Demineralized Human Dentin Matrix as an Osteoinductor in the Dental Socket: An Experimental Study in Wistar Rats.

PURPOSE: This study evaluated the bone-forming potential of the demineralized human dentin matrix by performing histologic and morphometric analyses. The immunolabeling of osteopontin, a determinant protein for bone repair, was also evaluated. MATERIALS AND METHODS: Wistar rats were selected and submitted to the extraction of the right and left second molars. Tooth sockets were separated into two groups: the control group (right), which was filled with the blood clot, and the experimental group (left), which was filled with demineralized human dentin matrix. Animals were sacrificed at 5, 10, and 21 days. Histologic and histoquantitative analyses (analyses of variance [ANOVA] and Tukey's test) were performed, as well as immunostaining for osteopontin as an osteogenesis indicator. RESULTS: After 5 days, demineralized human dentin matrix was incorporated by new trabeculae. After 10 days, connective tissue organization and new trabeculae were observed in the experimental group, and intense staining for osteopontin close to demineralized human dentin matrix was observed in the experimental group. After 21 days, the experimental group was showing mature trabeculae. A statistical difference was observed (P < .05). There was a higher number of trabeculae in the experimental groups in all periods of analysis. The presence of osteopontin was observed more intensely at 10 days close to demineralized human dentin matrix. CONCLUSION: This study indicates that demineralized human dentin matrix implanted in tooth sockets induces the acceleration of osteogenesis.

Warm-Season (C4) Turfgrass Genotypes Resistant to Spittlebugs (Hemiptera: Cercopidae).

Screening for resistance to insect pests is one of the early stages of grass breeding programs. Pasture spittlebugs are sap-sucking insects that potentially cause severe damage to turfgrasses, including the loss of functional quality and perenniallity. The Brazilian flora has a large number of grass species with wide morphological variability and adaptability to different soil and climate conditions that can potentially be used as lawns. However, no study has screened turfgrass genotypes for resistance to spittlebug attack. In this study, we evaluated the intra- and interspecific variability of 35 turfgrass genotypes in the genera Paspalum, Axonopus, and Zoysia for resistance to the pasture spittlebugs, Deois flavopicta (Stal) and Notozulia entreriana (Berg) (Hemiptera: Cercopidae), as measured by damage scores, densities of nymphs and adults, and level of antibiosis resistance. Genotypes were grouped into three groups using cluster analysis and principal component analysis: GroupI had genotypes associated with low damage scores and high density of adult spittlebugs; GroupII had genotypes with intermediate damage scores and low density of nymphs and adults; and GroupIII was formed by genotypes with high damage scores and high nymph density. Intra- and interspecific genotypic variability was related to antibiosis resistance and morphological variation among genotypes with some indicating nonpreference resistance and others indicating tolerance resistance. Our results indicate that besides antibiosis resistance studies, it is essential to evaluate the morphological variability of grass genotypes when screening for resistance to insects. Further studies are needed to elucidate the intraspecific variability of Paspalum notatum Flüggé genotypes for resistance to spittlebug attack.

Hypo-excitability of cortical areas in patients affected by Friedreich ataxia: a TMS study.

The aim of the study was to explore excitability of a motor and a non-motor (visual) area in patients affected by Friedreich ataxia and to correlate neurophysiological data with clinical parameters. Seven patients (3M/4F) and ten healthy controls (5M/5F) participated in the study. The hot-spot for activation of right abductor pollicis brevis was checked by means of a figure-of-eight coil and the motor threshold (MT) on this point was recorded. The phosphene threshold (PT) was measured by means of a focal coil over the occipital cortex as the lower intensity of magnetic stimulation able to induce the perception of phosphenes. The patients showed a significantly higher mean PT (p<.03) and MT values (p<.001) than controls. In all but one patient unable to perceive phosphenes (42% vs. 50% of controls), TMS at 100% intensity did not elicit motor response at rest. The difference in percentage of patients (57.1%) and controls (100%) with motor responses was nearly significant. The size of GAA1 expansion showed significant correlations with PT and MT values. The results of our study showed that FA patients had reduced cortical activation, involving both the motor and the visual cortex. The cortical involvement in these patients seems to be mainly genetically determined. The study provides the first evidence of cortical dysfunction in patients with genetically defined Friedreich ataxia.

