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PubMed1983

Mental health in the Third World.

In spite of great national and international efforts and relative success in achieving technological and economic progress, the underlying situation in the Third World offers little cause for optimism. Some notable exceptions notwithstanding, in most countries poverty is increasing at an alarming rate, with its accompanying misery, poor health, and social unrest. Unequal distribution of material wealth, political instability, and the crumbling of traditional and cultural values are also increasingly prevalent. Critical assessment of the philosophy, goals, and methodology of development is an urgent requirement in many nations. Mental health endeavors in the Third World need similar reformulation of both immediate and long range objectives and methods, if ever-increasing mental health demands fostered by such rapid and sweeping changes are to be met. Four major models--the hospital-based model, the medical school-based model, the community-based model, and the voluntary organization model--have so far been the basis for mental health development in Third World nations and, to a certain extent, have produced the needed personnel and services. A fifth model--the primary health care model--seems to hold more promise for the future. By virtue of its integration with general health and other administrative social networks, it can more easily reach out to the community, providing both curative and preventive mental health. Whichever model or combination of models any one nation or region adopts, future mental health endeavors in the Third World should be an integral part of overall social policy and health planning. Taking children, family, and school as major foci, such efforts are indispensible and should constitute a positive force in shaping the continuing process of social evolution.

Community Mental Health Services↗
PubMedDate not supplied

Aneurysmal bone cysts of the pelvis in children: a multicenter study and literature review.

The authors analyzed a series of 15 pelvic aneurysmal bone cysts (9 boys and 6 girls) in children and adolescents who were reviewed with an average follow-up of 50.3 months. Pain and limp were the main symptoms. Four patients had no treatment after the open biopsy. Eleven patients were treated with curettage. Preoperative selective arterial embolization was performed in three cases before curettage. Two recurrences were noted after curettage; recurrences were treated successfully with further curettage. As a result, the authors recommend curettage; more aggressive operative intervention does not appear to be indicated. No major intraoperative vascular complications occurred. Spontaneous healing in a few cases (even in active or aggressive lesions) argues for clinical and radiologic observation after biopsy when possible. In case of a propitious evolution, observation must be continued and surgery might be avoided, but if the lesion increases, treatment must be proposed.

Adolescent↗
PubMed2002

Structure and phase transitions of LiTaOGeO(4).

The structure of LiTaOGeO(4) has been refined using X-ray diffraction data collected at 293 K and at 173 K. The low-temperature structure is isostructural with LiTaOSiO(4) and closely related to the low-temperature structure of titanite, CaTiOSiO(4). Li occurs in a distorted tetrahedral coordination. The transition to the disordered structure, with space group symmetry C2/c, occurs at T(c) = 231 (1) K. Li is disordered across two symmetry-equivalent positions and Ta is located at the centre of its coordination octahedron in this paraphase. The transition is continuous, and the thermal evolution of the order parameter is well approximated using a tricritical mean-field model. Anharmonic thermal displacement of the Li cation has been analyzed and its one-particle potential has been determined. The height of the potential barrier separating the two Li positions across a curved trajectory is close to RT(c), where R is the universal gas constant.

Journal Article↗
PubMed1976

Conditioning afterimages: a procedure minimizing the extinction effect of normal test trials.

Six subjects were trained on a conditioning schedule of ten trials a day for 25 days: a further 18 CS-US pairings were presented on 4 subsequent days. The tone employed as the CS was put on 30 sec before the presentation of a briefly illuminated visual target (the US) and maintained until terminated by the subject when his afterimages disappeared. This procedure allowed continuous monitoring of the evolution of the conditioned response (conditioned afterimages): directly for CRs with a latency of less than 30 sec which could occur on every training trial before the US was presented; indirectly from the changes in the duration of afterimagery following the presentation of the US. As every trial yielded some evidence about the evolution of the CR, unreinforced test trials were not necessary after every block of training trials so minimizing the extinction effect attributable to the presentation of an unreinforced CS. In the course of the experiment the mean duration of afterimagery increased almost fivefold with one subject showing a tenfold increase. Five of the subjects experienced visual images in response to the tone alone and were judged to be conditioned. The data are discussed in relation to the evolving levels of conditioning identified by Bzhalava (1958, 1965).

