty paying for medication. CONCLUSIONS: These are the first data to show that pharmacy dispensing and clinic travel costs may affect treatment adherence in a resource-rich setting. Patients should be asked if financial stress is limiting their treatment adherence.


Subject(s)
AIDS-Related Opportunistic Infections/drug therapy , Anti-HIV Agents/administration & dosage , Community Pharmacy Services/economics , HIV Infections/drug therapy , Hepatitis, Viral, Human/drug therapy , Medication Adherence/statistics & numerical data , AIDS-Related Opportunistic Infections/economics , AIDS-Related Opportunistic Infections/epidemiology , Anti-HIV Agents/economics , Australia/epidemiology , Cohort Studies , Female , HIV Infections/economics , HIV Infections/epidemiology , Health Care Costs , Health Services Accessibility , Hepatitis, Viral, Human/economics , Hepatitis, Viral, Human/epidemiology , Humans , Male , Middle Aged , Socioeconomic Factors , Surveys and Questionnaires
5.
Encephale ; 35(4): 377-85, 2009 Sep.
Article in French | MEDLINE | ID: mdl-19748375

ABSTRACT

INTRODUCTION: Although cannabis use may be involved in the aetiology of acute psychosis, there has been considerable debate about the association observed between cannabis use and chronic psychosis. In particular, because of the frequent co-occurrence between schizophrenia and cannabis use, the question has been raised of a causal link between exposure to cannabis as a risk factor and the development of psychosis or psychotic symptoms. OBJECTIVE: The aim of this article was to examine the evidence that cannabis use causes chronic psychotic disorders by using established criteria of causality. These criteria were defined by: biologic plausibility, strength of the interaction between the risk factor and the disease, reprieability of the results, temporal sequence between the exposure to the risk factor and the beginning of the disease and existence of a dose-effect relationship. METHODS: The selected studies were found in Medline using the keywords "cannabis" and "psychosis", "cannabis" and "schizophrenia", "cannabis" and "psychotic symptoms" and "prospective" or "cohort" or "longitudinal". The selected studies were all prospective studies assessing the temporal sequence between cannabis use and emergence of psychosis or psychotic symptoms. The search strategies resulted in 60 records that were screened by reading both titles and abstracts. Seventeen studies were considered eligible, and then, after reading the full text, seven met the inclusion criteria. RESULTS: Together, the seven studies were all prospective cohorts and represented 50,275 human subjects. There were three European studies (from Sweden, Holland and Germany), one from New Zealand and one from Australia. Only one study of the seven did not show a significant association between cannabis consumption and increase of the risk of developing a psychosis. However, this study had some bias, such as low level of cannabis use and the lack of evaluation of cannabis use after inclusion. For the six other studies, data show the existence of a significant association between cannabis use and psychotic disorders (with an increased risk between 1.2 and 2.8 in Zammit et al.'s study), particularly among vulnerable individuals (that is with a prepsychotic state at the time of inclusion). Therefore, all the studies that assessed a dose-effect relationship showed this link between cannabis use and the emergence of psychosis or psychotic symptoms. The fact that all causal criteria were present in the studies suggests that cannabis use may be an independent risk factor for the development of psychosis. Results seem to be more consistent for vulnerable individuals with the hypothesis that cannabis use may precipitate psychosis, notably among vulnerable subjects. In particular, early onset of cannabis use during adolescence should be an environmental stressor that interacts with a genetic predisposition to induce a psychotic disorder. CONCLUSION: The objective of this article was to examine whether cannabis use can be an independent risk factor for chronic psychotic disorders, by using established criteria of causality. Data extracted from the selected studies showed that cannabis use may be an independent risk factor for the development of psychotic disorders. Early screening of the vulnerability to psychotic disorder should permit improved focus on prevention and information about the specific risks related to cannabis use among this population.


