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Toward a new model of treatment of homosexuality: a review.

A review of the literature of outcome studies in the psychoanalytic or behavioral treatment of homosexuality reveals limited results when "heterosexual shift" is the goal. Recently, however, a growing body of empirical knowledge has accumulated that challenges the illness or maladaptive model of homosexuality. Consequently, a new model has been emerging that is designed to assist homosexuals to recognize, accept, and value their sexual identity and to help them adjust to this identity in a predominantly heterosexual society. Unfortunatley, only a few studies exist that examine the result of this new approach.

Adult↗

Linking research and innovative clinical practice: the story of diabetes mellitus.

Research into diabetes mellitus and the clinical practice of diabetology are a fascinating illustration how the accumulation of knowledge leads to changing scientific theories and paradigms. The pivotal point in the history of diabetes, the discovery of insulin and its introduction to treatment, was one of the most spectacular events in medicine. Later, diabetes care provided, among other developments, models for multidisciplinary approach to treatment and the blueprint for community-based epidemiological studies. The history of diabetology also illustrates the role of chemistry, and later laboratory medicine, in the management of disease. This article is an introduction to the special issue of Clinical Chemistry and Laboratory Medicine, focused on diabetes mellitus and its complications.

Diabetes Mellitus↗

Remyelinating and neuroprotective treatments in multiple sclerosis.

Multiple sclerosis (MS) is the most common cause of neurological disability in young adults. The pathological hallmark is multifocal demyelination and inflammation in the CNS. In addition, there is also a variable extent of axonal damage. Remyelination has been seen in up to 70% of lesions but repair is generally incomplete. The demonstration of neuropathological heterogeneity of MS lesions suggests different pathophysiological subtypes and it is therefore unlikely that there is a uniform cause of incomplete remyelination in MS. In recent years, a great body of knowledge has accumulated in order to better understand the regulatory mechanisms of remyelination. This has led to a number of approaches to promote repair mechanisms, most of which have been successful in animal experiments. Unfortunately, the translation of these experimental data into clinical treatments has proven difficult. More information on the pathogenesis of MS, the reason why repair mechanisms fail in MS and a better understanding of the regulation of remyelination are required. This will ultimately lead to a specific treatment tailored for the individual patient and will probably involve a combination of immunomodulation, remyelination and neuroprotection.

Animals↗

Selective oestrogen receptor modulators--current and future brain and behaviour applications.

Selective oestrogen receptor modulators (SERMs) are compounds that act as oestrogen agonists on selected targets while being oestrogen antagonists on others. The main targets of SERMs are oestrogen agonist activity on bone metabolism and several functions of the cardiovascular system, as well as oestrogen antagonism in the breast and uterus. They are indicated for the treatment and/or prevention of breast and endometrial cancer, osteoporosis and coronary heart disease. The extensive documentation of the multiple oestrogen effects on the CNS, greater understanding of the mechanisms of action, and especially the discovery of a second oestrogen receptor with differentiated distribution and mechanisms, have all led the way to the possibility of specific CNS-targeted SERMs. The demonstration that oestrogen selectively improves cognition, delays the appearance of Alzheimer's dementia, improves the feeling of well-being, as well as the response to antidepressant medications, provides targeted CNS indications for SERMs. The CNS effects of the currently marketed SERMs are not sufficiently explored yet. However, in postmenopausal women, tamoxifen and raloxifene probably show the most oestrogen agonist CNS effects. In women of reproductive age, competition with oestrogen probably exists, resulting in antagonist effects. Activity in men is still mostly unknown. It is quite safe to predict that the recent accumulation of knowledge, combined with the large, thirsty anticipated market for these 'designer oestrogens', will lead to clinical trials of CNS-targeted SERMs in the very near future.

Behavior↗

Hypothalamic hamartoma.

The incidence of hypothalamic hamartomas (HHs) has increased since the introduction of magnetic resonance (MR) imaging. The etiology of this anomaly and the pathogenesis of its peculiar symptoms remain unclear, but recent electrophysiological, neuroimaging, and clinical studies have yielded important data. Categorizing HHs by the degree of hypothalamic involvement has contributed to the accurate prediction of their prognosis and to improved treatment strategies. Rather than undergoing corticectomy, HH patients with medically intractable seizures are now treated with surgery that targets the HH per se, e.g. HH removal, disconnection from the hypothalamus, stereotactic irradiation, and radiofrequency lesioning. Although surgical intervention carries risks, total eradication or disconnection of the lesion leads to cessation or reduction of seizures and improves the cognitive and behavioral status of these patients. Precocious puberty in HH patients is safely controlled by long-acting gonadotropin-releasing hormone agonists. The accumulation of knowledge regarding the pathogenesis of symptoms and the development of safe, effective treatment modalities may lead to earlier intervention in young HH patients and prevent the decline in their cognitive abilities and quality of life. This review of hypothalamic hamartomas presents current classifications, pathophysiologies, and treatment modalities.

