Anterior Ones Research Articles

Morphological assessments on the arteries of the superior renal segment

The study was performed on 461 renal arteries in order to assess some morphological aspects regarding the arteries that supply the superior renal segment using as study methods: dissection, injection of contrast medium, injection of plastic followed by corrosion together with the examination of MRI and renal angiographies (simple and angio CT). The posterior arteries of the superior renal segment originate mostly from the posterior terminal branch of the renal artery as 1-3 arterial branches. In only 42 cases, we found posterior branches that do not participate in the supply of the superior renal pole. In 190 cases, the anterior arteries of the superior segment originated from the anterior division of the renal artery and in 73 cases directly from the trunk of the renal artery. 34 cases were assessed as a terminal division of the renal artery, while the origin from the posterior division of the renal artery was encountered in 18 cases. In 138 cases, the artery of the superior segment originated from a supplementary renal artery, double (118 cases) or triple (20 cases); in this situation, from the polar artery started the inferior suprarenal artery, except five cases where it originated from the aorta. Of the total of 461 samples, in 244 cases the renal approach was performed above the renal hilum, as proper superior polar arteries and in 217 cases the artery entered through the upper part of the hilum as an apical artery. The morphology of the arteries of the superior renal segment shows a significant degree of variability mostly in what concerns the anterior ones. Frequently we encountered a clear delimitation of the superior renal segment (in 61% of the cases), a situation that allows a relatively facile nephrectomy.

Going Local: Insights from EEG and Stereo-EEG Studies of the Human Sleep-Wake Cycle

In the present paper, we reviewed a large body of evidence, mainly from quantitative EEG studies of our laboratory, supporting the notion that sleep is a local and use-dependent process. Quantitative analyses of sleep EEG recorded from multiple cortical derivations clearly indicate that every sleep phenomenon, from sleep onset to the awakening, is strictly local in nature. Sleep onset first occurs in frontal areas, and a frontal predominance of low-frequency power persists in the first part of the night, when the homeostatic processes mainly occur, and then it vanishes. Upon awakening, we showed an asynchronous EEG activation of different cortical areas, the more anterior ones being the first to wake up. During extended periods of wakefulness, the increase of sleepiness-related low-EEG frequencies is again evident over the frontal derivations. Similarly, experimental manipulations of sleep length by total sleep deprivation, partial sleep curtailment or even selective slow-wave sleep deprivation lead to a slow-wave activity rebound localized especially on the anterior derivations. Thus, frontal areas are crucially involved in sleep homeostasis. According to the local use-dependent theory, this would derive from a higher sleep need of the frontal cortex, which in turn is due to its higher levels of activity during wakefulness. The fact that different brain regions can simultaneously exhibit different sleep intensities indicates that sleep is not a spatially global and uniform state, as hypothesized in the theory. We have also reviewed recent evidence of localized effects of learning and plasticity on EEG sleep measures. These studies provide crucial support to a key concept in the theory, the one claiming that local sleep characteristics should be use-dependent. Finally, we have reported data corroborating the notion that sleep is not necessarily present simultaneously in the entire brain. Our stereo-EEG recordings clearly indicate that sleep and wakefulness can co-exist in different areas, suggesting that vigilance states are not necessarily temporally discrete states. We conclude that understanding local variations in sleep propensity and depth, especially as a result of brain plasticity, may provide in the near future insightful hints into the fundamental functions of sleep.

