Inhibition of benzo[a]pyrene- and cyclophoshamide-induced mutagenicity by Cinnamomum cassia.

Cinnamomum cassia is used as a flavoring spice with some established medicinal properties. In this study, we evaluated the antimutagenic effect of C. cassia against two mutagens, viz. benzo[a]pyrene (B[a]P) and cyclophosphamide (CP). The antimutagenic properties of C. cassia were examined by the Ames test. In vivo chromosomal aberration (CA) and micronuclei tests were also employed to assess the antimutagenic effect of C. cassia in mice after pretreatment with the extract orally for seven consecutive days. To elucidate the mechanism by which C. cassia exerts its antimutagenic effect, certain key enzymes involved in bioactivation and detoxification processes were also investigated. Changes in liver cytochrome P450 (Cyt P450), glutathione content (GSH), glutathione S-transferase (GST), glutathione reductase (GR), and glutathione peroxidase (GPX) were evaluated in pretreated animals. It was observed in the Ames test, bone marrow chromosomal aberration assay, and micronucleus test that C. cassia exerted significant antimutagenic effects against B[a]P and CP in animals treated with the plant extract. C. cassia pretreatment decreased Cyt P450 content but increased GSH content and the activity of glutathione-dependent antioxidant enzymes, viz. GST, GR, and GPX. The present findings demonstrate that the antimutagenic potential of C. cassia could be attributed to its modulatory effect on the xenobiotic bioactivation and detoxification processes.

Factors that contribute to biomarker responses in humans including a study in individuals taking Vitamin C supplementation.

It is possible in many situations to identify humans exposed to potentially toxic materials in the workplace and in the environment. As in most human studies, there tends to be a high degree of interindividual variability in response to chemical insults. Some non-exposed control individuals exhibit as high a level of damage as some exposed individuals and some of these have levels of damage as low as many of the controls. Thus, it is only the mean values of the groups that can substantiate an exposure-related problem; the data on an individual basis are still of limited use. While human lymphocytes remain the most popular cell type for monitoring purposes, sperm, buccal, nasal, epithelial and placental cells are also used. However, for interpretation of responses, the issue of confounding factors must be addressed. There are endogenous confounding factors, such as age, gender, and genetic make-up and exogenous ones, including lifestyle habits (smoking, drinking, etc.) There are biomarkers of exposure, effect/response and susceptibility and the last may be influenced by the genotype and polymorphism genes existing in a population. From our own studies, confounding effects on cytogenetic damage and ras oncoproteins will be considered in relation to workers exposed to vinyl chloride and petroleum emissions and to volunteers taking Vitamin C supplementation. Smoking history, exposure and duration of employment affected the worker studies. For petroleum emissions, so did gender and season of exposure. For the non-smoking volunteer Vitamin C supplementation study, cholesterol levels, plasma Vitamin C levels, lipid peroxidation products and DNA damage in the Comet assay were also measured. Gender affected differences in Vitamin C levels, antioxidant capacity and the number of chromosome aberrations induced by bleomycin challenge in vitro. The results were the same for both high and low cholesterol subjects. The relationship between biomarkers and the various factors which affect them is complex. Sometimes the variables are not completely independent of each other.

Cryopreservation of ICR mouse oocytes: improved post-thawed preimplantation development after vitrification using Taxol, a cytoskeleton stabilizer.

OBJECTIVE: To establish an effective cryopreservation method. DESIGN: In vitro model study. SETTING: Infertility Medical Center, Pochon CHA University. ANIMAL(S): Four-week-old ICR mice superovulated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin. INTERVENTION(S): Vitrified-thawed oocytes were fertilized and subsequently cultured in vitro. MAIN OUTCOME MEASURE(S): Post-thawed development, chromosome/spindle normalities, and blastocyst quality. RESULT(S): More cumulus-enclosed oocytes were fertilized and developed to the 8-cell stage after vitrification and thawing than denuded oocytes. However, cryopreserved oocytes of both types had lower spindle and chromosome normalities than fresh oocytes, which resulted in reduced developmental competence after thawing. The addition of 1 microM of Taxol, a cytoskeleton stabilizer, to vitrification solution greatly promoted the blastocyst formation of vitrified-thawed oocytes, compared with no addition (24.0% vs. 58.6%). No difference in blastocyst quality, which was evaluated by blastomere and inner cell mass cell numbers and inner cell mass cell per trophoblast ratio, was found between fresh oocytes and oocytes vitrified with Taxol. CONCLUSION(S): A vitrification solution consisting of 5.5 M ethylene glycol, 1.0 M sucrose, 10% fetal bovine serum, and 1 microM Taxol greatly improved post-thawed development of vitrified oocytes.