Hamartoma↗

The role of gastrointestinal and neuronal peptides in the pathophysiology of diabetes mellitus.

The pancreatic islet hormone secretion is modulated by one or more gastrointestinal peptides ("gut-factor") secreted in response to various types of ingested nutrients. Among a number of postulated candidates for the putative "gut-factor", the gastric inhibitory polypeptide (GIP) has recently emerged as a most likely enteric signal of physiologic import, although its precise role in the pathophysiology of diabetes mellitus remains incompletely understood. During the past decade, an avalanche of knowledge has accumulated regarding a number of peptide agents common to the gastro-enteric-pancreatic system and the nervous system. Preliminary evidence indicates a potential role of several of these peptides in the pathophysiology of diabetes. For instance, cholecystokinin and human pancreatic polypeptide (hPP) may be importantly involved in the regulation of appetite and satiety control and the development of obesity whereas somatostatin, "endorphins", and neurotensin may directly or indirectly modulate islet hormone secretion. Finally the significance of the recently demonstrated presence of insulin and glucagon or glicentin-like peptides in the brain requires close scrutiny.

Animals↗

A microcomputer-photocell system to monitor periparturient activity of sows and transfer data to remote location.

A microcomputer-photocell system to record, summarize and transfer data on the postural changes of crate-confined sows was developed. The system uses an infrared photocell system mounted on farrowing crates to detect changes in sow body postures prior to parturition. When a sow breaks the infrared beam by standing or sitting, the lack of reflection back to the photocell activates a relay. The relays are connected to an input/output card inside the primary ("host") microcomputer. A second microcomputer, at a location remote to the animal facility, and the host computer both are equipped with multi-tasking operating systems. The host computer uses a data acquisition program written in BASIC to record posture changes, the sow's identifying number, date and time. Both computers are equipped with communications software so that the host computer can transfer data to the remove location while continuing to collect data. Either computer can be used to summarize, graph and examine the accumulated data. Knowledge of periparturient activity patterns allows the observer to predict farrowing time and to determine whether farrowing has begun without being present in the farrowing facility.

Animals↗

Endothelins in chronic liver disease.

This review describes recent progress in the accumulation of knowledge about the endothelins (ETs), a family of vasoactive 21-amino acid polypeptides, in chronic liver disease. Particular prominence is given to the dynamics of ET-1 and ET-3 and their possible relation to the disturbed circulation and neurohumoral dysregulation found in cirrhosis. Recent studies have shown that the ET system is highly activated in most cirrhotic patients. Circulating ET-1 and ET-3 levels have a positive relation to the severity of the disease and fluid retention, with the highest values recorded in patients with functional renal failure. Studies on liver biopsies have revealed synthesis of ET-1 in hepatic endothelial and other cells, and recent investigations have identified the hepatosplanchnic system as a major source of ET-1 and ET-3 spillover into the circulation, with a direct relation to portal venous hypertension. In addition, marked associations with disturbance of systemic haemodynamics and with abnormal distribution of blood volume have been reported. Although the pathophysiological importance of the ET system in chronic liver disease is not completely understood, similarities to other vasopressive and antinatriuretic regulatory systems (i.e. the sympathetic nervous system, renin-angiotensin-aldosterone and vasopressin) are apparent, with respect to kinetics and haemodynamic dysregulation. Cirrhosis seems to be a pathophysiological condition with indications of the occurrence of ETs, not only as local modulators, but also as a system with potential importance for systemic regulation.

Animals↗

Hearing in the elderly > or = 80 years of age. Prevalence of problems and sensitivity.

