bluuebunny/crossref_metadata_2025 huggingface dataset:
Frequency and distribution of endodontically treated teeth and apical periodontitis in an urban Danish population
Authors: Kirkevang L‐L. , Hörsted‐Bindslev P. , Ørstavik D. , Wenzel A.
Published: March 2003

Aim The aim of this study was to investigate the prevalence of endodontically treated teeth and apical periodontitis (AP) in a Danish population.

Methodology From Aarhus County 614 individuals were radiographically examined, and the frequency of endodontic treatment and periapical status of all teeth were assessed. The year of birth of the subjects ranged from 1935 to 1975. The chi‐squared test was used to determine the significance of differences between males and females and amongst age and tooth groups for the following parameters: AP, the number of endodontically treated teeth, and the number of endodontically treated teeth with AP.

Results A total of 15 984 teeth were examined; of these 538 (3.4%) had AP and 773 (4.8%) had been endodontically treated. Of the endodontically treated teeth, 404 (52.2%) had AP. Females had more endodontically treated teeth than males; otherwise, no effect of gender was observed. Significantly more molars (P < 0.01) had been endodontically treated (8.1%) compared to premolars (5.4%) and anterior teeth (2.5%). The prevalence of AP in connection with molars was significantly (P < 0.01) higher (7.0%) than premolars (2.8%) and anterior teeth (1.5%). The prevalence of endodontically treated teeth and of teeth with AP gradually increased with age.

Conclusions  The average number of teeth, the number of teeth with AP and the number of teeth with endodontic treatment in Danish adults were comparable to findings in other European countries. The frequency of endodontically treated teeth with AP was found to be high compared to that demonstrated in other epidemiological studies.
Aetiology of root canal treatment failure: why well‐treated teeth can fail
Authors: Siqueira J. F.
Published: March 2003

Literature review

Root canal treatment usually fails when the treatment is carried out inadequately. However, there are some cases in which the treatment has followed the highest standards yet still results in failure. In most of the cases, the endodontic failure results from persistent or secondary intraradicular infection. Extraradicular infections may also be implicated in the failure of some cases. In addition, it has been claimed that a few cases can fail because of intrinsic or extrinsic nonmicrobial factors. The purpose of this paper is to discuss the aetiology of the failure of root canal treatment, particularly in cases of well‐treated root canals. Indications for the treatment of endodontic failures are also discussed.
Root and canal morphology of Burmese mandibular molars
Authors: Gulabivala K. , Aung T. H. , Alavi A. , Ng Y‐L.
Published: March 2003

Aim

To study the root canal morphology of Burmese mandibular molars using a canal staining and tooth clearing technique.

Methodology

Mandibular molars (331) were collected from indigenous Burmese patients and designated; first (139), second (134), third (58) molars. Following pulp tissue removal and staining of the canal systems with Indian ink, the teeth were decalcified and rendered clear with methyl salicylate. Under magnification (×3), the following features were evaluated: (i) root number and morphology, (ii) number of canals per root, (iii) root canal configuration (Vertucci’s classification), (iv) number of apical foramina per root, (v) number and location of lateral canals and (vi) the presence of intercanal communications.

Results

Most of the mandibular molars had two separate roots (90% in first molars, 58% in second molars, 53% in third molars) and three‐rooted teeth were (10%) confined to first molars. C‐shaped roots occurred in 22.4% of mandibular second molars and a further 14.9% had two fused roots. The majority (81–100%) of conical distal roots possessed a simple type I (single canal) configuration. Whilst the canal system of mesial roots was more complex; 52–85% contained two canals, of which type II (two orifices, one foramen) and type IV (two separate canals) were the most prevalent. A broad range of 6.5–70% had intercanal communications. Fused/single‐rooted molars had a wide variety of canal system types but intercanal communications were rare except in C‐shaped roots (33%) of second molars. The majority of roots of all molars contained one or two apical foramina (91–96%) and the apical third had the highest prevalence of lateral canals.

Conclusions

There was a high prevalence of three‐rooted mandibular first molars and C‐shaped roots/canals in mandibular second molars from a Burmese population. Conical roots tend to have simple canal systems, whilst flatter/broader roots have more complex canal systems.
Enterococcus faecalis– a mechanism for its role in endodontic failure
Authors: Love R. M.
Published: March 2003

Aim

The aim of this study was to identify a possible mechanism that would explain how E. faecalis could survive and grow within dentinal tubules and reinfect an obturated root canal.

Methodology

Cells of Streptococcus gordonii DL1, Streptococcus mutans NG8, or E. faecalis JH2–2 were grown in brain heart infusion broth containing various amounts of human serum for 56 days. The ability of the three species to invade dentine and bind to immobilized type 1 collagen in the presence of human serum was assessed by dentine invasion and microtitre well experiments.

Results

All three species remained viable over the period of the experiment when grown in human serum. Cells of all three bacteria were able to invade dentine and bind to immobilized collagen. Both of these properties were inhibited by the presence of collagen in the cell solution. Human serum inhibited dentine invasion and collagen adhesion by S. gordonii DL1 and S. mutans NG8, whilst dentine invasion by E. faecalis JH2–2 was reduced in the presence of serum, but not inhibited, and binding to collagen was enhanced.