Subject(s)
Cannabinoids/toxicity , Marijuana Abuse/epidemiology , Psychoses, Substance-Induced/epidemiology , Psychoses, Substance-Induced/etiology , Causality , Chronic Disease , Cohort Studies , Comorbidity , Dose-Response Relationship, Drug , Humans , Prospective Studies , Risk Factors
6.
Cochrane Database Syst Rev ; (3): CD005194, 2006 Jul 19.
Article in English | MEDLINE | ID: mdl-16856084

ABSTRACT

BACKGROUND: The improved safety profile of benzodiazepines compared to barbiturates has contributed to a high rate of prescription since the seventies. Although benzodiazepines are highly effective for some disorders, they are potentially addictive drugs and they can provide reinforcement in some individuals. OBJECTIVES: To evaluate the effectiveness of pharmacological interventions for benzodiazepine mono-dependence. SEARCH STRATEGY: We searched the Cochrane Drugs and Alcohol Group' Register of Trials (October 2004), the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 4, 2004), MEDLINE (January 1966 to October 2004), EMBASE (January 1988 to October 2004), PsycInfo (1985 to October 2004), CINAHL (1982 to October 2004), Pascal, Toxibase, reference lists of articles. SELECTION CRITERIA: Randomized trials of benzodiazepines dependence management regardless of type, dose (daily and total) and duration of benzodiazepine treatment. DATA COLLECTION AND ANALYSIS: Reviewers independently assessed trials for inclusion, rated their methodological quality and extracted data. MAIN RESULTS: Eight trials involving 458 participants were included. The studies included could not be analysed cumulatively because of heterogeneity of inteventions and participants' characteristics. Results support the policy of gradual rather than abrupt withdrawal of benzodiazepine. Progressive withdrawal (over 10 weeks) appeared preferable if compared to abrupt since the number of drop-outs was less important and the procedure judged more favourable by the participants. Short half-life benzodiazepine, associated with higher drop-out rates, did not have higher withdrawal symptoms scores. Switching from short half-life benzodiazepine to long half-life benzodiazepine before gradual taper withdrawal did not receive much support from this review. The role of propanolol in benzodiazepine withdrawal was unclear; adding tricyclic antidepressant (dothiepin) decreased the intensity of withdrawal symptoms but did not increase the rate of benzodiazepine abstinence at the end of the trial. Buspirone and Progesterone failed to suppress any benzodiazepine symptoms. Carbamazepine might have promise as an adjunctive medication for benzodiazepine withdrawal, particularly in patients receiving benzodiazepines in daily dosages of 20 mg/d or more of diazepam (or equivalents). AUTHORS' CONCLUSIONS: The results of this systematic review point to the potential value of carbamazepine as an effective intervention for benzodiazepine gradual taper discontinuation. Carbamazepine has shown rather modest benefit in reducing withdrawal severity, although it did significantly improve drug-free outcome. Larger controlled studies are needed to confirm these benefits, to assess adverse effects and to identify when its clinical use might be most indicated. Other suggested treatment approaches to benzodiazepine discontinuation management should be explored (antidepressants, benzodiazepine receptors modulator).


Subject(s)
Ambulatory Care , Analgesics, Non-Narcotic/therapeutic use , Benzodiazepines , Carbamazepine/therapeutic use , Substance-Related Disorders/drug therapy , Humans , Randomized Controlled Trials as Topic
7.
Cochrane Database Syst Rev ; (3): CD005336, 2006 Jul 19.
Article in English | MEDLINE | ID: mdl-16856093

