Search PubMed⌕ Search

Biomedical subjects

A Frank

Publications and source records attributed to A Frank.

At least 55 records · Page 3Linked to original sources
PubMed2000

Experimental copper and chromium deficiency and additional molybdenum supplementation in goats. I. Feed consumption and weight development.

Secondary Cu deficiency, Cr deficiency and molybdenosis were suggested causes of the 'mysterious' disease afflicting moose (Alces alces L.) in a region in south-west Sweden affected by acid rain. A model experiment with goats was performed to study the clinical chemical parameters, determine the tissue contents of trace and minor elements, to perform pathological and histopathological investigations and to compare the findings with those in moose disease. Twenty 3-month-old male goats were assigned to four dietary treatments (five animals each) in an experiment lasting for 20 months. The four groups in the study were: control group, Cu-deficient group (group 1), Cr-deficient group (group 2), and Cu- and Cr-deficient group (group 3). The animals were fed a basic semi-synthetic diet. At the end of the study the three surviving animals of group 3 were supplemented with additional tetrathiomolybdate (TTM) during the last 2 months. Feed consumption and weight development of the animals were monitored and are presented. The feed consumption of the two Cu-deficient groups of goats (group 1 and group 3) supported the previously described observations in copper deficiency in ruminants, e.g. decreased appetite and feed intake. A previously unreported effect of Cr deficiency in ruminants is now described in goats. Chromium deficiency at adequate Cu supplementation (group 2), caused increased lipid synthesis and a weight gain of 32 kg compared with that of the control group (20 kg). A possible explanation for this unexpected weight increase in only Cr deficiency is discussed. It is concluded that the feeding experiment does not support the hypothesis concerning the relation of Cr deficiency to the moose disease.

Animal Feed↗
PubMed2000

Experimental copper and chromium deficiency and additional molybdenum supplementation in goats. II. Concentrations of trace and minor elements in liver, kidneys and ribs: haematology and clinical chemistry.

Since the mid-1980s a previously undescribed disease has affected moose in south-western Sweden. Investigations made to reveal evidence of a viral aetiology have proved unsuccessful. Trace element studies in apparently healthy moose shot during regular hunting suggested a trace element imbalance, with excessive molybdenum uptake causing secondary copper deficiency. The results also indicated a possible chromium deficiency. To verify this hypothesis, an experimental study was performed in male goats fed a semi-synthetic diet for 1.5 years. The animals were kept and treated in four groups: Controls, Cu-deficient group (group 1), Cr-deficient group (group 2), and combined Cu- and Cr-deficient group with additional supplementation of tetrathiomolybdate for 10 weeks at the end of the study (group 3). The present paper presents tissue contents of trace and minor elements, haematology and clinical chemical parameters. Feed consumption and weight development, as well as pathological and histopathological investigations, were also performed in this study, but these results are presented elsewhere. Changes in trace element concentrations were determined by comparing groups 1, 2 and 3 with the control group. Increased concentrations were observed for Al, Ca, Co, Fe, Mo, Pb, Se in the liver; for Al, Cd, Co, Cr, Mo in the kidneys; and for Mn and Mo in the ribs. Considerable accumulation of Mn in ribs seems to be a useful way to determine oxidative stress. Decreases in Mg and P in all organs and blood serum is characteristic of Cu deficiency and molybdenosis. Also the ratio of Ca/Mg was increased as the result of tissue lesions causing an intracellular increase in Ca and decrease in Mg. The trace element changes observed in group 1 were enhanced by the Mo supplementation in group 3, resulting in characteristic patterns, 'spectra' of changes. The alterations were not as remarkable in group 2 as in the two other groups. However, Cr deficiency considerably influenced Al, Co, V and to a smaller extent also Mn in ribs. In groups 1 and 2, only a few minor changes were detected in the haematological parameters, probably caused by increased adrenal activity after transportation of the animals. In group 3, severe anaemia was present but also a leukopenia. For the different clinical chemical parameters measured, all three groups showed changes, explained mainly by the altered activity of enzymes induced by trace element deficiencies and imbalance. Impaired carbohydrate and lipid metabolism was seen in groups 1 and 3, with increased concentrations of glucose, lactate and triglycerides in serum. Increased concentrations of total bilirubin were measured in all three groups (bile stasis was also seen post mortem). A considerably increased concentration of serum urea was found in group 3, although there were no indications of renal insufficiency or dehydration. Regarding hormones, a substantial decrease was seen in thyroxine (T4) in group 3 as a result of the molybdenosis, but a minor decrease was also seen in group 1. Insulin on the other hand showed increased levels in group 3--and especially in group 2 due to the Cr deficiency but also affected by the molybdenosis. As could be expected, Cu deficiency (groups 1 and 3) caused low levels of caeruloplasmin, secondarily affecting the Fe metabolism in these animals. Protein abnormalities, detected as altered electrophoretic patterns of serum proteins, were also seen mainly in group 3. The findings were also confirmed by multivariate data analysis, where PCA revealed the overall impact of the deficiencies, and PLS regression coefficients indicated the influence on the various analytes.

