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PubMed2006

Comparative genomics of vertebrate Fox cluster loci.

BACKGROUND: Vertebrate genomes contain numerous duplicate genes, many of which are organised into paralagous regions indicating duplication of linked groups of genes. Comparison of genomic organisation in different lineages can often allow the evolutionary history of such regions to be traced. A classic example of this is the Hox genes, where the presence of a single continuous Hox cluster in amphioxus and four vertebrate clusters has allowed the genomic evolution of this region to be established. Fox transcription factors of the C, F, L1 and Q1 classes are also organised in clusters in both amphioxus and humans. However in contrast to the Hox genes, only two clusters of paralogous Fox genes have so far been identified in the Human genome and the organisation in other vertebrates is unknown. RESULTS: To uncover the evolutionary history of the Fox clusters, we report on the comparative genomics of these loci. We demonstrate two further paralogous regions in the Human genome, and identify orthologous regions in mammalian, chicken, frog and teleost genomes, timing the duplications to before the separation of the actinopterygian and sarcopterygian lineages. An additional Fox class, FoxS, was also found to reside in this duplicated genomic region. CONCLUSION: Comparison of loci identifies the pattern of gene duplication, loss and cluster break up through multiple lineages, and suggests FoxS1 is a likely remnant of Fox cluster duplication.

Animals↗

PubMedDate not supplied

History and evolution of stomas.

This article, describes the evolution of stoma formation from earliest times to current innovative procedures. Surgeons are continually trying to develop new procedures so that they can offer less socially incapacitating alternatives to the abdominal stoma.

Enterostomy↗

PubMedDate not supplied

[Conservative treatment of ectopic pregnancies: comparison of velocity of decrease of beta-HCG between spontaneous and methotrexate induced resorptions].

The evolution of the process can take two different directions. If an Intact pregnancy continues to grow, there is a tubal abortion or a rupture of the Fallopian tube. In the oppsote case, there is spontaneous resorption of the tubal pregnancy. In certain cases with the application of methotrexate, the ectopic pregnancy growth can be interrupted and spontaneous resorption can be induced. Nowadays, the international standards of treating patients with early ectopic gravidities and no peritoneal effusions, with beta-HCG values below 6000 UI/l, gestational sac diameter below 3 cm, and without any visible heart action, imply methotrexate treatment. The objective of this study is to prove the efficiency of methotrexate use in patients who meet the above criteria. The first group did not manifest satisfying decrease of [beta-HCG after two measurements, so methotrexate was used, while the second group showed satisfying decrease of beta-HCG, measured on the third day. Comparing the velocity of decrease of beta-HCG level among both groups of patients, it was proved that iatrogenically induced decrease, that is to say the achieved resorption, was equal to the spontaneous resorption, which justified the use of methotrexate in ectopic pregnancy treatment.

Embryo Loss↗

PubMed2006

[The acute pseudobstruction of the colon, or Ogilvie's syndrome: a rare cause of acute abdomen, high mortality and associated pathologies in an internal medicine department].

The acute pseudobstruction of the colon or Ogilvie's syndrome is a infrequent pathology of acute or subacute evolution, that is associated to different clinical or surgical pathologies, and whose pathophysiology continues to be unknown. The treatment begins with general measures and if these are not effective, with the surgical decompression of colon to avoid the most serious complication, and frequently that is perforation of the cecum. We present a case of an acute and idiopathic dilatation of colon in an adult man who entered by an episode of acute respiratory insufficiency, and that was solved with preservative medical treatment.

Abdomen, Acute↗

PubMed2003

Action mechanism of a selective anti-cyanobacterial compound, argimicin A.

Argimicin A is a potent anti-cyanobacterial compound produced by one of algae-lysing bacteria, Sphingomonas sp. M-17. Since the compound seemed to exhibit selective activities against cyanobacteria and such selectivity were considered to be quite rare, the mode of action of argimicin A was investigated. Argimicin A showed a unique delayed action, i.e., the cyanobacterial cell division continued until at least 36 hours treatment even though the decrement of oxygen evolution has been observed at 24 hours treatment. The compound is concluded to be a photosynthetic inhibitor which interrupts electron transport chain prior to photosystem II. From the preliminary fluorescent spectrum of argimicin A treated cyanobacterial cells, the site of action was speculated to be photo energy transfer from a cyanobacterial specific complex of accessory protein pigments, phycobilisome, to photosystem II.

