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PubMed1991

[Modern drug therapy in alcoholism].

The recent investigations on biochemical and biophysical mechanisms of ethanol in acute intoxication, tolerance and physical dependence suggest that the cell membrane, intracellular metabolism and central neurotransmitters are involved. In acute intoxication ethanol increases the "fluidity" of the cell membrane and stimulates the central gabergic system. In alcoholics, the body adapts, and in the presence of ethanol, the cell membrane becomes more "rigid" and the gabergic system hypoactive. When alcohol intake is discontinued the hypoactivity of the gabergic system is unmasked and it is manifested as withdrawal syndrome. The alcohol intake compensates for the clinical symptoms of decreased gabergic activity and thereby continuously prevent the onset of withdrawal symptoms. On the other hand, intact central noradrenergic and 5-hydroxytryptaminergic systems as well as the neuropeptide vasopressin maintain the tolerance. After withdrawal syndrome, membrane alterations and the state of diminished gabergic activity gradually return to normal. This period of slow recuperation corresponds to the subacute withdrawal syndrome. In this period, there is a continuous desire for alcohol intake. Further, alcoholics, in this situation, are very vulnerable with feelings of insecurity, fragility and isolation. All these factors additionally induce a latent desire for ethanol. It follows then that a stimulation of decreased gabergic activity is a new approach in drug therapy of alcoholism. One of these new stimulants is acamprosate. The new substance is a structural analogue of GABA and acts as an agonist on gabergic receptors. Therefore, acamprosate improves the central gabergic activity. Alcoholics treated with acamprosate stated that they no longer felt a desire for alcohol intake. In this way, acamprosate maintains the abstinence for several months during the post-withdrawal phase.(ABSTRACT TRUNCATED AT 250 WORDS)

Alcoholism↗

PubMed1991

[The Aeromonas genus].

Aeromonas hydrophila manifested itself since its discovery in 1891 as a pathogen of cold-blooded and warm-blooded animals and man. Aeromonads cause intestinal and non-intestinal disease. The genus Aeromonas comprises: A. hydrophila, A. sorbria, A. caviae, A. veronii, A. schubertii, i.e. mesophilie species and as to psychrophilie immobile species. A. salmonicida and A. media. For warm-blooded animals and man mesophilie motile species are important as pathogens. A. veronii is an ornithine-decarboxylase positive species, A. schubertii is mannitol-negative, A. caviae is non-haemolytic and VP-negative. It is difficult to differentiate. A. hydrophila with aerogenic and anaerogenic strains from A. sobria. Several practical differential diagnostic tests were suggested by Janda et al. and Joseph et al.: hydrolysis of esculine, KCN, arabinose and salicin are usually positive in A. hydrophila, in A. sobria usually negative. Existing species of mesophilie aeromonads, however, do not correspond to some strains which are found. Therefore Arduino et al. divided their aeromonads into DNA-hybridization groups: for A. hydrophila there were 5, for A. caviae 2 and for A. sobria 1 hybridization group. Biochemisal characteristics corresponded to the hybridization groups. For isolation of aeromonads from faeces selective media with ampicillin must be used and possibly enrichment in alkaline peptone water. Evidence of pathogenity factors is similar as in E. coli,: detection of adhesins and enterotoxin or cytotoxin by means of tests commonly used in cholera and E. coli. The types of adhesins are differentiated by means of fucose- galactose- and mannose resistant haemagglutination.(ABSTRACT TRUNCATED AT 250 WORDS)

Aeromonas↗

PubMedDate not supplied

[Euthanasia and the physician].

The problem of Euthanasia is approached in the light of the Hippocratic principles, which have not changed with time but have only been adapted to new scientific and social developments. The definition of what constitutes Euthanasia is clarified and the need to avoid that semantic mutations may manipulate ideas is stressed, so that what is certainly wrong does not seem to appear as right. The uniqueness and individuality of the human being is emphasized as well as the commitment of doctors to their patients wellbeing, although at times a balance may be needed in relation to some apparently conflicting interests of society as a whole. The importance of the doctor/patient relationship is stressed, particularly in the final stages of terminal disease. Decisions concerning life and death, although preferably to be shared, still rest most times upon the doctor's shoulders alone. The respect for the wishes of the patients, their right to know the truth and its limits, the use of the living will, the right to die in dignity, the use of ordinary or extraordinary means of treatment, the concept of brain death and the rules for resuscitation, are commented upon. In all cases, the need for a global and individualized approach is mandatory before any final decision is made. Total respect for human life, from its beginning to its end is emphasized, intentional killing, for whatever reason or motivation, is firmly rejected. Reference is made to national and international codes of ethics as well as to declarations and statements of the World Medical Association.(ABSTRACT TRUNCATED AT 250 WORDS)

Euthanasia↗

PubMed1989

[Three dimensional study of the pulpal vascular changes during inflammation].

