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PAX genes play an important role in fetal development. Moreover, heterozygous mutations in several PAX genes cause human disease. Here we review the role of PAX2 in kidney development, focusing on the morphological effects of PAX2 mutations. We discuss the role of PAX2 in the context of an inhibitory field model of kidney branching morphogenesis and summarize recent progress in this area.
Renal Cell Carcinoma (RCC) is classified into six cell pathological types by the Thoenes classification (5). Deletion of DNA (loss of heterozeigosity: LOH) is seen with a high frequency in human RCC of all 6 types at chromosome 3p 14-25. The presence of at least three tumor suppressor genes at this domain has been pointed out. The VHL gene, one of the tumor suppressor genes (TSG), was identified in 1993 at chromosome 3p25-26 as the gene responsible for VHL disease. As a consequence, it was demonstrated that inactivation of the von Hippel-Lindau (VHL) gene is responsible for sporadic clear cell RCC. Activating mutations of c-Met receptor type tyrosine kinase has been demonstrated in papillary renal cell carcinoma families. Possible involvement of the FHIT tumor suppressor gene, located at the fragile site (FRA3B) of chromosome 3p14, has been detected in sporadic RCC. Recently, methylation of RASSF1A at chromosome 3p21.3 was pointed out in sporadic RCC. Thus, it has become apparent that chromosome 3p14-25 3 has possible TSGs for RCC. Furthermore, it was pointed out in April that germline mutation of fumarate hydratase, a Krebs cycle enzyme (FH), is present in multiple cutaneous and uterine leiomyomatosis families that develop papillary RCC. The functional significance in these genes for the development of RCC is still not apparent, except for the VHL gene. Thus, there is still a long way to go before we find all responsible TSGs in all pathological subtypes in sporadic RCC.
The structures and functions of many genes are homologous in Drosophila and humans. Therefore, studying pathological processes in Drosophila, in particular neurogenerative processes accompanied by progressive memory loss, helps to understand the ethiology of corresponding human disorders and to develop therapeutic strategies. It is believed that the development of neurogenerative diseases might result from alterations in the functioning of the heat shock/chaperone machinery. In view of this, we used Drosophila mutant l(1)ts403 with defective synthesis of heat shock proteins for studying learning and memory in a test of conditioned courtship suppression following a heat shock given at different developmental stages. High learning indices were registered immediately and 30 min after training both in the intact controls and in flies subjected to different developmental heat shocks. This indicated normal learning and memory acquisition in the mutant. At the same time, memory retention (3 h after training) suffered to different extent depending on the developmental stage. The remote effects of heat shock given during the formation of the mushroom bodies indicated the important role of this brain structure in the memory formation. The observed memory defects may result from alterations both in mRNA transport and in the functions of molecular chaperones in the l(1)ts403 mutant.
Within one day after the formation of the linear heart an adult type of electrocardiogram (ECG) can be monitored, reflecting the development of coordinated activation of the heart. The possibility that during evolution and ontogenesis of the heat, this development is achieved by localized growth of cardiac chambers rather than of a conduction system is discussed here.
This investigation examined children's capacity to decode verbal and nonverbal emotional stimuli. Children with externalizing behavioral symptoms were compared to two types of controls, including chronically ill and normally developing children. Children were requested to identify whether video scenes were happy, angry, sad, or neutral, across four different modalities including verbal, prosody, facial, and combined. Findings were that chronological age was a significant predictor of children's ability to decode emotions with older children having better developed abilities than their younger peers. Verbal intelligence also was found to be a significant predictor of the ability to decode facial expressions and combined scenes. Although the data did not support the original hypotheses that children with externalizing behavior disorders would be less accurate than controls in the decoding of emotions, findings did support a developmental progression of decoding accuracy. Recommendations within the limitations of the study design are provided which support a developmental framework in children's acquisition of the decoding of emotions.