ABSTRACT

BACKGROUND: Cannabis use disorder is the most common illicit substance use disorder in general population. Despite that, only a minority seek assistance from a health professional, but the demand for treatment is now increasing internationally. Trials of treatment have been published but to our knowledge, there is no published systematic review . OBJECTIVES: To evaluate the efficacy of psychosocial interventions for cannabis abuse or dependence. SEARCH STRATEGY: We searched the Cochrane Central Register of Trials (CENTRAL) The Cochrane Library Issue 3, 2004; MEDLINE (January 1966 to August 2004), PsycInfo (1985 to October 2004), CINAHL (1982 to October 2004), Toxibase (until September 2004) and reference lists of articles. We also contacted researchers in the field. SELECTION CRITERIA: All randomized controlled studies examining a psychotherapeutic intervention for cannabis dependence or abuse in comparison with a delayed-treatment control group or combinations of psychotherapeutic interventions. DATA COLLECTION AND ANALYSIS: Two authors independently assessed trial quality and extracted data MAIN RESULTS: Six trials involving 1297 people were included. Five studies took place in the United States, one in Australia. Studies were not pooled in meta-analysis because of heterogeneity. The six included studies suggested that counseling approaches might have beneficial effects for the treatment of cannabis dependence. Group and individual sessions of cognitive behavioral therapy (CBT) had both efficacy for the treatment of cannabis dependence and associated problems, CBT produced better outcomes than a brief intervention when CBT was delivered in individual sessions. Two studies suggested that adding voucher-based incentives may enhance treatment when used in combination with other effective psychotherapeutic interventions. Abstinence rates were relatively small overall but favored the individual CBT 9-session (or more) condition. All included trials reported a statistically significant reductions in frequency of cannabis use and dependence symptoms. But other measures of problems related to cannabis use were not consistently different. AUTHORS' CONCLUSIONS: The included studies were too heterogenous and could not allow to draw up a clear conclusion. The studies comparing different therapeutic modalities raise important questions about the duration, intensity and type of treatment. The generalizability of findings is also unknown because the studies have been conducted in a limited number of localities with fairly homogenous samples of treatment seekers. However, the low abstinence rate indicated that cannabis dependence is not easily treated by psychotherapies in outpatient settings.


Subject(s)
Ambulatory Care , Cognitive Behavioral Therapy , Marijuana Abuse/therapy , Humans , Randomized Controlled Trials as Topic
8.
Acta Paediatr ; 93(6): 775-8, 2004 Jun.
Article in English | MEDLINE | ID: mdl-15244226

ABSTRACT

OBJECTIVE: To study the effect of prenatal consultation (PC) with a neonatologist on the incidence and duration of human milk feeding (HMF) in preterm infants. DESIGN/METHODS: A retrospective matched case-control study was preformed at a perinatal centre. Study infants were preterm infants (23-35 wk) whose mothers had received PC emphasizing the importance of HMF. Control infants were matched by birthweight, gestational age and multiplicity. RESULTS: Each group included 29 mothers and 46 preterm infants. Mean gestational age was 30.1 +/- 3 wk in both groups. Mean birthweight was 1329 +/- 489 (PC) and 1334 +/- 441 g (control). PC infants received HMF for significantly longer, both in the hospital and after discharge (hospital: PC 37 +/- 34 d vs control 15 +/- 19 d, p = 0.001; discharge PC 60 +/- 57 d vs control 21 +/- 32 d; p = 0.0001). No significant difference in neonatal morbidity was detected between the groups. CONCLUSIONS: PC is associated with significantly longer HMF in preterm infants, both in hospital and after discharge.


Subject(s)
Breast Feeding/statistics & numerical data , Infant, Premature , Milk, Human , Referral and Consultation , Adult , Case-Control Studies , Female , Gestational Age , Humans , Infant, Newborn , Logistic Models , Male , Prenatal Care , Retrospective Studies
9.
J Clin Pharmacol ; 32(6): 546-52, 1992 Jun.
Article in English | MEDLINE | ID: mdl-1634642

