Modifications in the surgical correction of trigonocephaly

A modified technique for the surgical correction of trigonocephaly is presented. The technical modifications are designed both to increase the stability of fixation of the supraorbital bar and lateral canthal advancements and to increase interorbital distance and anterior cranial fossa volume when utilized in those patients who exhibit the full expression of trigonocephaly, including midline ridging, bifrontal recession, hypotelorbitism, shortened anterior cranial fossa, deficient projection of lateral orbit, and bitemporal narrowing. It is a modification of the supraorbital bar remodeling/advancement procedure as originally described by Marchac with the introduction of a nasofrontal osteotomy and superior osteotomy bone graft and midline miniplate fixation of the supraorbital bar to the nasofrontal junction. Its use in 20 patients has been favorable.     

Load transmission in the nasofrontal suture of the pig, Sus scrofa

The nasofrontal suture links the nasal complex with the braincase and is subject to compressive strain during mastication and (theoretically) tensile strain during growth of nasal soft tissues. The suture's ability to transmit compressive and tensile loads therefore affects both cranioskeletal stress distribution and growth. This study investigated the in vitro viscoelastic and failure properties of the nasofrontal suture in the pig, Sus scrofa. Suture specimens from two ages were tested in compression and tension and at fast and slow rates. In additional specimens, strain gauges were applied to the suture and nasal bone for strain measurement during testing. Relaxation testing demonstrated higher elastic moduli in tension than compression, regardless of test rate or pig age. In contrast, maximum elastic moduli from failure tests, as well as peak stresses, were significantly higher in compression than in tension. Sutures from older pigs tended to have higher elastic moduli and peak stresses, significantly so for tensile relaxation moduli. Strain gauge results showed that deformation at the suture was much greater than that of the nasal bone. These data demonstrate the viscoelasticity and deformability of the nasofrontal sutural ligament. The suture achieved maximal resistance to tensile deformation at low loads, corresponding with the low tensile loads likely to occur during growth of nasal soft tissues. In contrast, the maximal stiffness in compression at high loads indicates that the suture functions with a substantial safety factor during mastication.     

Craniofacial sutures: morphology, growth, and in vivo masticatory strains.

The growth and morphology of craniofacial sutures are thought to reflect their functional environment. However, little is known about in vivo sutural mechanics. The present study investigates the strains experienced by the internasal, nasofrontal, and anterior interfrontal sutures during masticatory activity in 4-6-month-old miniature swine (Sus scrofa). Measurements of the bony/fibrous arrangements and growth rates of these sutures were then examined in the context of their mechanical environment. Large tensile strains were measured in the interfrontal suture (1,036 microepsilon +/- 400 SD), whereas the posterior internasal suture was under moderate compression (-440 microepsilon +/- 238) and the nasofrontal suture experienced large compression (-1,583 microepsilon +/- 506). Sutural interdigitation was associated with compressive strain. The collagen fibers of the internasal and interfrontal sutures were clearly arranged to resist compression and tension, respectively, whereas those of the nasofrontal suture could not be readily characterized as either compression or tension resisting. The average linear rate of growth over a 1-week period at the nasofrontal suture (133.8 micrometer, +/- 50.9 S.D) was significantly greater than that of both the internasal and interfrontal sutures (39.2 micrometer +/- 11.4 and 65. 5 micrometer +/- 14.0, respectively). Histological observations suggest that the nasofrontal suture contains chondroid tissue, which may explain the unexpected combination of high compressive loading and rapid growth in this suture.     

Evidence for a peripheral mechanism of esophagocrural diaphragm inhibitory reflex in cats