Acoustic Stimulation↗
PubMed2000

Respiratory syncytial virus genetic and antigenic diversity.

Respiratory syncytial virus (RSV) is a major cause of viral lower respiratory tract infections among infants and young children in both developing and developed countries. There are two major antigenic groups of RSV, A and B, and additional antigenic variability occurs within the groups. The most extensive antigenic and genetic diversity is found in the attachment glycoprotein, G. During individual epidemic periods, viruses of both antigenic groups may cocirculate or viruses of one group may predominate. When there are consecutive annual epidemics in which the same group predominates, the dominant viruses are genetically different from year to year. The antigenic differences that occur among these viruses may contribute to the ability of RSV to establish reinfections throughout life. The differences between the two groups have led to vaccine development strategies that should provide protection against both antigenic groups. The ability to discern intergroup and intragroup differences has increased the power of epidemiologic investigations of RSV. Future studies should expand our understanding of the molecular evolution of RSV and continue to contribute to the process of vaccine development.

Adult↗
PubMed2004

Continued production of drug-sensitive human immunodeficiency virus type 1 in children on combination antiretroviral therapy who have undetectable viral loads.

Highly active antiretroviral therapy (HAART) can suppress plasma human immunodeficiency virus type 1 (HIV-1) levels to below the detection limit of ultrasensitive clinical assays. However, HIV-1 persists in cellular reservoirs, and in adults, persistent low-level viremia is detected with more sensitive assays. The nature of this viremia is poorly understood, and it is unclear whether viremia persists in children on HAART, particularly those who start therapy shortly after birth. We therefore developed a reverse transcriptase PCR (RT-PCR) assay that allows genotyping of HIV-1 protease even when viremia is present at levels as low as 5 copies of HIV-1 RNA/ml. We demonstrated that viremia persists in children with plasma virus levels below the limit of detection of clinical assays. Viremia was detected even in children who began HAART in early infancy and maintained such strong suppression of viremia that HIV-1-specific antibody responses were absent or minimal. The low-level plasma virus lacked protease inhibitor resistance mutations despite the frequent use of nelfinavir, which has a low mutational barrier to resistance. Protease sequences resembled those of viruses in the latent reservoir in resting CD4(+) T cells. Thus, in most children on HAART with clinically undetectable viremia, there is continued virus production without evolution of resistance in the protease gene.

Acute Disease↗
PubMed1987

Fever after acute myocardial infarction in patients treated with intravenous timolol or placebo.

Body temperature was studied in 65 patients admitted to hospital within four hours of the onset of symptoms of acute myocardial infarction. Thirty three patients had been randomly assigned to intravenous timolol treatment and 32 to placebo treatment. Infarct evolution was assessed by continuous vectorcardiography and creatine kinase release. Maximum and mean temperatures during the first eight days were significantly lower in the timolol group, who were discharged from hospital one day earlier. Eight patients in the placebo group had temperatures of greater than 39 degrees compared with one in the timolol group. Both the mean temperature and the maximum temperature correlated significantly with indices of infarct size and ischaemic area as estimated by cumulative creatine kinase release, QRS vector difference, and ST vector magnitude. The results were consistent with the view that reduction of infarct size may partly explain the reduced pyrexial response after timolol treatment. Other mechanisms are probably also involved in larger infarcts. Because high fever has detrimental haemodynamic effects in acute myocardial infarction, reduction of this response may be beneficial. The results support the early use of beta adrenoceptor blockade in acute myocardial infarction.

Body Temperature↗
PubMed1995

Clinical implications of the stress response.

