bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic Services to the Latino Population in the United States
Authors: Penchaszadeh VictorB. , Puñales-Morejón Diana
Published: April 2003

In 1998 Latinos (Hispanics) in the United States number 30 million persons and account for 11.3% of the total population, while it is predicted that by the year 2020 they will become the largest minority. This article describes the demographics and health profile of the Latino population in the United States. A brief account is given of common cultural traditions and health beliefs that modulate the interaction of this population with the health delivery system in general, and that of genetic services in particular. Further, some problems in the access to, and utilization of genetic services are outlined, and the experience of a project designed to overcome those problems in New York City is described.
The Difficulties of Recruiting Minorities to Studies of Ethics and Values in Genetics
Authors: Wertz DorothyC.
Published: April 2003

There are proportionately fewer members of minority groups among genetics services providers (including Master’s level counselors) than in other US medical specialties. Although no national data exist on race and sex of genetics patients, most respondents to a general survey of patients’ ethical views were white (89%). The added cost of adequately sampling ‘low-incidence’ minority groups makes adequate inclusion difficult. In a general public survey of 1,000 persons, African Americans (11%) differed from the larger group on 52% of ethical questions. Generally, they were less concerned about individual privacy and more concerned about welfare of partners and relatives, preferred somewhat more directive counseling, were less concerned about autonomy and adoptees’ rights to information, were more likely to use the ‘don’t know’ response in regard to new reproductive technologies, and were less accepting of abortion for congenital conditions.
Epidemiology of Usher Syndrome in Valencia and Spain
Authors: Espinós C. , Millán J.M. , Beneyto M. , Nájera C.
Published: April 2003

Objective: To obtain epidemiological data on the prevalence of the different types of Usher syndrome (US) in Spain, since these data were missing; to estimate the proportion of sporadic cases among simplex families, and calculate the prevalence of the Usher syndrome in a homogeneous population from Eastern Spain (3,875,234 inhabitants) that is representative of the Spanish population. Methods: Otological, ophthalmological and genetic studies were performed in 89 US patients from 46 families and subjected to statistical and segregation analysis. Results: 41.6% of them suffered US type I, 46.1% type II, and in 12.3% the classification remains unclear. The estimated prevalence for the Province of Valencia was 4.2/100,000. There was a notable excess of male-only affected multiplex sibships in our sample that could be attributable to an X-linked inheritance. Conclusions: The number of families with USI type was similar to that of families with USII type. The estimated prevalence for the Province of Valencia is in agreement with other reports in which the estimate for the prevalence of US ranges from 1.8 to 6.2/100,000.
The Molecular Spectrum of Beta-Thalassemia and Abnormal Hemoglobins in the Allochthonous and Autochthonous Dutch Population
Authors: Giordano Piero C. , Harteveld Cees L. , Heister Angelien J.G.M. , Batelaan Desirée , van Delft Peter , Plug Rob , Losekoot Monique , Bernini Luigi F.
Published: April 2003

The prevalence at birth of hemoglobin defects in the autochthonous North-European population is low. However, the long immigration and colonial history of the Netherlands has resulted in a group of about 1–2 million ‘autochthonous‘ inhabitants, with Asian, South-European or African ancestors, in whom a moderate birth prevalence of globin gene mutations can be expected. Furthermore, at least 10% of the Dutch population consists of recent immigrants from different countries with high birth prevalence of hemoglobinopathies. Because of the endogamous partner choice, which is prevalent in this population, the risk for homozygous progeny remains elevated. At least 100,000 carriers of hemoglobinopathies of recent allochthonous origin are present in the Netherlands, and the number of homozygous children is rising. Prevention by prenatal diagnosis requires a suitable protocol and knowledge about the molecular defects present in the country. Therefore we have analyzed a large number of patients and carriers, both at the hematological and at the DNA level. Our survey revealed 47 different β-thalassemia determinants, characterized on 223 independent chromosomes from individuals of different ethnic origins. As expected, the most prevalent mutations were largely represented. The cd39 (C→T) mutation was found in 70% of the immigrants from Morocco, Sardinia and other Central-West-Mediterranean regions while the IVS-I-110 (G→A) was prevalent in the East-Mediterranean populations. The IVS-I-5 (G→C) mutation was found in 45% of the patients of Indonesian origin. We also registered 308 independent chromosomes with common structural defects (HbS, HbC, HbE, Hb Lepore, Hb Constant Spring and HbD Punjab) and 33 chromosomes with 19 different, less frequent, rare or very rare mutants. Seven structural mutants were described for the first time and published separately. Furthermore, 139 independent chromosomes with deletional and nondeletional α-thalassemia defects were characterized.
Knowledge about Medical Genetics in Health Care
Authors: Harris Rodney , Harris Hilary
Published: April 2003