ABSTRACT

Dipyridamole stress thallium imaging has been widely employed to diagnose and assess the extent of coronary heart disease in patients who cannot exercise. When oral dipyridamole administration was used, a wide range of results for sensitivity, specificity, hemodynamic response and side effect profile has been reported. The authors hypothesized that the formulation used for oral administration of dipyridamole plays a major factor in this variability, and that the pulverized form of dipyridamole will achieve faster and more consistent response than the standard tablet form. The authors studied 13 consecutive patients who underwent thallium scintigraphy. Eight patients received dipyridamole pulverized and dissolved in a glycol/aqueous base diluent (group A), and five patients received the standard form of dipyridamole (group B). In group A, mean peak systolic blood pressure decreased from 142 +/- 31 (mean +/- standard deviation) to 109 +/- 30 (P = .05), and mean diastolic blood pressure decreased from 76 +/- 14 to 51 +/- 5. The mean heart rate changed from 78 +/- 26 to 80 +/- 10. In group B, baseline systolic blood pressure was 165 +/- 12 and decreased to 156 +/- 7 at 45 minutes and to 155 +/- 14 at 90 minutes. Heart rate increased from baseline of 69 +/- 9 to 75 +/- 8 at 45 minutes and to 76 +/- 11 at 90 minutes. At 45 minutes, the systolic blood pressure of the 8 group A patients dropped by 33 +/- 19 mm Hg, whereas group B's changed by 9 +/- 6 mm Hg (P less than .005).(ABSTRACT TRUNCATED AT 250 WORDS)


Subject(s)
Dipyridamole , Heart/diagnostic imaging , Thallium Radioisotopes , Administration, Oral , Aged , Blood Pressure/drug effects , Chemistry, Pharmaceutical , Coronary Disease/diagnostic imaging , Coronary Disease/physiopathology , Dipyridamole/adverse effects , Heart Rate/drug effects , Humans , Male , Middle Aged , Radionuclide Imaging , Suspensions , Tablets , Time Factors
10.
Cancer Immunol Immunother ; 33(4): 223-30, 1991.
Article in English | MEDLINE | ID: mdl-2059966

ABSTRACT

Measurements in cancer patients showed that the pH of tumors averages 0.8 unit lower than that of the surrounding normal tissues, confirming published work. Based on this, the anti-carcinoma monoclonal antibody (mAb) L6 was used to prepare immunoconjugates with daunomycin (DM), the drug being released at the acidic pH of the tumor. A direct linking of the aconitic derivative of DM (AcoDM) to mAb L6 led to conjugates that either had a low drug/antibody ratio (less than 5:1) or precipitated in vitro. In order to increase the drug load and avoid precipitation, several biopolymers were tested as spacers between the drug and the L6. To attach the polymer derivative to the mAb, the former was maleimidized and the mAb was thiolated. The AcoM/mAb ratio obtained was 20, and the mAb retained its highly specific binding to tumor cells. At pH 6 the AcoDM-L6 conjugate was toxic to cultured C-3347 carcinoma cells with an inhibitory concentration (IC50) of 5 micrograms/ml. The conjugate was less effective than the free DM with an IC50 of 0.2 micrograms/ml. The L6 alone was not toxic. At a tumor pH of 6.5, 15% of the AcoDM was released. The amount of released drug reached a maximum 24-48 h after exposure to the acidic medium. In vivo localization studies demonstrated a similar tumor uptake of the conjugate and mAb L6 with 18% of the injected dose/g tumor and a maximum uptake in tumor 48 h after injection. Our data indicate that it is possible to construct conjugates based on a pH-sensitive linker that can be targeted successfully to a tumor with release of a portion of the drug at the tumor site, but testing is needed to establish whether such release has anti-tumor activity in vivo and offers an advantage over treatment with unconjugated drug.


