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2.
Eur J Hum Genet ; 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38355960

ABSTRACT

Genetic counselling education and training in Europe spans a continuum of 30 years. More master programs are opening due the demand for qualified genetic counselors. This report describes the evolution of training in Europe and the current state of genetic counselling training programs. Directors of master programs in Europe were invited to complete an online survey describing their program, including year of commencement, course duration, number of students and frequency of intake and number graduating. Results of the survey were presented at a closed meeting at the European Society of Human Genetics conference in 2022 along with a facilitated stakeholder engagement session in which 19 professionals participated to understand the challenges in delivering genetic counselling education in Europe. A total of 10 active programs exists in Europe with the first training program starting in 1992. The majority of training programs have a 2-year duration, with just over half of programs having an annual intake of students. Up to May 2022, 710 students have graduated from genetic counseling training programs across Europe. Of these, 670 students graduated from European Board of Medical Genetics-registered programs. Arranging clinical placements, clinical and counseling supervision of students, research collaboration for MSc research projects and incorporating genomics into the curriculum were identified as current challenges for genetic counseling education. Genetic counseling is still a developing profession in Europe and this historical and current view of the European genetic counselor pathways, allows for educational and professional standards to be examined as the profession evolves into the future.

3.
J Community Genet ; 14(1): 101-113, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36414927

ABSTRACT

In recent decades, genetics has undergone important technological advances. The rapid shift to genomics has made a strong impact on health systems around the world. In Portugal, this huge increase in consultations and typologies of genetic tests has joined the serious limitations of the few existing genetics services. The following study aims to characterize the current state of the network of genetics services in Portugal regarding its functioning, main challenges, and opportunities. Five semi-structured interviews were conducted, corresponding to 83.33% of the directors of the public genetics services of the National Health Service. Four thematic categories emerged from the analysis: (1) specialty and technical developments, (2) structural difficulties, (3) potentialities, and (4) future directions. The developments are due to the emergence of more comprehensive genetic applications, specific protocols and patient referral standards, and accreditation of services. The main difficulties encountered in the functioning of the services were difficulty in obtaining funding, lack of human resources, service overload, and lack of exclusive time for training and research. The potentialities mentioned were the establishment of multidisciplinary teams and the best articulation with specialists from other areas. Among the various future directions pointed out, better management of patients' waiting lists, the importance of research, the simplification of test request procedures, and the creation of specialized units inside the genetic services, were reported. The results showed several gaps in the practice of medical genetics that should be addressed with the development of public policies for the recognition and restructuring of medical genetics in health care.

4.
Chem Commun (Camb) ; 54(31): 3843-3846, 2018 Apr 12.
Article in English | MEDLINE | ID: mdl-29594309

ABSTRACT

An iridium complex featuring a metalated lutidine-derived CNP ligand reacts with KOtBu to yield a dimeric species with the two metal centers bound to the opposite ligands through the CHN arms. Furthermore, reaction with H2 in the presence of KOtBu of the same iridium derivative results in the hydrogenation of the -CH[double bond, length as m-dash]CH- imidazolylidene moiety of the complex. NMR spectroscopy monitoring of the latter reaction supports the initial formation of a dihydride iridium complex containing an imidazolylidene ligand fragment that is hydrogenated after prolonged reaction time.

5.
Clin Genet ; 93(4): 891-898, 2018 04.
Article in English | MEDLINE | ID: mdl-29251775

ABSTRACT

The main objective of our study was to explore whether, and to what extent, genetic counselors' characteristics impact on their tasks in practice. Specifically, we explored the complementariness between genetic counselors and medical geneticists and therefore looked at the most relevant tasks of genetic counselors, according to genetic counselors themselves and according to the medical geneticists they work with. A total of 104 genetic counselors and 29 medical geneticists from 15 countries completed a purposefully designed questionnaire. Results showed that most genetic counselors in Europe perform similar tasks, irrespective of their backgrounds. When looking at the factors influencing genetic counselors' roles data showed that the type of tasks performed by genetic counselors is associated with the years of experience in the field, not with their background or education. Of particular interest was the consensus between genetic counselors and medical geneticists regarding the genetic counselor's role. Not surprisingly, tasks with more psychosocial implications were seen as genetic counselors' eligibility while tasks with more medical implications were seen as medical geneticists' attribution. Our study shows that most genetic counselors work in tune with international recommendations and seem to be supportive of multidisciplinary teams. Corroborating our data with previous research, we discuss potential implications for practice and training in genetic counseling.