This article is part of an epidemiological study on hearing in an urban population > or = 80 years of age, and concentrates on the prevalence of hearing problems and hearing sensitivity as a function of age and gender. Prior to the study, 2915 residents aged 80+ from the Valby area in Copenhagen were selected for investigation and subdivided into two groups. The first group, comprising n = 859 subjects previously provided with HA, and the second group, resulting from an invitation mailed to n = 565 subjects, were matched according to the age and gender distribution of the population, i.e. 24% males and 76% females. Among these, only 41% at a median age of 84 years, range 80-96, accepted the invitation, being significantly younger than the non-attenders. The estimated prevalence of self, reported hearing problems ranged between 33 and 66%, increasing with increasing age. Significant differences were found in the hearing sensitivity as a function of gender, i.e. the hearing in the low-frequency area < 1 kHz is better, whereas the hearing sensitivity at > 2 kHz is significantly worse in males compared with females. The speech recognition score (SRS) was significantly higher in females compared with males, and a comparison between ears supports the finding that the right ear speech recognition score is better than the left. The study demonstrates the difficulties in obtaining reliable epidemiological data on the hearing in the elderly > or = 80 years, which represents an obstacle for the planning of appropriate hearing health services directed towards this age group, and collaborative studies are suggested in order to accumulate more knowledge.

Aged↗

The interface between epidemiology and molecular biology in the search for the causes of insulin-dependent diabetes mellitus.

Epidemiological techniques have been utilized to accumulate new knowledge about insulin-dependent diabetes mellitus (IDDM), leading to important insights into the disease process and the alteration of these mechanisms when viewed from a geographic or population base. More recently, highly powerful and sophisticated techniques of molecular biology have been added to the research arsenal, extending the knowledge on the genetic basis for IDDM and the probable environmental factors involved. The development and growth of the new discipline of epidemiological genetics promises exciting new developments for the future of our field as well as that of other major medical problems having a genetic base, but significantly influenced by environmental factors. This review stresses the importance of carefully validated diabetes registries in the study of the epidemiology of IDDM. The Children's Hospital of Pittsburgh and the University of Pittsburgh Medical Center have spear-headed the development of such registries, worldwide. The first international meeting on IDDM epidemiology in 1983 gave as a result, i.e., the finding that there were truly remarkable differences in the risk of developing IDDM depending upon the geographic location of the individual. Later collaborative work via the Diabetes Epidemiology Research International (DERI) group has confirmed the previous finding and added the description of secular trends and epidemics of IDDM. It is remarkable that the incidence rate of IDDM in children below 15 years vary from 1/100,000/yr in the Orient to 35/100,000/yr in Finland. The epidemiological approach in the study of IDDM has also stimulated research into the various facets of the etiology of the disease, genetic factors, autoimmune mechanisms and environmental factors.(ABSTRACT TRUNCATED AT 250 WORDS)

Autoantibodies↗

Revealing hidden relationships among yeast genes involved in chromosome segregation using systematic synthetic lethal and synthetic dosage lethal screens.

The vast accumulation of knowledge from genome sequencing projects and studies with model organisms has presented a remarkable challenge to biologists: to understand the functions of thousands of highly conserved genes and how they work together to regulate fundamental cellular processes. This challenge is compounded by the inescapable reality that most genes are 'buffered' by other genes that contribute to the same biological processes, limiting the impact of phenotypic studies with single mutants. In budding yeast, functional genomic methods have been developed for the systematic application of established genetic techniques. In particular, the Synthetic Genetic Array (SGA) method allows genome-wide synthetic lethal (SL) and synthetic dosage lethal (SDL) screens thus enabling an unbiased survey of genetic interactions. We have used genes encoding components of the yeast kinetochore as a biological testbed for assaying the utility of SGA-based SL and SDL screens for revealing new pathways and genes involved in chromosome segregation. We identified 211 nonessential deletion mutants that were unable to tolerate either overexpression or loss of function of kinetochore genes. Our study uncovered a wealth of relationships between gene products that functionally interact with the kinetochore, and also highlighted the value of performing genome-wide screens with both hypomorphic and hypermorphic alleles of query genes. Here, we will highlight our recent kinetochore SGA genomic screens, in the broader context of applying complementary genetic screening approaches in the systematic exploration of biological pathways or functional complexes.

Cell Division↗

Immunopathogenesis of the acquired immunodeficiency syndrome.

Many abnormalities of humoral and cellular immunity associated with the acquired immunodeficiency syndrome can be explained by the preferential infection of the T4 lymphocyte subset with the etiologic retrovirus. Severe alterations in specific T4 functions, such as inadequate immune responsiveness to specific antigen, result in devastating morbidity and mortality. On the basis of accumulated scientific knowledge, we outline the immunopathogenesis of this syndrome.

Acquired Immunodeficiency Syndrome↗

[Present status of basic studies and development of DNA vaccines].