Effective genetic services depend upon co-operation between medical geneticists and many different non-geneticist professionals to ensure that the most appropriate patients are referred to geneticists and that those that require long-term care receive it. Important determinants of the quality of genetic services are the knowledge that professionals have about clinical genetics and the equitable distribution of adequately resourced genetic centres. Consequently, we have investigated in a European context how much clinically relevant genetics non-geneticists know, how competent non-geneticists are in counselling their own patients, how well equipped specialist genetic centres are, who refers to genetic centres and what they refer and who offers continuing care to patients and families whose problems are not resolvable at a limited genetic clinic visit.
Common Language for Measures of Occurrence of Congenital Anomalies and Genetic Diseases: Incidence or Birth Prevalence
Authors: Cornel Martina C.
Published: April 2003

Scientists involved in the epidemiology of congenital anomalies (including genetic diseases) use many terms to describe the occurrence of these disorders amongst births, such as ‘incidence’, ‘prevalence’ and ‘rate’. Yet it is clear that often ’prevalence’ is the only meaningful measure for the proportion of births affected with a certain congenital or genetic disorder. ‘Incidence’ and ‘rate’ are usually inappropriate, as the assessment of the frequency of a disorder is not a matter of following up a cohort of healthy individuals until they fall ill.
French Physicians’ Knowledge about Hereditary Breast/Ovarian Cancer: The Need for Continuing Vocational Training in Genetics
Authors: Julian-Reynier Claire , Eisinger François , Moatti Jean-Paul , Sobol Hagay
Published: April 2003

Objectives: The aim of this study was to determine what medical specialists knew about recent findings in the genetics of breast/ovarian cancer, according to their speciality and the methods they used to keep themselves up to date. Methods: A national random sample of 1,169 surgeons and gynaeco-obstetricians was surveyed using a mailed questionnaire, to which 700 of those contacted responded (60%). Results: Two years after it had been identified, BRCA1 was known by only 54% of the practitioners, whereas BRCA2 was known by 49.1% 1 year after it was first identified. The lifetime breast cancer risk of women in the general population was estimated by 37.6% of the participants to be between 6 and 10%, and 35.7% rated the penetrance of a breast cancer mutated gene at between 70 and 90%. After multivariate adjustment, the overall score for knowledge of hereditary breast/ovarian cancer was mainly determined as follows: by the speciality (p < 0.001), since the gynaeco-obstetricians scored the highest and the general surgeons the lowest; by the size of practice (p < 0.001), since a larger practice was associated with a higher score, and by whether or not the participants were accustomed to reading the international literature (p < 0.01). Conclusions: These results show the need for physicians who are not geneticists to acquire further knowledge about cancer genetics. We discuss the role of international reviews in communicating the latest knowledge available in genetics to specialists working in other medical fields.
Prenatal Genetic Testing in Japan
Authors: Matsuda Ichiro , Suzumori Kaoru
Published: April 2003

Objective: To examine the use of prenatal diagnosis and maternal serum maker tests (MSMTs) from January 1 to December 31, 1997, in Japan.  Methods: Questionnaires were sent to medical facilities, which represent about 80% of the facilities providing prenatal diagnosis. Results: Prenatal diagnosis was performed in 5,748 women, of whom 5,538 (5,516 amniocenteses and 22 chorionic villus sampling; 96.3%) were screened for chromosomal abnormalities. 89.1% (221/248) of those diagnosed to have fetal abnormalities terminated the pregnancy. Written informed consent signed by both the obstetrician and the pregnant woman undergoing prenatal diagnosis was the policy in 76.5% facilities. A total of 14,682 MSMTs were performed: 8,919 were in pregnant women under 34 years of age and 5,763 were in women aged 35 years or older. Follow-up data were obtained in 10,209; 6,918 women under 34 years were tested; of those 448 had a positive result; 349 underwent amniocentesis and trisomy 21 was diagnosed in 9. 3,291 women aged 35 years or older were tested; of those 634 had a positive result; 607 underwent amniocentesis and trisomy 21 was found in 16 cases. Written informed consent before MSMTs was obtained in 34.5% of the facilities. Conclusion: The data showed that only 4% of pregnant women above age 35 years underwent amniocentesis in Japan, and a small proportion of pregnant women were being offered MSMTs. Prenatal testing should be carried out only on a voluntary basis. For this purpose, women must be adequately informed.
Identification of Human Serum Albumin in Human Caries Lesions of Enamel: The Role of Putative Inhibitors of Remineralisation
Authors: Robinson C. , Shore R.  C. , Bonass W.  A. , Brookes S.  J. , Boteva E. , Kirkham J.
Published: April 2003

Carious attack on enamel is not a unidirectional process but involves both demineralisation and remineralisation. The chemistry of carious attack on enamel has, to a large extent, now been clarified as far as mineral components are concerned but little attention, however, has been paid to the identity of organic material in carious lesions and its possible role in the caries process. The only clear information available is that organic material accumulates with time within enamel lesions. The present study was aimed at identifying a specific protein component known to bind to hydroxyapatite (albumin) in carious lesions with a view to investigating its role in the disease process. The distribution of albumin within both white spot and fissure lesions and adjacent sound enamel of extracted human teeth was investigated using SEM immunohistochemistry on undemineralised sections of human enamel and employing a polyclonal antibody to human serum albumin. The nature of the protein, i.e. whether it was in the form of intact molecules or degraded fragments, was investigated by Western blotting, employing the same antibody. The immunohistochemistry revealed the presence of albumin within both interproximal white spot and fissure lesions with little if any present in sound enamel. The Western blotting indicated that the albumin was in the intact form with no evidence of degradation products. The ability of albumin to bind and to inhibit growth of calcium phosphate crystals raises the question as to the possible role of such a molecule in the development of carious lesions.
Fluoride Distribution in Sound and Carious Root Tissues of Human Teeth
Authors: Shu M. , Pearce E.  I.  F. , Sissons C.H. , Coote G.E. , Miller J.  H.
Published: April 2003