Subject(s)
Counselors/standards , Genetic Counseling/standards , Genetics, Medical/education , Preceptorship/standards , Europe , Genetics, Medical/standards , Humans
6.
J Community Genet ; 7(2): 107-18, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26452349

ABSTRACT

The need for appropriately trained genetic counsellors to support genetic healthcare is now acknowledged. However, while programmes for education of genetic counsellors exist in a number of countries, these do not conform to any specific international standards. As genetic techniques, educational standards and professional standards have been evolved, and with increasing mobility of genetic counsellors, it is of great importance to have some comparison of education and training between different countries. This systematic review was conducted to determine the components of educational programmes for genetic counsellors worldwide that have been published in peer-reviewed literature. Databases were searched for studies published in English from 2000 to 2014 related to the topic. We identified 406 potential papers, of these, 11 studies met the inclusion criteria. The findings indicate that, in most cases, the theoretical components of genetic counsellor programmes conform to the recommendations and requirements of relevant professional bodies. However, clinical preparation of genetic counsellors in real-life professional practice settings seems to be less well addressed as this is essential to ensure genetic counsellors are able to provide safe patient care after graduation. Further work to gain agreement internationally on genetic counsellor education is needed.

7.
Dalton Trans ; 44(15): 6987-98, 2015 Apr 21.
Article in English | MEDLINE | ID: mdl-25780987

ABSTRACT

The reactivity of different heteroscorpionate ligands based on bis(pyrazol-1-yl)methane, with different iridium-(i) and -(iii) precursors is reported. The reaction of the heteroscorpionate lithium salts "Li(bdmpza)", [bdmpza = bis(3,5-dimethylpyrazol-1-yl)acetate], "Li(bdmpzdta)" [bdmpzdta = bis(3,5-dimethylpyrazol-1-yl)dithioacetate] and "Li(S)-mbpam" [(S)-mbpam = (S)-(-)-N-α-methylbenzyl-2,2-bis(3,5-dimethylpyrazol-1-yl)acetamidate] with 1 equivalent of [IrCl3(THF)3] in THF for 18 h affords high yields of neutral and anionic heteroscorpionate chloride iridium complexes [IrCl2(bdmpza)(THF)] (), [Li(THF)4][IrCl3(bdmpzdta)] () and [IrCl2{(S)-mbpam})(THF)] (). Solution of complex in acetonitrile at room temperature leads to complex [IrCl2{(S)-mbpam})(NCCH3)] (). Complexes and were isolated as enantiopure compounds. The reaction of the lithium salt "Li(bdmpza)" with [IrCl(η(4)-CH2[double bond, length as m-dash]C(Me)C(Me)[double bond, length as m-dash]CH2)]2 in THF for 18 h gave the Ir(i) complex [Ir(bdmpza)(η(4)-CH2[double bond, length as m-dash]C(Me)C(Me)[double bond, length as m-dash]CH2)] (). The reaction of complex with CO (2 atm) at room temperature leads to a new complex of Ir(iii), [Ir(bdmpza)(k(2)-CH2C(Me)[double bond, length as m-dash]C(Me)CH2)(CO)] (). Treatment of heteroscorpionate ligand precursors "Li(bdmpza)" and "Li(bdmpzdta)" with [IrCp*Cl2]2 in THF yielded the iridium(iii) complexes [Ir2Cp*2Cl2(bdmpzx)] (x = a , x = dta ). These complexes have helical chirality due to the demands of the fixed pyrazole rings. The stereoisomerism and the self-assembly processes of these helicates have been studied in some detail in solution by NMR spectroscopy and in the solid state by X-ray diffraction. Mixtures of M- and P-handed enantiomers were obtained. Complex undergoes a decarboxylation process initiated by the HCl generated in the previous step leading to the known ionic complex [IrClCp*(bdmpm)][IrCl3Cp*] [bdmpm = bis(3,5-dimethylpyrazol-1-yl)methane] (). The structures of the complexes were determined by spectroscopic methods and the X-ray crystal structures of , , and were also established.