Animals↗
PubMed2000

Band structure from random interactions

The anharmonic vibrator and rotor regions in nuclei are investigated in the framework of the interacting boson model using an ensemble of random one- and two-body interactions. We find a predominance of L(P) = 0(+) ground states, as well as strong evidence for the occurrence of both vibrational and rotational band structures. This remarkable result suggests that such band structures represent a far more general (robust) property of the collective model space than is generally thought.

Journal Article↗
PubMed2000

Large Proper-Motion Infrared

We report the detection of proper motions in [Fe ii] 1.644 µm emission among the southeasternmost features in the Herbig-Haro object complex GGD 37. Imaging observations were made over a period of 5 yr, at epochs 1993.67, 1996.71, and 1998.68, that reveal proper-motion velocities of 400+/-200 km s-1 at GGD 37:W2 and 850+/-200 km s-1 at a newly identified object, designated GGD 37:RWPF 1. We believe the proper-motion velocity of GGD 37:RWPF 1 is the highest found to date for a Herbig-Haro object. The direction of GGD 37:RWPF 1's proper motion is almost due west, away from the nearby young stellar object complex in Cep A East. GGD 37:W2's direction of proper motion is north/northwest, which does not lead back to any of the compact objects in Cep A East.

Journal Article↗
PubMed2000

A polymorphism in the tau gene associated with risk for Alzheimer's disease.

Searching for tau genetic variations which could be associated with risk for Alzheimer's disease (AD), we have performed a mutational analysis of a region containing the whole exon 11 of the tau gene, which encodes a microtubule binding region critical for tau self-assembly, and we have found a biallelic polymorphism at position +34 of intron 11 (IVS11 + 34G/A). We have analyzed the allelic frequencies of this polymorphism in a case-control sample (167 clinically diagnosed AD and 194 controls) and found that the presence of any G allele (genotypes AG + GG) is associated with a five-fold AD risk in individuals carrying the apolipoprotein E4 allele, strongly suggesting that the combined effect of tau and apoE is relevant in relation with AD pathogenesis.

Age of Onset↗
PubMed2000

Vibrational Excitations of Methane in the Framework of a Local-Mode Anharmonic Model.

The stretching and bending vibrations of methane are described in a local-mode anharmonic symmetry adapted model. Both Hecht- and Fermi-like interactions are considered. We start by establishing the Hamiltonian of the system in terms of internal coordinates and momenta. The Hamiltonian is then rewritten in terms of local creation (annihilation) operators a(dagger)(i)(a(i)), which are later anharmonized by means of the deformation of the harmonic oscillator algebra to the U(2) algebra. This procedure corresponds to the exact Morse result for the dominant matrix elements involved in the harmonically coupled anharmonic oscillator model (HCAO) introduced by Child and Lawton. We have carried out a fit to 40 experimental levels with an rms deviation of 1.17 cm(-1). In addition, we present a description of the dipole transition intensities. Copyright 2000 Academic Press.

Journal Article↗
PubMed2000

Protection by glycine against hypoxic injury of rat hepatocytes: inhibition of ion fluxes through nonspecific leaks.