Subject(s)
Daunorubicin/pharmacokinetics , Immunotoxins/pharmacokinetics , Neoplasms/metabolism , Aged , Animals , Antibodies, Monoclonal/administration & dosage , Daunorubicin/administration & dosage , Female , Humans , Hydrogen-Ion Concentration , Immunotoxins/chemistry , Male , Mice , Middle Aged , Tissue Distribution , Tumor Cells, Cultured
11.
Radiother Oncol ; 15(3): 295-305, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2772257

ABSTRACT

L6 is a murine monoclonal antibody (MAb) binding to cells of most human carcinomas, mediating antibody-dependent cellular cytotoxicity and complement-dependent cytotoxicity, and inhibiting tumor growth in nude mice [10]. Fab and F(ab')2 fragments of L6, as well as intact MAb, have been evaluated for immunospecific localization in nude mice xenografted with a human lung carcinoma. They were compared with preparations of an isotype-matched control immunoglobulin, P1.17, after labelling with 125I or 131I. L6 Fab fragments prepared from MAb L6 and labelled with 67Ga via desferrioxamine were also tested. The data suggest that MAb L6 may be useful for in vivo detection of human carcinomas.


Subject(s)
Antibodies, Monoclonal , Neoplasms, Experimental/metabolism , Animals , Female , Gallium Radioisotopes , Immunoglobulin Fab Fragments , Iodine Radioisotopes , Metabolic Clearance Rate , Mice , Mice, Inbred BALB C , Mice, Nude , Neoplasm Transplantation , Neoplasms, Experimental/immunology , Tissue Distribution
12.
Biochim Biophys Acta ; 995(3): 295-300, 1989 May 01.
Article in English | MEDLINE | ID: mdl-2495819

ABSTRACT

The kinetic behavior of fibrin clot lysis as induced by tissue-type plasminogen activator (t-PA) was studied using proton magnetic resonance (PMR) and a release assay of fibrin labeled with technetium-99m isotope (99mTc). The lysis pattern of the preformed clot was examined as a function of gradual changes in the amounts of added t-PA and deactivated t-PA. The behavior of fibrinolysis was found to depend strongly on the amount of t-PA in the assay, which markedly affects the lysis rate of fibrin. The changes induced by the lysis were reflected in pronounced prolongation of the transverse relaxation time. The PMR and the radioisotope release measurements point to the possibility that at least two steps are involved in the mechanism of lysis. The PMR seems to be associated with structural features of the clot and reflects the liberation of compartmentalized water from the clot, while the 99mTc analysis reflects the further fragmentation of fibrin.


Subject(s)
Fibrinolysis , Tissue Plasminogen Activator , Animals , Blood Coagulation , Cattle , Fibrin/physiology , Humans , Hydrolysis , Kinetics , Magnetic Resonance Spectroscopy , Technetium , Water
13.
Biochim Biophys Acta ; 991(1): 62-7, 1989 Apr 25.
Article in English | MEDLINE | ID: mdl-2496763

ABSTRACT

The clot uptake of labeled active and inhibited t-PA was compared. The most efficient inhibition was obtained with diisopropyl fluorophosphate (DFP) after 4 h incubation at room temperature. Enzyme activity was followed by fibrin-plate assay, radioactivity-release technique and proton magnetic resonance (PMR). The novel PMR method developed by us is sensitive to the effect of as low as nanogram amounts of t-PA on the interaction between the fibrin and the compartmentalized water trapped in the clot. Binding of labeled enzyme to fibrin-coated plates showed that the deactivation by DFP did not impair the affinity of t-PA for fibrin. A rapid binding of 125I-labeled t-PA to the clot occurred, which reached a maximum in 30 min and declined with time. This pattern was explained by consecutive clot binding and lysis. The binding of DFP-t-PA to the clot differed markedly from that of the active protein; 2 h post-incubation the uptake of DFP-t-PA was more than double that of the untreated t-PA. Parallel measurements in clots prepared from human blood showed a qualitatively similar trend. The biodistribution of radiolabeled t-PA in mice was similar for the active and inhibited forms. Blood activity reached 10% of the injected dose within 10 min. DFP-t-PA may prove to be a useful reagent for in-vivo localization of thrombi.