Marcadores bioquímicos para la detección de cromosopatías y defectos del cierre del tubo neural en el feto / Biochemical markers for chromosopathies detection and defects in fetal neural tube closure

Aunque las malformaciones congénitas, las enfermedades cromosómicas y hereditarias son de presentación infrecuente, en forma conjunta contribuyen a una porción significativa de la morbimortalidad perinatal e infantil. La alfa fetoproteína (AFP) fue el primer marcador bioquímico de anomalías cromosómicas o estructuras fetales, identificado en sangre materna. Utilizada entre las semanas 16 y 20 de gestación, y tomando un punto de corte de 2MoM (múltiplos de la mediana para cada edad gestacional) la tasa de detección para anencefalia fue de 93 por ciento, y para espina bífida 85 por ciento con una tasa de falsos positivos de 8 por ciento. El descubrimiento de nuevos marcadores: estriol no congugado (uE3), la beta subunidad de la hormona gonadotrofina coriónica humana (b hCG), y la inhibina A, permitieron una mejora en las tasas de detección. La utilización de marcadores múltiples en el segundo trimestre permite una detección del 60-70 por ciento de los fetos afectados con una trisomía 21 con una tasa de falsos positivos del 5 por ciento; y permite además la detección del 98 por ciento de los defectos abiertos del cierre del tubo neural. Recientemente se han hallado marcadores bioquímicos (fracción libre de la b h CG y PAPP A-pregnancy associated plasma protein A) y ecográficos (pliegue nucal) útiles en el primer trimestre (11-13 semanas), cuyo uso conjunto permiten, en algunos centros, una detección de hasta un 90 por ciento de los casos. Todo programa de screening prenatal debe poseer la capacidad de disminuir la morbilidad y la mortalidad, permitiendo el acceso al diagnóstico prenatal y estimulando en las parejas la capacidad de tomar decisiones informadas sobre su reproducción así como diseñar estrategias adecuadas para el seguimiento del embarazo y el parto

Marcadores bioquímicos para la detección de cromosopatías y defectos del cierre del tubo neural en el feto / Biochemical markers for chromosopathies detection and defects in fetal neural tube closure

Aunque las malformaciones congénitas, las enfermedades cromosómicas y hereditarias son de presentación infrecuente, en forma conjunta contribuyen a una porción significativa de la morbimortalidad perinatal e infantil. La alfa fetoproteína (AFP) fue el primer marcador bioquímico de anomalías cromosómicas o estructuras fetales, identificado en sangre materna. Utilizada entre las semanas 16 y 20 de gestación, y tomando un punto de corte de 2MoM (múltiplos de la mediana para cada edad gestacional) la tasa de detección para anencefalia fue de 93 por ciento, y para espina bífida 85 por ciento con una tasa de falsos positivos de 8 por ciento. El descubrimiento de nuevos marcadores: estriol no congugado (uE3), la beta subunidad de la hormona gonadotrofina coriónica humana (b hCG), y la inhibina A, permitieron una mejora en las tasas de detección. La utilización de marcadores múltiples en el segundo trimestre permite una detección del 60-70 por ciento de los fetos afectados con una trisomía 21 con una tasa de falsos positivos del 5 por ciento; y permite además la detección del 98 por ciento de los defectos abiertos del cierre del tubo neural. Recientemente se han hallado marcadores bioquímicos (fracción libre de la b h CG y PAPP A-pregnancy associated plasma protein A) y ecográficos (pliegue nucal) útiles en el primer trimestre (11-13 semanas), cuyo uso conjunto permiten, en algunos centros, una detección de hasta un 90 por ciento de los casos. Todo programa de screening prenatal debe poseer la capacidad de disminuir la morbilidad y la mortalidad, permitiendo el acceso al diagnóstico prenatal y estimulando en las parejas la capacidad de tomar decisiones informadas sobre su reproducción así como diseñar estrategias adecuadas para el seguimiento del embarazo y el parto

The impact of molecular genetics on oral health paradigms.