8.
J Genet Couns ; 24(4): 616-25, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25363284

ABSTRACT

Quality assessment of genetic counseling practice for improving healthcare is a challenge for genetic services worldwide; however, there is scarce literature regarding quality issues in genetic counseling in the context of presymptomatic testing for late-onset neurological diseases (Paneque et al. 2012) The aims of this qualitative study were to: (1) explore the views of professionals' who provide genetic counseling services for presymptomatic testing for late-onset neurological diseases regarding relevant quality indicators for counseling practice; and (2) examine current assessment of such counseling practice for Portuguese genetic services. Quality indicators are a means of measuring either the process or outcomes of patient services, with the aim of evaluating and improving quality of care (Mainz 2003). In this study, we defined quality indicators as measurable outcomes of the counseling process that may reflect good professional practice and desirable end-term effects. We undertook interviews with 18 genetic health professionals (85 % of all genetic counseling professionals involved) from the major genetic services in Portugal. Results indicate that professionals valued some core components of genetic counseling, including providing information and decision-making support, informing the consultand about the genetic counseling protocol, as well as exploring motivations, expectations for test results, consequent anticipated life changes, psychosocial adjustment, and personal and familial experience with the disease. Professionals were not, however, able to clearly elucidate quality indicators for effective practice and some reported they had not reflected on that topic before. Professionals also reported specific challenges in their practice, such as ambiguity of the health/illness status and affirming consultands' autonomy. Results of the study have revealed a lack of knowledge about quality indicators and tools to assess counseling practice. A credible set of quality indicators for presymptomatic testing is required as a foundation for the development of specific tools.


Subject(s)
Genetic Counseling/psychology , Genetic Counseling/standards , Genetic Testing/standards , Neurodegenerative Diseases/genetics , Quality Indicators, Health Care/standards , Quality of Health Care/standards , Adult , Asymptomatic Diseases , Cooperative Behavior , Female , Humans , Interdisciplinary Communication , Male , Neurodegenerative Diseases/diagnosis , Neurodegenerative Diseases/psychology , Portugal
9.
J Community Genet ; 4(4): 451-60, 2013. tab, ilus
Article in English | CUMED | ID: cum-76727

ABSTRACT

Cuba reports the highest worldwide prevalence of spinocerebellar ataxia type 2 (SCA2) and the greatest number of descendants at risk. A protocol for genetic counseling, presymptomatic testing, and prenatal diagnosis of hereditary ataxias has been under development since 2001. Considering that the revision of the experience with prenatal diagnosis for SCA2 in Cuba would enable comparison of ours with international findings, we designed a descriptive study, based on the retrospective revision of the medical records belonging to the 58 couples that requested their inclusion in the program, during an 11-year period (2001-2011). Most of the participants in the prenatal diagnosis program were known presymptomatic carriers, diagnosed through the presymptomatic testing in the same period of study, for an uptake among them of 22.87 percent (51 out of 223). In 28 cases, the fetuses were carriers, 20 of these couples (71.43 percent) decided to terminate the pregnancy; the rest continued the pregnancy to term, this resulting in a predictive test for their unborn children. A predominance of females as the at-risk progenitor was observed. Except for a slightly lower average age, the results attained in the Cuban SCA2 prenatal diagnosis program resulted similar to the ones reported for Huntington disease in other countries. It is necessary to have easy access to the Cuban program through its expansion to other genetic centers along the island. Future research is needed to evaluate the long-term impact of both the predictive testing in unborn children and the selection of other reproductive options by the at-risk couples (AU)