Animals↗

PubMed2000

[The national program of pediatric transplantation].

The national programme for paediatric transplants currently implemented at the Istituto Superiore di Sanità is one of the first results of the efforts devoted to the definition of an efficient co-ordination policy of the transplantation activity in Italy. Since 1997 the programme has allowed all transplant centres throughout Italy to share unified waiting lists for kidney, heart, lung and liver, which gives paediatric patients a much better possibility than with local waiting lists. We present the regulations, criteria and operative solutions adopted to make the programme work, and the analysis of the data collected in these three years. The analysis gives statistical information on the composition and evolution of waiting lists and transplants done, which may be useful in the continuous process of revision and improvement of the criteria for recipient selection.

Adult↗

PubMed2000

Problems and solutions for artificial kidney.

The uremic syndrome is the prototype of a slowly progressive endogenous intoxication, when a detoxifying organ (in this case the kidney) fails. It is characterized by the gradual retention of a host of metabolites, which is in part corrected by dialysis, allowing survival with an acceptable quality of life. This paper reviews the main problems of hemodialysis today, and possible solutions. Adequacy of dialysis is estimated currently from the concentration of urea, which is used as a marker molecule. The problem is that urea is not really toxic by itself. Other markers with known toxicity, such as middle molecules (300-12,000 D) and protein bound compounds should be considered. The question then arises whether the classical dialytic concept based on diffusion should be modified. Adsorptive systems may be strong binders of protein bound solutes. Other concepts that are now arising, and that may add to toxin removal, are slow and daily dialysis. Another question that could be raised is whether it would not be possible to support toxin removal, by administering peroral sorbants. Dialysis patients are prone to vascular disease and die early from cardio-vascular complications. One of the solutions for this problem could be to bring the blood of dialyzed patients into contact with antioxidants (e.g. vitamin C or E). The risk for perdialytic hemodynamic instability is increased in many dialysis patients. The ideal solution would be to develop an "intelligent" dialysis system, whereby blood volume and plasma osmolality are sensed continuously, and ultrafiltration and dialysate sodium concentration are adapted in function of this evolution. An adequate vascular access is indispensable to perform adequate dialysis, but thrombotic/stenotic complications are frequent. This could be prevented by molecular biological modification of vascular grafts, whereby genetic information is entered into the cells, blocking the natural chain of events that otherwise unavoidably leads to neointimal hyperplasia and atherosclerosis. Another old dream is to develop a wearable artificial kidney, whereby patients can move around, and be treated 24 hours per 24 hours, in stead of being treated intermittently at a specific location by the dialysis machine. According to some authors, part of the natural renal function could be replaced by cultured renal tubular cells, which are brought in contact with the blood of the patients. It is concluded that thrilling improvements lie ahead in the future, but the following questions arise: 1) What is the cost of all these improvements? 2) Will it remain possible to reimburse all this? 3) What is going to happen in transplantation, mainly regarding improvements in immunosuppression and the development of xenotransplantation?

Forecasting↗

PubMed1992

[Meta-analysis of the prognosis of thoracic aortic dissection: changing mortality in the last four decades].