In this study, the changes of canine pulpal vascular architecture, at various stage of growth when subjected so acute and chronic inflammation were examined through a scanning electron microscope using vascular corrosive resin casts. The following results were obtained. 1. The sites of leakage of MMA resin out of the blood vessels coincided with the site where microleakage occurred, thus suggesting that resin cast method is a useful technique to study the area where vascular permeability was increased. 2. In an acute inflammation, leakage of resin out of blood vessels was mainly observed at the sites of venular network (VN) and venous capillaries, and these could be discriminated by use of the casts method. This is in accordance with the result by Tsuchiya, Magino and Palade, where they showed that vascular permeability was preferentially observed in venule and venous capillaries. 3. In pulp with a lesser number of venules during the stage of late maturation, leakage of resin was observed from those surviving venules to the bundle of main blood vessels. 4. Leakage of resin was not observed in the terminal capillary network (TCN), but in the capillary network (CN) and VN, especially just beneath the dentin, where cavity preparation with a water spray was performed. Accordingly, the generation of heat during cavity preparation was thought to be the main reason for disturbance of the pulp. 5. Severe case of suppurative and chronic ulcerative pulpitis were generated within one week after cavity preparation. The vascular architecture was characterized by a dense granular capillary network facing the ulcerative surface. 6. One week after pulpal exposure, at the stage of early maturation of pulp, the granulated blood vessels located within the exposed pulp had a tendency to shift to a pulp polyp. And the granulated blood vessels after two months showed a pulp polyp. 7. At the late maturation stage of pulp, development the pulp chamber and dentin tubules were saturated by resin cast method, suggesting the possibility of leakage out of blood vessels and the death of some odontoblasts. The pulp at this stage shifted to a gangrous pulp. 8. In conclusion, the pulpal vascularity constantly undergoes morphologic changes incidential to various condition such as growth, maturation and inflammation. Basically, vascularity of dental pulp consists of three major layers, that is TCN, CN and VN. When it comes to the maturation stage, owing to the apposition of secondary dentin, the pulp cavity will become narrow and the vasculation within it will undergo a histologic change. As a result, most of the VN disappears.(ABSTRACT TRUNCATED AT 400 WORDS)

Dental Pulp↗

PubMed1989

[New advances in rheumatology].

(1) Molecular pharmacology which is a starting to reach the market place, what is expected to be the next big step in the biotechnology revolution: the creation of complex compounds that are custom-designed to meet human needs. The new technology known as protein engineering promises to take us one step further by modifying natural proteins or by creating new ones especially by using somatic gene transfer and germ gene transfer and its influence on progeny. By doing this we hope to control some of genetic diseases as well to find cure for arthritis. (2) Demonstration of infective agent as a cause of Lymes Arthritis excellent example were a good epidemiologic study culminate in finding the causative agent Borrelia burgdorferi. (3) Description of new syndromes: a) the anticardiolipin syndrome by defining the role of anticardiolipin, antiphospholipid antibodies and presence of lupus anticoagulant and false reactive test for syphilis. Their role in vascular thromboses, recurrent abortions and different forms of lupus. The role of those autoantibodies as a marker in young people with myocardial infraction; b) mixed connective tissue disease as emphasized by extractable nucleolar antigen, and c) CREST syndrome and its detection by anticentromere antibodies. (4) Role of magnetic resonance imaging in diagnosing musculoskeletal disorders showing excellent contrast between soft tissue and bone. Ability to see tendons, ligament, cartilage (fibrocartilage from hyaline cartilage), synovial hypertrophy from effusions. Role in early non invasive detaction of ischemic necrosis of bone which is frequently seen in patients with lupus and patients treated with high doses of corticosteroids, being more sensitive than radiology, computed tomography or radionuclide bone scanning.(ABSTRACT TRUNCATED AT 250 WORDS)

Collagen Diseases↗

PubMed1989

[Taxonomic studies of the Streptococcus intermedius strains isolated from human oral cavities].