Subject(s)
Humans , Male , Female , Prenatal Diagnosis/methods , Spinocerebellar Ataxias/congenital , Spinocerebellar Ataxias/diagnosis , Spinocerebellar Ataxias/genetics , Prenatal Care , Risk
10.
Clin Genet ; 83(6): 518-24, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23495852

ABSTRACT

Having reported the world's highest prevalence of spinocerebellar ataxia type 2 (SCA2), health professionals in Cuba developed a program for the predictive testing of this condition. Between February 2001 and December 2011, a total of 1050 individuals requested their inclusion in the presymptomatic testing (PST) program. Their medical records were retrospectively analyzed in the present descriptive study. A total of 768 participants completed the protocol, 204 withdrew and 78 were excluded. The PST uptake was 24.91%. Females predominated and 70.96% had negative test results. Their main motivations were risk assessment in their descendants, physical and psychological preparation to cope with the disease and planning for the future. The profile of Cuban participants in the predictive testing program is similar to the one reported for other programs all over the world, nevertheless the genetic counseling practice at the community level is a distinctive aspect, which is valuable in providing at-risk individuals with wide and proper knowledge before their testing inclusion request. The SCA2 predictive testing program has high uptake rates and is renowned in our population. Future research is needed to assess the long-term psychological impact in the participants, their partners and relatives.


Subject(s)
Genetic Predisposition to Disease/genetics , Genetic Testing/methods , Spinocerebellar Ataxias/diagnosis , Spinocerebellar Ataxias/genetics , Adaptation, Psychological , Adolescent , Adult , Aged , Aged, 80 and over , Cuba/epidemiology , Family Health , Female , Genetic Counseling/psychology , Genetic Counseling/statistics & numerical data , Genetic Predisposition to Disease/psychology , Genetic Testing/statistics & numerical data , Humans , Male , Middle Aged , Prevalence , Retrospective Studies , Risk Assessment , Spinocerebellar Ataxias/epidemiology , Truth Disclosure , Young Adult
11.
Enferm. glob ; 11(28): 453-464, oct. 2012.
Article in Spanish | IBECS | ID: ibc-105595

ABSTRACT

Objetivo: Evaluar el nivel de conocimientos de la sexualidad en la gestación previos y posteriores a un programa formativo implementado por un grupo de gestantes en el segundo y tercer trimestre. Material y método: diseño cuasi-experimental pre-post test de un único grupo. Participaron 40 mujeres grávidas de bajo riesgo que se encontraban en su segundo y tercer trimestre de gestación. Todas eran de raza blanca. El 85% de las gestantes comprendían una edad entre 20 y 35 años, un 60% eran primigestas. Resultados: al 60% de las mujeres del estudio les ha afectado el embarazo a su vida sexual. El trimestre que ellas creen que pueden disfrutar más del sexo, en un primer cuestionario el 62.5% contestaron que en el segundo, después de implantar el programa, el 95% dieron esa respuesta. Entre las diferentes técnicas sexuales que existen, el 87.5% la conocían en un principio, después de realizar nuestro programa el porcentaje aumentó a un 97.4%. En cuanto a los beneficios de los ejercicios de Kegel, en un primer cuestionario tan sólo el 25% sabían la respuesta correcta, mientras que más tarde aumentó a un 85% y su práctica era realizada un 12.5% antes de la intervención, y después un 40%. Discusión-Conclusión: después de aplicar nuestro programa específico se notaron algunas mejoras en el nivel de conocimientos y actitudes sexuales aunque debido probablemente a la pequeña muestra utilizada no se han encontrado resultados estadísticamente significativos salvo en una variable (práctica de Kegel) (AU)