BACKGROUND/AIMS: Glycine has long been shown to exert strong protective effects against hypoxic injury of hepatocytes. Recently, it was suggested that glycine exerts this protection via inhibition of ligand-gated chloride channels, thereby secondarily inhibiting sodium influx. The purpose of this study was to examine this suggestion. METHODS: Cultured rat hepatocytes were incubated under normoxic and hypoxic conditions. Loss of viability was determined by release of lactate dehydrogenase. Cytosolic ion concentrations were measured using digital fluorescence microscopy. RESULTS: Glycine prevented the hypoxic increase in cytosolic sodium and strongly protected against hypoxic injury. The amino acid was not only protective in Krebs-Henseleit buffer but also in a chloride-free modification thereof and offered additional protection in a sodium-free medium (which already yielded substantial protection in its own right). Glycine also prevented the hypoxic release of the anionic fluorescent dye Newport Green and appeared to prevent the hypoxic entrance of the "nonphysiological" cations cobalt and nickel. CONCLUSION: The results strongly argue against inhibition of ligand-gated chloride channels as being responsible for the potent protective effect of glycine against hypoxic injury of hepatocytes. Instead, they suggest that glycine prevents the formation of nonspecific leaks for small ions including sodium, thereby providing protection.

Adenosine Triphosphate↗
PubMed2000

Lumbar spine curvature during office chair sitting.

Prolonged sitting is generally accepted as a high risk factor in low back pain and it is frequently suggested that a lordotic posture of the lumbar spine should be maintained during sitting. We asked whether the sagittal curvature of the lumbar spine during sitting is affected by the seat tilt, backrest and the direction of the synchronised mechanism of the back and seat tilt (synchro tilt). Two office chairs were tested by multibody analysis interfacing a human model with a chair model. Results indicate that a synchronised mechanism of an office chair representing a posterior tilt of the seat while the backrest is reclined maintains an evenly distributed lumbar lordosis. The segmental angles are between 3.1 and 3.6 degrees at the lumbar vertebrae 1/2-4/5 (L1/2-L4/5). These lumbar spine segmental angles are not sensitive to the backrest height. In contrast, a synchro tilt concept with a reduction of the seat's posterior tilt while the backrest is reclined causes a strong reduction of the lumbar lordosis in backrest recline with a maximum reduction from 11.7 to 2.8 degrees in L4/5. As a consequence of these results, a synchro tilt concept with a posterior tilt of the seat while the backrest is reclined is preferable from the lumbar spine kinematics point of view.

Ergonomics↗
PubMed2000

Predictors of self-help group attendance in cocaine dependent patients.

OBJECTIVE: While referral to self-help groups for patients dependent on drugs other than alcohol has become widespread in the substance abuse treatment field, little is known about the characteristics of people who attend these groups. This study examines particular sociodemographic and clinical characteristics as possible predictors of attendance at self-help groups in the National Institute on Drug Abuse Collaborative Cocaine Treatment Study. METHOD: A multicenter study randomly assigned 487 patients (76.8% men) to one of four psychosocial treatments for cocaine dependence. Patients were treated for 24 weeks. Among other measures, the Weekly Self-Help Questionnaire was administered each week and completed, at least once, by 411 subjects. RESULTS: Approximately two thirds of the patients attended one or more self-help meetings during the 24-week period. Patients initially more likely to attend self-help groups frequently were those who were unemployed, had no religious preference, had more severe baseline drug use and reported treatment for prior substance-related problems. Patients with more severe baseline drug use and those who previously received treatment for substance-related problems were more likely to maintain frequent attendance throughout the study period. Only severity of baseline drug use predicted more frequent attendance during Month 6, although there was a trend in Month 6 favoring more frequent attendance by women. These findings remained significant when treatment condition was added to the models. CONCLUSIONS: Although these findings are consistent with past research on alcohol dependent individuals, they challenge popular clinical notions about the types of people who attend self-help groups. These findings demonstrate that self-help groups can appeal to a wide variety of cocaine dependent patients.

Adult↗
PubMed2000

[Arthroscopic debridement of full-thickness tears of the rotator cuff: a retrospective multicenter study of 283 cases with 3-year follow-up].