Most pharmacotherapeutic treatments designed to treat insomnia target GABAergic activity globally in the brain. Development of new molecules having a more specific activity pathway should improve treatment efficacy and acceptance. Both subjective and objective criteria are needed to study drug efficacy. Data regarding drug effects on polysomnographic recordings are mandatory for the development of hypnotics. Whether the drug-induced sleep is comparable to normal sleep is tackled with the spectral analysis of the sleep EEG. Residual drug effects are assessed with a package of psychomotor and neurocognitive tests, and with the driving simulator test Clinical studies investigating drug efficacy and tolerability have to be conducted on large groups of patients carefully selected using polysomnographic recordings. Our knowledge about sleep will undoubtedly soon become available for treatment of insomnia.
In response to a need for a comprehensive online curriculum development and management system for medical education at the University of Pittsburgh the author, the Lab for Educational Technology (the Lab), students and faculty developed the Pitt Med Navigator website (Navigator). This completely web-based, distributed, personalized application is used by students and faculty to: 1) create, manage, and rapidly access online course resources; 2) author teaching cases, interactive multimedia presentations, and quizzes; and 3) manage a personal education portal. Four pilot courses and objective evaluations have revealed high student and faculty utilization and a high degree of perceived educational value.
To develop information systems (IS) in the changing environment of the health sector, a simple but throughout model, avoiding the techno-jargon of informatics, might be useful for the top management. A platform neutral, extensible, transparent conceptual model should be established. Limitations of current methods lead to a simple, but comprehensive mapping, in the form of a three-dimensional cube. The three 'orthogonal' views are (a) organization functionality, (b) organizational structures and (c) information technology. Each of the cube-sides is described according to its nature. This approach enables to define any kind of an IS component as a certain point/layer/domain of the cube and enables also the management to label all IS components independently form any supplier(s) and/or any specific platform. The model handles changes in organization structure, business functionality and the serving info-system independently form each other. Practical application extends to (a) planning complex, new ISs, (b) guiding development of multi-vendor, multi-site ISs, (c) supporting large-scale public procurement procedures and the contracting, implementation phase by establishing a platform neutral reference, (d) keeping an exhaustive inventory of an existing large-scale system, that handles non-tangible aspects of the IS.
Effects of hindlimb suspension or exposure to 2-G between postnatal day 4 and month 3 and of 3-month recovery at 1-G environment on the characteristics of rat hindlimb muscles were studied. Pronounced growth inhibition was induced by unloading, but not by 2-G loading. It is suggested that the development and/or differentiation of soleus muscle fibers are closely associated with gravitational loading. The data indicated that gravitational unloading during postnatal development inhibits the myonuclear accretion in accordance with subnormal numbers of both mitotic active and quiescent satellite cells. Even though the fiber formation and longitudinal fiber growth were not influenced, cross-sectional growth of muscle fibers was also inhibited in association with lesser myonuclear domain and DNA content per unit volume of myonucleus. Unloading-related inhibition was generally normalized following the recovery.