Objective: Evaluate the level of knowledge of sexuality in pregnancy before and after a training program implemented by a group of pregnant women in the second and third trimesters. Materials and methods: A quasi-experimental pre-post test single group. A total of 40 pregnant women at low risk who were in their second and third trimester were included. Regarding the ethnical group all women were white. The 85% of pregnant women included had an age between 20 and 35 years and for the 60% it was their first pregnancy. Results: 60% of women have altered her sex life. The initially believed that the most suitable month to enjoy sex live more was on the second trimester, as shown on the first questionnaire (62.5%). After implementing the program, these results increased up to the 95%. Regarding the different sexual techniques, 87.5% knew them at first, after participating in our program this percentage increased to 97.4%. In relation to the benefits of Kegel exercises, in the first questionnaire only 25% knew the correct answer, while after the program increased to 85%. Its practice increased to 12.5% before the intervention, and then a 40% of pregnant women said they knew it and practiced it. Discussion-Conclusion: after applying our specific program noted some improvements in the level of knowledge and sexual attitudes but probably due to the small sample used was not found statistically significant results except for one variable (practice Kegel) (AU)


Subject(s)
Humans , Female , Pregnancy , Adult , Sex Education/methods , Sex Education/trends , Health Knowledge, Attitudes, Practice , Health Promotion/methods , Sex Education/organization & administration , Sex Education/standards , Surveys and Questionnaires , National Health Programs/organization & administration , National Health Programs/standards
12.
Transplant Proc ; 44(7): 2057-9, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22974908

ABSTRACT

OBJECTIVES: The aim of this study was to compare the evolution of the first kidney in relation to the second kidney transplanted from the same donor, focusing on the impact that a longer cold ischemia time may have as an independent variable. MATERIAL AND METHODS: The study included 44 pairs of kidneys transplanted from the same donor between February 2008 and October 2010, divided into Groups 1 and 2 according to the graft placement order. The variables analyzed were age, sex, comorbidities, number of transfusions, length of hospital stay, maximum peak PRA, immunologic incompatibility, ischemia time, delayed graft function (DGF), presence of rejection, creatinine clearance at first week, at 3 months and at 1 year, and vascular and tract complications in each group. RESULTS: The mean cold ischemia time was 15.6 hours in Group 1 and 20.1 hours in Group 2 (P < .001). The average recipient age was 52.79 years in Group 1 and 54.52 years in Group 2, with an equal sex ratio in the two groups; an average of 2.06 PRC were transfused prior to transplantation in Group 1 and 0.93 PRC in Group 2; the average length of stay was similar in the two groups. Major DR incompatibility was only found in Group 2 (P < .03). Creatinine clearance at first week, DGF and acute rejection showed worse results in Group 2, but these differences were not significant. Vascular complications were present in 4.5% and 2.3% of Groups 1 and 2, respectively, and tract complications were 6.8% and 11.4%. CONCLUSIONS: A greater tendency to DGF, early rejection and tract complications were found in the group with longer ischemia time, although the difference was not statistically significant. Larger series will be necessary to confirm our results.


Subject(s)
Kidney Transplantation , Tissue Donors , Blood Transfusion/statistics & numerical data , Female , Graft Rejection , Histocompatibility Testing , Humans , Kidney Function Tests , Length of Stay , Male , Middle Aged
13.
Metas enferm ; 14(5): 58-61, jun. 2011.
Article in Spanish | IBECS | ID: ibc-91359

ABSTRACT

La muerte perinatal es un proceso biológico que marcará la vida social,familiar y de pareja durante toda la vida y no es un proceso aisladoo que ocurra raras veces en la práctica asistencial, ya que tansolo en el primer semestre de 2010 se produjeron 744 muertes fetalestardías a nivel nacional. Por ello, algunos servicios de salud delas Comunidades Autónomas, como el de Andalucía, incluyen la“atención y apoyo al duelo perinatal” como uno de los objetivos acumplir por el profesional sanitario dentro del Proyecto de Humanizaciónde la Atención perinatal.La situación de duelo perinatal no es fácil de abordar para los profesionalessanitarios, por lo que con este trabajo se pretende proporcionara las enfermeras las herramientas básicas para poder abordarlos casos de duelo perinatal de manera efectiva en los primerosmomentos de su diagnóstico, describiendo cuáles son las principalescaracterísticas de este tipo de duelo y lo que es adecuado deciry hacer y lo que no, de manera que consigan ayudar a las familias ypuedan ayudarse a sí mismos mediante el control de sus emocionesy conductas (AU)