A field of research that began with a curious observation in Drosophila has resulted in a new understanding of how cells respond to sudden and adverse changes in their environment. In addition through the study of the structure/function of the stress proteins, especially those which function as molecular chaperones, new insights into the details by which proteins are synthesized and acquire their final biologically active conformation have been realized. Equally exciting is the progress being made as it relates the potential diagnostic and therapeutic applications of the stress-response proteins. The use of stress proteins as the next generation of vaccines and/or their use as potentially powerful adjuvants, capable of stimulating both T and B cell responses to a particular antigen of interest appear close to becoming a reality. One wonders how many more surprises are in store for us as we continue to explore this evolutionally conserved cellular stress response.

Adaptation, Physiological↗
PubMed2006

A review of perspectives on alcohol and alcoholism in the history of American health and medicine.

This review of alcohol use and alcoholism in the history of American health and medicine reveals a range of ambiguous perspectives. In early America, alcohol was attributed with an array of medicinal uses, while habitual drunkenness was not accepted and was identified as a sin. The reformers of the temperance movement expanded upon what they regarded as the social problems associated with alcohol. In nineteenth century America, medical sectarians developed conflicting and contradictory views on health and healing, including the place of alcohol and how to address alcoholism. As the American hospital system evolved, approaches for the care and treatment that alcoholics received in hospitals had to develop as well. Progressive reforms in the early twentieth century impacted many areas of public health in the United States, but continued to embody moralism. These historical trends profoundly influenced the social and institutional responses to alcoholism that continue today, including the evolution of the modern addiction treatment system and the formulation and promulgation of the disease concept.

Alcoholism↗
PubMed2005

Genetic analysis of HIV by in situ PCR-directed laser capture microscopy of infected cells.

Behind the exponential expansion of the acquired immunodeficiency syndrome (AIDS) epidemic, there is a continuous and progressive molecular evolution of human immunodeficiency virus (HIV)-1. In this regard, the molecular analysis of viral strains infecting several anatomic compartments in humans has become critical to understanding AIDS-related pathologies and to improving emerging therapeutic protocols. Laser capture microdissection provides outstanding results in the genetic analysis of HIV-1 variants detectable in AIDS patients. The ability of the instrument to microdissect infected cells from a heterogeneous tissue compartment allows the investigator to obtain critical information regarding the genetic nature of a specific viral strain. To perform laser capture microdissection with better accuracy, a priori detection techniques may provide useful information about HIV distribution in the tissue specimen. An in situ polymerase chain reaction (PCR) assay on a serial slide results in a detailed map of the viral infection specific for the case under analysis. The knowledge of HIV distribution in the tissue section is critical for improving the dissection of infected cells by laser capture microscopy. This chapter describes laser capture microdissection and in situ PCR and its role in the analysis of the genetic nature of HIV-1 variants and quasispecies.

AIDS-Associated Nephropathy↗
PubMed2003

The human mind: building bridges between neuroscience and psychiatry.

