Effects of anterior cruciate ligament (ACL) injury on postural control and muscle activity of head, neck and trunk muscles

The aim of the study was to evaluate the effects that an anterior cruciate ligament injury of the knee has on postural control and activity of neck, head and trunk muscles to investigate the existence of connections between the masticatory system and body posture. Surface electromyographic activity of the muscles at mandibular rest position, and during maximal voluntary clenching and posturometric and stabilometric measurements of 25 adult patients having pathology on the left knee were compared with a control non-pathological group. At rest, the patients showed a higher muscular activity of anterior temporalis, masseter, sternocleidomastoid and lower trapezius, compared with the control subjects (P < 0.05). At maximal voluntary clenching, the patients showed a lower muscular activity of the right anterior temporalis and masseter and a higher muscular activity of the lower trapezius, compared with the control subjects. For the stabilometric measurements, all the subjects showed a significant reduction in the postural centre of pressure path length during the test with eyes open and cotton rolls, compared with the test with eyes closed and mandibular rest position (P < 0.05). In addition, the patients showed a significant displacement of the postural centre of pressure in a forward direction (P < 0.05) and into the right side (P < 0.05), compared with the control subjects. Anterior cruciate ligament injury appears to be associated to a change in the activity of head, neck and trunk muscles and to a change in the position of the postural centre of pressure. Cotton rolls seem to improve the stability of the subject.

Gene expression profiles underlying alternative caste phenotypes in a highly eusocial bee, Melipona quadrifasciata

To evaluate caste-biased gene expression in Melipona quadrifasciata, a stingless bee, we generated 1278 ESTs using Representational Difference Analysis. Most annotated sequences were similar to honey bee genes of unknown function. Only few queen-biased sequences had their putative function assigned by sequence comparison, contrasting with the worker-biased ESTs. The expression of six annotated genes connected to caste specificity was validated by real time PCR. Interestingly, queens that were developmentally induced by treatment with a juvenile hormone analogue displayed an expression profile clearly different from natural queens for this set of genes. In summary, this study represents an important first step in applying a comparative genomic approach to queen/worker polyphenism in the bee.

Influence of knee pathology on body posture and muscle activity of head, neck and trunk muscles

AIM

The aim of the study was to evaluate the effects that an anterior cruciate ligament (ACL) injury of the knee has on postural control and activity of neck, head and trunk muscles in order to investigate the existence of connections between the masticatory system and body posture.

METHODS

Surface electromyographic (sEMG) activity of the muscles and their asymmetry index, at mandibular rest position, and during maximal voluntary clenching (MVC), and posturometric and stabilometric measurements of 25 patients (mean age 28+/-9 years) having undergone ACL injury of the left knee were compared with a control non-pathologic group.

RESULTS

At rest, the patients showed a higher sEMG activity of the anterior temporalis, masseter, sternocleidomastoid and lower trapezius, compared with the control subjects (P<0.05). At MVC, the patients showed a lower sEMG activity of the right anterior temporalis and masseter and a higher sEMG activity of the lower trapezius, compared with the control subjects. For the stabilometric measurements, all the subjects showed a significant reduction in the Center of Pressure (CoP) path length during the test with eyes open and cotton rolls, compared with the test with eyes closed and mandibular rest position (P<0.05). In addition, the patients showed a significant displacement of the CoP in a forward direction (P<0.05) and to the righ side (P<0.05), compared with the control-subjects during each test.

CONCLUSIONS

ACL injury appears to be associated to a change in the sEMG activity of head, neck and trunk muscles and to a change in the position of the CoP of the body. Cotton rolls seem to improve the stability of the subject.

A multi-biomarker analysis of DNA damage in automobile painters

The genotoxic effects associated with automobile painting were analyzed using a panel of biomarkers. Chromosomal aberrations (CAs), sister chromatid exchange (SCE), and micronuclei were evaluated in 25 car painters (12 smokers, 13 nonsmokers) working in different automobile paint-shops in Italy and in 37 control subjects. The controls were healthy blood donors (14 smokers, 23 non-smokers) that were matched with the experimental population for gender and age. Air samples were analyzed regularly at the work places, and elevated concentrations of benzene and toluene were detected consistently. The exposed group had higher frequencies of CAs (both chromosome- and chromatid-type), micronuclei, and SCE (P < 0.5 - P < 0.001). Furthermore, exposed and control subjects were also genotyped for GSTM1 and GSTT1 polymorphism. No significant associations were detected between the biomarker responses and either the GSTM1 or GSTT1 genotype of the subjects, but the small sample size does not allow definite conclusions on the relationship between the genetic polymorphism and the biomarkers. The results indicate that automobile painters have increased levels of clastogenic and possible aneugenic damage and that smoking may be a confounding factor for the responses.