Perinatal death is a biological process that will mark the social, familyand intimate partner life of individuals who experience it throughouttheir entire lives. It is not an isolated or rare process in healthcaredelivery practice, as evidenced by the 744 late foetal deathsthat occurred in the first semester of 2010 nationwide. For this reason,some health services of certain Autonomous Communities,such as Andalucía, include “perinatal bereavement care and support”as one of the objectives to be met by the healthcare professionalwithin the framework of the Perinatal Care Humanization Project.Perinatal bereavement is not an easy situation for healthcare workersto approach, which is why this work aims to provide healthcare professionalswith the basic tools to effectively address perinatal bereavementin the first few moments following its diagnosis. To thisend, they are educated on the main characteristics of this type of bereavementand what should and should not be said and done, inorder to help families, and themselves, learn to manage their emotionsand behaviours (AU)


Subject(s)
Humans , Attitude to Death , Grief , Infant Mortality , Fetal Death , Pregnancy Outcome/psychology , Humanization of Assistance
14.
J Colloid Interface Sci ; 311(1): 253-61, 2007 Jul 01.
Article in English | MEDLINE | ID: mdl-17383669

ABSTRACT

Ionising radiation used for sterilization can have an effect on the physicochemical properties of pharmaceutically relevant excipient systems, affecting therefore the stability of the formulation. The effect of gamma irradiation on the phase behaviour (cloud point--CP) and critical micelle concentration (CMC) of aqueous solutions of Triton X-100, used as a model nonionic surfactant, is investigated in this paper. Micellar solutions were irradiated with gamma-rays in a dose range between 0 and 70 kGy, including the sterilization range of pharmaceutical preparations. The decreased observed in CP and CMC values of micellar solutions at all absorbed doses was explained in terms of changes in molecular mass distribution of ethoxylated surfactant and the formation of cross-linked species. These results were complemented by mass spectrometry, UV-vis and NMR spectroscopy. Although the findings indicate degradation of polyethoxylated chains by water radical attacks, there was no spectroscopic evidence of radiation damage to aromatic ring or hydrocarbon tail of surfactant. Models based on Flory-Huggins theory were employed to estimate CP from changes in mass distribution and to obtain cross-linking fractions. Surface tension measurements of non-irradiated and irradiated solutions were used for estimating the effectiveness and efficiency of surfactant in the formulation.


Subject(s)
Gamma Rays , Micelles , Octoxynol/chemistry , Octoxynol/radiation effects , Phase Transition/radiation effects , Solutions/chemistry , Solutions/radiation effects , Surface Properties , Water/chemistry
15.
Clin Genet ; 69(4): 297-305, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16630162

ABSTRACT

Machado-Joseph disease [MJD, also spinocerebellar ataxia type 3 (SCA3)] and familial amyloid polyneuropathy type I (FAP-I or ATTR V30M) are neurodegenerative disorders, inherited in an autosomal dominant fashion, which have a high prevalence in Portugal, probably due to a founder effect. MJD and FAP-I are late-onset diseases, with symptoms emerging usually during adulthood. CGPP, which is the national reference centre for these disorders, has a genetic lab that offers diagnostic, pre-symptomatic and prenatal testing and an outpatient clinic to counsel and follow relatives at risk for hereditary ataxias, FAP-I and Huntington disease (HD). The present work is a review of our 10-year experience with psychological counselling of individuals at risk for MJD and FAP-I. Persons at risk for FAP-I may show a better response to pre-symptomatic testing than those who are at risk for MJD and HD because of the availability of liver transplantation, which may improve their health and life expectancy. Psychological well-being and specific distress of MJD and FAP-I test applicants, before undergoing genetic testing (baseline level) and 3 to 6 months after disclosure of test results, have shown a low level of change, both in identified carriers and non-carriers. A major goal of psychological characterization of at-risk individuals for MJD and FAP-I is to determine the factors that influence the uptake of genetic testing.