This essay proposes the existence of four unique behavioral characteristics that distinguish Homo sapiens from its nearest evolutionary kin, the great apes. These are inventiveness, capacity for language, curiosity, and self-reflection or self-analysis. Some would counterargue that none of these features are "unique" to humans. Examples would be given of animal "intelligence" involving at times surprising problem-solving abilities. Even "conversations" between humans and parrots might be cited. However, this is to misunderstand what the focus is in the article. This is not a thesis on the continuity or discontinuities of evolution. Every well-trained biologist learns about evolution and understands that the most complex human traits have some hint of related traits in nearest relatives. Rather, the emphasis of this article has been to select and emphasize certain distinctive aspects of human behavior that are the most important features distinguishing human "uniqueness." Uniqueness may be quantified by the number and complexity of processes within the four attributes presented in this article. While this may be an interesting mathematical exercise, the author would rather take it for granted that the outcome would be that humans are significantly more complex in each of the four features referred to than the great apes. For those in the mental health field, one would hope that this overview of the most highly evolved systems in human brain may provide a useful framework where creative therapeutic processes can be applied to the ultimate beneficiary, the client or patient. This article proposes that psychosis can be considered the impossibility of conflict resolution among the special neuronal assemblies that separately mediate feelings of attachment versus abandonment, security versus anxiety, calmness versus anger, fulfillment versus helplessness, and satisfaction of sexual needs. Given this model, the role of the therapist is to consider whether the client is in touch with the various equilibrium points in their current life situation or crisis. A questionnaire designed to help access information on these internal states may work better than an oral interview because it forces the client to reflect. How much conflict does the client feel in sorting out personal priorities? Does the client have any practice at resolving internal conflicts? If unpracticed, is the client likely to act out in destructive ways to self or others to resolve the pressure of internal conflicts? I am sure that we can all think of current well-publicized destructive acts in which one has to wonder precisely what model of mind the psychotherapists were using to assist the client. At a higher level, each human has the potential to be creative. Whether expressed as curiosity about the universe and nature or inventiveness, as in improving the quality of one's life or by the use of gifted language as in art and music, the therapist needs to determine how to assist the client into these kinds of self-defined fulfillments, which one hopes will reduce the other tensions of conflict resolution. There is no doubt that the journey for both the client and therapist will be challenging. Ultimately, the journey is the reward for both the client and therapist. In closing, the following quotation seems appropriate. Sydney Brenner (2002), a pioneer in molecular biology, reviewed a current book on the Science, Politics, and Ethics of the Human Genome Project (Sulston and Ferry 2002). He states, "What I found interesting in the account is that Sulston doesn't tell us anything about the genomes he has sequenced. What did he find there that excited him? What did he learn about genes, about life, about evolution, about worlds to come? It is the play of Hamlet without Hamlet" (p. 794).

Animals↗
PubMed1999

A gasometric method to determine erythrocyte catalase activity.

We describe a new gasometric method to determine erythrocyte catalase activity by the measurement of the volume of oxygen produced as a result of hydrogen peroxide decomposition in a system where enzyme and substrate are separated in a special reaction test tube connected to a manometer and the reagents are mixed with a motor-driven stirrer. The position of the reagents in the test tube permits the continuous measurement of oxygen evolution from the time of mixing, without the need to stop the reaction by the addition of acid after each incubation time. The enzyme activity is reported as K Hb, i.e., mg hydrogen peroxide decomposed per second per gram of hemoglobin (s-1 g Hb-1). The value obtained for catalase activity in 28 samples of hemolyzed human blood was 94.4 +/- 6.17 mg H2O2 s-1 g Hb-1. The results obtained were precise and consistent, indicating that this rapid, simple and inexpensive method could be useful for research and routine work.

Adolescent↗
PubMed2005

The CellCard System: a novel approach to assessing compound selectivity for lead prioritization of G protein-coupled receptors.

Advances in high throughput screening technologies have led to the identification of many small molecules, "hits", with activities toward the target of interest. And, as the screening technologies become faster and more robust, the rate at which the molecules are identified continues to increase. This evolution of high throughput screening technologies has generated a significant strain on the laboratories involved with the downstream profiling of these hits using cell-based assays. The CellCard System, by enabling multiple targets and/or cell lines to be assayed simultaneously within a single well, provides a platform on which selectivity screening can be quickly and robustly performed. Here we describe two case studies using the beta-lactamase and beta-galactosidase reporter gene systems to characterize G protein-coupled receptor agonist activity. Using these examples we demonstrate how the implementation of this technology enables assay miniaturization without micro-fluidic devices as well as how the inclusion of intra-well controls can provide a means of data quality assessment within each well.

Animals↗
PubMed1997

Properties of intraepithelial neoplasia relevant to cancer chemoprevention and to the development of surrogate end points for clinical trials.