Subject(s)
Blood Coagulation/drug effects , Fibrin/metabolism , Tissue Plasminogen Activator/metabolism , Animals , Biological Availability , Female , Fibrin Fibrinogen Degradation Products/metabolism , Fibrinolysis/drug effects , Half-Life , Humans , Isoflurophate/blood , Isoflurophate/pharmacology , Isotope Labeling , Magnetic Resonance Spectroscopy/methods , Mice , Phenylmethylsulfonyl Fluoride/pharmacology , Recombinant Proteins/metabolism , Thrombosis/metabolism , Tissue Plasminogen Activator/antagonists & inhibitors , Tissue Plasminogen Activator/blood
14.
Cancer Res ; 48(3): 624-7, 1988 Feb 01.
Article in English | MEDLINE | ID: mdl-3335025

ABSTRACT

Cultured human melanoma, lung carcinoma, and colon carcinoma cells were isotope labeled and incubated with a combination of effector cells and mouse monoclonal antibodies to tumor-associated cell surface antigens. The former were derived from the peritoneal cavity of mice or from peripheral blood of healthy human subjects. Monoclonal antibodies MG-21, 96.5, and L6, which are IgG3, IgG2a, and IgG2a, respectively, were all cytolytic when added in the presence of mouse effector cells to target cells expressing the relevant antigens. MG-21 and L6 were cytolytic also with human effector cells, while monoclonal antibody 96.5 was not. The effector cells attached to plastic surfaces, stained with neutral red, were peroxidase positive and mediated their effect over a 24- to 72-h time period as compared to the 4 h generally sufficient for antibody-dependent cellular cytotoxicity by natural killer cells. In tests on human effector cells with a fluorescence-activated cell sorter, they stained with antibody LCM-3C10 to the CD14 antigen, as well as with antimonocyte antibody 61D3. The cytolytic effect of human effector cells and antitumor antibody was not abolished by incubation with antibodies FC2 or 60.3 to CD16 and CD18, respectively, known to interfere with the antibody-dependent cellular cytotoxicity activity and natural killing of natural killer cells. This suggests, together with the other findings, that the effector cells were macrophages.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antibodies, Neoplasm/immunology , Antibody-Dependent Cell Cytotoxicity , Macrophages/immunology , Tumor Cells, Cultured/immunology , Animals , Ascitic Fluid/cytology , Humans , In Vitro Techniques , Killer Cells, Natural/immunology , Melanoma, Experimental/immunology , Mice
15.
Radiother Oncol ; 8(2): 129-35, 1987 Feb.
Article in English | MEDLINE | ID: mdl-3562892

ABSTRACT

Labeling of human sarcoma-associated murine monoclonal antibody (MAb) 23H7 with 67Ga and 111In by the bifunctional ligand method is reported. 67Ga was chelated to the MAb via desferrioxamine B and 111In via the cyclic anhydride of DTPA. Higher specific activity was obtained with 67Ga (4-5 microCi/micrograms) as compared with 111In (2 microCi/micrograms). The binding capacity of the MAb was confirmed by repeated indirect immuno-fluorescence assays performed before and after labeling. A fast blood clearance was observed: 33% recovered dose (R.D.) blood level 3 h post-injection as compared with 56% after injection of control polyclonal IgG. Preliminary results on chemically induced sarcoma bearing mice showed a relatively high tumor uptake of the labeled antibody.


Subject(s)
Antibodies, Monoclonal , Gallium Radioisotopes , Indium , Iodine Radioisotopes , Isotope Labeling/methods , Radioisotopes , Sarcoma/immunology , Animals , Antibodies, Monoclonal/metabolism , Antibodies, Neoplasm , Humans , Mice , Sarcoma, Experimental/metabolism , Tissue Distribution
16.
NCI Monogr ; (3): 153-5, 1987.
Article in English | MEDLINE | ID: mdl-3821913