Human oral isolates of Streptococcus intermedius, which were biochemically identified, have been classified into 5-Serogroups (I-V). Selecting some representive stock cultures together with the type strain ATCC 27335, comparisons were carried out between them in terms of cell extractable proteins, G + C mol% values, DNA-DNA homology and DNA restriction fragments. Since the taxon of S. intermedius has not been clarified, comparison was also made between the above strains and the type strains of the "Streptococcus anginosus-milleri Group", Streptococcus anginosus, "Streptococcus milleri" and Streptococcus constellatus, which were thought to be related to S. intermedius. 1. G + C mol% of S. intermedius ATCC 27335 was 38.0 +/- 0.28. The values of all the isolates tested ranged from 37.0 to 38.8. On the other hand, the values of the type strains of the "S. anginosus-milleri Group" were 38.0-38.8. 2. Under stringent conditions of DNA-DNA hybridization, all the isolates showed more than 66.7% homology with S. intermedius ATCC 27335, demonstrating that these strains belonged to the same species. On the other hand, S. anginosus ATCC 33397, "S. milleri" NCTC 11169 and S. constellatus ATCC 27823 hybridized at levels of 50%, 53% and 28%, respectively. Consequently, it was impossible to classify these strains as being the same species as S. intermedius. 3. When the DNA restriction fragments were compared by PAGE, the strains of Serogroups I and V showed the same pattern, respectively. The strains of Serogroups II and III, however, showed two different patterns, and these of Serogroup IV showed five different patterns. DNA fragments specific to S. intermedius could not be identified. 4. When cell extractable groups were compared by SDS-PAGE, the strains of Serogroups I and V showed identical patterns. The strains of Serogroup III showed 2 different patterns and those of Serogroup IV showed 5 patterns. These results reflected those of the DNA restriction analysis. However, the strains of Serogroup II showed the same protein pattern, although 2 different patterns were observed in DNA restriction fragments. Unique proteins, which were not detected in the proteins extracted from the type strains of the "S. anginosus-milleri Group", were observed in the cell proteins of S. intermedius strains. 5. The results of DNA-DNA hybridization and the existence of unique extractable proteins together with the chondroitinase productivity suggest that the strains of S. intermedius might represent a particular taxon among the strains of the "S. anginosus-milleri Group".(ABSTRACT TRUNCATED AT 400 WORDS)

Humans↗

PubMed1988

[Morphological problems in cardiac hypertrophy].

Ventricular hypertrophy is categorized as (1) volume hypertrophy (eccentric hypertrophy or hypertrophy with dilatation), and (2) pressure hypertrophy (concentric hypertrophy or hypertrophy without dilatation). Hypertrophy per se is considered as a reaction to hemodynamic overload, both in occasions of excessive volume and of elevated pressure except in (idiopathic) cardiomyopathies. In patients with volume hypertrophy, some alteration of myocardial architecture is inevitable if the volume load exceeds a critical degree. Such alteration is characterized by deterioration of the median circular muscular layer of the ventricle resulting from over-stretching of the horizontally-coursing myocyte bundles. Hypertrophy of the inner oblique muscular layer of the left ventricle in cases with mitral regurgitation, and of the outer oblique muscular layer in cases with aortic regurgitation develops according to the changing configuration of the left ventricle; globular in the former, and elongated in the latter. In patients with pressure hypertrophy, there is some increase of the myocyte mass, with a disarrangement at the anterior triangle of the interventricular septum. The latter is physiologically situated at the anterior margin of the septum between the outer and median layers of both the ventricles. This seems to be a prelude to thickening of the septum and tends to hypertrophy of the free wall. A reduction in the deranged myocyte mass due to fibrosis or adiposis corresponds to arrest of the active hypertrophic process, and it may be the beginning of decompensation of cardiac function. Peculiar modes of dilatation and hypertrophy in cardiomyopathies have common denominators with those of known etiologies.(ABSTRACT TRUNCATED AT 250 WORDS)

Cardiomegaly↗

PubMed1995

[Lactate acidosis: a rare or common disease?].