The esophagogastric junction (EGJ) is guarded by two sphincters, a smooth muscle lower esophageal sphincter (LES) and a skeletal muscle crural diaphragm. These two sphincters relax simultaneously under certain physiological conditions, i.e., swallowing, belching, vomiting, transient LES relaxation, and esophageal distension. Esophageal distension-induced crural diaphragm relaxation is mediated through vagal afferents that are thought to exert inhibitory influence on the central mechanism (brain stem) of crural diaphragm contraction. We conducted studies in 10 cats to determine whether a mechanism of crural diaphragm relaxation was located at the level of the neuromuscular junction and/or muscle. Stimulation of the crural diaphragm neuromuscular junction through 1) the electrodes implanted in the muscle and 2) the bilateral phrenic nerve resulted in an increase in EGJ pressure. Nicotinic receptor blockade (pancuronium, 0.2 mg/kg) abolished the EGJ pressure increase caused by electrical stimulation of the neuromuscular junction. Esophageal distension and bolus-induced secondary esophageal peristalsis caused relaxation of the EGJ during the stimulation of the neuromuscular junction. Bilateral phrenicotomy and vagotomy had no influence on this relaxation. These data suggest the existence of a peripheral mechanism of crural diaphragm inhibition. This peripheral inhibitory mechanism may reside at the level of either the neuromuscular junction or the skeletal muscle.     

白暨豚上呼吸道的解剖和组织学的研究

白鱀豚上呼吸道具有前庭囊、鼻额囊及前颌囊三对气囊,没有副囊和连接囊。三对囊均右大于左,其中又以前庭囊最为显著。喉由甲状软骨、环状软骨、会厌软骨及一对杓状软骨组成,从喉腔壁的组织学观察发现有室皱襞(假声带)的存在。       

Hermitian splines for modeling biological soft tissue systems that exhibit nonlinear force-elongation curves

Numerical simulation of soft tissue mechanical properties is a critical step in developing valuable biomechanical models of live organisms. A cubic Hermitian spline optimization routine is proposed in this paper to model nonlinear experimental force-elongation curves of soft tissues, in particular when modeled as lumped elements. Boundary conditions are introduced to account for the positive definiteness and the particular curvature of the experimental curve to be fitted. The constrained least-square routine minimizes user intervention and optimizes fitting of the experimental data across the whole fitting range. The routine provides coefficients of a Hermitian spline or corresponding knots that are compatible with a number of constraints that are suitable for modeling soft tissue tensile curves. These coefficients or knots may become inputs to user-defined component properties of various modeling software. Splines are particularly advantageous over the well-known exponential model to account for the traction curve flatness at low elongations and to allow for more flexibility in the fitting process. This is desirable as soft tissue models begin to include more complex physical phenomena.     

"Keystone" approach for intracranial nasofrontal dermoid sinuses

Nasofrontal dermoid sinus tracts that extend intracranially through the foramen cecum or ethmoid can be difficult to completely resect. Complete extirpation of nasofrontal dermoid sinus cysts is essential for effective treatment of this problem to minimize the chance of recurrence. The authors describe a new technique based on parasagittal osteotomies through the supraorbital bar, or bandeau, that ensures that the resection of the nasofrontal dermoid sinus cysts is complete. This technique also limits the size of the external nasal incision and enhances the surgeon's exposure of the anterior cranial base for resection of intradural extension. This approach also enhances exposure for the direct repair of the dura and the cranial vault.     

Factors promoting infestation of newly planted, nonbearing apple orchards by dogwood borer (Lepidoptera: Sesiidae)

The initiation and level of infestation by dogwood borer, Synanthedon scitula (Harris), was tracked over three consecutive years in two nonbearing apple (Malus spp.) orchards in West Virginia and Virginia. The orchards were planted on a number of rootstock-variety (approximately cultivar) combinations and grown using different cultural practices. Infestations were detected during the first season after planting and continued to increase annually. The amount of burr knot tissue had the greatest impact on dogwood borer populations, because increasing amounts of burr knot tissue resulted in higher infestation rates. The use of plastic spiral wrap tree guards seemed to increase the development of burr knot tissue, resulting in significantly greater infestation compared with trees without tree guards in the West Virginia orchard. Variety also had a significant effect, because 'Idared' trees on M.26 had significantly greater levels of infestation compared with 'Buckeye Gala' on M.26, with or without tree guards, in the Virginia orchard. Mounding soil around the rootstock to a height just above the graft union prevented or tremendously curtailed infestation by dogwood borer, but it led to scion rooting that seemed to have an impact on size-controlling features of dwarfing rootstocks. Removal of the mounds at the beginning of the third growing season resulted in infestation of the rooted tissue during the same season. As long as apple cultivars continue to be planted on size-controlling rootstocks, dogwood borer will likely remain a serious pest, requiring either chemical treatments or a behavioral control strategy, such as mating disruption, to protect trees from infestation and damage.     

