Valorization and extraction of cellulose nanocrystals from North African grass: Ampelodesmos mauritanicus (Diss).

The aim of this research activity was based on the revalorization of Amplodesmos mauritanicus (Diss), an African grass largely presented in the Algerian territory. Diss stems were selected as native botanic material for the extraction of cellulose nanocrystals (CNC). Two different pretreatment steps were carried out to extract CNC from Amplodesmos mauritanicus stems and the following acidic hydrolysis procedure allowed to extract/obtain cellulose nanocrystals in aqueous suspension. The effect of the two different pretreatments, based essentially on chemical or enzymatic treatments, were deeply investigated and the properties compared. Field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) were considered for the characterization of raw material, chemical or enzymatic treated Diss stems and CNC extracted from both chemical and enzymatic pretreated cellulose.

Cholinergic Behavior State-Dependent Mechanisms of Neocortical Gain Control: a Neurocomputational Study.

The embodied mammalian brain evolved to adapt to an only partially known and knowable world. The adaptive labeling of the world is critically dependent on the neocortex which in turn is modulated by a range of subcortical systems such as the thalamus, ventral striatum, and the amygdala. A particular case in point is the learning paradigm of classical conditioning where acquired representations of states of the world such as sounds and visual features are associated with predefined discrete behavioral responses such as eye blinks and freezing. Learning progresses in a very specific order, where the animal first identifies the features of the task that are predictive of a motivational state and then forms the association of the current sensory state with a particular action and shapes this action to the specific contingency. This adaptive feature selection has both attentional and memory components, i.e., a behaviorally relevant state must be detected while its representation must be stabilized to allow its interfacing to output systems. Here, we present a computational model of the neocortical systems that underlie this feature detection process and its state-dependent modulation mediated by the amygdala and its downstream target the nucleus basalis of Meynert. In particular, we analyze the role of different populations of inhibitory interneurons in the regulation of cortical activity and their state-dependent gating of sensory signals. In our model, we show that the neuromodulator acetylcholine (ACh), which is in turn under control of the amygdala, plays a distinct role in the dynamics of each population and their associated gating function serving the detection of novel sensory features not captured in the state of the network, facilitating the adjustment of cortical sensory representations and regulating the switching between modes of attention and learning.

Tricuspid valve repair with the Cosgrove-Edwards annuloplasty system: early clinical and echocardiographic results.

BACKGROUND: The use of flexible rings for tricuspid valve repair is becoming popular. The purpose of this study was to evaluate the Cosgrove-Edwards annuloplasty system for tricuspid regurgitation. METHODS: From June 1998 to December 2000, 22 patients with significant secondary tricuspid regurgitation underwent tricuspid valve repair with the Cosgrove-Edwards annuloplasty system. All patients had disease of left-sided heart valves in addition to tricuspid disease; 34 concomitant procedures were performed. Twenty-one patients (95.5%) were in preoperative New York Heart Association functional class 3 or 4. The mean follow-up was 19.9 +/- 9.7 months. RESULTS: There were two in-hospital nonvalve-related cardiac deaths (9.1%) and one noncardiac death after discharge (4.5%). All survivors were in New York Heart Association functional class 1 or 2; their tricuspid regurgitation was well controlled within grade 1+ and there was a significant reduction of systolic pulmonary artery pressure. Five (83.3%) of the 6 survivors with preoperative pulmonary hypertension had no or trivial residual tricuspid regurgitation. CONCLUSIONS: The Cosgrove-Edwards annuloplasty system is very effective in the treatment of secondary tricuspid regurgitation, also in the presence of pulmonary hypertension.

Marginal bone loss around implants retaining hinging mandibular overdentures, at 4-, 8- and 12-years follow-up.

AIM: The aim of the present study was to study the effect of occlusal factors, oral hygiene, gender and age on the long-term maintenance of alveolar bone height around screw-shaped machined surface commercially pure (c.p.) titanium implants retaining hinging mandibular overdentures. METHOD: In this retrospective study a long-term (4-, 8-, up to 12-years) follow-up of such implant-retained overdentures was performed. From the population of patients so treated at the University Hospital of the Catholic University Leuven, Department of Periodontology and Department of Prosthetic Dentistry, 158 patients were selected on the basis of being treated before March 1994, and the availability of intra-oral radiographs (paralleling technique) present at abutment connection (baseline) and at years 4, 8, and 12. For each patient, all relevant clinical data were recorded, and measurements of marginal bone height around the implants were performed on intra-oral radiographs by means of a digital sliding caliper. RESULTS: Results indicated that only the factor "time" had a significant influence on marginal bone loss. The age and gender of the patients, dental/prosthetic status in the antagonistic jaw, oral hygiene variables, and location of the implants had no significant effect. CONCLUSION: The very high cumulative success rate (97.2%) and limited marginal bone loss (on average 1.7 mm) after 12-years, encourage this kind of treatment using this type of implants.