Conclusions

It is postulated that a virulence factor of E. faecalis in failed endodontically treated teeth may be related to the ability of E. faecalis cells to maintain the capability to invade dentinal tubules and adhere to collagen in the presence of human serum.
A new technique for the study of periapical bone lesions: ultrasound real time imaging
Authors: Cotti E. , Campisi G. , Garau V. , Puddu G.
Published: March 2003

Aim This study describes the use of a real time‐ultrasound imaging technique (echography) for the study of periradicular lesions.

Methodology Twelve patients with periapical lesions of endodontic origin, diagnosed with conventional clinical and radiographic examination, were examined further using echography at the site of the diagnosed lesions. Each lesion was echographically characterized and described by an expert echographist together with an endodontist. Once the major echographic features were identified, information on the size of the lesion, its content, and its vascular supply was obtained and recorded. A tentative differential diagnosis between a cyst and a granuloma was made based on the data.

Results In all cases it was possible to obtain an echographic image. It was also possible to measure the lesions, to evaluate their content and to view their vascularization in different regions of the mouth.

Conclusions Ultrasound real time imaging is a promising diagnostic technique in endodontology, but further work is required to refine the process.
The ferrule effect: a literature review
Authors: Stankiewicz N. R. , Wilson P. R.
Published: March 2003

Literature review A ferrule is a metal ring or cap used to strengthen the end of a stick or tube. It has been proposed that the use of a ferrule as part of the core or artificial crown may be of benefit in reinforcing root‐filled teeth. A review of the literature investigating this effect is presented. The literature demonstrates that a ferrule effect occurs owing to the artificial crown bracing against the dentine extending coronal to the crown margin. Overall, it can be concluded that a ferrule is desirable, but should not be provided at the expense of the remaining tooth/root structure.
Gossypol: reasons for its failure to be accepted as a safe, reversible male antifertility drug
Authors: WAITES  , WANG  , GRIFFIN
Published: March 2003

Following clinical trials conducted in China in the 1970s, gossypol was proposed as a drug for male contraceptive use. This review summarizes the extensive investigations on formal animal toxicology and on the recovery of fertility in men after stopping gossypol treatment which led to the decision by the Special Programme of Research, Development and Research Training in Human Reproduction (HRP) at the World Health Organization (WHO), that gossypol would not be acceptable as an antifertility drug. It is concluded that the assessment of gossypol reinforces the mandatory requirement that future contraceptive drugs must be developed by the established routes of appropriate animal toxicology and phased clinical studies.
Prognostic value of male diagnostic profiles in intracytoplasmic sperm injection (ICSI)
Authors: KOPPERS B. , GASSNER P. , MESCHEDE D. , HORST J. , BEHRE H. M. , NIESCHLAG E.
Published: March 2003

Possible correlations between male hormone and semen parameters with pregnancy and oocyte fertilization rates following intracytoplasmic sperm injection (ICSI) were investigated. The study is based on 290 couples who underwent ICSI therapy for the first time. The parameters evaluated were male age, serum levels of follicle stimulating hormone (FSH) and testosterone, sperm concentration, sperm motility, normal sperm morphology, index of teratozoospermia (TZI) and sperm vitality. A marginal, barely significant association was found between the fertilization rate and serum FSH levels in the male partner ( p = 0.046). There was no relevant association between male parameters and pregnancy rates. The study confirms that male hormonal and semen parameters are of low prognostic value for the outcome of ICSI.
Effects of sauna on sperm movement characteristics of normal men measured by computer‐assisted sperm analysis
Authors: SAIKHUN  , KITIYANANT  , VANADURONGWAN  , PAVASUTHIPAISIT
Published: March 2003

The effects of sauna exposure on sperm movement characteristics and other semen parameters were evaluated using computer‐assisted sperm analysis (CASA). A significant (p < 0.01) decrease in average path velocity (VAP), curvilinear velocity (VCL) and amplitude of lateral head displacement (ALH) was found after exposure to sauna for 2 weeks. The altered parameters returned to their original values within 1 week after cessation of sauna exposure. Mean values for semen volume, sperm count, percentage motility, sperm morphology and sperm penetration assay (SPA) were not statistically different during and after sauna, when compared to the corresponding control values. The results suggest that increasing scrotal temperature by sauna causes a reversible decrease in sperm movement parameters.
Extra‐epididymal spermatozoa express nuclear abnormalities
Authors: Potts  , Notarianni  , Jefferies
Published: March 2003

Extra‐epididymal spermatozoa account for approximately a third of all spermatozoa found in the normal human ejaculate. Whilst remaining outside of the testes at core body temperature, the functional competence of spermatozoa, including cell motility and fertilizing capacity, diminishes. By examining spermatozoa found in the seminal fluid of recently vasectomized men, this study has investigated the nuclear changes that occur in spermatozoa whilst persisting in sites distal to the epididymis. Spectral recordings of spermatozoa stained with the nucleic acid dye, toluidine blue and the sperm chromatin structure assay (SCSA) were performed. Toluidine blue staining of human sperm DNA is an effective predictor of abnormal protamine disulphide crosslinking and chromatin condensation. Using flow cytometry, the SCSA determines the sensitivity of sperm DNA to acid‐induced denaturation, providing a measure of chromatin and DNA damage. Abnormal protamine disulphide crosslinking and chromatin condensation was significantly higher in spermatozoa from patients after vasectomy when compared to normozoospermic controls (p < 0.01). Additionally, spermatozoa from vasectomized donors were significantly more sensitive to acid‐induced denaturation than were normozoospermic donors (p < 0.05). The results indicate that spermatozoa surviving in extra‐epididymal sites are more likely to possess DNA and chromatin abnormalities than those present in the testes and epididymis. These changes may partly explain the depletion of cell viability and fertilizing capacity of extra‐epididymal spermatozoa which has been reported previously.
Correlation between the motility of frozen–thawed epididymal spermatozoa and the outcome of intracytoplasmic sperm injection
Authors: Shibahara  , Hamada  , Hasegawa  , Toji  , Shigeta  , Yoshimoto  , Shima  , Koyama
Published: March 2003