Immunohistochemical Evaluation of VEGF Inflamed Cystic Radicular Lesions and in Keratocysts

Vascular Endothelial Growth Factor, also known as Vascular Permeability Factor, is a multifunctional cytokine hyperexpressed during angiogenesis and in numerous physiological and pathological processes characterised by an increase of vascular permeability. The aim of this study was to evaluate the angiogenetic processes which are accompanied by an expansion of cystic radicular lesions and of keratocysts of the jaw bone. 12 subjects were chosen with an average age of 43 years, of whom 8 were males and 4 females. After an accurate history and physical examination, the patients underwent surgery for removal of the cysts. The samples taken were histologically and immunohistochemical examined. The histological exam confirmed the diagnosis of radicular cysts and keratocysts. The immunohistochemical examinations were positive for VEGF in all the lesions analysed, even though they had different immunostaining. Using a semi-quantitative method, in the radicular cyst samples it was possible to highlight a wider expression of the vascular component, both in the inflamed area and the adjacent stroma. The lesions with keratin content showed newly formed and modest vascularisation both in the area showing slight inflammation, where the cellular component was prevalent, and in the adjacent areas showing no inflammation. Therefore, angiogenesis could take on a primary role in the development of cystic lesions of the jaw. However, the differences of expression of the VEGF protein suggest the need for wider monitoring to better evaluate a possible use of such a protein as a diagnostic marker.

Surface electromyographic response of the neck muscles to maximal voluntary clenching of the teeth

The purpose of this study was to evaluate the activity of digastric, sternocleidomastoid, upper trapezius, lower trapezius and cervical muscles in response to maximum voluntary clenching (MVC) of the teeth. Twenty healthy subjects aged 24-31 years were divided into two groups of 10: a resting group and a clenching group. The resting group simply maintained the mandible at rest with teeth apart for two 1-min periods, whereas the clenching group underwent an initial resting period followed after 1-min by a clenching period during which they were required to perform MVC. The electromyography (EMG) responses of each muscle were recorded during all periods, and means and standard deviations of the root mean square EMG were calculated. Within-group and between-group comparisons of EMG activity were made using, respectively, the Sign two-tailed test for two related samples and the Kolmogorov-Smirnov two-tailed test for two independent samples (significance level 0.05). Data indicated a significant increase of EMG activity of the anterior neck muscles (digastric and sternocleidomastoid) during MVC as compared with EMG recorded during resting periods. If confirmed by further research, our findings suggesting an involvement of anterior neck muscles during isometric contraction of the jaw elevator muscles may have clinical implications.

[Opinions and attitudes of youngsters about sexually transmitted diseases]

A group of 1.085 students (582 M, 503 F) attending high school (742) and nursing school (343) filled in an anonymous questionnaire on their sexual habits and their knowledge of contraception and sexually transmitted diseases. Overall, 57% of the study population had already a complete sexual intercourse at a mean age of 16,4 (SD +/- 1,8). 74% had 1-3 sexual partners, whereas 28% had more than 3. All students affirmed that it was possible to prevent sexually transmitted diseases and 92,6% indicated correct methods. However 10% of students did not know that AIDS is transmitted sexually as 47% hepatitis B. The responses made by nursing students were more correct that those of high school students.

The Comet assay for the detection of DNA damage in Mus spretus from Doñana National Park

Doñana Park (Spain), a protected area in Europe, was affected by an environmental disaster in April 1998 that caused the spreading of acidic water and mud full of toxic metals from the Aznalcollar pyrite mine. In order to assess the contamination in the area and to monitor the possible biological effects of the toxic spill, a series of coordinated studies was performed utilizing several animal species living in that area. We performed genotoxicity monitoring using the Comet assay on peripheral blood leukocytes of the Algerian mouse (Mus spretus), a nonprotected rodent suitable as a bioindicator. The mice were sampled in different areas 6 months after the ecological disaster and again 1 year later. Our results showed that in 1998 all the areas examined were contaminated, as determined by an increase in the Comet assay parameters in the analyzed animals, whereas a significant decrease in the values of these parameters was observed in the 1999 samples, which were collected in a riverside area subject to tide flows. Thus, the Comet assay has proven to be an interesting and sensitive tool in studies of environmental genotoxicity.