Congenital Middle Ear Cholesteatoma

Background and Objectives:Congenital middle ear cholesteatoma (CMEC is a keratinous mass behind an intact tympanic membrane. CMEC does not have a history of instrumentation and is less common than acquired one. Many theories have been put forward to explain the pathophysiology of CMEC, however, none of these so far have been convincingly proven. This clinical study was performed to investigate the characteristic features of CMEC and to evaluate the correlation between pathophysiology and CMEC by retrospectivly reviewing the cases. Materials and Method:The medical records of patients who underwent otologic procedures at the hospitals of the Catholic university from January 1993 to September 1998 have been reviewed. They were ten males and four females, ranging in age from 4 to 59 (mean age 18. Results:Three of the 14 patients had the lesions isolated to the anterosuperior quadrant of the mesotympanum which were cystic, easily removed and did not affect hearing. The others had more serious condition with extension into the posterior mesotympanum, which were large, often too extensive to indicate a formative site, and causing ossicular damage. Conclusion:CMEC presents in two distinctive forms according to the site of formation;the anterosuperior and posterior mesotympanum. The review suggest that the pathophysiology of posterior lesions may be different from anterior ones. For early diagnosis of CMEC, screening program should be carried out in children to prevent the more extensive diseases. (Korean J Otolaryngol 1999;42:570-5

Migraine preventive drugs differentially affect cortical spreading depression in rat

Cortical spreading depression (CSD) is the most likely cause of the migraine aura. Drugs with distinct pharmacological properties are effective in the preventive treatment of migraine. To test the hypothesis that their common denominator might be suppression of CSD we studied in rats the effect of three drugs used in migraine prevention: lamotrigine which is selectively effective on the aura but not on the headache, valproate and riboflavin which have a non-selective effect. Rats received for 4 weeks daily intraperitoneal injections of one of the three drugs. For valproate and riboflavin we used saline as control, for lamotrigine its vehicle dimethyl sulfoxide. After treatment, cortical spreading depressions were elicited for 2 h by occipital KCl application. We measured CSD frequency, its propagation between a posterior (parieto-occipital) and an anterior (frontal) electrode, and number of Fos-immunoreactive nuclei in frontal cortex. Lamotrigine suppressed CSDs by 37% and 60% at posterior and anterior electrodes. Valproate had no effect on posterior CSDs, but reduced anterior ones by 32% and slowed propagation velocity. Riboflavin had no significant effect at neither recording site. Frontal Fos expression was decreased after lamotrigine and valproate, but not after riboflavin. Serum levels of administered drugs were within the range of those usually effective in patients. Our study shows that preventive anti-migraine drugs have differential effects on CSD. Lamotrigine has a marked suppressive effect which correlates with its rather selective action on the migraine aura. Valproate and riboflavin have no effect on the triggering of CSD, although they are effective in migraine without aura. Taken together, these results are compatible with a causal role of CSD in migraine with aura, but not in migraine without aura.

On Cultural Materialism, Comics and Digital Media

In 1936,iWalter Benjamin (1892-1940) accounted for the paradigm shift that mechanical reproduction meant for art and politics. For Benjamin, technological change was not merely a sign of uncomplicated, forward-thinking progress; it meant a profound transformation of the realm of human experience. In this account of the era Benjamin witnessed, the German philosopher and collector was also unknowingly predicting a time he personally would not experience: four decades later, these descriptions of his time are illuminating the reality of the present. Benjamin wrote that ‘the cathedral leaves its locale to be received in the studio of a lover of art; the choral production, performed in an auditorium or in the open air, resounds in the drawing room’, but he was not describing digital 3D imaging, Wikipedia, YouTube or Google; he was writing about film photography and the phonograph, forms of technology many now consider ‘obsolete’. The fact we can identify that sense of wonder at technology’s ability to make the absent present and vice versa proves Benjamin’s point: that there is a ‘logic of form’ in art and technology, or, in other words, that the future and the present are also contained in the past, as new technologies and art forms do not simply supersede present and anterior ones, but depend on them. Benjamin's work has proven so influential because, unlike the digital media ‘pundits’ of today, he did not predict the future, but analysed the present.

Surgically-Assisted Rapid Canine Orthodontic Distraction

Purpose: Treatment of dental crowding includes extraction of premolar teeth and retraction of anterior ones including the canines. Time required for canine distalization using traditional orthodontic techniques varies between 6 to 9 months. “Dental distraction” with combined surgical and rapid postoperative orthodontic treatment can possibly shorten the treatment time required for canine distalization.