The purpose of this study was to investigate if the outcome of ICSI was influenced by epididymal sperm motility in frozen–thawed specimens. A total of 18 ICSI treatment cycles using spermatozoa retrieved by microsurgical epididymal sperm aspiration (MESA) were analysed retrospectively. Cryopreservation of epididymal spermatozoa was performed when enough epididymal aspirates were collected. Sixty‐nine out of 126 oocytes injected with spermatozoa retrieved by MESA were fertilized, giving a fertilization rate of 54.8%. Out of 18 embryo transfer cycles, 6 (33.3%) achieved pregnancies. Fresh epididymal spermatozoa were used in 5 cycles while frozen–thawed epididymal spermatozoa were used in 13 cycles for ICSI. The fertilization rates were 68.6% (35/51) in the former group and 45.3% (34/75) in the latter group, respectively. There was a significant difference between the two groups (p < 0.05). In ICSI treatments using fresh epididymal spermatozoa, the cells used for injection were all motile. However, motile epididymal spermatozoa could be used in only five ICSI treatment cycles after freeze–thawing. In 6 cycles, only immotile sperm were used for injection of frozen–thawed spermatozoa. The fertilization rate in each group was 68.4% (13/19) and 31.6% (12/38), respectively. There was a significant difference between these groups (p < 0.01). These results indicate that the outcome of ICSI was influenced by sperm motility in frozen–thawed epididymal specimens. When no sperm motility could be recovered after freeze–thawing even with chemical treatments, consideration should be given to retrieving fresh epididymal spermatozoa again to achieve a better fertilization rate in such patients.
Expression of the integrin subunits α5, α6 and β1 in the testes of the common marmoset
Authors: Husen  , Giebel  , Rune
Published: March 2003

Integrin subunits α5, α6 and β1 were localized in the testis of pre‐pubertal or adult non‐human primates (Callithrix jacchus) by immunofluorescence staining and in situ hybridization. In animals of all ages subunits α5 and β1 were localized in cells of the lamina propria of the seminiferous epithelium. In prepubertal animals, the integrin subunits α5, α6, as well as β1, were distributed all over the plasma membrane of Sertoli cells. In adult animals the integrin subunits were confined to those plasma membrane regions of Sertoli cells which are assigned to the basal compartment, including the basement membrane of the seminiferous tubules. Protein expression of integrin subunits α6 and β1 was most pronounced in tubular stages in which elongated spermatids were not yet present in the adluminal compartment of the epithelium, suggesting that these integrin subunits are particularly essential at certain developmental stages of spermatogenesis. Non‐radioactive in situ hybridization revealed that the mRNA for integrin subunits α5, α6 and β1 was expressed by Sertoli cells. In situ hybridization, together with immunofluorescence data, shows that these integrin subunits were exclusively synthesized in Sertoli cells. As to functional aspects, it is concluded that during primate spermatogenesis, Sertoli cell integrins may be involved in both cell matrix as well as cell–cell interactions, particularly during early spermatogenesis.
Phytochemicals and the breakthrough of traditional herbs in the management of sexual dysfunctions
Authors: Adimoelja Arif
Published: March 2003

Traditional herbs have been a revolutionary breakthrough in the management of erectile dysfunction and have become known world‐wide as an ‘instant’ treatment. The modern view of the management of erectile dysfunction subscribes to a single etiology, i.e. the mechanism of erection. A large number of pharmacological agents are orally consumed and vasoactive agents inserted intraurethrally or injected intrapenially to regain good erection.

Modern phytochemicals have developed from traditional herbs. Phytochemicals focus their mechanism of healing action to the root cause, i.e. the inability to control the proper function of the whole body system. Hence phytochemicals manage erectile dysfunction in the frame of sexual dysfunction as a whole entity.

Protodioscin is a phytochemical agent derived from Tribulus terrestris L plant, which has been clinically proven to improve sexual desire and enhance erection via the conversion of protodioscine to DHEA (De‐Hydro‐Epi‐Androsterone).

Preliminary observations suggest that Tribulus terrestris L grown on different soils does not consistently produce the active component Protodioscin.