As a result of our increased understanding of the human genome, and the functional interrelationships of gene products with each other and with the environment, it is becoming increasingly evident that many human diseases are influenced by heritable alterations in the structure or function of genes. Significant advances in research methods and newly emerging partnerships between private and public sector interests are creating new possibilities for utilization of genetic information for the diagnosis and treatment of human diseases. The availability and application of genetic information to the understanding of normal and abnormal human growth and development are fundamentally changing the way we approach the study of human diseases. As a result, the issues and principles of medical genetics are coming to bear across all disciplines of health care. In this review, we discuss some of the potential applications of human molecular genetics for the diagnosis and treatment of oral diseases. This discussion is presented in the context of the ongoing technological advances and conceptual changes that are occurring in the field of medical genetics. To realize the promise of this new molecular genetics, we must be prepared to foresee the possibilities and to incorporate these newly emergent technologies into the evolving discipline of dentistry. By using examples of human conditions, we illustrate the broad application of this emerging technology to the study of simple as well as complex genetic diseases. Throughout this paper, we will use the following terminology: Penetrance--In a population, defined as the proportion of individuals possessing a disease-causing genotype who express the disease phenotype. When this proportion is less than 100%, the disease is said to have reduced or incomplete penetrance. Polymerase chain reaction (PCR)--A technique for amplifying a large number of copies of a specific DNA sequence flanked by two oligonucleotide primers. The DNA is alternately heated and cooled in the presence of DNA polymerase and free nucleotides, so that the specified DNA segment is denatured, hybridized with primers, and extended by DNA polymerase. MIM--Mendelian Inheritance in Man catalogue number from V. McKusick's Mendelian Inheritance in man (OMIM, 1998).

Quality of life in Turner syndrome is related to chromosomal constitution: implications for genetic counselling and management.

Issues of self-appraisal, friendships and academic attainments are uniquely salient for all adolescents. For girls with Turner syndrome, social problems and learning difficulties often become more serious at this time, yet may be unacknowledged by those responsible for paediatric care because their focus is on growth and sexual maturation. Data on the social and educational adjustment of 110 45,X (monosomic) females aged between 6 and 25 years is presented. Detailed information on the patients' precise karyotype was used to demonstrate systematic differences in adjustment between those whose single X chromosome was maternally derived and those in whom it was paternal. Implications for educational support and parental guidance are discussed.

A diagnostic clinical genetic study of craniofacial dysmorphism.

A diagnostic evaluation of craniofacial anomalies, either isolated or as part of a genetic syndrome was conducted on 25 patients (8 females, 17 males), age range 2 months to 47 years. Complete genetic examination, pedigree analysis, anthropometric measurements and radiological studies were carried out. Cytogenetic studies included fluorescence in situ hybridization (FISH) when indicated. In all, 15 patients had chromosomal abnormalities. Five patients had unbalanced chromosome rearrangements and six had chromosome markers. Three patients were FISH-positive for William syndrome and one was positive for Prader-Willi syndrome. Ten patients had monogenic disorders. Five were diagnosed as craniosynostosis syndromes. We conclude that minor features are useful for making a diagnosis of congenital anomalies.

Empowering individuals in the prevention of genetic disease.

As the International Human Genome Project nears the term of a long gestation, the ethical and social implications of complex new genetic technologies will require a new breed of clinicians for a safe delivery. Clinical genetic care has been time intensive as performed by medical specialists. Empowering individuals to take advantage of new opportunities for genetic testing to prevent disease will require clinician education and decision support in the context of individual values.

[Genetic diagnosis of IVF embryos: preliminary results from 'preimplantation genetic diagnoses' in the Netherlands]. / Genetische diagnostiek bij IVF-embryo's: eerste ervaringen met 'preïmplantatiegenetische diagnostiek' in Nederland.