Proton probe analysis has been used to provide for the first time quantitative F concentration data in carious root tissues from subjects consuming water containing 1 ppm F. In small lesions at the neck of the tooth with minimal tissue loss the F concentration was significantly higher at the outer lesion edge than at the outer edge of adjacent sound root tissue. In one sample with high F values the lesion edge had 19,000 ppm F and the adjacent sound root surface 5,400 ppm F (μg F/g apatite). In large lesions with extensive cavitation F was again concentrated in the outer edge of the lesion and was significantly higher (1,800–4,100 ppm) than in adjacent sound inner dentine (190–290 ppm). Fluoride concentrations varied markedly along the outer edge of both normal and carious root tissues. Fluoride increase at the lesion edge is not an effect of tissue shrinkage but probably a result of remineralisation events during caries. This additional F may be expected to increase tissue resistance to further acid attacks.
Phosphoprotein Analysis of Sequential Extracts of Human Dentin and the Determination of the Subsequent Remineralization Potential of these Dentin Matrices
Authors: Clarkson B.H. , Chang S.R. , Holland G.R.
Published: April 2003

Phosphoprotein appears to play an important role in the mineralization of dentin during tooth development and remineralization after demineralization by dental caries. To better understand this role, we describe the extraction and characterization of phosphoprotein from immature, human root apex dentin during and after EDTA demineralization. The extraction procedure included dissociation of the demineralized dentin matrix by guanidine hydrochloride (Gdn·HCl) followed by subsequent digestion with cyanogen bromide (CNBr) and collagenase. Characterization of these extracts included 'Stains–All' staining of SDS polyacrylamide gels (SDS–PAGE) and amino acid, protein and phosphorus analyses. The ability of these matrices to remineralize was determined by TEM and measuring calcium levels in the remineralized tissue by atomic absorption spectroscopy. The staining of SDS–PAGE gels and amino acid analysis showed that an intact phosphophoryn was extracted from the dentin of the immature apices during EDTA demineralization and that it had an apparent Mr∼140,000. In the subsequent extracts and digests, the phosphoprotein has a range of molecular weights, some of which may have been degraded products of the intact phosphoprotein. A greater quantity of phosphoprotein was found in the EDTA–demineralized dentin matrices than in dentin after Gdn·HCl, CNBr and collagenase digests. These EDTA–demineralized matrices also remineralized to a greater extent than those dissociated with Gdn·HCl. The differences in both the quantity and the quality, as defined by the amino acid residue profile, of the phosphoprotein in the sequential extracts of the root apex dentin may be important in affecting the ability of this tissue to remineralize.
Fluoride Uptake to Demineralised Enamel: A Comparison of Sampling Techniques
Authors: Duckworth R.M. , Lynch R.J.M.
Published: April 2003

Fluoride uptake is a recognised way of assessing the potential anticaries efficacy of fluoride (F) treatments. The aim of the present study was to compare an abrasion method of sampling treated enamel, based on that of Weatherell et al. [Caries Res 1985;19:97–102], with the acid–etch method of Raven et al. [Caries Res 1991;25:130–137]. Two adjacent demineralised areas were created on the polished surfaces of bovine incisors using an acid gel system. One artificial lesion from each tooth was subsequently treated for 6 h at 37°C with one of two fluoridated dentifrice slurries (1 part: 3 parts water), whereas the other was treated similarly with a slurry of non–F control dentifrice. One set of treated lesions was then separated, the base of each enamel block polished until planoparallel with the demineralised surface and the lesions isolated by cutting away the adjacent sound enamel. Each block was mounted on the probe of a digital micrometer and the demineralised surface abraded with silicon carbide lapping film until sound material was reached. Abraded material was dissolved in perchloric acid and the buffered solution analysed for fluoride by ion–selective electrode. Each lesion of a second set of treated, demineralised enamel blocks was etched by 20μl acid and the resulting solutions analysed for F. Mean F uptakes [μg cm–2 (SD)] were: abrasion (n = 7/treatment); F dentifrice A = 1.39 (0.89) and B = 0.86 (0.45) relative to non–F controls = 0.11 (0.12), 0.14 (0.06), respectively; and acid–etch (n = 14/treatment); A = 1.27 (0.49), B = 0.69 (0.23), controls = 0.12 (0.06), 0.12 (0.06), respectively. Significant differences (p<0.05) for both data sets were: A>B> control. The results show good agreement between the sampling methods and demonstrate the ability of the abrasion technique to distinguish between F treatments.
A Comparison of Increment and Incidence Density Analyses in Evaluating the Anticaries Effects of Two Dentifrices
Authors: Caplan D.J. , Slade G.D. , Biesbrock A.R. , Bartizek R.D. , McClanahan St.F. , Beck J.D.
Published: April 2003