Morpho-Anatomy and Ontogeny of the Floral Nectaries ofCardiospermum grandiflorumandUrvillea chacoensis(Sapindaceae)

The morphology, anatomy and ontogeny the floral nectaries of two species of Sapindaceae (Paullinieae), viz. Cardiospermum grandiflorum and Urvillea chacoensis, were studied using light and scanning electron microscopy. Both species are monoecious with oblique monosymmetric flowers. The floral nectaries are located at the base of the androgynophore. Vascular tissue supplying the nectaries consists of phloem. Cardiospermum grandiflorum has a posterior nectary with two lobes without any specially differentiated tissue, and with nectarostomata. In Urvillea chacoensis the nectary has four lobes; two posterior ones with distinctive nectariferous tissue with nectarostomata on the abaxial side, and two minor anterior ones that are histologically similar but lack nectarostomata. The nectaries in both species have a common base with the petals. Since the nectaries are macroscopically differentiated they are considered as structural nectaries.

Parietal modules for reaching

Optic ataxia (OA) is classically defined as a deficit of visually guided movements that follows lesions of the posterior part of the posterior parietal cortex (PPC). Since the formalisation of the double stream of visual information processing [Milner, A. D., & Goodale, M. A. (1995). The visual brain in action. Oxford: Oxford University Press] and the use of OA as an argument in favour of the involvement of the posterior parietal cortex (dorsal stream) in visually guided movements, many studies have looked at the visuomotor deficits of these patients. In parallel, the development of neuroimaging methods have led to increasing information about the role of the posterior parietal cortex in visually guided actions. In this article, we discuss the similarities and differences in the results that emerged from these two complementary viewpoints by combining a meta-analysis of neuroimaging data on reaching with lesion studies from OA patients and results of our own fMRI study on reaching in the ipsi- and contra-lateral visual field. We identified four bilateral parietal foci from the meta-analysis and found that the more posterior foci showed greater lateralisation for contralateral visual stimulation than more anterior ones Additionally, the more anterior foci showed greater lateralisation for the use of the contralateral hand than the more posterior ones. Therefore, we can demonstrate that they are organised along a postero-anterior gradient of visual-to-somatic information integration. Furthermore, from the combination of imaging and lesion data it can be inferred that a lesion of the three most posterior foci responsible for the target-hand integration could explain the hand and field effect revealed in OA reaching behaviour.

‘Four-leaflet clover repair’ of severe tricuspid valve regurgitation due to complex lesions

We report the case of a 52-year-old man who was referred to surgery because of severe mitral and tricuspid regurgitation of Barlow's disease. In particular, the tricuspid valve was a 'four-leaflet valve' due to the presence of a small accessory leaflet between the septal and the posterior leaflets. The valve insufficiency was determined by prolapse of all leaflets (in particular of the anterior and posterior ones) associated with annular dilatation. The patient underwent both mitral and tricuspid valve repair. The tricuspid regurgitation was corrected by stitching together the middle point of the free edges of the tricuspid leaflets producing a 'four-leaflet clover-shaped' valve. Surgical and echocardiographic images of the repaired valve are reported.

A biomechanic research into interosseous talocalcaneal ligaments

Objective To observe the biomechanics of the anterior and posterior interosseous talo-calcaneal ligaments (ITCLs) . Methods Load-displacement characteristics of the subtalar joint were studied in 12 cadaver specimens whose ankle joints were mutilated. The ankle articular surfaces of the talus and the post-calcaneus were exposed. Bone blocks were then embedded in polymethylmethacrylate. The an-terior ITCLs were abscised in 6 of them, and the posterior ITCLs in the other 6. A multi-functional biome-chanical machine was used to perform the biomechanical tests on the specimens. Results When the anterior ITCLs were cut, the tali moved to the anterior-lateral side. When the posterior ITCLs were cut, the tali mostly moved to the anterior-interior side. Conclusions The anterior and posterior ITCLs have dif-ferent roles in maintaining stability of the subtalar joint. Since the posterior ITCLs seem more important than the anterior ones, they should have priority in ITCL reconstruction. Key words: Subtalar; Ligament ; Biomechanies

When can local excision be considered adequate for treatment of non advanced low rectal cancer (NALRC)?