The authors present a survey of 50 documented cases of metabolic lactic acidosis (MLAC) recorded in the course of 5 years. To this study cases of severe hyperlactataemia (determined minimum lactate level of concentration 4 mmol/l) have been included. The sample consists of patients hospitalized at the Department of Internal Medicine Litomĕrice (hinterland of about 110,000 inhabitants). Liver involvement in 5 cases, cardiogenous shock in 6 cases, sepsis in 2 cases were the cause of lactic acidosis. The administration of biguanids (Adebit, Silubin R, Diformin) seems to be the probable cause in 21 cases, other cases were triggered by rarer causes. Dehydratation (16), vomiting (9), diarrhoea (11) dominate often in the clinical picture. The patients were admitted to the hospital often unconscious, with diagnose of vasculo-cerebral incidence, transitory ischaemic incidence... Quit rarely the typical Kussmaul's respiratory (only 9 cases) was recorded. Hyperlactatemia was usually associated with decrease of blood pH (theta = 7.12, pH less than 7.35 was recorded in 49 cases, pH less than 6.8 in 5 cases) and with decrease of BE value (= Ccoase, theta = -15.3 mmol/l). When the hypochloremia and/or hypocapnia was simultaneously more severe, only in these cases the value of pH was within physiological limits or even increased (10). The conclusions show that MLAC is not a rare disorder, however, its occurrence is depended rather on the clinician's capacity to diagnose this disorder and to indicate lactate examination. Usual signs of acidosis (Kussmaul's respiratory, decrease of pH, decrease of BE) can be missing in many cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Acidosis, Lactic↗

PubMedDate not supplied

[Surgical approach to the dorsal section of the liver].

The dorsal sector of the liver is a deep and posterior territory which lies behind the hilum, close to the inferior vena cava, beneath a plane passing by the terminal portion of the main hepatic veins. Two segments may be distinguished. A left one, segment I, the prominent part of which is the caudate lobe, is united anteriorly with segment IV and lies to the left of the vena cava. A right one, segment IX, is posterior to the right portal pedicle, anterior to the vena cava (at times also to the right), beneath the terminal portion of the right superior and the middle hepatic veins. This dorsal sector is supplied by numerous small ascending portal branches of 1st, IInd and IIIrd order, and efferent veins enter directly the caval stem. The sector lies in the posterior surface of the liver, covered by the mass of the organ and the lesser omentum, fixed posteriorly by the coronary ligament and the entrance of the hepatic veins into the vena cava. However there is always a loose connective tissue between the liver and the vein. Three manoeuvres give access to this dorsal territory: 1. Posterior detachment of the liver by division of the lesser omentum, the falciform and coronary ligaments; the vena cava is then well exposed.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗

PubMed1993

[Lyme borreliosis: review of present knowledge].

The author reviews hitherto assembled knowledge on a bacterial disease, Lyme borreliosis transmitted by ticks. Initial information on Lyme borreliosis appeared at the beginning of the 20th century. In Czechoslovakia attention to the disease was paid since cca 1960. The infection occurs as a rule in the summer months during the period when ticks are parasitic and at that time the causal agent of the disease is transmitted to hosts. Information on the prevalence and incidence of Lyme borreliosis in Europe is not complete and so far we do not possess a standardized diagnostic method for assessment of circulating antibodies in the patients' serum and cerebrospinal fluid. The infectious disease is caused by the gram-negative spirochete Borrelia burgdorferi. The Borrelia cell has a similar morphological structure as cells of other gram-negative bacteria. Chemical analysis of the external membrane of B. burgdorferi revealed the presence of 46% proteins, 51% lipids and 3% carbohydrates. The typical shape of borrelias indicates marked ondulation of 8-14 periplasmatic flagellae along the cell body. Borrelias can be cultivated in vitro in modified Barbour-Stoenner-Kelly medium at an optimal temperature of 30-37 degrees C. The change of morphology during cultivation is typical for B. burgdorferi. Clinically Lyme borreliosis is manifested in two stages. A typical manifestation of the early stage is a skin lesion--erythema migrans. The later stage is characterized above all by relapsing arthritis, CNS infection and chronic acrodermatitis chronica atrophicans. The disease is treated by administration of a number of antibiotics either by the oral route or by injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗

PubMed1993

[Silent myocardial ischemia. Status in 1992].