The acute dissection of the thoracic aorta is a potentially lethal event with a death rate of 1 to 2% per hour urging for undelayed diagnosis and adequate treatment. First, this paper highlights both the demographic characteristics and the classification according to anatomical and prognostic criteria, i.e. class I to III according to DeBakey and type A and B according to Daily (or Stanford). Moreover, the etiology of aortic dissection is explained, including factors such as degenerative changes of the aortic media layer, chronic trauma from hypertension, primary connective tissue disease and acute deceleration trauma. Second, the clinical criteria of acute (within 14 days of the index event) and chronic dissection (> 14 days) is discussed with respect to the current literature. The dominant part of this paper represents a meta-analytic approach comprising all available literature sources with respect to emerging changes in the prognosis of thoracic aortic dissection over 40 years as a function of either the type, the anatomic location, the acuity or the impact of medical or surgical treatment of this disorder. The meta-analysis revealed that in acute and chronic type A dissection medical treatment alone failed to lead to a significant improvement of 30 day-mortality rate (Tables 1 and 2, Figure 1). However, with surgical interventions the 30 day-mortality rate was continuously lowered from 60% to 10% within the past 30 years. A similar evolution was observed for the chronic type A dissection (Tables 3 and 4, Figure 2). Furthermore, the meta-analysis revealed that the acute type B dissection benefits from medical treatment, especially antihypertensive medication since the 30 day-mortality of 40% in 1960 decreased to less than 10% at present with monitoring and effective medication (Tables 1 and 2, Figure 3). In case of chronic type B dissection the literature survey revealed mortality numbers fluctuating between 2% and 20% without a clearcut beneficial effect of medical therapy throughout these years, though possibly revealing some advantage over surgical treatment. Thus, both for the acute and chronic type B dissection the antihypertensive therapy is considered treatment of first choice, whereas surgical interventions may be necessary for complicated and progressive cases. In summary, compared to the natural course of thoracic aortic dissection with only 10% survival-rate after one year of onset (Table 9, Figure 5), any effective mode of treatment may significantly lower the high spontaneous death rate.(ABSTRACT TRUNCATED AT 400 WORDS)

Aortic Dissection↗

PubMed2004

Advances in diabetes for the millennium: healthcare systems and diabetes mellitus.

Diabetes presents a host of management issues to the practitioner. With the increasing role of managed care systems, the care of diabetic patients has created many issues in the relationship of physicians and third-party reimbursement agencies. We predict a progressive evolution of diabetes care in light of these changes. The diabetic population will continue to grow rapidly. Collaborative care systems will expand. The paper medical record will be replaced by electronic documentation. The technology of diabetes care will progress rapidly in providing office and home care for diabetes patients. The increasing cost of these interventions and the growing diabetic population will challenge the reimbursement system. We will have to seek for more cost-effective approaches in light of these factors.

Delivery of Health Care↗

PubMed2006

The Medical Library Association's professional development program: a look back at the way ahead.

OBJECTIVE: Reflecting patterns evident in past Janet Doe Lectures, the 2005 address reviews the Medical Library Association's (MLA's) professional development activities from their beginnings after World War II. A group of related but separate activities is traced through the establishment of an integrated professional development program. A further objective is to introduce newer members of MLA to their heritage and to remind others how the association has reached this point in its history. SETTING: The lecture provides an overview of the evolution of MLA's professional development program-with emphasis on certification and continuing education in the early years. It further reflects briefly on some of the more recent MLA activities that have greatly impacted professional development and underscores some new initiatives. ANALYSIS: The efforts of a virtual who's who of MLA's membership have been responsible for the convergence of the association's efforts over more than half a century to provide a comprehensive professional development program. As a participant in MLA's professional development activities for more than forty years, the 2005 lecturer provides a personal view of the growth and expansion of the program. CONCLUSIONS: Professional development has been a hallmark of MLA for many years. The association's challenge is to continue to develop creative and innovative programs, to continuously review and revise existing programs, and to have the vision and vitality to maintain a viable program that will provide the membership with the knowledge and skills needed to function effectively now and in the future.

Certification↗

PubMedDate not supplied

[Evaluation of the pharmacovigilance follow-up of zidovudine].