Inoculation with plasmid DNA encoding immunogenic proteins of microorganisms induces specific antibodies and cytotoxic T lymphocytes. This method, termed DNA immunization, can provides protective immunity against viruses, bacteria and parasites in animal models. However, the mechanisms by which DNA vaccines induce immunity are not completely understood. Phase 1 studies of DNA vaccines in humans seem to have promising results, although the question about safety of DNA vaccine has not been confirmed yet. DNA vaccines have some advantages over currently used vaccines: inactivated and live attenuated vaccines. New knowledge is accumulating day by day. This approach may provide a new type of vaccines against various microorganisms in the near future.

Animals↗

[Detection of TTV DNA in hepatocellular carcinoma].

A new hepatitis agent, TTV has been cloned from post-transfusion hepatitis patient sera. This virus has a single stranded DNA as genome, surrounded by viral capsid antigen without envelope. It might be a member of parvoviridae. But genome organization is far from the known parvoviridae such as B19 and adeno-associated virus. Although this virus could be a new causative agent for nonA-nonG hepatitis, high healthy carrier rate, no relation with hepatocellular carcinoma and no evidence of amplification in parencymal hepatocyte might lead to less importance in liver disease. It is necessary to accumulate further knowledge about this new agent for the coming transplantation medicine.

Base Sequence↗

[Participation of transcriptional factors in the regulation of lymphocyte differentiation].

The cytomorphological changes as well as the expression of certain markers in the different stages of lymphocyte differentiation are well known. Studies carried out on expression patterns of specific genes in lymphoid cells and their regulatory mechanism have led to the identification of the fundamental mechanism of cell development and activation. A great deal of knowledge has accumulated concerning enhancers and promoters, the regulatory elements of those genes and the transcriptional factors to which they bind. The present paper analyzes these components and the participation of some of them such as PU.1, Ikaros, Aiolos, GATA-3, Egf-1, E2A, EBF-1, PAX-5 (BSAP), TFE-3, Oct-1, Oct-2, and Nf-kappa B in the regulation of the differentiation stages of cells belonging to the B and T lymphoid lineages.

Animals↗

[Depression scale for research in and identification of postpartum depression].

Postpartum depression (PPD) is a relatively frequent and serious condition, with negative consequences for the mother, her infant, and the family. From research and clinical experience in many countries, it has been found that PPD can be identified early, and women at risk for developing PPD can be identified before delivery in the framework of primary health care service. The Edinburgh Postnatal Depression Scale (EPDS) has been found valid for this purpose, both in the original English version, and in translation to numerous languages. The Hebrew translation of the EPDS is presented, and it is recommended that Israeli researchers use the same translation to facilitate accumulation of knowledge regarding the epidemiology of PPD and intervention strategies in various Israeli population groups, and for comparison with data from other countries.

Depression, Postpartum↗

Preliminary results of examinations of rats after a 22-day flight aboard the Cosmos-605 biosatellite.

The results of biomedical investigations carried out in flights of the Salyut and Skylab orbital stations give evidence that during prolonged weightlessness cosmonauts and astronauts remain in a good physical and mental condition. They fill specialists with optimism in regards to a further increase of the duration of manned space flights. In order to make reliable plans for such missions, it is necessary to accumulate detailed knowledge about the mechanism of the effect of weightlessness on different functions of the human body. In addition to manned experiments, of great interest are animal experiments. They may yield data that cannot be obtained in human studies, which is obviously very important from the point of view of space medicine. This was the purpose of the experiment carried out in November 1973 on the biosatellite Cosmos-605; 45 rats aboard the biosatellite flew for 22 d. Preliminary results of examinations of rats after a 22-d space flight in the Cosmos-605 satellite demonstrated not only physiological and biochemical but also morphological changes in the animal body due to prolonged weightlessness. These changes were reversible.

Aerospace Medicine↗

[History, principles of construction of combined vaccine and problems of vaccine prophylaxis with their use].

This problem article deals with modern trends in the creation and use of combined vaccines, the advantage and drawbacks of multicomponent preparations. The data on competition, interference and synergism in the action of individual components making up combined vaccines, on the cellular and molecular mechanisms of the interaction of antigens are presented. Specific features of the development of immunity induced by complex vaccines with due regard to the action of genetic and phenotypic signs, as well as the formation of humoral and cell-mediated immunity. The priority of Russian researchers in the development of the first combined vaccines is pointed out. On the basis of theoretical knowledge and accumulated practical experience the main principles of the construction and properties of combined vaccines have been formulated.

Humans↗