One major issue in local excision of NALRC is the extent and depth of tissue excision. In the last decade several improvements have occurred in the diagnosis and treatment of NARLC, including new imaging techniques (MRI with new specific contrast agents), neoadjuvant therapy and Transanal Endoscopic Microsurgery (TEM). Surgeons who are experienced with local excision of rectal cancer both by TEM and by traditional excision techniques know that this extent may be variable. An adequate local excision specimen should look like a truncated pyramid and including 1 cm of normal mucosa around the tumor with the base corresponding to the mesorectal fascia (“holy plane”) for posterior lesions, and the prostatic capsule or vagina for anterior ones. The volume of excised tissue should not be less than 60 cc. In a consecutive series of 210 pT0-1-2-3 N0 G1-2 rectal cancer patients the local recurrence rate and probability of survival at 90 months of follow up were 5% and 89%, respectively, after neoadjuvant therapy and TEM. 1 Electrocoagulation spots at one cm distance around the tumor after neoadjuvant radiochemotherapy. 2 Prostatic capsule after excision of an anteriorly located lesion. 3 Posterior wall of the vagina after excision of a tumor located on the left lateral wall of the rectum. 4 Excisional area. 5 The oral margin of the defect is removed for frozen section examination. 6 The aboral margin of the defect is removed for frozen section examination. 7 The oral margin of the defect is pulled caudally to start the suture. 8 Closure of the defect is completed with three continuous sutures and silver clips. 1 2

The anatomy of the proximal ulna

The posterior border of the ulna is the most important bony landmark for all dorsal surgical approaches and the guideline for open reduction, internal fixation of displaced comminuted fractures of the proximal ulna. We examined 74 cadaveric specimens to evaluate the anatomy of the proximal ulna, especially the course of the posterior border, the point of varus angulation, the width of the shaft, and the relationship of the posterior border to the interosseous and anterior ones. In 63 specimens, the mean point of varus angulation was 85.4 mm, and the average angulation angle was 17.7 degrees. In 11 specimens, the posterior border was either radially bowed or the bow was poorly defined and not localized to a specific area along the length of the bone. In conclusion, the variations of the proximal ulna have to be considered if dorsal plates and intramedullary screws are used.

An almost complete skeleton of Metailurus parvulus (Carnivora, Felidae) from the late Miocene of Kerassia (Northern Euboea, Greece)

We describe a partial skeleton of Metailurus parvulus from the Turolian site of Kerassia 1 (Northern Euboea, Greece). The material, which consists of a mandible, the anterior and posterior limb-bone elements, some sternal bones and some vertebrae, is the most complete known of this species. The dental material is compared to specimens from Pikermi and Chomateri (Greece), and China. The limb-bones available offer us the possibility to discuss the status of some previously described specimens from Pikermi. The limb proportions indicate that M. parvulus had elongated posterior limbs relative to the anterior ones, which reflects developed jumping skills. M. parvulus had moderately developed cursorial abilities, intermediate between open and closed habitat felids, and probably frequented primarily relatively open woodlands.

Her1 and her13.2 are jointly required for somitic border specification along the entire axis of the fish embryo

Delta-Notch and FGF signaling are involved in the control of somitogenesis in zebrafish. her genes are generally known as downstream targets of Delta-Notch signaling, but the her13.2 gene from zebrafish has recently been shown to depend on FGF signaling only. We have here studied the functional role of her13.2 in conjunction with her genes that are under Delta-Notch control. We show that joint inactivation of her1 and her13.2 leads to a complete loss of all somitic borders, including the most anterior ones. This somitic phenotype is much stronger than would be expected from the effects of the inactivation of either gene alone. A joint inactivation of her13.2 and her7, which is a paralogue of her1, does not show this enhanced effect. Thus, our results confirm inferences from in vitro studies that her1 and her13.2 form specific heterodimers, which may directly be required for regulating further target genes. These two her genes thus constitute the link between Delta-Notch pathway and FGF signaling during entire somitogenesis. We show that this interaction is conserved in the rice fish medaka, as a joint inactivation of the respective orthologues leads also to the same phenotype as in zebrafish. In addition, our results suggest that the mechanisms for anterior and posterior somite formation are not principally different, although the anterior somites often seem more refractory to genetic perturbations.