Extended vomer flaps in cleft palate repair: a preliminary report

It is the author's belief that poor healing due to deficient mesenchyme at the junction of the hard and soft palates probably constitutes the essential reason for some failures of palatoplasty. In order to provide extra tissue to reinforce the above-mentioned region and to facilitate efficient velar lengthening, the use of an extension of the vomer flap detached from the roof of the pharynx is proposed. Such extended vomer flaps have been applied successfully both on the oral and nasal sides in 50 patients. The necessity of further and longer observations is obvious.     

Interaction Between Puccinia xanthii and Facultative Parasitic Fungi on Xanthium occidentale

The present study was undertaken to evaluate the possible interactions between Puccinia xanthii and facultative parasitic fungi isolated from plants of the Noogoora burr complex. Six different Colletotrichum spp., a Phomopsis sp. and Alternaria zinniae, the latter a potential bioherbicide for Xanthium weeds, were tested. Alternaria zinniae caused necrotic lesions of leaf and stem on healthy and rust-infected Noogoora burr plants and did not specifically infect rust lesions. Most Colletotrichum spp. infected Noogoora burr via leaf and stem rust lesions. The infected lesions of P. xanthii became necrotic and the pustules did not reach maturity. Colletotrichum orbiculare was the only facultative parasite able to grow beyond the rust lesions into the surrounding tissue, girdle the stem, and consequently kill the plant tissue above. Colletotrichurn orbiculare did not infect plants previously infected by A. zinniae. The possible additive or synergistic adverse effects of the rust and the facultative parasitic fungi on the Noogoora burr complex offer new avenues to explore for biological control.     

The depressed nasofrontal angle in aesthetic rhinoplasty

Certain patients seeking cosmetic rhinoplasty present with a so-called depressed nasofrontal angle. In this condition, the most careful part of the nasal bone is underdeveloped. This gives the illusion of a nasal hump. Complete removal of this hump will create a hypoplastic nose. Partial reduction of the hump and augmentation in the nasofrontal area are indicated in these patients. Autogenous material is preferable for this purpose. A number of patients are presented with illustration of the technique.     

Indirect evidence that guarded quiescent deutonymph females invest energy to attract conspecific males in the Kanzawa spider mite (Acari: Tetranychidae)?

Because only the first mating results in fertilization in Tetranychus kanzawai (Acari: Tetranychidae), adult males guard quiescent deutonymph females (i.e., precopulatory mate guarding). A previous study reported that quiescent deutonymph females guarded by a male attract more conspecific males than solitary females and then hypothesized that guarded females release more chemical signals than solitary ones to attract males. Quiescent deutonymph females do not feed. If the hypothesis is appropriate, guarded females should invest energy in attracting males at the expense of investment in other activities, such as egg production. Therefore, we compared oviposition rates immediately after adult emergence between guarded females and solitary females. On the first day, the oviposition rate of guarded females was lower than that of solitary females. On the second day, however, there was no significant difference between female groups. These results suggest that guarded females invest energy in activities other than egg production before adult emergence and that the energetic cost is easily recoverable. We believe that our finding indirectly supports the hypothesis that guarded females release more chemical signals than solitary females to attract conspecific males.     

The effect of unilateral partial facial paralysis on nasofrontal sutural growth: an experimental study in the rabbit.

In a previous study in the rabbit, it was demonstrated that paralysis of the midfacial musculature results in decreased anteroposterior growth of the snout. At the end of growth, these animals showed macroscopically striking similarities to animals with unilateral fusion of the nasofrontal suture. In this study, whether nasofrontal sutural growth is unilaterally restricted in animals with unilateral partial facial paralysis was investigated. A left-sided partial facial paralysis was induced in sixteen 12-day-old New Zealand White rabbits. At the ages of 5, 9, 12, and 17 weeks, four animals were randomly assigned to be killed for analysis of nasofrontal sutural growth. In each animal, the left experimental side was compared with the right control side. By means of histomorphometric measurements, it was shown that diminished sutural growth activity was present on the left paralyzed side in periods of rapid growth. On the other hand, no significant alterations in sutural width were found. These findings seem to explain some of the macroscopic growth alterations (i.e., diminished anterior maxillary length) observed in rabbits with unilateral partial facial paralysis.     