This study aimed to determine whether incidence density (ID) calculations of caries incidence rates would provide a more sensitive means of detecting caries–preventive effects than would traditional techniques. A secondary analysis was conducted using data from a 1981 study in which three dentifrices were compared in a double–blind randomized clinical trial. Subjects were examined at baseline and 1, 2 and 3 years after baseline. Three–year DMFS increments were calculated for 1,754 subjects attending the baseline and 3–year examinations. Caries ID rates then were calculated for 2,661 subjects who had at least two examinations, using each surface's net increment (–1, 0 or +1) as the numerator and the surface's time at risk as the denominator. Despite theoretical advantages, the ID method did not alter the conclusions drawn using DMFS increments, apparently because (a) subjects lost to follow–up were similar to those completing the study, and (b) loss to follow–up was similar among treatment groups.
Influence of Acidified Fluoride Gel on Abrasion Resistance of Eroded Enamel
Authors: Attin T. , Deifuss H. , Hellwig E.
Published: April 2003

The objective of the study was to evaluate the abrasion resistance of eroded enamel brushed with an acidified fluoride gel. Each enamel specimen was prepared from one of 64 bovine incisors. The specimens were embedded in acrylic resin, ground flat, polished and subsequently covered with a tape exposing an area of 1.8×10.0 mm in the center of the enamel specimens. The samples were alternatingly stored in a demineralizing solution (5 min) and a remineralizing solution (1min) four times. An acidic soft drink (Sprite Light®) served as a demineralizing solution and artificial saliva was used as a remineralizing solution. After each remineralization the specimens were brushed in an automatic brushing machine (2,000 strokes, 2.5 N load) and subsequently stored again in saliva (1 min). A mixture of artificial saliva (5 ml) with a gel (1 ml) based on the formulation of Elmex® gelée (Wybert, Lörrach, Germany) served as an abrasive slurry. Thirty seconds after brushing, the slurry was removed from the specimens by rinsing with destilled water. For each of 16 specimens the following gels (A–D) were used: gels A (pH 7.0) and B (pH 4.5) were unfluoridated; gels C (pH 7.0) and D (Elmex gelée; pH 4.5) contained 1.25% F–. After two cycles the specimens were kept in the saliva for 8 h. Finally the tape was removed and the abrasion was determined profilometrically. The following values (mean ± SD) were obtained and statistically analyzed by analysis of variance and Wilcoxon two–sample tests (p≤0.01): gel A, 0.96±0.24 μm; B, 1.58±0.32 μm; C, 0.71±0.23 μm; D, 0.25±0.08 μm. The differences between all experimental groups were statistically significant. It is assumed that treatment of enamel erosions with an acidified fluoride gel results in a higher abrasion resistance compared to gels which are either unfluoridated or neutral.
The Influence of Specific Foods and Oral Hygiene on the Microflora of Fissures and Smooth Surfaces of Molar Teeth: A 5–Day Study
Authors: Beighton D. , Brailsford S.R. , Lynch E. , Yuan Chen H. , Clark D.T.
Published: April 2003

A group of 20 students, harbouring >104 mutans streptococci per millilitre of saliva, was enrolled into the study. Models for sampling, reproducibly, the dental plaque present in specific sites (fissure and smooth surface) on the dentition were developed and validated. Withdrawal of normal oral hygiene procedures for only 1 day resulted in approximately 10–fold increases in the number of micro–organisms recovered from both sites. The effect of supplementing the subjects’ diets with particular food items given 5 times per day [lemonade (5.8% w/v sugars, 250 ml), biscuits (digestive biscuits, 67.6% w/w carbohydrate of which 22% w/w was sugars and 45.6% w/w was starch), caramel toffees and sugar lumps] on the number of micro–organisms recovered and on the composition of the flora at both sites was determined. Dental plaque samples were taken after 5 days and it was found that supplementation of the diet with toffee and sugar lumps resulted in significantly more micro–organisms at both sampling sites. The supplementation of the diets with lemonade or biscuits did not significantly alter the numbers of micro–organisms recovered from either site. The percentage composition of the plaque samples from both dental sites remained relatively unaffected by oral hygiene although there were lower levels of mutans streptococci which might be related to the use of an antimicrobial toothpaste containing fluoride, triclosan and zinc citrate. This study suggests that the cariogenicity of certain sucrose–containing foods may, in part, be due to the enhancement of plaque accumulation in addition to other effects on the percentage composition of the plaque which may become manifest on prolonged usage of these dietary foodstuffs. These observations are consistent with dietary survey findings which often find consumption of confectionery related to caries experience or incidence.
Toothbrush Abrasion of Erosively Altered Enamel after Intraoral Exposure to Saliva: An in situ Study
Authors: Jaeggi T. , Lussi A.
Published: April 2003