Silent myocardial ischaemia is found in 5% of a completely symptom-free population, in 30% of patients with a history of myocardial infarction and in 60 to 100% of patients with stable or unstable angina pectoris. Only one fifth to one quarter of episodes of myocardial ischaemia is associated with angina pectoris which means that 75% to 80% of episodes take a silent course. Episodes of myocardial ischaemia take place at lower heart rates than during exercise test and they are induced by common, everyday activities of the patient. So far it is not known why some episodes of myocardial ischaemia are silent while others are associated with angina pectoris. No differences were found in the duration or extent between silent or symptomatic myocardial ischaemia. Patients with frequent episodes of silent myocardial ischaemia have in general an elevated threshold of pain perception. A certain role is probably also played by the increased secretion of endogenous opioids--endorphins. The finding of myocardial ischaemia during ambulatory monitoring of ECG is of prognostic value regardless whether ischaemia is associated with angina pectoris. This applies in patients with unstable angina pectoris where ST depressions may be found during Holter monitoring of the ECG even when pain is controlled by treatment, and this finding is associated with more serious coronarographic findings and a poorer prognosis. The position is similar in patients with stable angina pectoris where episodes of depression of the ST segment during ambulatory ECG monitoring are associated with a poorer prognosis and this finding does not depend on the result of the electrocardiographic exercise test.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗

PubMedDate not supplied

[Types of medical lasers].

The knowledge about different types of lasers and their potential use in medicine is presented. A very rapid development of laser technology in the world imposes a need for up-to-date information about the characteristics of different laser instruments. Without this kind of information it would be difficult to keep in touch with the latest developments in the world's technology. Different types of lasers have different indication range in the medical practice. An inquiry into the fundamental principles of lasers physics is an important prerequisite for successful application of this technology in medicine. Laser as a surgical knife has shown certain advantages over scalpel, electrocautery and cryosurgery, as the laser surgery is a noncontact method, bloodless, precise, with better visualization, minimal postoperative edema, painless healing, without complications. Although laser cannot entirely replace conventional surgical instruments, it is still the instrument of choice for treatment of numerous pathological conditions. The carbon dioxide laser is a highly precise, bloodless light scalpel used for incising and excising tissues and sealing small blood vessels. The infrared beam at 10,600 nm wavelength is absorbed by water and tissue destruction is due to the instantaneous vaporization at relatively low temperature of 100 degrees C. The beam seals blood vessels of up to 0.5 mm in diameter and if the beam is defocused, larger vessels may be controlled. The beam also seals lymphatics, possibly reducing the spread of tumour cells by this route, and seals nerve endings: there is no incidence of neuroma formation. Carbon dioxide laser has shown a great efficiency in otorhinolaryngology, in maxillo-facial surgery and plastic surgery, in urology and gynecology. Provides true "no touch" surgery, and is used increasingly in neurosurgery for the precise atraumatic removal of tissue and for creation of precise lesions for the control of pain. The carbon dioxide laser beam cannot, at present, be transmitted via a flexible fibre, although a number of fibres are being investigated. Delivery of laser energy to microscope, colposcope or handpiece is via an articulated arm which is a hollow tube with mirrors at the articulations. The argon laser produces blue-green coherent light at a number of wavelengts but 80% of the energy is at wavelengths of 488 and 514 nm. This laser was first used in ophtalmology to treat diabetic retinopathy through, and without damage to, the clear anterior parts of the eye. The argon laser is used for blood vessel coagulation but can be used to perform slow, thermal tissue destruction at higher power levels. Argon laser is most commonly used in ophthalmology for otological micro-surgery, particularly in the treatment of otosclerosis and tympanosclerosis. Very good results have been achieved in the argon laser treatment of gastrointestinal bleeding ulcers, vascular lesions and polyps. Dermatology is another field where argon laser has shown great efficiency: hemangyomas, telangiectasias, tattoos, small benign and malignant tumours are amenable to argon laser treatment. In neurosurgery it is used to control both normal and abnormal blood vessels but at present much work on treatment of arteriovenous malformations and aneurysms is experimental. Both the argon laser energy can be transmitted via flexible fibre optic delivery system which can then be attached to an operating microscope, slit lamp, endoscope delivery fibre or handpiece. The Neodymium-YAG laser is used both for tissue destruction with good haemostasis and for the control of normal and abnormal blood vessels. This laser produces infrared coherent light at 1060 nm wavelength, which is deeply absorbed in the tissues without colour or tissue specificity. Neodymium-YAG laser is mostly used in tracheobronchial, gastrointestinal and urologic pathology in the treatment of stenoses, granulomas, benign tumours, and for reduction of malignant tumours. (ABSTRACT TRUN

Laser Therapy↗

PubMed1984

[Recent developments in medical law].