ABSTRACT

Monoclonal antibody (MAb) 23H7 is a hybridoma-derived IgG that is generated following fusion of mouse myeloma cell line P3U1 and spleen cells from BALB/c mice hyperimmunized with a human fibrosarcoma. It detects a mesenchymal antigen of 23KD expressed on human sarcoma tissues and other neoplasms, including myeloid leukemias, but it rarely binds to normal tissues. The MAb 23H7 was labeled with 67Ga and 111In using the bifunctional ligand method. The 67Ga was chelated to the MAb via desferrioxamine B, while 111In was chelated via the cyclic anhydride of diethylenetriamine pentaacetic acid. Higher specific activity was obtained with 67Ga than with 111In (4.5 and 2 muCi/microgram, respectively); both gave stable complexes. When 23H7 was labeled with 125I, considerable breakdown was observed. This, together with the physical shortcomings of this isotope, emphasizes the advantages of labeling with 111In and 67Ga. The rapid blood clearance of the labeled sarcoma-associated MAb may be beneficial for early tumor uptake and for imaging shortly after injection.


Subject(s)
Antibodies, Monoclonal , Fibrosarcoma/radiotherapy , Gallium Radioisotopes , Indium , Iodine Radioisotopes , Animals , Antibodies, Neoplasm , Fibrosarcoma/immunology , Humans , Mice , Mice, Inbred ICR , Neoplasm Transplantation , Radioisotopes
17.
J Neurochem ; 44(5): 1391-402, 1985 May.
Article in English | MEDLINE | ID: mdl-3989537

ABSTRACT

Changes in plasma membrane potential of isolated bovine adrenal chromaffin cells were measured independently by two chemical probe methods and related to corresponding effects on catecholamine secretion. The lipophilic cation tetraphenylphosphonium (TPP+) and the carbocyanine dye 3,3'-dipropylthiadicarbocyanine [DiS-C3-(5)] were used. The necessity of evaluating the subcellular distribution of TPP+ among cytoplasmic, mitochondrial, secretory granule, and bound compartments was demonstrated and the resting plasma membrane potential determined to be -55 mV. The relationship between membrane potential and catecholamine secretion was determined in response to variations in extracellular K+ and to the presence of several secretagogues including cholinergic receptor ligands, veratridine, and ionophores for Na+ and K+. The dependence of potential on K+ concentration fit the Goldman constant field equation with a Na/K permeability ratio of 0.1. The dependence of both K+- and veratridine-evoked catecholamine secretion on membrane potential exhibited a potential threshold of about -40 mV before a significant rise in secretion occurred. This is likely related to the threshold for opening of voltage-sensitive Ca2+ channels. Acetylcholine and nicotine evoked a large secretory response without a sufficiently sustained depolarization to be detectable by the relatively slow potential sensitive chemical probes. Decamethonium induced a detectable depolarization of the chromaffin cells. Veratridine and gramicidin evoked both membrane depolarization and catecholamine release. By contrast the K ionophore valinomycin evoked significant levels of secretion without any depolarization. This is consistent with its utilization of an intracellular source of Ca2+ and the independence of its measured secretory response on extracellular Ca2+.


Subject(s)
Adrenal Medulla/physiology , Carbocyanines , Catecholamines/metabolism , Chromaffin System/physiology , Onium Compounds , Organophosphorus Compounds , Quinolines , Acetylcholine/pharmacology , Animals , Cattle , Cell Membrane/physiology , Decamethonium Compounds/pharmacology , Fluorescent Dyes , Ionophores/pharmacology , Kinetics , Membrane Potentials , Nicotine/pharmacology , Potassium/pharmacology , Receptors, Cholinergic/physiology , Veratridine/pharmacology
18.
Int J Appl Radiat Isot ; 35(2): 99-102, 1984 Feb.
Article in English | MEDLINE | ID: mdl-6706430

ABSTRACT

The preparation of [99mTc]fibrinogen is described. The following factors which could affect the quality of this preparation were studied: pH, SnCl2 and protein concentrations, pre- and post-labeling incubation times and labeling temperature. A 90% labeling yield was achieved by incubating fibrinogen with SnCl2 at pH 9.8 for 22 h before adding the TcO-4 solution. The product obtained was stable and was 85% clottable. The x-ray fluorescence technique was employed to measure the amount of bound tin at different times.