Cerec 3 for orthodontics: a tool for treating deep bite

Bite-opening procedures are used in the early stages of orthodontic fixed treatment in order to: ease antero-posterior tooth movements; bracket the mandibular arch and level the Curve of Spee; prevent mandibular brackets from debonding; use regular straight archwires to proceed with treatment. For these purposes, removable or bonded biteplanes are universally recognized as very effective when the bite-opening is needed. Conventional orthodontic procedures include clinical solutions which effectively open the bite, but they all lack sufficient hygiene, comfort, and esthetics. The authors propose the use of the CAD-CAM technology with the Cerec 3 system (Sirona, Bensheim, Germany) to create an overcrown able to open the bite through clinical crown lengthening of the mandibular second premolars. The laboratory steps are described and the clinical efficacy is demonstrated with an orthodontic case report.

Strong antioxidant activity of ellagic acid in mammalian cells in vitro revealed by the comet assay

Oxidative stress due to oxygen and various radical species is associated with the induction of DNA single- and double-strand breaks and is considered to be a first step in several human degenerative diseases, cancer and ageing. Naturally occurring antioxidants are being extensively analysed for their ability to protect DNA against such injury. We studied three naturally occuring compounds, Ascorbic Acid, Melatonin and Ellagic acid, for their ability to modulate DNA damage produced by two strong radical oxygen inducers (H2O2 and Bleomycin) in cultured CHO cells. The alkaline Comet assay was used to measure DNA damage and a cytofluorimetric analysis was performed to reveal the intracellular oxidative species. The data showed a marked reduction of H2O2- and Bleomycin-induced DNA damage exerted by Ellagic Acid. On the contrary Ascorbic acid and Melatonin appeared to induce a slight increase in DNA damage per se. In combined treatments, they caused a slight reduction of H2O2-induced damage, but they did not efficiently modulate the Bleomycin-induced one. The Dichlorofluorescein diacetate (DCFH-DA) cytofluorimetric test confirmed the strong scavenging action exerted by Ellagic Acid.

Effects of topical diclofenac (DHEP plaster) on skin, subcutis and muscle pain thresholds in subjects without spontaneous pain

The aim of this study was to determine whether topical application of diclofenac hydroxyethylpyrrolidine (DHEP) modifies somatic pain sensitivity in subjects without spontaneous pain. Twenty male subjects (aged 19-40 years), who had not reported any pain for at least 1 month, underwent measurement of pain thresholds to bilateral electrical stimulation in the quadriceps muscle and overlying subcutis and skin. Following the double-blind study design, one diclofenac adhesive plaster (13 x 10 cm; 180 mg DHEP) was then applied over one quadriceps while a matched placebo plaster was placed contralaterally. Each subject was given two other plasters (diclofenac and placebo) and instructed to substitute those over the quadriceps after 12 h and to wear them for a further 12 h. Thirty minutes after removal of the second plasters, thresholds. were remeasured in all subjects as on the previous day. Thresholds at the first evaluation were within normal range in nine subjects (group 1) and below normal in muscle (hyperalgesia) in the remaining 11 (group 2). No significant changes were observed in skin or subcutis thresholds after diclofenac or placebo treatment in either group. In contrast, muscle thresholds significantly increased after diclofenac compared with placebo treatment (group 1: p < 0.05; group 2: p < 0.007); the increase was significantly higher in group 2 than in group 1 (p < 0.002). Topical application of diclofenac had a selective hypoalgesic effect on muscles, which was more pronounced in the case of hyperalgesia. These results suggest that the preparation is particularly effective in the treatment of algogenic conditions of deep somatic tissues.

[Activation of mandibular growth with the Fräenkel II device: assessment of effects on the vertical plane]

BACKGROUND

The aim of the study was to evaluate if a function Fräenkel II Regulator therapy can increase the vertical dimension of the cranio-facial district. Enlow's cephalometric analysis was used to measure the proportion between cranial and facial components without references to the population average.

METHODS

Twenty patients were selected, with dental class II, skeletal class II and mandibular hypoplasy and normal facial biotype. The patients were treated for 24 months only with Fräenkel II and the appliances was activated 2 mm every 6 months. The follow-up was of the 2 years and cephalometric tracings were made at the beginning and after therapy.

RESULTS

The results showed an increase of vertical dimension and the change of occlusal plane inclination after the therapy. This inclination compensates basal dysarmonies and increases the vertical dimension.

CONCLUSIONS

The results are not statistically significant, but they underline the importance of Fräenkel's regulator function to change negative tendency growth.