Further photochemical studies of many other herbal plants are needed to explain the inconsistent results found with other herbal plants, such as in diversities of Ginseng, Eurycoma longifolia, Pimpinella pruacen, Muara puama, Ginkgo biloba, Yohimbe etc.
Algorithm for diagnosis and treatment of erectile dysfunction in the era of sildenafil citrate
Authors: Kim Young Chan
Published: March 2003

Since Viagra (sildenafil citrate) was released as a pharmaceutical agent for the treatment of erectile dysfunction, it has had a big impact on the work undertaken in our practice. I herewith present an algorithm for the diagnosis and treatment of erectile dysfunction in the era of sildenafil citrate.
Properties of sperm separated using Percoll and IxaPrep density gradients. A comparison made using CASA, longevity, morphology and the acrosome reaction
Authors: McCann Christine T. , Chantler Eric
Published: March 2003

Since the withdrawal of Percoll from use in human assisted reproduction techniques in 1996, alternative density gradients have been sought. IxaPrep is one candidate that has low toxicity and can separate spermatozoa. Fractions of spermatozoa from normozoospermic men, separated by Percoll and IxaPrep gradient centrifugation, were assessed for sperm recovery, motility, morphology and the ability to undergo the acrosome reaction. The Percoll fractions had a significantly higher sperm recovery, motile count, rapid motile count, VAP, VSL, and VCL than those obtained using IxaPrep, both immediately after separation and up to 24 h later. In contrast, ALH, level of abnormal sperm morphology and the ability to acrosome react were not statistically different in sperm fractions separated using either gradient forming material.
Quantification of telomerase activity, porphobilinogen deaminase and human telomerase reverse transcriptase mRNA in testicular tissue – new parameters for a molecular diagnostic classification of spermatogenesis disorders
Authors: Schrader M. , Müller M. , Schulze W. , Heicappell R. , Krause H. , Straub B. , Miller K.
Published: March 2003

The aim of the study was to evaluate the quantitative detection of human telomerase reverse transcriptase (hTERT) mRNA and telomerase activity as new molecular diagnostic parameters for a subclassification of spermatogenesis disorders. Telomerase activity was detected by a quantitative telomerase PCR ELISA, and hTERT mRNA expression was quantified by fluorescence real‐time RT–PCR in a LightCycler® in cryopreserved testicular tissue specimens. This was paralleled by a histological workup. The discriminant analysis showed that detection of normalized hTERT expression was able to correctly classify 89.0% of the investigated tissue specimens into the subgroups of full spermatogenesis, maturation arrest or Sertoli‐cell‐only syndrome. In contrast, discriminant analysis revealed an only 58% accuracy of telomerase activity for the investigated tissue specimens. This study shows that the quantification of hTERT expression in testicular tissue by real‐time fluorescence RT–PCR is well suited for correctly classifying spermatogenesis disorders and proved to be markedly superior to the determination of telomerase activity.
How work‐place conditions, environmental toxicants and lifestyle affect male reproductive function1
Authors: Bonde Jens Peter , Storgaard Lone
Published: March 2003

Major temporal and geographical shifts in male reproductive function is presently an issue worldwide. The hormonal disruption hypothesis has achieved considerable attention but epidemiological evidence in support of the theory is lacking. Several occupational hazards to male reproductive function are known but exposure prevalences are hardly sufficient to play a role for reduced sperm count in the general male population. Sedentary work may be an exception. Perhaps prolonged time in the sedentary position exhausts the testicular heat regulation. But so far studies addressing implications of the heat hypothesis in the general population are few. Neither change of sexual behaviour nor reduced period of sexual continence seems to be a likely explanation. Tobacco smoking and consumption of caffeine and alcoholic beverages in adulthood have a rather marginal impact on spermatogenesis and can hardly explain major shifts or regional differences in male reproductive health. However, prenatal effects following smoking during pregnancy might play a role because we have witnessed a smoking epidemic among fertile women in some countries during the second half of the twentieth century. Moreover, if genetic factors play more than a marginal role for testicular function and sperm count, pregnancy planning resulting in reduced family size during the past 100 years could possibly explain a decline in semen quality because the most fertile part of the population reproduce less while the subfertile probably continue to get a limited number of children.
The ‘oestrogen hypothesis’– where do we stand now?1
Authors: Sharpe Richard M.
Published: March 2003

The original ‘oestrogen hypothesis’ postulated that the apparent increase in human male reproductive developmental disorders (testis cancer, cryptorchidism, hypospadias, low sperm counts) might have occurred because of increased oestrogen exposure of the human foetus/neonate; five potential routes of exposure were considered. This review revisits this hypothesis in the light of the data to have emerged since 1993. It addresses whether there is a secular increasing trend in the listed disorders and highlights the limitations of available data and how these are being addressed. It considers whether new data has emerged to support the suggestion that increased oestrogen exposure could cause these abnormalities and reviews new data on potential routes via which such increased exposure could have occurred. Secular trends: The disorders listed above are now considered to represent a syndrome of disorders (testicular dysgenesis syndrome, TDS) with a common origin in foetal life. Testicular cancer has increased in incidence in Caucasian men worldwide and lifetime risk is 0.3–0.8%. Secular trends in cryptorchidism are unclear but it is by far the commonest (2–4% at birth) congenital abnormality in either sex. Secular trends for hypospadias are not robust, although most studies suggest a progressive increase; registry data probably under‐estimates incidence, but based on this data hypospadias is the second most common (0.3–0.7% at birth) congenital malformation. Retrospective analyses of sperm count data show a global downward trend but this is inconclusive – prospective studies using standardized methodology show significant differences between countries and very low sperm counts in the youngest cohort of men. For all disorders, other then testis cancer, standardized prospective studies are the best way forward and are in progress across Europe. Oestrogen effects: Evidence that foetal exposure to oestrogens can induce the above disorders has strengthened. New pathways via which such changes could be induced have been identified, including suppression of testosterone production by the foetal testis, suppression of androgen receptor expression and suppression of insulin‐like factor‐3 (InsL3) production by foetal Leydig cells. Other evidence suggests that the balance between androgen and oestrogen action may be important in induction of reproductive tract abnormalities. Oestrogen exposure: Although many new environmental oestrogens have been identified, their uniformly weak oestrogenicity excludes the possibility that they could induce the above disorders. However, emerging data implicates various environmental chemicals in being able to alter endogenous levels of androgens (certain phthalates) and oestrogens (polychlorinated biphenyls, polyhalogenated hydrocarbons), and the former have been shown to induce a similar collection of disorders to TDS. Other mechanisms via which increased fetal exposure to pregnancy oestrogens might occur (increasing trend in obesity, dietary changes) are also discussed.
Pharmacological reactivity of neoplastic and non‐neoplastic associated neovasculature to vasoconstrictors
Authors: Andrade  , Beraldo
Published: March 2003