PURPOSE OF THE STUDY: The purpose of this study was to assess clinical and radiological course of full-thickness rotator cuff tears treated by arthroscopic debridement and to discuss surgical indications according to patient demands and anatomical lesions. MATERIAL AND METHODS: This retrospective and multicentric study included patients with a minimal 3 years follow-up. The coronal extent of the supraspinatus tear was described as distal, intermediate or retracted. The sagittal extent to the infraspinatus and/or subscapularis and rotator interval was detailed. All patients were evaluated pre and post-operatively using Constant score and radiological A-P view for sub-acromial space measurement. In order to assess the influence of age, anatomical extent of the tear and follow-up, results were analyzed for 4 groups of patients according to their age: group I (19 cases less than 50 years), group II (88 cases from 51 to 60 years), group III (58 cases from 61 to 65 years) and group IV (118 cases over 65 years). Results were finally evaluated according the arthroscopic procedure (isolated acromioplasty and biceps tenotomy, or association of both). RESULTS: 283 patients, aged 63.1 years (range 32 to 82) entered this study. A complete antero-posterior tear of the supra-spinatus tendon was noticed in 93.2 p. 100 of cases. The tear extended to the infraspinatus tendon in 57.3 p. 100, and to the subscapularis tendon in 29 p. 100 of cases. The long head of the biceps was involved in 73 p. 100 of cases. 218 acromioplasties and 116 biceps tenotomies were performed. The 2 procedures were combined in nearly 25 p. 100 of cases. At final revision (mean follow-up of 4.7 years), 98 patients (34.6 p. 100) were very satisfied, 122 (43.1 p. 100) satisfied, 43 (15.2 p. 100) moderatly satisfied and 20 (7.1 p. 100) were disappointed. The average Constant score increased from 42.4 to 67.6 points. The radiological study showed a 1 mm narrowing of the sub-acromial space. Objective results were surprisingly good for group I at a 5.4 years follow-up but dropped from group II to group IV, mainly in relation with the extent of the tear. A deleterious effect of the isolated biceps tenotomy was demonstrated in case of subacromial space superior to 7 mm. Inversely after this procedure patients with a narrowed space improved. DISCUSSION: Even if traditional bias of retrospective and mullticentric study could not be avoided, the large number of patients and long follow-up of this study are superior to most of the published papers. The extent of the supraspinatus tear seems to progress during the 50-60 years decade. Objective results appeared to be much more related to the anatomical lesions than to the arthroscopic procedure. CONCLUSION: This series did not demonstrate a secondary clinical or radiological deterioration after an endoscopic treatment without repair of full-tickness rotator cuff tears. Subacromial decompression and/or biceps tenotomy indications depend on age and extension of the tear.

Adult↗
PubMed2000

Chemical development of latent fingerprints: computational design of ninhydrin analogues.

The design of chemical compounds for development of latent fingerprints is explored computationally. Our main findings are: (a) We show why past attempts to improve the widely used ninhydrin gave relatively small improvements (referring to color only). The optical transition is connected with a "transition core" and therefore is influenced little by substitution on the aromatic rings. (b) We propose new analogues of ninhydrin with a significant potential such as thiono derivatives.

Adsorption↗
PubMed1999

Increased cerebrospinal fluid cAMP levels in Alzheimer's disease.

Since increasing evidence suggests that upregulation of the cAMP-second messenger system may be implicated in Alzheimer's disease neurodegeneration, we have compared the cAMP and cGMP levels in cerebrospinal fluid (CSF) from patients with dementia of the Alzheimer type (DAT, n=10) with those from nondemented age-matched controls (n=10). Our results show that cAMP levels, but not cGMP, are significantly (p<0.01) elevated in CSF from patients with DAT compared to those from nondemented controls. Moreover, a linear regression analysis demonstrated a significant correlation (r=0.62; p<0.01) between cAMP and tau protein levels in CSF when controls and patients with DAT were studied together. These results suggest that upregulation of cAMP-signaling pathway is implicated in Alzheimer's disease physiopathology.

Aged↗
PubMed1999

Psychosocial treatments for cocaine dependence: National Institute on Drug Abuse Collaborative Cocaine Treatment Study.