Subject(s)
Amyloid Neuropathies, Familial/diagnosis , Genetic Counseling/psychology , Genetic Testing/psychology , Machado-Joseph Disease/diagnosis , Amyloid Neuropathies, Familial/genetics , Amyloid Neuropathies, Familial/psychology , DNA/analysis , DNA/genetics , Humans , Machado-Joseph Disease/genetics , Machado-Joseph Disease/psychology , Portugal , Risk Factors
16.
Chemistry ; 7(18): 3869-79, 2001 Sep 17.
Article in English | MEDLINE | ID: mdl-11596928

ABSTRACT

Compounds of rhodium(I) and rhodium(III) that contain ancillary hydrotris(pyrazolyl)borate ligands (Tp') react with monodentate and bidentate tertiary phosphanes in a step-wise manner, with incorporation of P-donor atoms and concomitant replacement of the Tp' pyrazolyl rings. Accordingly, [Rh(kappa3-TpMe2)(C2H4)(PMe3)] (1b), converts initially into [Rh(kappa2-TpMe2)-(PMe3)2] (3), and then into [Rh(kappa1-TpMe2)-(PMe3)3] (2) upon interaction with PMe3 at room temperature, in a process which can be readily reversed under appropriate experimental conditions. Full disengagement of the Tp' ligand is feasible to give Tp' salts of rhodium(I) complex cations, for example, [Rh(CO)(dppp)2]-[TpMe2,4-Cl] (5; dppp = Ph2P(CH2)3PPh2), or [Rh(dppp)2][TpMe2,4-Cl] (6). Bis(hydride) derivatives of rhodium(III) exhibit similar substitution chemistry, for instance, the neutral complex [Rh(Tp)-(H)2(PMe3)] reacts at 20 degrees C with an excess of PMe3 to give [Rh(H)2-(PMe3)4][Tp] (9b). Single-crystal X-ray studies of 9b, conducted at 143 K, demonstrate the absence of bonding interactions between the [Rh(H)2(PMe3)4]+ and Tp ions, the closest Rh...N contact being at 4.627 A.

17.
Proc Natl Acad Sci U S A ; 98(14): 8139-44, 2001 Jul 03.
Article in English | MEDLINE | ID: mdl-11416166

ABSTRACT

Hydroperoxide lyases (HPLs) catalyze the cleavage of fatty acid hydroperoxides to aldehydes and oxoacids. These volatile aldehydes play a major role in forming the aroma of many plant fruits and flowers. In addition, they have antimicrobial activity in vitro and thus are thought to be involved in the plant defense response against pest and pathogen attack. An HPL activity present in potato leaves has been characterized and shown to cleave specifically 13-hydroperoxides of both linoleic and linolenic acids to yield hexanal and 3-hexenal, respectively, and 12-oxo-dodecenoic acid. A cDNA encoding this HPL has been isolated and used to monitor gene expression in healthy and mechanically damaged potato plants. HPL gene expression is subject to developmental control, being high in young leaves and attenuated in older ones, and it is induced weakly by wounding. HPL enzymatic activity, nevertheless, remains constant in leaves of different ages and also after wounding, suggesting that posttranscriptional mechanisms may regulate its activity levels. Antisense-mediated HPL depletion in transgenic potato plants has identified this enzyme as a major route of 13-fatty acid hydroperoxide degradation in the leaves. Although these transgenic plants have highly reduced levels of both hexanal and 3-hexenal, they show no phenotypic differences compared with wild-type ones, particularly in regard to the expression of wound-induced genes. However, aphids feeding on the HPL-depleted plants display approximately a two-fold increase in fecundity above those feeding on nontransformed plants, consistent with the hypothesis that HPL-derived products have a negative impact on aphid performance. Thus, HPL-catalyzed production of C6 aldehydes may be a key step of a built-in resistance mechanism of plants against some sucking insect pests.