Angiogenesis and the pharmacological responses of the tumour and non‐tumour associated neovasculature have been investigated. Cannulated sponge discs in mice were used to host the angiogenic stimulators, while 133Xe washout was employed to assess local blood flow. Enhancement of blood flow was detected in implants bearing B16 cells, 3T3 cells and angiotensin II (AII)‐treated at day 7. The responses of non‐neoplastic associated neovasculature at day 14 post sponge implantation to the vasoconstrictors used endothelin‐1 (Et‐1), AII, platelet activating factor (PAF) and 5‐hydroxytryptamine (5‐HT) were dose‐dependent. By contrast, the newly formed blood vessels induced by tumour cells were markedly insensitive to the vasoconstrictors agonists Et‐1 and AII, while fully responsive to PAF and 5‐HT. The vessels resulting from neoplastic stimulus exhibited altered pharmacological reactivity, suggesting that the characteristics of the neovasculature are dependent on the nature of the angiogenic stimuli.
Hepatocyte growth factor in transgenic mice
Authors: Shiota Goshi , Kawasaki Hironaka
Published: March 2003

In order to clarify the function of hepatocyte growth factor (HGF) in vivo, we have developed transgenic mice expressing HGF in the liver. The bromodeoxyuridine labelling indices in livers from HGF transgenic mice were doubled, compared to those from wild type mice. Livers of HGF transgenic mice expressed high levels of c‐myc, which was the consequence of increased transcription rates through the c‐myc promoter. After 70% partial hepatectomy, the livers of HGF transgenic mice recovered in half the time needed for their normal siblings. Since we found that HGF inhibits growth of hepatocellular carcinoma (HCC) cells in vitro, we have made two kinds of double transgenic mice: HGF/TGFα and HGF/c‐myc mice. The double transgenic mice expressing both HGF and TGFα had lower tumour yields, compared to TGFα transgenic mice. The HGF/c‐myc double transgenic mice had a lower incidence of hepatocellular adenoma (HCA) and HCC in comparison with c‐myc transgenic mice. In HGF/c‐myc mice, there were more apoptotic cells and less mitotic cells than c‐myc transgenic mice. These data indicate that HGF inhibits growth and occurrence of HCC in vivo. We also found that HGF protects liver from D‐galactosamine (D‐GalN)‐induced injury. Hepatic prostaglandin E 2 (PGE2) contents in HGF transgenic mice were much higher than those in wild type mice, and were associated with hepatic HGF contents. An anti‐HGF antibody inhibits production of PGE2 in liver after D‐GalN administration. These data suggest that HGF protects liver from D‐GalN‐induced injury through increased liver PGE2 production. The data obtained from HGF transgenic mice suggests the possibility that HGF could be applicable for therapy of human liver diseases in the future.
Muscle cells become necrotic rather than apoptotic during reperfusion of ischaemic skeletal muscle
Authors: Knight Kenneth R. , Messina Aurora , Hurley John V. , Zhang Baimeng , Morrison Wayne A. , Stewart Alastair G.
Published: March 2003

While necrosis is known as a major mechanism for the loss of viability of skeletal muscle following ischaemia and reperfusion, much less is known of the role of apoptosis. In this study rat hind limbs were subjected to 2 h of tourniquet ischaemia, then reperfused for either 0, 0.25, 0.5, 1, 3, 8, 16 or 24 h (n = 6 per group). Mean viability of muscle, assessed by tetrazolium dye reduction, after 2 h ischaemia and 24 h reperfusion was 17%. Histological examination revealed disrupted, necrotic muscle fibres from 30 min to 24 h reperfusion. Apoptotic nuclei were identified by haematoxylin staining and TUNEL, terminal deoxynucleotidyl transferase mediated dUTP nick end labelling. No TUNEL‐positive cells were observed at the end of the ischaemic period, but a small number of TUNEL‐positive endothelial and smooth muscle cells were found at 30 min reperfusion, with a progressive increase in their number up to 24 h reperfusion. Apoptotic neutrophils were detected after 8–24 h reperfusion. At no stage was apoptosis seen in the nuclei of skeletal muscle fibres. It appears that apoptosis plays no role in the death of muscle fibres after ischaemia‐reperfusion injury to skeletal muscle.
Experimental hypersensitivity pneumonitis: influence of Th2 bias
Authors: Schuyler Mark , Gott Katherine , Mapel Vesta , Cherne Amy , Nikula Kristen J.
Published: March 2003