A therapeutic committee was established in Toulouse Regional University Hospital in order to prescribe zidovudine in patients suffering from AIDS. Using an informatic card, the side effects were evaluated in the 125 patients treated by Zidovudine since the creation of the Committee (from July 1987 to January 1989). Zidovudine was prescribed from May 1987 to June 1988 at the total dose of 1,200 mg daily from June 1988 at 900 mg daily. The most frequent side effects were hematologic: zidovudine used alone (or associated with non hematotoxic drugs) elicited in 21.2% of patients a neutropenia (defined as a number of neutrophils less than 1,000/mm3), in 2.4% anaemia (haemoglobin less than or equal to 9 g/100 ml) and in 4.8% neutropenia associated with anaemia. When zidovudine was administered with hematotoxic drugs, neutropenia, anaemia or the association of both were observed in 12.0%, 3.2% and 2.4% of patients respectively. These hematologic side effects were always regressive after drug cessation. However, it is important to underline the low incidence of hematological side effects on red cells of zidovudine in the present study. This result is unexpected. The other side effects of Zidovudine (used alone) did not led to modification in drug treatment: gastrointestinal disturbances (30.4%), headaches (16.8%), insomnia (13.6%), somnolence (6.4%).... These side effects appeared during the four first months and decreased with the continuation of drug treatment. Their imputation was difficult to define and differentiate to evolution of the disease.

Computers↗

PubMed1985

[Biologic individuality between genetics and environment. On the formation of the biologic ego].

Histocompatibility antigens represent the biological basis of individuality. They make men different from one another and represent the essence of "self" which is continuously protected from "non self" by the immune system. Both fecundation and the evolution of pregnancy are favoured by a marked difference in histocompatibility antigens of the mother and father as well as of the mother and the fetus. The biology of pregnancy also find expression in the neonate: different percentages of the subclasses of T lymphocytes and low levels of NK cells and function. On the whole these data and the correlation between histocompatibility antigens and diseases allow life to be interpreted as an immune phenomenon and human individuality as an essentially immunological "biological Ego". Analogies may be found between the "biological" and the "psychological Ego". Many alterations may affect the protective immune network giving rise to primary or acquired immunodeficiencies. They may be expressed slowly and progressively or suddenly. The immune alterations of Down's syndrome and those of infantile AIDS may be taken as heuristic examples in this sense.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

Hepatic fibrosis in alcoholic steatosis. Morphologic aspects and evolutive tendencies.

Alcoholic hepatic steatosis, considered for a long time as a reversible "harmless" disease, is now re-evaluated according to the concept of cirrhosis without cell necrosis and inflammation. The study of 166 biopsies from alcoholic hepatic steatosis has demonstrated the presence of fibrotic process in 25 (15%) of the cases. Histologic and electron microscopic examination have supplied data on the distribution of this fibrosis (perivenous, perisinusoidal and extensive) as well as on the cells involved in collagen synthesis; myofibroblasts, fat storing cells (Ito cells) and the hepatocyte itself. Peritoneoscopy revealed aspects of incipient portal hypertension in some of the cases. Follow-up in time with reiteration of morphologic exploration at intervals of 2 to 3 years has shown the possible evolution toward cirrhosis in cases of steatosis with fibrosis when ethanol consumption is continued. Detection of early fibrosis, in patients with alcoholic steatosis, by means of morphologic or biochemical methods would be necessary for its therapeutic implication: possible reversibility by abstinence from alcohol and antifibrogenic therapy.

Biopsy↗

PubMedDate not supplied

Drug induced hepatitis.

During the last decade an increased incidence of the adverse reactions to drugs with liver involvement was found. The liver lesions produced by drugs constituted a constant concern. We followed the course of liver disease produced by tuberculostatics, cytostatics, antidepressive, antibiotics, narcotics, antirheumatics, by biochemical, immunological and morphological investigations (needle biopsy of the liver with optical and electronic microscopy). The pattern of the damage to the liver ranges from minimal functional changes to severe aspects with cytolysis and cholestasis. Hypersensitivity to drugs (cutaneous eruption, rash, fever, eosinophilia) were observed only in three cases. The cholestatic clinical form was the most frequently encountered, raising problems of differential diagnosis with acute viral hepatitis and obstructive jaundice. Clinical evolution of drug induced hepatic lesions is favourable as soon as the administration of drug is arrested. Chronic evolution, as reported in the literature when the administration of hepatotoxic drug is continued, was noted only in one patient who was using Chlorpromazine.