BACKGROUND: This was a multicenter investigation examining the efficacy of 4 psychosocial treatments for cocaine-dependent patients. METHODS: Four hundred eighty-seven patients were randomly assigned to 1 of 4 manual-guided treatments: individual drug counseling plus group drug counseling (GDC), cognitive therapy plus GDC, supportive-expressive therapy plus GDC, or GDC alone. Treatment was intensive, including 36 possible individual sessions and 24 group sessions for 6 months. Patients were assessed monthly during active treatment and at 9 and 12 months after baseline. Primary outcome measures were the Addiction Severity Index-Drug Use Composite score and the number of days of cocaine use in the past month. RESULTS: Compared with the 2 psychotherapies and with GDC alone, individual drug counseling plus GDC showed the greatest improvement on the Addiction Severity Index-Drug Use Composite score. Individual group counseling plus GDC was also superior to the 2 psychotherapies on the number of days of cocaine use in the past month. Hypotheses regarding the superiority of psychotherapy to GDC for patients with greater psychiatric severity and the superiority of cognitive therapy plus GDC compared with supportive-expressive therapy plus GDC for patients with antisocial personality traits or external coping style were not confirmed. CONCLUSION: Compared with professional psychotherapy, a manual-guided combination of intensive individual drug counseling and GDC has promise for the treatment of cocaine dependence.

Adult↗
PubMed1999

On the Elimination of Spurious Modes in Algebraic Models of Molecular Vibrations.

Spurious states arise naturally in the description of molecular vibrational excitations. In the harmonic approximation such states can be projected out from the physical space exactly. This is in general not the case when anharmonic interactions are considered. We show that within the framework of the symmetry, adapted vibron models which include anharmonicities from the outset, these states can be removed in an exact fashion. Copyright 1999 Academic Press.

Journal Article↗
PubMed1999

Pleural incarceration of the gastric graft after trans-hiatal esophagectomy.

We report on a 73-year-old man who underwent a transhiatal esophagectomy for a T2N1M0 adenocarcinoma of the distal esophagus and developed an incarcerated herniation of the gastric graft through a defect in the right mediastinal pleura. The patient experienced delayed gastric emptying postoperatively, which was initially suggested by barium swallow. The gastric herniation was unidentified by early postoperative swallowing studies and endoscopies. After diagnosis by a later computed tomographic scan and barium study, the herniation was reduced by incising the mediastinal pleura from the diaphragm to the apex of the chest and by plication of the stomach longitudinally in order to reduce its intrathoracic diameter.

Adenocarcinoma↗
PubMed1999

CTLA-4 blockade enhances the immune response induced by mycobacterial infection but does not lead to increased protection.

The murine immune response to a pulmonary mycobacterial infection is slow to develop, allowing bacterial numbers to increase in the lung for several weeks after infection. We sought to enhance the protective immune response induced during Mycobacterium bovis BCG infection by administering an antibody that blocks the interaction of CTLA-4 with its ligands, CD80 and CD86. We found that injection of anti-CTLA-4 monoclonal antibody (MAb) greatly enhanced and accelerated the immune response, as measured by increased cellularity of the draining mediastinal lymph nodes, and enhanced antigen-inducible proliferation and gamma interferon production by mediastinal lymphocytes in vitro. However, despite the apparently enhanced immune response in the mediastinal lymph node following treatment with anti-CTLA-4 MAb, there was no improvement in clearance of mycobacteria in the lungs, liver, or spleen. Examination of the primary site of infection, the lung, revealed that CTLA-4 blockade had no effect on the number or function of lymphocytes infiltrating the infected lung tissue. Taken together, these data suggest that in vivo CTLA-4 blockade enhances mycobacterial-infection-induced lymphocyte expansion and effector cell cytokine production in the draining lymph node but does not alter the number or function of lymphocytes at the primary site of infection and therefore does not lead to enhanced clearance of the infection.

Abatacept↗
PubMed1998

Predictors of dropout from psychosocial treatment of cocaine dependence.

The current study assessed demographic, drug and psychiatric predictors of dropout in the pilot/training phase of a large, multi-site psychotherapy outcome study for patients with cocaine dependence. The different predictors of dropout were assessed throughout the phases of the study: screening, intake, stabilization and assessment phase, and following randomization to treatment. Results showed that (1) younger patients were less likely to keep their intake appointment. (2) Of the patients who had an intake visit, those who did not complete high school and with more days of cocaine use in the previous month were less likely to complete an initial stabilization and assessment phase requiring 1 week of abstinence from all drugs. A survival analysis was used to examine time to dropout for the 286 patients randomized to individual treatment. (3) Again, younger age was associated with dropout after randomization. (4) Drug use variables did not predict time to dropout. (5) Presence of any current Axis I disorder was associated with later dropout from treatment. Minority treatment information seekers and treatment initiators were less likely to go on to complete the full treatment program.

Adult↗