The most spectacular aspect is the extremely rapid expansion of medical law. Even if there is a close connection between developments in medicine and in law, the question must be asked as to what extent new discoveries and advances in medicine play a dominant role here, and to what extent the emphasis is on the further development of law. How advances in medicine can give rise to new legal problems was most impressively demonstrated some time ago by the discussion about cerebral death. In view of the progress made in the field of re-animation and intensive care, the current question is whether or not the physician's duties and rights to maintain life should be limited in hopeless cases when patients are incapable of making decisions themselves. This is demonstrated in particular by the discussion about the binding character of "patient testaments" in which healthy subjects declare that they do not want treatment under such circumstances. The decisive factor will continue to be the presumptive will of the patient at the respective time, and this will have to be ascertained considering all circumstances prevailing at that time. New questions with regard to the ethical and legal limitation of the technically feasible also arise from the possibility of culturing embryos from legal abortions or extracorporally fertilized ova to obtain transplants, and from the possibility of implanting extracorporally fertilized ova into the uterus, perhaps that of a "hired childbearing wet-nurse." In addition to ethical and legal problems, questions of parentage would arise here similar to those already of current interest in connection with artificial heterologous insemination. For physicians practicing these methods, questions concerning liability and the limitation of professional secrecy vis-à-vis the semen donor might become the issue of law suits in the near future. Current problems of "unsuccessful sterilization" and nonperformance of an abortion through the physician's fault although abortion was indicated for eugenic reasons are, on the other hand, primarily due to the fact that the law--possibility even for acceptable reasons--establishes legal obligations for the physician which, in the last analysis, aim at preventing human life from coming into being.(ABSTRACT TRUNCATED AT 400 WORDS)

Germany, West↗

PubMedDate not supplied

[Drug-resistant malaria: problems with its definition and technical approaches].

In antimalarial chemotherapy, drug resistance is defined as "the ability of a parasite strain to survive and/or multiply despite the administration and absorption of a drug in doses equal to or higher than those usually recommended but within the limits of tolerance of the subject". This official World Health Organization definition, based on clinical and parasitological observations, was established in 1973, when genetics, pharmacology and in vitro culture techniques were still in the early stages of development. Several techniques are currently used to detect drug-resistant Plasmodium falciparum. Several in vivo tests, the traditional gold standard for the detection of drug resistance, have been developed. Classical tests include the 28-day extended test and the 7-day test, interpreted using the S-RI-RII-RIII classification system (S for susceptible and R for resistant, with three degrees of resistance, I to III, depending on parasitological response). These tests cannot be applied in practice, in field situations, and the results do not take into account the clinical condition of the patient, largely because they were designed for use with asymptomatic carriers. These limitations led to the development in 1994 (modified in 1996) of the more practical and simplified 14-day test of therapeutic efficacy. This test classifies the patient's clinical and parasitological response as "adequate clinical response", "late treatment failure" or "early treatment failure". This in vivo test of therapeutic efficacy can be applied in the field with a minimum of health facilities, personnel and other resources. However, true cases of drug resistance may not always be detected by in vivo tests due to pharmacokinetic variations, reinfection, multiple infections, noncompliance or interference with the acquired immune response. The most commonly used reliable in vitro assay, the isotopic microtest, determines the drug concentration at which 50% of parasite growth is inhibited (50% inhibitory concentration IC50). The in vitro assay not only yields quantitative results, it also determines the phenotype of the parasite independently of the immune and physiopathological conditions of the host. However, this in vitro assay requires highly skilled personnel and laboratory equipment. In addition, parasites isolated from patients who have taken medication on their own initiative a few days before consultation usually do not grow in vitro and the interpretation of assay results for patients with multiple infections may be equivocal. One of the major problems with in vitro tests is the determination of the threshold IC50 values that distinguish susceptible from resistant parasites. There are currently no fully validated cut-off points for assessing in vitro resistance. Despite these shortcomings, in vitro tests are of value, particularly if performed in parallel with the in vivo test. Molecular biology has made a major contribution to our understanding of the mechanisms of drug resistance. Discrete point mutations in the genes encoding dihydrofolate reductase and dihydropteroate synthase are strongly associated with resistance in vitro to pyrimethamine and sulfadoxine, respectively. Preliminary results have also suggested that these mutations are responsible for the failure of sulfadoxine-pyrimethamine combination treatment. No causal relationship between discrete polymorphisms in the candidate genes and in vitro chloroquine resistance has yet been established. High-performance liquid chromatography is being increasingly used to determine the plasma concentrations of antimalarial drugs in patients with prophylactic or therapeutic failure, to check that the failure of the treatment is not due to inadequate levels of the drug in the patient. Taking into account all these aspects of resistance to antimalarial drugs we think that the WHO definition of drug resistance is now inadequate. (ABSTRACT TRUNCATED)

Antimalarials↗

PubMed2000

[Tuberculous infection and prevention].