Deformation of nasal septal cartilage during mastication

The cartilaginous nasal septum plays a major role in structural integrity and growth of the face, but its internal location has made physiologic study difficult. By surgically implanting transducers in 10 miniature pigs (Sus scrofa), we recorded in vivo strains generated in the nasal septum during mastication and masseter stimulation. The goals were (1) to determine whether the cartilage should be considered as a vertical strut supporting the nasal cavity and preventing its collapse, or as a damper of stresses generated during mastication and (2) to shed light on the overall pattern of snout deformation during mastication. Strains were recorded simultaneously at the septo‐ethmoid junction and nasofrontal suture during mastication. A third location in the anterior part of the cartilage was added during masseter stimulation and manipulation. Contraction of jaw closing muscles during mastication was accompanied by anteroposterior compressive strains (around ?1,000 με) in the septo‐ethmoid junction. Both the orientation and the magnitude of the strain suggest that the septum does not act as a vertical strut but may act in absorbing loads generated during mastication. The results from masseter stimulation and manipulation further suggest that the masticatory strain pattern arises from a combination of dorsal bending and/or shearing and anteroposterior compression of the snout. J. Morphol., 2009. © 2009 Wiley‐Liss, Inc.     

Cephalometric and anthropomorphic observations of Binder's syndrome: a study of 19 patients

Binder's syndrome (maxillonasal dysplasia) is a disorder characterized by nasomaxillary hypoplasia. To ascertain the extent of underdevelopment of the midfacial skeleton and soft tissues, 19 of 29 patients with Binder's syndrome were retrospectively evaluated, both with cephalometry and anthropometry. Ten females and nine males were placed collectively into three age groups: 6 years, 10 years, and 16 to 17 years. Cephalometric measurements disclosed a short anterior cranial base (S-N), a normal length of the vertical maxilla (SE-PNS), a decreased horizontal maxilla (PNS-A, Co-A), a recessed orbitale (SNO), and a high-normal mandibular length (Co-Gn). Anthropometry revealed a large nasofrontal angle, acute nasal inclination and nasolabial angle, decreased nasal prominence (Sn-Prn), a decreased columellar length (C-Sn), and a normal vertical nose (N-Sn) and upper lip (Sn-Sto) length.     

The guard honey bee: ontogeny and behavioural variability of workers performing a specialized task

Guarding is a relatively unstudied aspect of honey bee, Apis mellifera L., worker behaviour. The aim of this study was to characterize quantitatively the ontogeny and individual variability of guarding behaviour, the allocation of workers to the guard population in a colony, and the intercolonial variability of guarding behaviour. Guarding is a discrete task performed by a distinct group of workers that are younger than foragers and older than house bees. Workers that guarded initiated the behaviour between the ages of 7 and 22 days. The mean age of the onset of guarding varied; the minimum mean age of guards for a colony was 13·6 days and the maximum was 16·0 days. Workers varied in the length of time they spent as a guard. Most bees guarded for less than 1 days; however, some guarded up to 6 consecutive days. The more time a bee spent guarding during a day the more likely that bee was to guard for more than 1 day. Bees that guarded for more than 1 day also had longer and more frequent individual guarding bouts. All colonies that were studied had guard populations, but not all workers guarded. A relatively small proportion of any age cohort was observed to guard. The percentage of an age cohort that guarded varied among colonies, as did the size of the guard population. Guarding is a specialized task in that few bees guard, but guarding does not appear to require experience because so few bees remained as guards for very long. There was intercolonial variation in all aspects of the ontogeny of guarding and in allocation of workers to guarding. This variation is discussed in the light of other studies of variation in worker behaviour.     