Cultured murine CD4+ cells from Saccharopolyspora rectivirgula sensitized C3H/HeJ (Th1 bias) donors can adoptively transfer murine experimental hypersensitivity pneumonitis (EHP). We sensitized BALB/c mice (Th2 bias) with S. rectivirgula, obtained spleen and lung associated lymph node (LALN) cells, cultured the cells with specific antigen, and attempted adoptive transfer of EHP. We also treated both C3H/HeJ and BALB/c donor mice with IL4 and anti‐IFNγ before exposure to S. rectivirgula and then cultured cells from both spleen and LALN before attempted transfer of EHP. We found that cultured spleen and lung associated lymph node cells can adoptively transfer EHP in both C3H/HeJ and BALB/c mice as demonstrated by infiltration of the recipient lungs with CD4+ lymphocytes. Treatment of both mouse strains with IL4 and anti‐IFNγ did not change the ability of cultured cells to adoptively transfer EHP. We conclude that EHP induced by S. rectivirgula can occur in animals with either a Th1 or a Th2 bias and is not altered by treatment with IL4 and anti‐IFNγ. This suggests that attributes of the antigen and not genetic background or cytokine environment at the site of initial sensitization determines the results of exposure to S. rectivirgula.
Epithelial stem cell repertoire in the gut: clues to the origin of cell lineages, proliferative units and cancer
Authors: Wright Nicholas A.
Published: March 2003

Gastrointestinal stem cells are shown to be pluripotential and to give rise to all cell lineages in the epithelium. After damage, gut stem cells produce reparative cell lineages that produce a wide range of peptides with important actions on cell proliferation and migration, and promote regeneration and healing. Increase in stem cell number is considered to induce crypt fission, and lead to increases in the number of crypts, even in the adult; it is also the mode of spread of mutated clones in the colorectal mucosa. Stem cell repertoire is defined by both intrinsic programming of the stem cell itself, but signalling from the mesenchyme is also vitally important for defining both stem cell progeny and proliferation. Carcinogenesis in the colon occurs through sequential mutations, possibly occurring in a single cell. A case is made for this being the stem cell, but recent studies indicate that several stem cells may need to be so involved, since early lesions appear to be polyclonal in derivation.
Endocrine cells in the denervated intestine
Authors: Santos Gilda C. , Zucoloto Sérgio , Garcia Sérgio B.
Published: March 2003

This study deals with the effects of myenteric denervation of the proximal jejunum on endocrine cell population of the crypt‐villus unit, 5 months after treatment with benzalkonium chloride (BAC). Male Wistar albino rats weighing on average 100 g were allocated to two groups: the BAC group − the proximal jejunal serosa was treated with 2 m m BAC for 30 min, and the control group − treated with saline solution (0,9% NaCl). There was a significant reduction in neurone number in the jejunal myenteric plexus of the BAC group and the endocrine cell population (serotoninergic and argyrophilic cells) was significantly increased in this intestine segment. In conclusion, the present findings provide further evidence that the myenteric denervation induced by BAC may lead to the development of a local imbalance of the neurotransmitters, with a consequent induction of enteroendocrine cell (argyrophilic and serotoninergic cells) hyperplasia in the crypt and villus.
The effect of IFNγ on the hepatocyte: cell cycle and apoptosis
Authors: Tura Benjamin J. , Bunyan Kerry E. , Harrison David J.
Published: March 2003

The inflammatory cytokine interferon gamma (IFNγ) can cause cell cycle arrest and apoptosis in the hepatocyte. Primarily these processes are protective but in chronic liver disease oncogenic mutations may prosper. IFNγ signalling is discussed showing how p53 is induced to cause cell cycle arrest. While caspases are are known to be responsible for IFNγ induced apoptosis, how they are activated is unclear. Potential mechanisms are reviewed.
Bond strength and interfacial micromorphology of compomers in primary and permanent teeth
Authors: El‐Kalla Ibrahim H , García‐Godoy Franklin
Published: March 2003

Objectives. To (1) test and compare the shear bond strength of compomers (Compoglass, Dyract, Hytac) to primary and permanent dentin, (2) compare the values to those obtained with a resin‐modified glass ionomer (Vitremer), and (3) evaluate the material–dentin interfacial morphology.

Sample and methods. The facial and lingual surfaces of 32 primary and 32 permanent teeth were used. The manufacturers’ instructions were followed for the bonding procedures. After bonding, the teeth were thermocycled and sheared.

Results. ANOVA and Student‐Newman‐Keuls test revealed that the shear bond strength for Dyract was significantly higher than for the other restorative systems tested, both for primary (P<0·001) and permanent (P<0·01) teeth. Compoglass bond strength was significantly lower than Vitremer for the primary teeth dentin (P<0·01). The shear bond strength for Compoglass to permanent dentin was significantly lower than for all other restorative systems (P<0·001). There was a significantly higher shear bond strength for Compoglass (P<0·05) and Dyract (P<0·01) restorative systems for prim‐ary compared to permanent teeth. For all products tested, all samples revealed cohesive failures. The highest frequency of cohesive failure was reported with Compoglass in both primary and permanent teeth and for Hytac and Vitremer in permanent teeth. Micromorphologically, all restorative systems revealed good adaptation to the underlying dentin; however, there was no evidence of the formation of a hybrid layer or deep resin penetration inside the dentinal tubules. There was no difference in the interfacial morphological adaptation between the primary and permanent teeth.