The effects of state of alertness on the vestibulo-ocular reflex in normal subjects using the vestibular rotational chair.

Twenty-four subjects with normal vestibular function underwent horizontal sinusoidal harmonic acceleration (SHA) and step-velocity rotational chair assessment twice, first in a heightened state-of-alertness, and second, in a low state-of-alertness. The effects of alertness on vestibulo-ocular reflex gain and time-constant (Tc) were then examined. Although the negative effect on SHA gain had previously been widely reported, the effect on the Tc had not been studied. It was found that SHA gain and step-velocity Tc were significantly and artificially reduced with decreased alertness. On average, SHA gain was reduced by 0.1 at each test frequency and the Tc was reduced from 15.8 seconds to 10.5 seconds. Whilst on average, step-velocity initial gain was only a little affected reducing from 0.53 to 0.49. This very small difference of 0.04 was significant, however, it suggested that this measurement is less affected by patient alertness than SHA gain and Tc.

[Proposal for a computerized record of ergometric tests]. / Proposta di un protocollo computerizzato per i tests ergometrici.

A codified approach to the collection of data obtained from an ergometric test is proposed and the need for such a codification, arising from the necessity to check and organise data collected during clinical examinations, is discussed. Practical questions regarding the chosen model are also discussed. The essential feature is a hierarchy of data enabling information to be represented generally and in detail, a modular structure, in other words, whose basic element is simplicity of compilation and codification.

[An information survey on the automatic operation of intensive therapy units in Italy]. / Indagine conoscitiva sulla gestione automatica delle sale di terapia intensiva in Italia.

A fact finding study was carried out in 58 resuscitation centres and 78 intensive care units to evaluate the current application of computerised techniques in the monitoring and processing of various parameters relating to hospitalised patients. The enquiry revealed a marked interest in the use of computerised systems, particularly in the electrophysiological and haemodynamic field. Promising results were reported from some centres. Some adverse criticisms and points of discussion still exist. International and national experiences matured so far, however, while primarily directed towards scientific research and technological development, open up significant perspectives for the future, for the rational handling of the data collected, and the extension of current knowledge on matters of physiopathology, electrophysiology, and pharmacokinetics.

[Kinetics of beta-methyl-digoxin in different degrees of renal function (author's transl)]. / Cinética de la beta-metil-digoxina en los diversos grados de funcionalismo renal.

Creatinine clearance was evaluated in individuals with varying degrees of renal function following the administration of beta-methyl-digoxin. From the results of the experiment it can be deduced that significantly increased hematic values and renal clearance values definitely lower than normal appear only in patients of a creatinine clearance of less than 50 ml/min. Furthermore, a positive correlation between creatinine clearance values and beta-methyl-digoxin levels was noticed. This correlation was in proportion to the amount of serum albumin. The degree of distribution of free digitalis and digitalis bound to proteins within the vascular system played an important role in the complex kinetics of digoxin. This relationship is suggested as an indirect index of the proportions of free beta-methyl-digoxin and of beta-methyl-digoxin bound to plasma proteins.

[Estimated biological markers of progression in human immunodeficiency virus infection]. / Marqueurs biologiques prévisionnels d'évolution au cours de l'infection par le virus de l'immunodéficience humaine.