Biopsy, Needle↗

PubMedDate not supplied

[Physiologic mechanisms of spatial hearing].

The ability to localize the sources of clicks and tone-bursts of various frequency, duration and insensity coinciding with location of feeding troughs, was studied in 15 cats with motor alimentary conditioning technique during unilateral cold elimination or after unilateral ablation of the central (fields AI, AII, Ep, IT) and peripheral parts of the auditory system. Such animals projected the sound only to the side opposite to the intact hemisphere, on the continuation of the interaural axis. It is suggested that in the course of evolution, animals developed several mechanisms of localization, each of which preserves its function and is involved as a sub-system in the binaural bihemispheric mechanism.

Animals↗

PubMed1993

[Clinical and analytical manifestations of primary antiphospholipid antibody syndrome].

STUDY OBJECTIVE: Description of the clinical and analytical manifestations of 8 patients with Primary Antiphospholipid Syndrome (PAPS). DESIGN: Series of cases. SETTING: Patients seen in the Internal Medicine Department of a third level Medical Center in Malaga Province. PATIENTS AND INTERVENTIONS: We describe the symptoms and signs, as well as the analytical determinations that may be related with autoimmunity in 8 patients diagnosed of PAPS (Harris' Criteria). The antiphospholipid antibodies were determined by a) Biologic false-positive Venereal Disease Research Laboratory (BFP-VDRL), b) Lupus Anticoagulant (LAC): Enlargement of the activated thromboplastin partial time > 6" and Exner test, c) Anticardiolipin antibodies (aCL), IgG (UGPL/ml), IgM (UMPL/ml) by enzyme-linked immunosorbent assay (ELISA). RESULTS: Four patients were females and four males. The mean age was 35.1 +/- 13.6. None of the patients had criteria of systemic lupus erythematous. The principal clinical manifestations of the PAPS were the venous and arterial thrombotic events in different areas (7 patients); The female patient that didn't have thrombotic event presented thrombocytopenia. Only one patient had 1 abortion. The four females had livedo reticularis (LVR), associated in two of them with arterial hypertension and stroke (Sneddon syndrome). Others manifestations seen, have been, Raynaud's phenomenon, acrocyanosis, migraine, arthritis and myositis. All the patients had IgG aCL, 3 IgM aCL, 7 enlargement of the activated thromboplastin partial time and none presented VRL. Five patient had positive antinuclear antibodies (ANA), but none of them had anti- DNA, hypocomplementemia nor lymphopenia. As far as treatment goes three of the patients are anticoagulated with continuous dicoumarins . The remaining patients keep treatment with platelet antiaggregant, had a satisfactory evolution. CONCLUSIONS: This group of patients presented venous and arterial thrombotic events such as principal manifestation of the PAPS. The most sensitive test to detect antiphospholipid antibodies were the enlargement of the activated thromboplastin partial time and the aCL. It could be interest the determination of aCL in young people the present thrombotic events without another apparent cause.

Abortion, Spontaneous↗

PubMed1993

Renal replacement therapy for the critically ill--precarious progress. Part II. Technical aspects and clinical application.

Renal replacement therapy has evolved significantly in the last 15 years. Evolution has produced diversity in both techniques and terminology. Theoretical advantages of the continuous over intermittent techniques in critically ill patients exist. Limited clinical evidence supports this, but a clear reduction in mortality or morbidity has yet to be shown. In Part I of this review the terms and techniques used were defined and the physiological aspects of renal replacement therapy discussed. In this part the technical aspects and associated problems are discussed and a prescription for an effective application of the technique in critically ill patients is provided.

Humans↗

PubMed1999

Human evolution: origins of modern humans still look recent.

That modern humans have a relatively ancient origin has been suggested on the basis of fossil and genetic evidence. But DNA sequences from an extinct neanderthal, and phylogenetic analyses of hundreds of human and ape sequences, continue to support a recent origin for modern humans.

Africa↗