Subject(s)
Fibrinogen , Technetium , Tin Compounds , Humans , Hydrogen-Ion Concentration , Isotope Labeling/methods , Temperature , Time Factors , Tin
19.
Int J Appl Radiat Isot ; 35(1): 69-70, 1984 Jan.
Article in English | MEDLINE | ID: mdl-6698629

ABSTRACT

A method for the labeling of human fibrinogen with 111In is reported. The cyclic anhydride of DTPA, either dissolved in dimethyl sulfoxide or as the solid, is first covalently attached to the protein. The modified fibrinogen is then labeled with [111In]acetate, with an average yield of 90 +/- 3%. The product obtained is highly clottable and stable in vitro and has potential applications in imaging studies.


Subject(s)
Fibrinogen , Indium , Radioisotopes , Humans , Isotope Labeling/methods
20.
Article in English | MEDLINE | ID: mdl-6226622

ABSTRACT

The evolutionary significance of allelic isozyme polymorphisms in several Mediterranean marine organisms was tested initially by post-hoc gene frequency analyses at 11-15 gene loci in natural populations of barnacles, Balanus amphitrite, under thermal [Nevo et al, 1977] and chemical [Nevo et al, 1978] pollutions. We next carried out pre-hoc controlled laboratory experiments to test the effects of heavy metal pollution (Hg, Zn, Cd) on genotypic frequencies of 15 phosphoglucomutase (PGM) genotypes in thousands of individuals of the shrimp Palaemon elegans [Nevo et al, 1980, 1981a, and the present study]. Similarly, we tested the effects of Hg, Zn, Cd, Pb, Cu pollutions on the genotypic and allelic frequencies of five phosphoglucose isomerase (PGI) genotypes in the two close species of marine gastropods, Monodonta turbinata and M turbiformis [Lavie and Nevo, 1982, and the present study]. In both the thermal and chemical pollution studies, we established in repeated experiments statistically significant differences of allele frequencies at 8 out of 11 (73%) and 10 out of 15 (67%) gene loci, respectively, between the contrasting environments in each. While no specific function could be singled out in the post-hoc chemical study due to the complex nature of polluted marine water, temperature could be specified as the primary selective agent in the thermal study. The strongest direct and specific evidence for significant differential survivorship among allelic isozyme genotypes was obtained in the pre-hoc studies in Palaemon and Monodonta. Their differential viability was probably associated with the different degree of heavy metal inhibition uniquely related to each specific pollutant. Furthermore, we demonstrated in the two closely related Monodonta species parallel genotypic differentiation as a response to pollution. Our results are inconsistent with the neutral theory of allelic isozyme polymorphisms and appear to reflect the adaptive nature of the allelic isozyme polymorphisms studied. Allelic isozyme genotypes are sensitive to and vary with the quality and quantity of specific pollutants. Therefore, they can provide precise genetic indicators of the effects of pollution on the short- and long-term genetic changes of populations. Ideally, in different marine species specific genetic loci, either singly or in combination, may prove sensitive markers to different pollutants and could easily be assayed by quick electrophoretic tests and be used as genetic monitors. An extensive search for the appropriate enzymatic systems in various relatively sedentary marine species exposed to pollutants is therefore urgent.


Subject(s)
Isoenzymes/genetics , Polymorphism, Genetic , Water Pollution/adverse effects , Adaptation, Physiological , Alleles , Animals , Biological Evolution , Decapoda/genetics , Environment , Glucose-6-Phosphate Isomerase/genetics , Metals/toxicity , Mollusca/genetics , Phosphoglucomutase/genetics
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