The aim of this in situ study was to test the effect of toothbrush abrasion on enamel previously exposed to a standardized artifical erosive agent. To generate moderate erosive lesions, slabs of the buccal surface of human premolars were immersed in a solution of citric acid for 3 min. Then they were attached to intraoral appliances and each one was exposed for 0 min (= toothbrushing immediately after intraoral exposure), 30 or 60 min to the oral milieu of 1 of 7 female subjects with a mean age of 22 years. Immediately thereafter the volunteers brushed the slabs for 30 s with toothpaste using their preferred brushing technique. For each test person the secretion rate of resting and paraffin–stimulated saliva, buffering capacity and pH were measured. The following mean losses of substance at the surface were registered: 0.258±0.141 μm (toothbrushing immediately after intraoral exposure), 0.224±0.087 μm (toothbrushing after intraoral exposure of 30 min) and 0.195±0.075 μm (toothbrushing after intraoral exposure of 60 min). Toothbrush abrasion in situ was significantly lower after 60–min exposure to the oral environment than after 0–min (p<0.001). Also, the 30– and 60–min values were significantly different from each other (p<0.001). Multiple linear regression analyses revealed that in this model toothbrush abrasion was associated with the intraoral exposure to saliva (p = 0.026), the severity of the erosive attack (p<0.001) and the secretion rate of resting saliva (p = 0.029). If no other preventive measures are taken we suggest that individuals at risk for erosive tooth wear wait at least 1 h before brushing their teeth after consuming erosive foodstuffs or beverages.
Distribution of Exogenous Proteins in Caries Lesions in Relation to the Pattern of Demineralisation
Authors: Shore R.C. , Kirkham J. , Brookes S.J. , Wood S.R. , Robinson C.
Published: April 2003

While it is believed that proteins may protect enamel from demineralisation, recent work has indicated that such material may also hinder remineralisation. For example, albumin will inhibit apatite crystal growth in vitro and is present in carious enamel in vivo. However, it is not clear whether (1) the distribution of proteins within lesions is restricted to specific lesion zones or (2) the origin of such proteins is endogenous (i.e. as a remnant of the developmental process) or exogenous, originating in the saliva or gingival crevicular fluid. The present study used a combination of immunohistochemistry and microradiography to determine the distribution of two proteins, serum albumin and salivary amylase, within natural white–spot carious lesions in relation to specific levels of demineralisation. The results indicated that albumin is found primarily in a region of between 10 and 20% demineralisation (an area of transition between the ‘dark’ zone and lesion ‘body’), with smaller quantities occurring in the region between 0 and 10% demineralisation and trace amounts in the zone indistinguishable from sound enamel by microradiography. A similar distribution was found for amylase in that the heaviest labelling was within the 10–20% demineralisation zone, although little if any was present in the 0–10% zone. The presence of these molecules in a region of the lesion where some potential for reprecipitation may exist will have important implications with respect to lesion progression.
In vitro Fluoride Dose–Response Study of Sterilized Enamel Lesions
Authors: Toro M.J. , Lukantsova L.L. , Williamson M. , Hinesley R. , Eckert G.J. , Dunipace A.J.
Published: April 2003

Currently our intra–oral model uses enamel specimens that have been disinfected by soaking in buffered formalin (pH 6.8). However, because of increasing emphasis on infection control, it is important to identify a way to sterilize these specimens. The aim of this study was to determine if autoclaved, or gas sterilized, lesioned enamel responds to fluoride (F) in the same way alcohol–disinfected enamel lesions do. Seventy–two formalin–disinfected, human enamel specimens (3 mm) were lesioned in demineralizing solution for 96 h and were then divided into three groups. One group was autoclaved; one group was gas sterilized (ethylene oxide), and the remaining 24 specimens were further disinfected in 70% ethanol for 10 min. Specimens in each group were then treated 4 times/day for 4 weeks with 0, 250 or 1,100 ppm F dentifrice slurries in an in vitro cycling, remin/demin model. Following treatment, fluoride uptake was analyzed by microdrill biopsy, and lesion depth and mineral content changes (ΔM) were determined by transverse microradiography. Data were analyzed by one–way ANOVA analysis. In all three groups of specimens there were significant (p<0.05) differences in fluoride uptake in response to different fluoride treatments. Autoclaved lesions failed to provide dose– response data with regard to changes in lesion mineral content. Because formalin and 70% alcohol are only disinfectants, and autoclaving altered the responsiveness of enamel lesions, results from this study suggest that, of the methods tested, gas sterilization is the preferred method for sterilizing enamel specimens that will be used in intra–oral studies.
Mast Cells Accumulate in Rat Bone Marrow after Ovariectomy
Authors: Lesclous Ph. , Saffar J.L.
Published: April 2003

We have previously shown that mast cells (MC) may act as accessory cells of bone resorption in a synchronized model of resorption. The aim of this study was to verify whether bone marrow MC accumulated during the phase of rapid osteopenia development in estrogen-deprived rats. Sprague-Dawley rats, 90 days old, were subjected to bilateral ovariectomy (OVX) or sham surgery (controls). Bone histomorphometry was performed in the proximal tibia metaphysis. Thirty days after surgery, serum estradiol had dropped (p < 0.002), and osteopenia was well established in the OVX rats (trabecular bone volume decreased by 69%, p < 0.0001). The indices of bone resorption were strongly modified: the number (p < 0.0001) and individual activity (p < 0.001) of the trabecular osteoclasts were prominently increased in the OVX rats. Ovariectomy resulted in a dramatic increase in the number of bone marrow MC (p < 0.0001), 97% of which were of the mucosal subtype. These results show that MC accumulate concomitantly with osteoclast generation in estrogen-deficient rats. Although the biological significance of this MC increase is unknown from these results, we hypothesize that MC might play a role in ovariectomy-induced bone loss similar to that they we previously proposed in a mechanically activated model of resorption.
Histological Effects of Vitamin A on the Tail-Amputated Tadpoles of Polypedates maculatus with Special Reference to Homeotic Transformation
Authors: Das P. , Mohanty-Hejmadi P.
Published: April 2003