The biological markers for determining as early as possible the progression in the infection by the human immunodeficiency virus (HIV) are very important for the health care of patients, and to adapt their anti-retroviral treatment. Among those, four independent biological markers for predicting a pejorative evolution in the following 36 months are used in medical practice: two specific for HIV, p24 antigenemia and serum titre of antibodies to the p24 core antigen, and two non-HIV specific surrogate markers, the beta 2-microglobulinemia and the absolute number of CD4 T cell in blood. P24 antigenemia corresponds to an active retroviral in vivo replication. The cut off for detection is about 10 pg/ml. It is difficult to detect in black people, and in the asymptomatic or pauci-symptomatic stages of the disease. The apparition or the increase of the serum p24 antigen levels suggest the occurrence of opportunistic infections. P24 antigenemia decreases or disappears during the treatment by zidovudine. The diminution or the disappearance of serum antibodies directed to the p24 core protein are secondary to the deficiency of the humoral immunity, and to an increase of the viral replication, which occur at the late stage of the disease. The diminution or the disappearance of serum antibodies to p24 precede the occurrence of AIDS by several months. The increase of the serum beta 2-microglobulin level is associated with the severity of the disease. In the San Francisco prospective cohort, the progression to AIDS in 36 months was 69% when beta 2-microglobulinemia was more than 5 mg/l, 33% when it was between 3.1 to 5 mg/l, and 12% when it was less than 3 mg/l. The beta 2-microglobulin intra-thecal synthesis level could serve as a marker for the specific HIV encephalitis. The CD4 lymphocyte count constitutes an independent provisional marker for progression to AIDS, probably the most important, but mainly of statistical value. A lymphocyte count of 200 CD4/mm3 is considered as the threshold of full blown AIDS. Beside these classic biological markers, numerous other parameters have been evaluated, without knowing their practical interest. Although the predictive markers for AIDS have a real statistical significance, their interpretation could be difficult or hazardous when applied to a sole individual. In a relatively short delay, the actual biological markers will probably be completed or changed, in the routine medical practice, by the use of direct virological markers evaluating the viral load (plasmatic or cellular viremia).

Vena cava filters in hospitalised patients with chronic obstructive pulmonary disease and pulmonary embolism.

In view of the high case fatality rates of patients with chronic obstructive pulmonary disease (COPD) who have pulmonary embolism (PE) we speculated that such patients might benefit from vena cava filters. To test this hypothesis we assessed the database of the Nationwide Inpatient Sample. From 1998-2009, 440,370 patients were hospitalised with PE and COPD who were not in shock or ventilator-dependent and did not receive thrombolytic therapy or pulmonary embolectomy. In-hospital all-cause case fatality rate among those with filters was 5,890 of 68,800 (8.6%) (95% confidence interval [CI] = 8.4-8.8) compared with 38,960 of 371,570 (10.5%) (95% CI = 10.4-10.6) (p<0.0001) who did not receive filters. Case fatality rate was age-dependent. Only those who were older than aged 50 years had a lower in-hospital all-cause case fatality rate with filters. Among such patients, absolute risk reduction was 2.1% (95% CI = 1.9-2.3). The greatest reduction of case fatality rate with vena cava filters was shown in patients >aged 80 years, 11,720 of 81,600 (14.4%) compared with 1,570 of 17,220 (9.1%) (p<0.0001). In conclusion, a somewhat lower in-hospital all-cause case fatality rate was shown with vena filters in stable patients with PE >aged 50 years who also had COPD. The benefit was greatest in elderly patients. The benefit in terms of a decreased case fatality rate would seem to outweigh the risks of vena cava filters in such patients.

Effect of compression stockings on venous blood velocity and blood flow.

The effects of graduated compression stockings (GCS) on venous blood velocity have not been established. In healthy subjects, most investigations showed no effect on blood velocity, but mixed results have been reported. In this investigation we to test the hypothesis that popliteal blood velocity is increased by properly fitted GCS. Time average peak velocity in the popliteal vein, as well as time average mean velocity, vein diameter and mean volumetric flow were measured by pulsed wave Doppler ultrasound in 25 healthy male volunteers without compression stockings and repeated with fitted thigh-length compression stockings. Measurements were obtained while supine and while sitting at rest and during ankle exercise. Thigh-length GCS did not increase popliteal vein blood velocity, diameter, or volumetric blood flow while supine or sitting, with or without ankle exercise.