Cancer chemoprevention is defined as the prevention of cancer by the administration of diet supplements or drugs. A drug discovery effort should therefore focus on finding agents that will avert the process of intraepithelial neoplasia which precedes invasive cancer. Over 30 agents developed by the chemoprevention program at the National Cancer Institute are being tested against intraepithelial neoplasia of many organ sites in more than 80 clinical trials. Two basic mechanisms underlie the onset and development of intraepithelial neoplasia. First is the development of the two precursor lesions of chronic diffuse epithelial hyperplasia and genomic instability, the latter being produced by "mutator" mutations in genes responsible for genomic stability, by gene copy amplification or loss from DNA breakage-fusion-anaphase-bridge cycles, by unequal sister chromatid exchange, and by accumulation of double minutes. Second is the development of multicentric intraepithelial neoplastic lesions which independently progress through each of the following processes at a continuously accelerating rate: clonal evolution, hyperproliferation, production of genomic structural variants, and apoptosis. Recommended chemoprevention strategies based on these mechanisms are (i) the development of better technology for early diagnosis, (ii) the development of multiple agents that block intralesional proliferation at steps along the signal pathway of mitotic signal transduction and along the signal pathway of synthesis of daughter cell components, (iii) the development of nontoxic anti-inflammatory agents, anitoxidants, antimutagens, and proapoptotics, (iv) the avoidance of "clonal escape" through use of drug combinations, and (v) the use of computer-assisted quantitative image analysis to assay modulation of surrogate end points in chemoprevention clinical trials.

Anticarcinogenic Agents↗
PubMed1976

[Kidney function after reconstructive operations on the renal arteries in renovascular hypertension].

A total of 117 patients with renovascular hypertension operated upon by employing reconstructive surgery upon renal arteries for producing hypotensive effect and restoration of renal functions were examined. Examination was made before surgery, in the near (up to 6 months) and remote post-operative periods (after a lapse of up to 10 years time). Soon after the operation persistent normalization of the arterial pressure was recorded in 78 (67 per cent) of 117 patients, improvement supervened in 12 per cent of the cases, and a positive hypotensive effect could be achieved in 92 or 79 per cent of the patients. The immediate normalization and improvement in the evolution of arterial hypertension continue, as a rule, also late after surgery. Following reconstructive operations on the renal arteries with normalized arterial pressure or its improvement the great majority of the patients demonstrated re-establishment or a significant improvement of both the summary (filtration, concentration and even nitrogen-excretory) and individual renal functions (as shown by the results of radioisotope renography with I131 hippuranium and excretory urography. In patients with malignant course of arterial hypertension successful reconstructive surgery was followed by a tendency toward retrograde development of the arterial hypertension malignancy.

Arteries↗
PubMed2000

Endosaccular thrombosis of cerebral aneurysms: strategy, indications, and technique.

Endovascular occlusion of a cerebral aneurysm refers to the induction of thrombosis within the aneurysm by any of several methods, all of which make use of devices delivered through the bloodstream of the parent vessel. The type of endovascular treatment most commonly used today for aneurysm treatment is the detachable platinum microcoil designed by Guglielmi, known as the GDC. The GDC has been used more frequently and successfully over the last decade as a treatment alternative to microneurosurgical clip ligation. A continual and rapid technological evolution and increasing clinical experience of neurosurgeons and neuroradiologists using this technology have been important contributors to its success. Endovascular coil embolization may hold advantages over microneurosurgical clip ligation under selected clinical circumstances. It is also necessary to acknowledge and outline the disadvantages of this form of treatment in an unbiased manner.

Cerebral Angiography↗
PubMed1999

[Alveolar proteinosis: signs and prognosis using high-resolution computed tomography in 5 patients].

Pulmonary alveolar proteinosis is a rare idiopathic diffuse airspace disease characterized by intraalveolar accumulation of large quantities of lipoproteinaceous material. The clinical presentation and course are variable and the definite diagnosis is made by biopsy or broncho-alveolar lavage (BAL) that also constitutes the unique and empiric treatment. We report the extremely typical HRCT features of the disease found in a series of five patients diagnosed in our institution over a ten-year period. The HRCT signs and their evolution are discussed. A continuous spectrum of findings going from isolated ground glass opacities to lobular consolidation is found, but the most common and invariably present pattern consists of ground glass areas with superimposed smooth septal thickening; these areas have a patchy or geographic distribution--often termed the "crazy-paving" pattern--and are unlike pulmonary findings in any other disease.

Adult↗