Vitamin A is a very common teratogen causing severe embryonic malformations and changes in pattern formation in amphibians. The effects of vitamin A include the induction of duplication of skeletal structures in the anteroposterior, proximodistal and dorsoventral axes. The purpose of this investigation was to study the histological changes in the regenerating tail of the tadpoles of Polypedates maculatus by treatment with vitamin A. The histological changes brought about by vitamin A included the development of multilayered epidermis and thickened basement membrane, enlargement of the notochord and the nerve cord and the clumping of muscles. In addition, single, paired and supernumerary homeotic limbs were visible from day 20 onwards at ectopic sites. Initially, the limb consisted of only procartilage cells. Muscles and digits appeared from day 48 onwards. In contrast, such observations were not found in the control tails. The significance of such changes is discussed.
Effects of Maternal Alcohol Consumption on the Allometric Growth of Muscles in Fetal and Neonatal Rats
Authors: Nwaogu I.C. , Ihemelandu E.C.
Published: April 2003

The effect of maternal alcohol consumption during pregnancy as well as the neonatal period on allometric growth of skeletal muscles of fore and himdlimbs was studied in 252 rats (126 males and 126 females). At the inception of the study the dams of alcohol-exposed groups received 10% ethanol (v/v) in water for 2 weeks and 20% ethanol (v/v) for another 3 weeks. They were then bred overnight by introducing 1 male per 4 females into the cage. Following diagnosis of pregnancy, the two alcohol-exposed groups received 30% ethanol (v/v) till delivery. Neonatally the pre- and postnatal alcohol-exposed group continued to receive alcohol till weaning at 21 days of age. The offspring randomly selected (7 males and 7 females) from each group were killed at 3, 5, 7, 9, 11 and 14 weeks of age. The body weights, muscle weights and percentage of body weights contributed by each muscle were significantly smaller in the offspring of the alcohol-exposed groups as compared to the controls. These parameters were significantly higher in the group exposed to alcohol only prenatally as compared to those exposed both pre- and postnatally up to the 7th week of age, and thereafter were similar in the subsequent weeks. Although the alcohol-exposed groups grew faster than the controls from 9 to 14 weeks of age, they were, however, not able to catch up. This demonstrated that allometric growth of muscles of fetal and neonatal rats was adversely affected by maternal consumption of alcohol during pregnancy and neonatally.
Morphology of the Drifting Osteon
Authors: Robling Alexander G. , Stout Sam D.
Published: April 2003

Drifting osteons were followed longitudinally through the cortex of human and baboon long bones using serial sections. Direction of transverse drift was recorded at different cross-sectional levels of the same systems, and maximum angular change in drift direction was measured for each system. Most drifting osteons exhibit: (1) substantial (∼90°) variation in the direction of transverse drift along their longitudinal axes, (2) intermittent regions of concentric (type I) morphology, and (3) change in drift direction over time, evident at single cross-sectional levels. Additionally, 3-dimensional reconstruction reveals that the basic multicellular units (BMUs) responsible for creating drifting osteons are morphologically distinct from the cutting-cone–closing-cone model BMUs that produce other types of osteons. The stimulus involved in the activation and guidance of drifting BMUs is unclear, but it is likely that the complex strain environment experienced by long bone cortices exerts a significant influence on their morphology.
Variations in Cell and Structure Populations along the Length of Murine Small Intestine
Authors: Brennan P.C. , McCullough J.S. , Carr K.E.
Published: April 2003

Previous workers have reported a range of structural variations occurring along the length of small intestine. These studies have concentrated on the major intestinal components with little information available on the intersite variation of other members of a highly heterogeneous population. Using resin histology, the current study has collected data per circumference for all definable structural features within the murine intestinal wall, along with measurements for epithelial, muscle, nerve and connective tissue areas, and villous height and cryptal depth. Seven different sites along the length of the small intestine were examined. Following statistical comparisons a number of features exhibited no intersite variation; these were numbers of villi, submucosal vessels, myenteric nerve plexus profiles, inner muscle nuclei and apoptotic bodies as well as measurements for tissue areas and cryptal depth. Variations were seen between sites for crypts, enterocytes, villous and cryptal stromal cells, cryptal goblet cells, cryptal non-secretory epithelial cells, Paneth cells, endocrine cells, intra-epithelial lymphocytes, submucosal nerve plexus profiles, outer muscle nuclei and mitotic figures. A reduced villous height was observed caudally. Certain correlations between villous height/crypt number and constituent parameters have been noted. The results provide a complete description of how each definable structural feature within the gut wall varies at regular intervals along the length of the small intestine in C57 BL mice. A number of previously unreported variations have been described. The work provides a comprehensive data bank for future intestinal investigations.
Connexin43 Expression in Network-Forming Cells at the Submucosal-Muscular Border of Guinea Pig and Dog Colon
Authors: Nakamura Kei-ichiro , Shibata Yosaburo
Published: April 2003