How to improve digital dental radiograph reproducibility: an individualized technique

Today, the advantages of the use of digital dental radiography as a valid alternative to conventional techniques are well known. In clinical dental practice, it can be useful to realize intraoral dental x-rays that can be compared, even after some years. The use of a conventional XCP instrument with the "long cone" technique helps to limit image distortion, but the comparison is poor. Moreover, in digital radiography, obtaining almost identical images is essential to superimpose them with dedicated software. The aim of the present work was to obtain fully superimposable and reproducible intraoral digital images through the use of an individual resin positioner. The laboratory phases are all described to create a system that enables exact placement of the digital sensor SIDEXIS (Sirona, Germany) in the mouth of the patient. The authors present a case report where the described technique is applied in the orthodontic field to evaluate molar distalization with a fixed appliance.

Evaluation of genotoxic and cytotoxic properties of pesticides employed in Italian agricultural practices

In a program coordinated by the Italian Ministry of Works, we tested in vitro four pesticides widely employed in a developed agricultural region of central Italy. The four commercial agents were chosen on the basis of their diffusion in agricultural practice, knowledge of their active principle(s), and scant availability of data concerning their toxic and genotoxic activity. The agents were Cirtoxin, Decis, Tramat Combi (TC), and Lasso Micromix (LM). All substances were tested in three in vitro systems: Chinese hamster ovary (CHO) cells, a metabolically competent hamster cell line (Chinese hamster epithelial liver; CHEL), and root tips of Vicia faba (VF). The cytotoxic and genotoxic end points challenged were micronuclei and root tip length (RTL) in VF and mitotic index (MI), proliferation index (PI), cell survival (CS), cell growth (CG), cell cycle length (CCL), sister chromatid exchanges, chromosomal aberrations, and single-cell gel electrophoresis, or comet assay, in CHEL and CHO cells. Tested doses ranged from the field dose up to 200x the field dose to take into account accumulation effects. On the whole, tested agents appear to induce genotoxic damage only at subtoxic or toxic doses, indicating a low clastogenic risk. MI, PI, CS, CG, RTL, and CCL appear to be the less sensitive end points, showing no effects in the presence of a clear positive response in some or all of the other tests. Using cytogenetic tests, we obtained positive results for TC and LM treatments in CHO but not in CHEL cells. These data could be accounted for by postulating a detoxifying activity exerted by this cell line. However, cytogenetic end points appear to be more sensitive than those referring to cytotoxicity.

[Familial variability in the clinical expression of hand-foot-mouth disease]

Aim of the paper is to describe the variability of clinical symptoms in hand, foot and mouth disease, especially among patients belonging to the same family. In spring 1999, during an epidemic of hand, foot and mouth disease, nineteen cases were observed by the authors. In eight cases also some members of the family were affected. A great variability in the clinical expression of the disease, above all among the members of the same family were observed. No cases in children below twelve months or in elderly members of the family were found. Children below three years had more stressed general symptoms, but in no case hospitalization was necessary. Hand, foot and mouth disease does not always show vesicles and aphthae in the affected areas. Clinical expression can also be lacking, but in this case diagnosis can be made easy by the presence of an epidemic or of other cases in the same family.

Site-specific subgingival colonization by Actinobacillus actinomycetemcomitans in orthodontic patients

A high prevalence of Actinobacillus actinomycetemcomitans (Aa) in subgingival plaque in patients for orthodontia already has been observed. The present study had the following aims: 1) to ascertain a direct relationship between the orthodontic appliance placement and the subgingival colonization by Aa, and 2) to determine whether the Aa growth specifically occurred on teeth with braces attached or whether the presence of orthodontic appliances could also cause the isolation of Aa in teeth free from therapeutic appliances. Twenty-four young systemically and periodontally healthy subjects with malaligned and crowded teeth in the anterior sextants of both dental arches participated in this study. After 1 session of ultrasonic scaling with oral hygiene instructions during the first experimental session, the mesiobuccal sites of the first molars and the distobuccal sites of the lateral incisors in both dental arches in each participant were subjected to clinical and microbiologic examination for the recovery of Aa. Clinical examination consisted of recording the presence of plaque and the examination of gingival bleeding on probing and probing depth. Microbiologic sampling was obtained with the insertion of 3 sterile paper points at the deepest part of each gingival sulcus. Altogether, 192 periodontal sites were examined. After the examinations, the patients received fixed orthodontic appliances in only 1 dental arch (test sites) and the other one was left free from appliances (control sites). Clinical examination and microbiologic sampling were repeated in the same experimental test and control sites after 4, 8, and 12 weeks. At the 12-week session, the orthodontic appliance was removed from the test arch, and, 4 weeks later, a further clinical and microbiologic examination was performed. The results showed that, during the period with orthodontic appliances, the presence of plaque scores and the gingival bleeding on probing scores were increased significantly and that Aa, initially absent from all but 1 subject, was isolated in 19 and 20 subjects after 4 and 8 weeks, respectively. Furthermore, no gingival sites from the control teeth (free from Aa colonization at baseline) showed positive results for the sought-after bacterium throughout the entire length of the study. It was concluded that the placement of orthodontic appliances promotes the subgingival growth of Aa; this specific microbial change is specifically restricted to subgingival plaque from orthodontic appliance-bearing teeth. The presence of orthodontic bands and brackets therefore cannot affect the microbiologic condition of the whole mouth.