Subject(s)
Aldehyde-Lyases/genetics , Cytochrome P-450 Enzyme System/genetics , Solanum tuberosum/genetics , Aldehyde-Lyases/immunology , Aldehyde-Lyases/metabolism , Animals , Aphids , Cytochrome P-450 Enzyme System/immunology , Cytochrome P-450 Enzyme System/metabolism , Gene Expression Regulation, Plant/immunology , Molecular Sequence Data , Plant Diseases , Plants, Genetically Modified , Solanum tuberosum/immunology , Solanum tuberosum/metabolism
19.
Rev Neurol ; 30(2): 109-15, 2000.
Article in Spanish | MEDLINE | ID: mdl-10730314

ABSTRACT

INTRODUCTION: The prevalence of hereditary ataxia in Holguín, Cuba, is 43 per 100,000 inhabitants, but in some regions reaches 503 per 100,000 inhabitants, a figure never previously recorded in the international literature. OBJECTIVES: To evaluate the part played by non-cerebellar structures and vias in causing some of the clinical signs of the disorder by means of clinico-electro physiological correlation. PATIENTS AND METHODS: A neurological examination, peripheral nerve conduction studies and somato-sensorial evoked potentials of the median and posterior tibial nerves were done in 70 patients with type 2 spinocerebellar ataxia. RESULTS: The commonest clinical signs were ataxia on walking, dysarthria, dysmetria and adiadochokinesia. Correlation analysis showed that the variable most significantly correlated with the degree of ataxia and Romberg's sign was latency of the P40 component, whilst tendon reflexes were best correlated with H reflex latency. However, the duration of the disease was not found to have statistical correlation. CONCLUSIONS: These results suggest that degeneration of long peripheral nerves and sensory paths contributes to the degree of ataxia and other clinical signs. At present no correlation has been found between the duration of the illness and increasing electrophysiological changes, and therefore seems not to have a major effect on neurodegenerative mechanisms.


Subject(s)
Evoked Potentials, Somatosensory/physiology , Neural Conduction/physiology , Spinocerebellar Ataxias/diagnosis , Adolescent , Adult , Aged , Cerebellar Ataxia/diagnosis , Child , Child, Preschool , Cross-Sectional Studies , Cuba/epidemiology , Disease Progression , Dysarthria/diagnosis , Female , H-Reflex/physiology , Humans , Male , Middle Aged , Peripheral Nerves/physiology , Prevalence , Reflex, Stretch/physiology , Severity of Illness Index , Spinocerebellar Ataxias/epidemiology , Walking/physiology
20.
Rev. neurol ; 30(2): 109-115, 2000. tab, graf
Article in Spanish | CUMED | ID: cum-36376

ABSTRACT

The prevalence of hereditary ataxia in Holguín, Cuba, is 43 per 100,000 inhabitants, but in someregions reaches 503 per 100,000 inhabitants, a figure never previously recorded in the international literature. To evaluate the part played by non-cerebellar structures and vias in causing some of the clinical signs of the disorder by means ofclinico-electro physiological correlation. A neurological examination, peripheral nerve conductionstudies and somato-sensorial evoked potentials of the median and posterior tibial nerves were done in 70 patients with type 2spinocerebellar ataxia. The commonest clinical signs were ataxia on walking, dysarthria, dysmetria and adiadochokinesia.Correlation analysis showed that the variable most significantly correlated with the degree of ataxia and Rombergssign was latency of the P40 component, whilst tendon reflexes were best correlated with H reflex latency. However, the durationof the disease was not found to have statistical correlation. These results suggest that degeneration of longperipheral nerves and sensory paths contributes to the degree of ataxia and other clinical signs. At present no correlation hasbeen found between the duration of the illness and increasing electrophysiological changes, and therefore seems not to have amajor effect on neurodegenerative mechanisms...(AU)


Subject(s)
Humans , Ataxia , Spinocerebellar Ataxias , Electrophysiology
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