In Japan, the number of tuberculosis infected patients has been increasing again, especially in the elderly. The incidence of newly registered tuberculosis patients who are over 70 years is 34%. The outbreak of tuberculosis also has been increasing, and has become a serious social problem. The elderly have a high risk of developing tuberculosis because of their immunosuppressed condition due to underlying disease and aging. Elderly active tuberculous people also confer a risk of tuberculosis infection to the non-tuberculosis infected young generation. In this symposium, we discussed about 1) the tuberculosis outbreak related to the strategy for tuberculous prevention, 2) the health examination to detect tuberculous people in the middle-aged and elderly, 3) the nosocomial transmission of tuberculosis in the hospital, 4) the nutritional damage and immunosuppressive state in elderly people related to developing active tuberculosis in latent tuberculous infection, and 5) the organ transplantation and tuberculosis focusing on living related liver transplantation. Seven cases of tuberculosis outbreak were reported in Osaka from 1989 to 1998, 2 cases in the hospital and 5 in others. Tuberculous infection index (maximum sputum Gaffky score multiplied by the number of months of persisted cough) was 8 and 15 in the hospital, 3, 0, 84, 14, and 27 in others. Three cases (43%) were observed in persons with less than 10 of this index. It is essential to evaluate carefully for tuberculosis outbreak in extraordinary examination, if the tuberculous infectious index is low. There are various immunosuppressive patients with malignancy and other underlying disease in the hospital, so we have to pay careful attention for tuberculous outbreak when there is an active tuberculous patient. In these seven cases of extraordinary examination for tuberculous epidemic, only one (0.4%) of 241 cases who received isoniazide prophylactic therapy developed active tuberculosis. Isoniazide prophylactic therapy was an important strategy for the prevention of tuberculous outbreak. (Isamu TAKAMATSU, Osaka Prefectural Habikino Hospital, Osaka). It is essential to prevent tuberculosis in the elderly to achieve tuberculosis control in public health. The health examination was an important strategy for the detection of tuberculosis in the middle-aged and elderly. The incidence of tuberculosis detection is only 9.3% by the health examination at this age. However, the health examination has well detected active tuberculosis patients in elderly (34.5%), and also 16.8% in smear positive cases with pulmonary cavitary formation. The early detection of persons with active tuberculosis is essential, and further discussion regarding cost-performance and accuracy of the health examination for tuberculosis should also be essential. Prophylactic therapy of isoniazide also might be considered for the high risk middle-aged and elderly people with underlying diseases. (Masako OMORI et al., Research Institute of Tuberculosis, Japan Anti-Tuberculosis Association, Tokyo). The cases of nosocomial transmission of tuberculosis in the hospital have been increasing. In younger persons, the incidence of tuberculosis infected nurses and doctors is relatively higher than healthy control. The transmission of tuberculosis from elder active tuberculosis patients to healthy non-tuberculosis infected medical workers has been well recognized. It is very essential to follow guidelines for the prevention of tuberculous transmission in the hospital from the Japan Tuberculosis Society including routine tuberculin skin test for fresh medical workers. Primary education for tuberculosis in medical and nursing school is also an important strategy. Further discussion might be essential that BCG could prevent tuberculosis transmission in tuberculin skin test negative adults. (ABSTRACT TRUNCATED)

Adult↗

PubMed1990

[Dissemination of arboviruses transmitted by mosquitoes in Czechoslovakia and the epidemiologic consequences].