The tissue-specific expression of connexin subtypes in gap junctions between the interstitial cells and smooth muscle cells in the submuscular plexus of the colon has a functional importance in relation to intestinal pacemaker activity. Immunocytochemical observations of two types of connexin molecules, connexin43 and connexin45, were made with a confocal laser scanning microscope on cryosections of freshly frozen dog, guinea pig, mouse and rat proximal colon. Connexin43 immunoreactivity appeared as a series of dots along the submuscular plexus of guinea pig and dog. In contrast, connexin43 immunoreactivity was not found in mouse and rat colon. Connexin43 immunoreactivity was not observed in the colon muscular layer in the four animal species examined. In double-stained materials with a marker for either vimentin or smooth muscle actin, connexin43 immunoreactivity was colocalized with vimentin immunoreactivity, whereas it was not with either smooth muscle actin immunoreactivity or phalloidin reactivity. This indicated that the connexin43-expressing cells possess a vimentin-positive fibroblast-like nature rather than a smooth muscle-like one. In addition, in guinea pig colon, connexin43 immunoreactivity colocalized with c-Kit immunoreactivity. In conclusion, network-forming cells are connected by connexin43 gap junctions in the submuscular plexus of guinea pig and dog colon, most likely indicating that interstitial cells act as an intestinal pacemaker and conductive system.
Innervation of Human Trigeminal Nerve Blood Vessels
Authors: Smoliar E. , Smoliar A. , Belkin V.Sh.
Published: April 2003

Film preparations and histological sections of human trigeminal nerve impregnated with silver nitrate and treated according to Falck-Hillarp revealed a rich innervation within the intraneural blood vessels. Highly diverse and complex neural interconnections were noted in the arterioles and venules of the trigeminal ganglion capsule as well as in the epineurium and external layers of the perineurium of the trigeminal nerve branches. Neural plexuses were detected on the vessel walls within these layers. Sensory innervation of the neural blood vessels was mainly relegated to polyvalent tissue-vascular receptors with adrenergic neural plexuses encountered on the walls of the intraneural vessels.
Sympathetic and Sensory Innervations Are Heterogeneously Distributed in Relation to the Blood Vessels at the Extensor carpi radialis brevis Muscle Origin of Man
Authors: Ljung Björn-Ove , Forsgren Sture , Fridén Jan
Published: April 2003

By using immunohistochemistry and antibodies to a general nerve marker, protein gene product (PGP) 9.5, the overall innervation at the extensor carpi radialis brevis (ECRB) muscle origin was investigated in patients with tennis elbow and in healthy controls. The autonomic innervation was studied by using antibodies to neuropeptide Y (NPY), tyrosine hydroxylase (TH), and vasoactive intestinal peptide (VIP). The sensory innervation was visualized by using antibodies to substance P and calcitonin gene-related peptide. PGP 9.5 immunoreactions were detected in association with small blood vessels and arteries and within nerve bundles. There was, however, heterogeneity in the perivascular nerve fiber distribution since some blood vessels exhibited a high degree of PGP 9.5 innervation and some negligible or no such innervation at all. There was marked TH/NPY innervation in the walls of a subpopulation of the arteries, basically no VIP-containing nerves, and sensory innervation restricted to the small blood vessels. These observations show that the ECRB muscle origin is supplied with heterogeneously distributed sympathetic and sensory innervations and, furthermore, that there appears to be an imbalance between the vasoconstrictor and vasodilator innervations along the vascular tree in this region.
Correlation between Surface Electromyography and Kinematics of the Hindlimb of Horses at Trot on a Treadmill
Authors: Robert C. , Valette J.P. , Degueurce C. , Denoix J.M.
Published: April 2003

The purpose of this study was to demonstrate the feasibility of surface electromyography in the horse and to correlate electromyographic activity with kinematic data. Surface electromyography of seven hindlimb muscles was recorded in five horses at trot on a treadmill. Simultaneously, kinematic analysis of the hindlimb was performed using a three-dimensional system and a unidirectional accelerometer was attached to the hoof. Electromyographic activities of the gluteus medius, vastus lateralis and two parts of the biceps femoris started in the late part of the swing phase and ended in the late period of the stance phase or the early period of the next swing phase. The semitendinosus showed two bursts of activity. The tensor fasciae latae acted when the previous muscles were inactive. Activity of the extensor digitorum longus was of low level but lasted during most of the step cycle. Correlation between electromyography, kinematics and anatomy helps us to understand the complex role of biarticular muscles: the tensor fasciae latae flexes the hip joint during the swing phase and extends the stifle joint during the stance phase, whereas the semitendinosus extends the hip joint during the stance phase and flexes the stifle joint during the swing phase. Cranial and caudal regions of the biceps femoris were also found to be bifunctional. Surface electromyography correlated with kinematic analysis gives valuable information about the functions and the timing of activity of the hindlimb muscles.
Chicken Embryonic Stem Cells and Transgenic Strategies
Authors: Pain B. , Chenevier P. , Samarut J.
Published: April 2003