Care procedures in the healthy full-term newborn infant: a territorial survey.

The Italian Academy of Pediatrics and the Italian Academy of Neonatology have carried out an investigation regarding assistance routines for the healthy full-term newborn. The results confirm a need for modifications in the majority of the centers, especially with regard to Vitamin K prophylaxis which is implemented with extremely variable dosages and not repeated, and to breast-feeding and rooming-in, both of which should be more encouraged. The length of stay in hospital for both vaginal and cesarean deliveries, especially in Lazio, is excessive. Regarding ocular prophylaxis and allergic disease prophylaxis, the attitude is uniform and in agreement with recent literature.

Vallate, foliate and fungiform human papillae gustatory cells. An immunocytochemical and ultrastructural study.

We studied the classifications, topographic distribution and cellular lines of taste bud components in vallate, foliate and fungiform papillae of young, mature and old men with light microscopy, SEM, and TEM. By identifying ultrastructural and immunocytochemical characteristics, three distinct sensorial cells were identified, along with a few basal cells: dark type I cells, light type II cells and light type III cells. These cells extend from the epithelial basal lamina to the gustatory canal, where their apical cytoplasm sends long microvillous expansions. Excluding those of the fungiform papillae-which never go beyond the lower third of the gustatory canal, and are always void of dense substance-the microvillous expansions continue to the external border of the taste pore. Dark type I cells are rich in free ribosomes, tubular RER and large dense granules. Light type II cells with scarce ribosomes and RER, do not have enough peculiar ultrastructural characteristics to be considered effector or phagocyte elements. Light type III cells are characterizes by dense core vesicles whose peculiar ultrastructural characteristics in the foliate and vallate papillae, should be considered a consequence of different functional phases. After comparative evaluation the authors hypothesized on the functional value of some ultrastructural aspects and on the dense core vesicles which are immunoreactive to 5-HT. They observed that all gustatory cells are involved in taste transduction based on behaviours caused by microvilli in the gustatory canal and gustatory cell relationships with nerve endings. Moreover the authors noted that age does not seem to influence taste perception.

Combined curietherapy and surgery in management of stage II.B cervical carcinoma.

The results are presented of ten patients with stage II.B cervical carcinoma, treated with pre-operative after-loading intra-cavitary Iridium 192 followed by radical surgery. The benefits of this combined technique are the reduction of tumor volume, whether in the cervix or in the parametrium. The surgical approach became easier and very few complications were noted. The survival rate after two years follow-up is 100% and no local or distant recurrences have been noted. The following treatment in patients with negative and positive lymph-nodes are discussed.

Primary carcinoma of the vagina. Case report.

An unusual case of Primary Carcinoma of the vagina was recently observed. The patient was treated surgically in 1981 for squamous cervical carcinoma in situ (CIN 3); eight years later the same patient was treated for squamous carcinoma of the vagina that involved the upper, median and lower tract. She was treated with radical colpectomy and VBP chemotherapy for three courses. The pathology, natural history and treatment are discussed.

[Osteocartilaginous neoplasms of the small trochanter: observations on 4 cases]. / Le neoformazioni osteocartilaginee del piccolo trocantere: osservazioni su 4 casi.

The necessity of a surgical approach to the lesser trochanter is fairly rare event that occurs more frequently in the treatment of tumours situated in this anatomical area. The authors described four cases of osteocartilaginous neoplasms situated in proximity of the lesser trochanter. In two cases the mass was removed through a medial surgical approach (Ludloff); in one case through a postcolateral approach (Gibson), in one case through an anterior approach (Smith-Petersen). Each of the used approaches gives a good light on the lesser trochanter, therefore the choice of surgical approach is essentially determined by the prevalent spatial situation of neoplasm. Among the instrumental examinations available the Authors remark the importance of T.A.C. in the spatial visualization of neoformation.