Evidence of Functional Connectivity between Auditory Cortical Areas Revealed by Amplitude Modulation Sound Processing

The human auditory cortex includes several interconnected areas. A better understanding of the mechanisms involved in auditory cortical functions requires a detailed knowledge of neuronal connectivity between functional cortical regions. In human, it is difficult to track in vivo neuronal connectivity. We investigated the interarea connection in vivo in the auditory cortex using a method of directed coherence (DCOH) applied to depth auditory evoked potentials (AEPs). This paper presents simultaneous AEPs recordings from insular gyrus (IG), primary and secondary cortices (Heschl's gyrus and planum temporale), and associative areas (Brodmann area [BA] 22) with multilead intracerebral electrodes in response to sinusoidal modulated white noises in 4 epileptic patients who underwent invasive monitoring with depth electrodes for epilepsy surgery. DCOH allowed estimation of the causality between 2 signals recorded from different cortical sites. The results showed 1) a predominant auditory stream within the primary auditory cortex from the most medial region to the most lateral one whatever the modulation frequency, 2) unidirectional functional connection from the primary to secondary auditory cortex, 3) a major auditory propagation from the posterior areas to the anterior ones, particularly at 8, 16, and 32 Hz, and 4) a particular role of Heschl's sulcus dispatching information to the different auditory areas. These findings suggest that cortical processing of auditory information is performed in serial and parallel streams. Our data showed that the auditory propagation could not be associated to a unidirectional traveling wave but to a constant interaction between these areas that could reflect the large adaptive and plastic capacities of auditory cortex. The role of the IG is discussed.

Comparison of Influenceon Displaced Femoral Neck Fractures in Young Adults: Fracture Level and Comminution, Time to Operation and Reduction

Purpose : To analyze the influences of fracture level and comminution, time to operation and reduction quality on the results of displaced femoral neck fractures in young adults. Materials and Methods: From January 1996 to January 2003, 39 of 51 cases of displaced femoral neck fractures that were treated with closed reduction and percutaneous internal fixation using cannulated screws, were evaluated after at least two years of follow-up with respect to the fracture level, comminution, time to operation, and reduction quality. Results : The incidence of AVN and non-union were 6/39 (15.4%) and 3/39 (7.7%), respectively. The differences in the incidences of complications among subcapital, transcapital, and subcapital fractures was not significant (p=1 & p=1). There was a higher incidence of AVN (p=0.0066) and non-union (p=0.0219) with posterior comminutions than anterior ones. The time to operation was not an important factor in influencing the development of complications (p=0.4984 & p=1). Between acceptable and poor reductions, the differences in the incidences of AVN was significant (p=0.0105), but not in the incidences of non-unions (p=0.1011). Conclusion : We concluded that good quality of reduction is more important than the time to operation for achieving good results, and that comminution is a more important prognostic factor than is the fracture level.

Requirement ofabdominal-AandAbdominal-Bin the developing genitalia ofDrosophilabreaks the posterior downregulation rule