The production of transgenic birds is an important goal for both fundamental and applied biology. Different methods have been employed to generate transgenic chickens, including microinjection, use of retroviruses and transfection of primordial germ or embryonic germ cells. In this review we will briefly describe these techniques and our efforts to obtain genetically modified avian embryonic stem (ES) cells using liposomes. This latter technique should allow us to modify chicken ES cells with a high efficiency, permitting the rapid generation of transgenic bird lines.
Structural Dynamics and Function of Early Embryonic Coats
Authors: Denker H.-W.
Published: April 2003

The extracellular embryonic coats (embryo/blastocyst coverings) that surround early mammalian embryos are most often still referred to as zona pellucida. Accumulating evidence from a number of earlier and recent studies clearly indicates that this is an oversimplification which cannot be defended anymore, at least in many species. Structural modifications of the coats occur during cleavage and blastocyst stages; these are most obvious in a number of species with the central type of implantation and, related to this, a high degree of blastocyst expansion, notably the rabbit and the horse. In this contribution, formation and transformation of the various layers of coats (zona pellucida, mucoprotein layer, neozona and gloiolemma in the rabbit, capsule in the horse) will be reviewed, as will be comparable structures seen, e.g., in the fur seal (subzonal layer) and the baboon. These phenomena will be discussed in the context of structurally more subtle changes found in other species, including those with small blastocysts and other types of implantation, in particular with biochemical modifications which may be physiologically quite important. The molecular mechanisms of deposition of coats and their transformation and shedding/dissolution will be briefly addressed. The possible functional significance of the coats and their transformation will be discussed (mechanical, morphogenetic and immunological role, molecular transport control, blastocyst positioning, implantation, trap and reservoir function for signalling molecules).
Oophorectomy-Induced Osteopenia in Rats in Relation to Age and Time Postoophorectomy
Authors: Patlas N. , Zadik Y. , Yaffe P. , Schwartz Z. , Ornoy A.
Published: April 2003

Oophorectomized (OVX) rats served for many years as a popular model for ‘postmenopausal’ osteoporosis in spite of the fact that the rat continues to grow during these experiments. We performed OVX in rats at 1, 3, 6 and 10 months of age and compared the histomorphometric (bone size, bone trabecular and cartilage volume in different areas) and chemical (ash, Ca, P and Mg content) parameters at 2, 6, 8 and 20 weeks post-OVX (2–20 weeks) to those of sham-operated rats. Significant differences were observed only in the animals that were OVX at a young or young-mature age, i.e. mainly at 1 and 3 months and some of the rats at 6 months of age. There were no changes in bone ash and mineral contents in the OVX animals in comparison to sham-operated rats, except 2 weeks post-OVX in the 1-month-old rats where these variables were reduced. The most significant finding was a reduction in the metaphyseal bone volume. This was observed in the rats OVX at 1, 3 and 6 months of age, but not in those OVX at 10 months. In the young OVX rats there was also an increase in epiphyseal cartilage volume. The epiphyseal and diaphyseal bone volumes were not different between the groups at any time postsurgery, explaining the lack of differences in bone ash and mineral contents. There were no significant changes in the results of the histomorphometric studies between OVX and sham-operated rats when surgery was performed at 10 months of age. Since OVX exerts significant changes only in young rapidly growing rats, this approach is an inappropriate model for postmenopausal osteoporosis, which occurs long after bone growth has ended.
Shape, Orientation and Spacing of the Primary Epidermal Laminae in the Hooves of Neonatal and Adult Horses (Equus caballus)
Authors: Douglas Janet E. , Thomason Jeffrey J.
Published: April 2003

Circumferential and proximodistal variations in the morphology of the primary epidermal laminae of six neonatal and five adult equine feet were documented. Three parameters were quantified: interlaminar spacing, the orientation of the laminae with respect to the overlying wall, and any angulation within the laminae themselves (‘internal angle’). In adult feet, the laminae were most closely spaced at the dorsum, the spacing increasing gradually towards the heels. In foals there was a non-significant trend for the dorsal laminae to be more widely spaced than those in more caudal parts of the foot. In both age groups, the dorsal laminae were almost straight (mean divergence from linearity at all sites 2°), and were oriented at approximately 90° to the tangent to the overlying wall (mean orientation for all sites 91°). At the quarters, the laminae were in general oriented caudally relative to the tangential position from their epidermal to their dermal ends (mean orientation of >90° at 12 of 16 sampling sites, where an orientation of >90° defines a ‘caudally directed’ orientation) and, in general, had a bend within their length (mean absolute value of internal angle for all sites 9°). At the heels there was greater variability in the data for both laminar orientation and internal angle. Overall, the foal feet showed greater mediolateral symmetry and less proximodistal variation than did the adult feet. In both age groups, rapid spatial changes in laminar morphology were closely associated with the position of the margins of the third phalanx.