BACKGROUND: Informing parents of a severe developmental disability (SDD) in their child is a frequent, yet extremely challenging part of care at any child developmental center. In this study, which was the first to address this issue in Israel, we asked parents for feedback on their experiences in receiving such news at our center, in order to help us develop a set of guidelines for improving clinical practice. OBJECTIVE: To obtain parents' perspectives on the meeting at which they were first informed that their child has a SDD. How satisfied were they with these encounters? What factors are associated with higher and lower levels of satisfaction with these meetings? DESIGN: Mixed-method (quantitative/qualitative) questionnaire survey. SETTING: Regional HMO Child Developmental Center. SUBJECTS: Study participants were 33 parents, constituting 62% of all those whose children first received a diagnosis of SDD (mental retardation, autism/PDD, cerebral palsy, or genetic syndromes) at our center over the past seven years. MEASUREMENTS: Parents were contacted by the social worker involved in their child's care to obtain initial consent for participation in the study. A 34-item self-report survey questionnaire, containing both closed- and open-ended questions, was sent to them by mail, to be completed anonymously. Questions were based on a survey of the literature and focused on the setting of the meeting, its contents, staff behavior, parents' satisfaction with the meeting and background characteristics of the family and child. RESULTS: Almost two-thirds (63%) of respondents reported a high or very high level of satisfaction with the meeting at which they first heard the diagnosis of SDD. Both content analysis of open questions and statistical analysis of correlations between satisfaction and a series of potential predictors pointed to three main areas affecting parental satisfaction with the meeting: (1) Amount and type of information conveyed: Parental satisfaction with the meeting was higher when detailed information was provided regarding a number of issues (diagnosis, treatment options, educational settings, rights for benefits and assistance etc.), when parents were referred to additional sources of information, and when the clinician was seen to be knowledgeable and confident. (2) Attitudes conveyed by staff regarding the child's condition: Parental satisfaction with the meeting was higher when the child's strengths were also addressed (and not only problems); when the general tone was not pessimistic and some hope and optimism were also conveyed; and when expected and possible future developments were specified. (3) Staffs approach to the parents: Parental satisfaction was higher when staff was attentive to parents and empathic; when they clearly expressed willingness to accompany and assist the family over time; when they were respectful toward parents and related to them as equal partners; and when parents felt that they had been informed of the diagnosis without delay and that no information had been withheld from them. CONCLUSIONS: Parents are not inevitably dissatisfied with meetings at which they are informed that their child has a SDD. Our findings point to concrete steps that clinicians can take in order to increase the chances of parental satisfaction with these meetings.
At the present time, knowledge is one of the most important values in organizations, changing into intellectual capital through its members. The responsibility conceded to professional development obliges us to reflect on its function and its practices, seeking new forms and focuses which guarantee the development of competence in both individuals and organizations by means of concentrating on concrete results.
In a longitudinal study the british pediatrician J.M. Tanner evaluated the development of breasts (thelarche), of pubic hairs (pubarche) and age of menarche. In Hungary we did a similar evaluation in 680 girls in the years 1980 to 1986. Comparing these data in a cross-sectional study with similar data from Münster we named the results central-european study. The results are similar the Tanner ones exceptionally the duration of breast development, which was shorter than in the hitherto published longitudinal studies. Mean age of menarche in our study was 12.5 years compared with 13.5 years in the former ones. This is not a confirmation to acceleration of puberty, because in other countries age of menarche was stabile. Additionally, to thelarche, pubarche and menarche we collected data about axillarche.
In this work data on the morphological features of the heteromorphous growth of bacteria in the process of the natural development of their population are presented. The authors believe that the heteromorphous growth of cells is inherent in the normal cycle of the development of bacteria in the population and that this process is reversible. It has certain regularities, common for different bacteria, in the variability of morphological manifestations and can be regarded as one of the stages of the natural L-transformation of bacteria.
An accurate description of the population at risk for neonatal chronic lung disease is clearly of prime importance for comparative studies and the planning of interventions. Attempts to explain variations in chronic lung disease rates in such studies have been compromised by lack of a way of estimating the severity of the initial pulmonary disease as a risk factor. Therefore, a severity index was developed for use in very low birth weight (less than 1501 g) neonates. Special emphasis was placed on applicability of the index in the multicenter observational setting. Development followed a clinician panel approach, with the resulting index designed to capture clinical judgment of severity. The index was validated prospectively on neonates in a neonatal intensive care unit, and retrospectively using charts from nine hospitals nationwide. Correlations of the index with clinical judgment in the two samples were .95 and .93, respectively. In an additional validation the index combined with birth weight correctly predicted oxygen dependence status at 30 days in 36 of 42 neonates consecutively admitted to five neonatal intensive care units (P = .002). Birth weight and the severity index contributed about equally to the prediction, and therefore they seem to represent partly independent components of baseline propensity for prolonged oxygen dependence.