Conclusions. The compomers tested had shear bond strength values between those of resin‐modified glass ionomers and resin composites.
Dental findings in three siblings with Morquio’s syndrome
Authors: Rølling I. , Clausen N. , Nyvad B. , Sindet‐Pedersen S.
Published: March 2003

Three siblings with Morquio’s syndrome are described. Cultured fibroblasts from the youngest sibling demonstrated a total absence of N‐acethylgalactosamine‐6‐sulphate‐sulphatase whereas β–galactocidase activity was normal, thus verifying the diagnosis of MPS‐IV A. Dental features such as pointed cusps, spade‐shaped incisors, thin enamel and pitted buccal surfaces were observed in all three children. Furthermore, in all three siblings the TMJ was affected with severe resorption of the head of the condyle.

Histological examination of exfoliated primary molars showed a band of increased porosity following the striae of Retzius in the outer part of the enamel. These developmental disturbances were occasionally associated with minor localized defects in the enamel surface.

The importance of close monitoring of dental development and regular dental care in order to prevent attrition of the teeth, loss of vertical face height and subsequent risk of TMJ dysfunction is emphasized.
Provision of Atraumatic Restorative Treatment (ART) restorations to Chinese pre‐school children – a 30‐month evaluation
Authors: Lo E.C.M. , Holmgren C.J.
Published: March 2003

Summary.
Objectives. The objectives of this study were: to provide restorations using the ART approach to pre‐school children in Southern China in a kindergarten environ‐ment, using a high‐strength glass‐ionomer restorative material; to assess the accept‐ability of this approach and to evaluate on a longitudinal basis the restorations placed.

Sample and methods. A total of 170 ART restorations were placed in 95 children, aged 5·1 ± 0·7 years, by seven final‐year dental students using standard ART procedures and hand instruments. The restorations were evaluated every six months thereafter by two calibrated independent examiners using explorers and mouth‐mirrors.

Results. 93% of the children reported that they did not feel pain during treatment and 86% were willing to receive ART restorations again. The cumulative 12‐ and 30‐month survival rates of Class I restorations were 91% and 79%, respectively. The corresponding figures for Class V restorations were 79% and 70%, while those for Class II restorations were 75% and 51%. The failure rates of Class III and IV restor‐ations were high with more than half of them scored as missing within the first year.

Conclusions. The ART approach was shown to be acceptable to Chinese pre‐school children for providing restorative dental care outside the traditional clinical setting. The success rates were high for Class I and V restorations in primary teeth, modest for Class II, and low for Class III and IV restorations.
Effectiveness of a caries preventive program in pregnant women and new mothers on their offspring
Authors: Gomez S.S. , Weber A.A.
Published: March 2003

Objective. The medical centre at Almirante Nef Naval Hospital, Vina del Mar, Chile, operates a mother and child preventive dental program (PDP) which includes women from their fourth month of pregnancy and mothers with their offspring. The aim was to evaluate the effectiveness of this prenatal and postnatal prevention program after the first four years.

Methods. The prevalence of early childhood caries of 180 1‐ to 3·5‐year‐old children enrolled in the PDP was compared with 180 non‐participating children. The control group was randomly selected from the rolls of the healthy child system of the Valparaiso‐San Antonio Health Service and was comparable by age, socio‐economic status and level of fluoride in the drinking water (1·0 p.p.m. F) with the PDP group. Clinical caries examinations were conducted by two calibrated examiners using the WHO visual criteria.

Results. In the PDP group, 97% of the children were caries free compared with the 77% in the control group. The dft (mean ± SD) of the PDP children was 0·11 ± 0·78 versus 0·66 ± 1·55 for the control children, a difference of 83·3%. The differences between the groups in caries‐free status and caries prevalence were both statistically significant (P < 0·05).

Conclusions. The preventive dental program was effective in inhibiting caries in pre‐school children, even in a population already receiving the benefits of community water fluoridation.
Celiac disease and mineralisation disturbances of permanent teeth
Authors: Rasmusson C.G. , Eriksson M.A.
Published: March 2003

In a study from Finland in 1986 it was shown that celiac disease was often associated with tooth enamel defects of permanent teeth. This study also showed a strong association between the time of gluten challenge in the diagnostic procedure and enamel defects. In the current study, dental examinations were carried out for a group of 40 children and adolescents suffering from celiac disease diagnosed according to the criteria of The European Society of Paediatric Gastroenterology and Nutrition (ESPGAN) at the Department of Paediatrics, Hospital of Uddevalla, Sweden. A control group made of 40 healthy children of the same age, sex and living area was examined in the same way. The results failed to show disturbances of the same type, degree of severity or frequency as was reported in Finland and no statistically significant differences concerning enamel defects were found between the patients with celiac disease and the controls.
Multifactorial analysis of the aetiology of craniomandibular dysfunction in children*
Authors: Vanderas A. P. , Papagiannoulis L.
Published: March 2003

Summary. Objectives. It is generally accepted that the aetiology of craniomandibular dysfunction (CMD) is multifactorial. Different types of malocclusion, oral parafunctions especially bruxism, trauma of the mandible or temporomandibular joint (TMJ) and emotional stress are known aetiologic factors. Research has been conducted into the relationship between each of these aetiologic factors and the signs and symptoms of CMD. However, such an approach does not control for the simultaneous effect of other factors responsible for the development of the dysfunction. The purpose of this study was to investigate the effect of each aetiologic factor on the signs and symptoms of CMD in children, controlling for the effect of all other known factors by means of a multifactorial analysis.