Inhibitory action of melatonin on H2O2- and cyclophosphamide-induced DNA damage

Melatonin, the pineal gland hormone known for its ability to modulate circadian rhythm, has recently been studied in its several functions. It is believed to inhibit cancer growth, to stimulate the immune system and to act as an antioxidant. In particular, this latter activity is ascribed to two different mechanisms: stimulation of radical detoxifying enzymes and scavenging of free radicals. We used this compound in mammalian cells in vitro to investigate its mechanism of action in modulating DNA damage. Cytogenetic and cytofluorimetric analyses were performed. We show that melatonin is able to modulate chromosome damage (chromosomal aberrations and sister chromatid exchanges) induced by cyclophosphamide. Conversely, its involvement in modulating oxidative processes, thereby reducing DNA damage, is less clear. In particular, melatonin is able to decrease H2O2-induced chromosomal aberrations but not sister chromatid exchanges and has been found to induce oxygen species in a cytofluorimetric test (DCFH assay).

Clinical and experimental study of TMJ distraction: preliminary results

A physiotherapeutic approach, with manual maneuvers and/or distraction appliances, is indicated in the treatment of temporomandibular joint disorders (TMDs) to prevent the progressive fibrosis of the muscle fibers. In this article, the authors report preliminary results of experimental and clinical studies conducted to assess the real effect of distraction in temporomandibular joint disorders. The experimental invivo studies confirmed the structural alteration due to compression and distraction on the capsular and condylar tissues. Clinical cases are reported to show the increase of the intraarticular vertical dimension, with a forward and downward movement of the condyles in a more physiologic condition.

[The clinical and microbiological evaluation of the efficacy of oral irrigation on the periodontal tissues of patients wearing fixed orthodontic appliances]

The aim of the present study has been the evaluation of the effectiveness of oral irrigation with or without toothbrushing and dental flossing, in individuals treated with fixed orthodontic appliances, on controlling the development of dental plaque and, hence, of gingivitis. Eight individuals with a good general and oral status have been chosen. Before the experimental period, they received instructions about oral hygiene with toothbrushing and dental flossing and then they have been monitored to verify they were doing well. At the time T0, the upper tooth have been banded, three Periodontal Indexes (Plaque Index according to Silness and Loe, Modified Gingival Index according to Lobene and Gingival Bleeding Index according to Ainamo and Bay) registered and subgingival plaque samples from the premolars' gingival sulcus collected in order to point out the total anaerobes bacterial counts, the rates of motile bacteria, spirochetes, Gram positive and Gram negative cocci and bacteria, by means of optical and dark field microscopy and of cultural methods. For their oral hygiene, the patients had to use, in the right side toothbrush and dental floss (Control 1), in the left side the oral irrigator alone (Test 1). One month later (time T1), the lower teeth have been banded, too. In the right side the patients had to use toothbrush and dental floss (Control 2), while in the left one they used the same devices as Control 2 plus the oral irrigator (Test 2). At the time T1 Periodontal Indexes and Microbiological analyses have been extended to all the four quadrants.(ABSTRACT TRUNCATED AT 250 WORDS)

[Incidence of enamel fissures in a group of orthodontic patients. In vivo study]

In this paper, the Authors researched the frequence of enamel fissures in a group of 75 individuals. Particular attention was dedicated to the search of such anomalies on teeth treated with multibracket orthodontic appliances, in order to prove a causal nexus between the fissures and the appliances used. After a long term experience, it was found that enamel fissures are a frequent found in almost 60% of the sample examined; moreover, the Authors cannot prove an increment of cracks in subjects treated with multibracket appliances. It was concluded that the whole of the fissures founded, would be considered as preexistent to the positioning of the brackets, even if it cannot be excluded that an excessive torque, or an inadequate debonding technique couldn't produce a mechanical stress on the enamel surface capable to enhance such cracks.

[Clinico-radiographic evaluation of relations between the spinal curve and malocclusion]

Authors examined 36 children with kyphosis, lordosis and malocclusions. Taking also radiographs into account, a statistical study has been done. Three significant correlations were found: between lordosis and ANB, lordosis and SNA and between FR and CV Angle. The last one was a confirmation of a previous study by Solow.