In Czechoslovakia three new arboviruses isolated from mosquitoes were discovered--Tahyna, Calovo and Lednice--which circulate on our territory. The submitted paper summarizes the results of long-term oecological studies of these viruses, in particular their vectors and hosts. The differences between individual viruses in this respect are very marked and from them also differences in the circulation of these viruses follow. There are also very marked differences in their distribution, as apparent from the isolation of 83 strains of the viruses from more than 263,000 mosquitoes 61 of whom belong to the Tahyna virus, 15 to the Calovo virus and 7 to the Lednice virus. The Tahyna virus was isolated from 8 mosquito species, virus Calovo and Lednice only from a single one. While vectors of the Tahyna virus, mainly from the genus Aedes, are widespread as far as biotypes, radius of action and hosts are concerned, and they attack man, vectors of the Calovo and Lednice virus--Anopheles maculipennis s.l. and Culex modestus--have much more restricted activities as regards biotype, radius of action, hosts and contact with humans. The above reasons explain also the high prevalence of antibodies against the Tahyna virus in the population living in the natural focus of this virus and the relatively high number of diseases, in particular in children, where every seventh influenza--like case and every fifth case with manifestations of meningoencephalitis can be ascribed to this virus. The low prevalence of antibodies the Calovo virus in humans is explained by the marked zoophilia of vectors of this virus.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1991

[Consciousness functions in psychoses. Concepts, empirism and hypotheses].

Schizophrenia may be described as a disease where speech, bodily language and social responsiveness are obvious expressions of a deteriorated ability to interact with the surroundings in a precise and relevant way. The lack of precision and relevance pertains to perception and recall as well as communication and action. The deficient potential for activation of the prefrontal cerebral cortex is a neurobiological correlate to the lesion of precise and relevant planning and expression. Impairment of formal thought and language in schizophrenia are suggested to result from a developmental disorder pertaining to language and concept formation (apperception). In reactive psychoses with dissociative disturbances of consciousness there is an inefficient capacity for adapting to external reality; thus relevant conscious planning and interaction with the outside world are impaired. Clinically a distractibility of a tematic nature ensues. Except for catastrophic events, psychotic reactions cannot be predicted from analysis of the actual experience--neither concerning the external nor the internal aspects of conscious awareness. Sometimes, however, previous events relating to the formation of the self may add explanatory value to the analysis of reactive psychosis. In some cases biological predisposition is the decisive determinant. The normal discrimination between sense-perception and imagination has a counterpart in the dichotomy of awareness of the outside world versus awareness of the self. The following are examples of psychotic experience where the normal ability for dichotomic discrimination may be damaged: Illusions of affect, hallucinations, Schneider's first rank symptoms, "Anwesenheit" and consciousness of time.(ABSTRACT TRUNCATED AT 250 WORDS)

Consciousness↗

PubMed1991

[Astigmatism in corneal graft. Prevention and treatment].

The tremendous development of the photokeratoscope and corneal topography analysis explains the development of corneal astigmatism study in corneal graft. Our study consists in a review of the bibliography. The prevention of the astigmatism needs the following: before the trephination, the astigmatism has to be treated (correction of against the rule astigmatism which is usual in the aphake people); during the trephination, to minimize the deformation of the eye ball, to choose a good diameter for the keratoconus case, to use a pneumatic trephine in order to have a perpendicular cut (the use of the laser Excimer seams promising); The suture of the corneal graft can be done with a double running suture 10/0 and 11/0. The 10/0 is removed at the third month, the visual recovery is faster but the average astigmatism is not as good as with the interrupted 10/0 sutures and running suture 11/0. This technique is good for an old patient or a one eyed people specially interested in a faster recovery of visual acuity. The second possibility is to use 16 interrupted sutures with and 11/0 running suture. With this technique, the sutures are removed selectively depending on the keratometry and the photokeratoscopy. The visual recovery is longer but the astigmatism at the end is very low. When all the sutures have been removed, the residual astigmatism can be treated when there is not any misalignement between the cornea and the graft. The keratometry, photokeratoscopy allows to find the meridian which is abnormal and to find out if the astigmatism is symmetrical or asymmetrical. The astigmatism is symmetrical if the deformation is the same at either side of the meridian. When the abnormal meridian is the steepest, the only thing to do is a relaxing incision (one or two if is asymmetric, two if the astigmatism is symmetric). The size of the relaxing incision is determined by the photokeratoscopy and the deepness by the effect obtained during surgery looking at a qualitative keratometer. On the table, the effect must be about 50% of over correction. When, the abnormal meridian is the flattest, the only thing to do is a wedge resection (if the astigmatism is asymmetric) or two wedge resections (if the astigmatism is symmetric). The size of the cuneiform resection is choosen with photokeratoscopy. The study of the literature about the Ruiz incision adapted to corneal graft cannot nowadays conclude to the accuracy and safety of this technique.(ABSTRACT TRUNCATED AT 400 WORDS)

Astigmatism↗