Methods. A sample of 314 children, aged 6–8 years, was examined clinically for signs of CMD and morphologic and functional malocclusion. Symptoms of CMD and oral parafunctions were recorded by the same investigator in an interview. Emotional stress was measured through urinary catecholamines including epinephrine, norepinephrine and dopamine, detected in a 24‐h urine sample, using high performance liquid chromatography. A questionnaire was distributed to the parents to collect information regarding socioeconomic factors and the history of dentofacial injuries. A logistic multiple regression was carried out to estimate the partial effect of each aetiologic factor. A 95% probability level was used.

Results. Posterior crossbite with lateral shift significantly affected the probability of child developing deviation of the mandible on opening. Similarly, posterior crossbite and epinephrine had a significant impact on TMJ tenderness, overjet had an effect on clicking, clenching and biting of objects had an effect on muscle tenderness, and lip/cheek biting influenced dysfunctional opening. Of the symptoms reported, pain on wide opening was affected significantly by lip/cheek biting.

Conclusion. On the basis of these results, it can be suggested that parafunctional and some structural and psychological factors may increase the probability of the child developing the signs and symptoms of CMD.
Fluoride intake in children living in a high‐fluoride area in Ethiopia – intake through beverages
Authors: Malde M. K. , Zerihun L. , Julshamn K. , Bjorvatn K.
Published: March 2003

Summary. Introduction. The present study was conducted in Wonji Shoa, a sugar estate in the Ethiopian Rift Valley. Drinking water in the area is provided either by the Awash River or by high‐fluoride ground water wells. Defluoridation plants have been installed, but are not in regular use, and fluorosis, dental as well as skeletal, is endemic. The aim of this study was to assess daily fluoride intake from drinking water and beverages in children from neighbouring villages with varying fluoride concentration in the drinking water.

Subjects and methods. Thirty families were selected from two of the plantation villages (A and K). The criterion for being included in the project was the presence in the household of at least one child, fully weaned and below the age of 5 years. For sampling of beverages, the duplicate portion technique was used. The fluoride concentration in the beverage samples was determined using standard methods, using a fluoride ion‐selective electrode.

Results. Ten of the selected households in Village A fetched water from the Awash River (1·8 mg F−/L) while five relied upon water from a local well (2·1 mg F−/L). All 15 households in Village K used water from a local well with fluoride concentration of 14·4 mg/L. The mean daily fluoride intake from drinking water and beverages during the four days, varied from 1·2 to 1·5 mg and 5·9 to 8·8 mg in Village A and K, respectively. Low variety in types of beverages consumed was reported both during the study period and through the questionnaire. Only local water was used for beverage preparation. Children who consumed milk had a reduced fluoride intake. Tea, which was part of the children's diet, was not found to be a main source of fluoride.

Conclusion. A2n effective defluoridation of the drinking water or a change of water source would seem to be the only options for avoidance of dental and possibly skeletal fluorosis.
The use of focus groups in a study of attitudes to student nurse assessment
Authors: Lankshear Annette J
Published: March 2003

This paper describes the use of focus groups in the first phase of a study to investigate the attitudes of teachers and clinical assessors to the assessment of student nurses It offers a description of the methodology, with an analysis of its strengths and weaknesses
Some considerations concerning practice and feedback in nursing education
Authors: Greenwood J
Published: March 2003

Dominant approaches to reflective practice and experiential learning in Australia and the United Kingdom seem to reflect a limited view of the functions of practice and feedback in human learning These functions will be described from a cognitive psychological perspective and the weaknesses of such approaches discussed It will be argued that Schonian reflective practice and some experiential learning techniques can reinforce rather than eliminate inappropriate action tendencies and that this, in turn, could consolidate nursing's theory–practice gap
Action research: a few details, a caution and something new
Authors: Greenwood J
Published: March 2003

Action research aims to generate and test action theories and thereby to develop and potentially emancipate practitioners The precise nature of such action theories and what their generation and validation can potentially develop in practitioners are described The possible costs of emancipatory action for nurses and a novel and potentially powerful strategy to minimize such costs are discussed
The role and self‐perceived training needs of nurses employed in general practice: observations from a national census of practice nurses in England and Wales
Authors: Atkin Karl , Hirst Michael , Lunt Neil , Parker Gillian
Published: March 2003

This paper outlines the results of a national census of practice nursesin England and Wales It not only shows that the numbers of practice nurses have increased dramatically in recent years but also demonstrates how theirrole has evolved Many practice nurses are now involved in health promotion, and home visiting, as well as advice and counselling The findings also indicate that many practice nurses express a need for training Continuing education for practice nurses is important in ensuring practice nurses are fullyqualified and trained for the tasks they undertake In addition, it also enables them to develop their role and work alongside other community health professionals