The genitalia of Drosophila derive from the genital disc and require the activity of the Abdominal-B (Abd-B) Hox gene. This gene encodes two different proteins, Abd-B M and Abd-B R. We show here that the embryonic genital disc, like the larval genital disc, is formed by cells from the eighth (A8), ninth (A9) and tenth (A10) abdominal segments, which most likely express the Abd-B M, Abd-B R and Caudal products, respectively. Abd-B m is needed for the development of A8 derivatives such as the external and internal female genitalia, the latter also requiring abdominal-A (abd-A), whereas Abd-B r shapes male genitalia (A9 in males). Although Abd-B r represses Abd-B m in the embryo, in at least part of the male A9 such regulation does not occur. In the male A9, some Abd-B m(-)r(-) or Abd-B r(-) clones activate Distal-less and transform part of the genitalia into leg or antenna. In the female A8, many Abd-B m(-)r(-) mutant clones produce similar effects, and also downregulate or eliminate abdominal-A expression. By contrast, although Abd-B m is the main or only Abd-B transcript present in the female A8, Abd-B m(-) clones induced in this primordium do not alter Distal-less or abd-A expression, and transform the A8 segment into the A4. The relationship between Abd-B and abd-A in the female genital disc is opposite to that of the embryonic epidermis, and contravenes the rule that posteriorly expressed Hox genes downregulate more anterior ones.

UEFA Champions League study: a prospective study of injuries in professional football during the 2001–2002 season

Background: No previous study on adult football involving several different countries has investigated the incidence and pattern of injuries at the highest club competitive level. Objective: To investigate the risk...

Angiographic study of the tibioperoneal trunks in patients with aorto-iliac occlusive disease

Knowledge of the normal anatomic characterization of the popliteal artery and its branches is essential as a guide in vascular surgery below the knee. Using radiologic, digital and statistical methods tibioperoneal trunks were studied on 76 preoperative arteriograms, visualizing bilateral configurations of the popliteal artery division, from 46 men and 30 women, with aorto-iliac occlusive disease. The aim of this study has been to evaluate tibioperoneal trunks as to typological (types, frequency of existence, gender and syntopic dimorphisms) and angiometric (length, internal diameter and capacity) aspects. The statistical analysis of tibioperoneal trunks (types, angiometric parameters) did not reveal any gender or syntopic dimorphisms (p > or = 0.05). In both the posterior tibioperoneal trunk (89.47%) or the anterior tibioperoneal trunk (7.89%) short and long ones were found. High correlation coefficients of the symmetry of the left and right vascular patterns were observed (r = 0.80-0.83). In 2.64% of cases tibioperoneal trunks were absent. Two types of posterior tibioperoneal trunk were longer (p < or = 0.01) but they were thinner (p < or = 0.05) than similarly named types of anterior tibioperoneaL trunk. In anterior and posterior tibioperoneal trunks of the short type the diameter of the vessel was statistically larger (p < or = 0.05) than in its long type. The largest capacity was found in the long type and the smallest in the short type of anterior tibioperoneal trunk (p < or = 0.01). These findings have implications in vascular grafting below the knee.

Topographic aspects of photic driving in the electroencephalogram of children and adolescents.

The electroencephalogram amplitude spectra at 11 fixed frequencies of intermittent photic stimulation of 3 to 24 Hz were combined into driving "profiles" for 14 scalp points in 8 male and 7 female normal subjects aged 9 to 17 years. The driving response varied over frequency and was detected in 70 to 100% of cases in the occipital areas (maximum) and in 27 to 77% of cases in the frontal areas (minimum) using as a criterion peak amplitude 20% higher than those of the neighbors. Each subject responded, on average, to 9.7 +/- 1.15 intermittent photic stimulation frequencies in the right occipital area and to 6.8 +/- 1.97 frequencies in the right frontal area. Most of the driving responses (in relation to the previous background) were significant according to the spectral F-test (alpha = 0.05), which also detected changes in some cases of low amplitude responses not revealed by the peak criterion. The profiles had two maxima in the alpha and theta bands in all leads. The latter was not present in the background spectra in the posterior areas and was less pronounced in the anterior ones. The weight of the profile theta maximum increased towards the frontal areas where the two maxima were similar, while the profile amplitudes decreased. The profiles repeated the shape of the background spectra, except for the theta band. The interhemispheric correlation between profiles was high. The theta driving detected in all areas recorded suggests a generalized influence of the theta generators in prepubertal and pubertal subjects.