Preimplantation genetic diagnosis (PGD) is a very early form of genetic testing. It involves testing one or two cells taken from a recent embryo of eight cells produced by in vitro fertilization, and selective transfer of genetically normal embryos. So far in the Academic Hospital Maastricht, the Netherlands, 20 couples have undergone PGD, resulting in 6 ongoing pregnancies (one twin pregnancy). In three women the indications for PGD were: cystic fibrosis, sex-linked Pelizaeus-Merzbacher disease and chromosomal translocation, respectively. In the Netherlands PGD is only allowed if there is a high risk of a serious genetic disease. PGD can be carried out in Maastricht for: cystic fibrosis, sex-linked diseases, chromosomal abnormalities, fragile X syndrome, spinal muscular atrophy and myotonic dystrophy. The advantage of PGD is that it excludes the necessity of a therapeutic abortion. Disadvantages ages are the requirement of in vitro fertilization, which has only a 15-20% pregnancy rate, and the experimental nature of the PGD procedure. To date, about 200 children have been born worldwide following PGD.

Perinatal hospice: a response to partial birth abortion for infants with congenital defects.

This article discusses decisions involving whether to terminate late-term pregnancies when fetal anomalies have been detected. Partial-birth abortion performed on fetuses with chromosomal abnormalities, while performed under the guise of reducing suffering, threatens the best interests of the mother and infant. An alternative for parents faced with the decision to terminate their pregnancy is perinatal hospice. Perinatal hospice recognizes the value of bringing these infants to term by treating them as beings conceived with a tangible future. This alternative is preferred because of post-termination psychological distress and because biblical teachings emphasize the dignity and worth of each fetus. Perinatal hospice supports parents through their grief when their infant dies and maximizes the opportunity for authentic mourning.

[Pregnancy following oocyte donation]. / Zwangerschap na eiceldonatie.

Five women, aged 31, 26, 31, 34, and 28 years, became pregnant after oocyte donation and in-vitro fertilization. One was a carrier of Leber's optical atrophy, three had had an early menopause (in two because of chromosomal abnormalities), and one had had bilateral ovarian extirpation because of a cystadenoma and endometriosis. Three developed (pre-)eclampsia during pregnancy and one had a serious fluxus post partum. One twin died in utero, the other children were healthy. In the Netherlands in-vitro fertilization (with or without egg-donation) takes place up to the age of about 40. Regarding the high incidence of obstetrical complications in women under 40, raising the age limit could lead to even more pregnancy problems. Candidates for oocyte donation should be informed about these risks, furthermore they should not deliver at home.

Can preference scores for discrete states be used to derive preference scores for an entire path of events? An application to prenatal diagnosis.

The authors conducted a study exploring whether preferences for sequences of events can be approximated by preferences for component discrete states. Visual-analog-scale (VAS) and standard-gamble (SG) scores for a subset of the possible sequences of events (path states) and component temporary and chronic outcomes (discrete states) that can follow prenatal diagnostic decisions were elicited from 121 pregnant women facing a choice between chorionic villus sampling and amniocentesis. For individuals, preference scores for path states could not be predicted easily from discrete-state scores. Mean path-state VAS scores, however, were predicted reasonably accurately by multiple regression models (R2 = 0.85 and 0.82 for two different anchoring schemes), with most measured scores lying within the 95% confidence intervals of the derived scores. It is concluded that, for individual patient decision making, preferences for path states should be elicited. When mean preference values for a population are sought, however, it may be reasonable to derive regression weights from a subset of respondents and then to apply those weights to preferences for discrete states elicited from a larger group.

[Value of a genetic evaluation before an intracytoplasmic sperm injection procedure]. / Intérêt d'une évaluation génétique lors d'une procédure d'ICSI.

Intracytoplasmic sperm injection (ICSI) still needs to be validated as far as safety is concerned. Results concerning foetal karyotypes currently seem to show an increase in sexual chromosomal abnormalities. In view of the heterogeneity of publications concerning genetic tests, it seems necessary to define a protocol with a limited time span, which will allow the extensive collection of data. The analysis of the results will secondarily allow a common procedure to be established. We propose a protocol limited in time, aiming to evaluate the chromosomal status at birth by a systematic karyotype of umbilical cord blood.