Percutaneous balloon dilatation of calcific aortic valve stenosis: anatomical and haemodynamic evaluation.

Two groups of elderly patients with calcified aortic stenosis were treated by balloon dilatation. In group 1, the valve was dilated just before surgical replacement of the valve. The valvar and annular changes occurring during dilatation were examined visually. In 20 of the 26 patients in this group there was no change. In the six remaining patients mobilisation of friable calcific deposits (1 case), slight tearing of the commissure (4 cases), or tearing of the aortic ring (1 case) were seen. Dilatation did not appear to alter valvar rigidity. In 14 patients (group 2) the haemodynamic gradient across the aortic valve was measured before and immediately after dilatation and one week after the procedure. Dilatation produced an immediate significant decrease of the aortic mean gradient and a significant increase of the aortic valve area. Eight days later the mean gradient had increased and the aortic valve area had decreased. Nevertheless there was a significant difference between the initial gradient and the gradient eight days after dilatation. The initial aortic valve area was also significantly larger than the area eight days after dilatation. The aortic valve gradient rose significantly in the eight days after dilatation and at follow up the gradients were those of severe aortic stenosis.

[Xerography in the study of Achilles paratendinopathies and tendinopathies]. / La xerografia nello studio delle paratendinopatie e tendinopatie achillee.

The authors report their experience in the examination of Achilles tendon, performed with xeroradiography, in 120 young men, affected by Achilles tendon diseases caused by sports. With xeroradiography it is possible to diagnose tendinosis with peritendinitis and pure tendinosis not revealed by clinical examination; radiological diagnostic contribution is particularly important in partial and old ruptures. The necessity is remarked to employ xeroradiography in association with ultrasound to correctly classify the various forms of Achilles tendinopathies and paratendinopathies.

Modified Jones operation in the treatment of pes cavovarus.

The authors describe their technique and results in the treatment of pes cavovarus by transposition of extensor hallucis brevis to the first metatarsal (Jones operation) in association with arthrodesis of the interphalangeal joint of the hallux. In cases of structural deformity it is also combined with osteotomy of the base of the first metatarsal.

The treatment of supracondylar fractures of the humerus in children by closed reduction and fixation with percutaneous Kirschner wires.

The results are reported of 50 consecutive cases of supracondylar fracture of the humerus in children treated by closed reduction and fixation by two parallel percutaneous Kirschner wires. A classification based on clinical and radiological findings is proposed. This is orientated both to treatment and prognosis. The technique of fixation is described and the results of four years experience of this method are reported. The long term results confirm the validity of the method, which has undoubted advantages over traditional methods. Early treatment is essential in cases with neurological or vascular complications.

Evaluation of an automatic oscillometric method and of various cuffs for the measurement of arterial pressure in the neonate.

We compared simultaneous measurement of aortic, direct (Dir) and of indirect (Ind) systolic (S), mean (M) and diastolic (D) arterial pressure (AP) determined by an automatic oscillometric instrument (DINAMAP) in neonates with birthweight of 1000-3680 g. DINAMAP measurements were performed with cuffs of increasing width and length, recommended by the manufacturer for increasing arm circumference, and with a Standard sized cuff (2.5 X 15 cm), previously considered as suitable for neonates of any body size. In addition, we compared simultaneous measurements of Dir SAP and of Ind SAP determined by a Doppler technique and the Standard cuff. In DINAMAP SAP measurements with the Standard cuff, a statistically significant correlation between arm circumference and delta Ind-Dir SAP values (i.e. the difference between simultaneous Ind and Dir SAP measurements) was found. In DINAMAP MAP measurements with the cuff recommended for arm circumference, a statistically significant difference of the mean delta Ind-Dir MAP values was observed in infants whose arm was or was not completely encircled by the bladder of the cuff. In SAP as well as in MAP DINAMAP determinations, the overall error of measurement with the Standard cuff was smaller than with the recommended cuff. The Doppler method was found considerably more accurate than the DINAMAP method for the determination of SAP. In spite of these limitations, the DINAMAP method with the Standard cuff was considered to be reasonably accurate for the clinical determination of SAP and MAP, provided that several consecutive measurements are performed and averaged in order to minimize the error of measurement. When considering DAP measurements the error was so unacceptably high that the DINAMAP method cannot be recommended for clinical use. The need for a careful consideration of the cuff characteristics when evaluating new methods for the indirect measurement of AP in the neonate is emphasized.