The "state of the art" in the development of human monoclonal antibodies is reported. The classical cellular fusion method according to well established procedures, the Epstein-Barr virus mediated B-lymphocyte transformation and the modern genetic engineering method to obtain chimeric antibodies is reviewed in detail. Although they were praised in the last five years as the most efficient drugs against cancer and infectious diseases, no great success was clinically and experimentally reported in the past. The many experimental obstacles hindered the efficient development of these promising drugs. In the last two years, however, new ways were proposed to get this new therapeutic principle on a more efficient way in order to use them in the therapeutic treatment of patients with certain cancer and infectious diseases.
Thirty-eight gilts were slaughtered on the 25th and 39th days of pregnancy, after they had received 400 I.U. PMSG treatment on the eleventh day of pregnancy. Treated and untreated animals in a group of 140 gilts and 195 adult sows were compared with each other for post-farrowing fertility performance. Weight development of embryos obtained from the slaughtered sows depended on the number of embryos alive. The survival rate of embryos from treated sows was about 5% higher than that recorded from untreated animals. Clearly increased litter sizes which, however, were associated with lower piglet birth weights were recorded from farrowing gilts and adult sows, following PMSG treatment. The conclusion is drawn that PMSG treatment, via luteotrophic action of luteinising hormone, is capable of stabilising pregnancy-related corpora lutei, resulting in higher litter sizes. Further studies will be necessary, and emphasis will have to be laid on the problem of weight development of newborn piglets, following litter-size boosting treatment.
A fetal thymus organ culture system has been developed to study the differentiation of murine thymus-derived immunocompetent cells (T cells) such that cell yields can be easily monitored. This system has been used to study the effects of monoclonal anti-I-A antibodies on the growth of T cells. The addition of anti-I-A antibodies, but not anti-H2K monoclonal antibodies, to fetal thymus organ cultures resulted in a decreased yield of lymphoid cells. Anti-I-A-treated cultures did not produce cells that gave an immune response in MLC assays. Anti-I-A antibodies stained a small subpopulation of nonlymphoid cells in untreated cultures by indirect immunofluorescence that were no longer detectable in cultures that had been pretreated with anti-I-A antibody. Culture of fetal thymus lobes at low temperature (20 degrees C) for 1 wk resulted in a decrease in lymphocyte production, as well as a concomitant increase in the frequency of Ia-positive nonlymphoid cells. Co-culture of fetal liver or anti-thy-1 plus complement-treated adult bone marrow with such Ia-positive cell-enriched fetal thymus lobes at 37 degrees C resulted in the production of T cells. Anti-Thy-1.1 or -1.2 staining by indirect immunofluorescence of cells obtained from co-cultures that differed at the Thy-1 locus showed that the T cells produced were derived from the bone marrow or fetal liver. T cell production occurred in both syngeneic and allogeneic cocultures. However, if co-cultures were made by using 14-day gestation fetal thymus instead of fetal liver or bone marrow as donors of T cell precursors, T cell growth was observed only in syngeneic combinations. These results suggest that Ia-positive nonlymphoid cells play a role in the development of T cells in the fetal thymus, and that "thymus processed" T cell progenitors (but not the more immature progenitors in the fetal liver or bone marrow) are self-Ia restricted in their differentiation.
During ascidian embryogenesis a tissue-specific enzyme, muscle acetylcholinesterase (AChE) may first be detected histochemically in the presumptive muscle cells of the neurula. In order to investigate the 'clock' or counting mechanism that is determining the time when AChE first appears, Whittaker's experiment (1973) has been repeated using eggs of the ascidian, Halocynthia roretzi. Embryos that had been permanently cleavage-arrested with cytochalasin B were able to differentiate AChE in their muscle lineage blastomeres. The time of first AChE occurrence in embryos that had been cleavage-arrested in the 32-cell stage with cytochalasin B was about the same as in normal embryos. This result indicates that the clock is not apparently regulated by the events of cytokinesis. The early gastrulae which had been arrested with colchicine or with colcemid could develop AChE activity, although no histochemically detectable AChE activity was observed in the cleavage-stage embryos that had been arrested with either drug. Therefore the clock does not seem to be controlled by the mitotic cycle of the nucleus. It is suggested that the cycle of DNA replication may be related to the regulation of the clock that is determining the time of development of histospecific protein.