Frontal sinus fractures: guidelines to management

The appropriate management of frontal sinus fractures is controversial. Experience with 78 frontal sinus fractures over a 9-year period was reviewed, and the fractures were classified into anterior wall, anterobasilar, and frontal skull fracture extensions. The presence of a concomitant CSF leak or an air-fluid level in the sinus was a diagnostic clue of posterior wall involvement. Ablation or obliteration of the fractured frontal sinus is not necessary. Primary reconstruction of the sinus and nasofrontal duct drainage constitute the preferred treatment. "Cranialization" of a severely damaged sinus is performed by excision of the posterior wall plugging of the nasofrontal duct and reconstruction of the anterior wall. Reconstruction of the anterior wall with primary bone grafting may be necessary in selected patients.     

Plantar soft tissue thickness during ground contact in walking.

A technique is introduced for the measurement of plantar soft tissue thickness during barefoot walking. Subjects stepped into an adjustable Plexiglas frame which ensured that the required bony landmarks were appropriately positioned relative to a linear ultrasound probe connected to a conventional 7.5 MHz ultrasound scanner. Clear images of the metatarsal condyles or other foot bones were obtained throughout ground contact. Subsequent analysis of the video taped images using a motion analysis system allowed the tissue displacement to be calculated as a function of time. The tissue underneath the second metatarsal head was shown to undergo an average maximum compression of 45.7% during the late stages of ground contact during first step gait in a group of five normal subjects with a mean unloaded tissue thickness of 15.2 mm. The technique has a number of applications, including use in the validation of deformation predicted by finite element models of the soft tissue of the foot, and the study of alterations in the cushioning properties of the heel by devices which constrain the displacement of the heel pad.     

The lateral osteotomy in rhinoplasty: clinical and radiographic rationale for osteotome selection

A preferred osteotome for endonasal osteotomy would facilitate reliable, complete osteotomies with minimal soft-tissue trauma. In this report, a radiographic evaluation of the bony lateral nasal wall thickness along the track of a high-low-high osteotomy was undertaken to guide the determination of appropriate osteotome size. Bone window axial computed tomographic scans were evaluated in 56 patients with a mean age of 48 years (range, 19 to 86 years). The average thickness along the site of lateral osteotomy was determined to be 2.47 mm (standard deviation, 0.47) in male patients and 2.29 mm (standard deviation, 0.40) in female patients. On the basis of these data, clinical evaluation of prototype 3- and 2.5-mm low-profile guarded osteotomes was undertaken in comparison with a "standard" 4-mm low-profile guarded osteotome to assess both their reliability and the degree of intranasal trauma, as reflected by intranasal mucosal tears. Although 2- and 3-mm unguarded osteotomes are time-tested, they may be reliable only in the hands of the most experienced surgeons. Therefore, a low-profile guard was included in the osteotome design to allow the surgeon to engage the bone securely and minimize the risk of slippage. Forty patients underwent rhinoplasty, for a total of 80 lateral osteotomies; the mean age of the patients was 38 (range, 16 to 75). In all cases, lateral osteotomies were accomplished with one pass. The 4-mm osteotome causes intranasal mucosal tears in 95 percent of osteotomies, the 3-mm osteotome in 34 percent, and the 2.5-mm in 4 percent. Early postoperative edema and ecchymosis were comparable among the groups. One patient, who underwent osteotomies with a 4-mm osteotome, had excessive postoperative narrowing, possibly due to his wearing of eyeglasses earlier than directed. This report suggests that proper selection of osteotome and attention to proper surgical technique results in a reliable, minimally traumatic lateral osteotomy through the endonasal approach. The 2.5-mm osteotome was reliable and the least traumatic to soft tissue of the osteotomes evaluated.     

Physiological Predetermination of the Order of Hardseededness Breakdown in Subterranean Clover (Trifolium subterraneum L.)

Hardseededness breakdown in the burr of subterranean clover(Trifolium subterraneum L.) was found to be non-random in occurrencewith respect to the relative position of seed in the burr. Thissuggests the presence of a predeterminative mechanism of theorder of hardseededness breakdown. While seed moisture content did not exhibit a pattern of variationconsistent with that for hardseededness breakdown, seed weightvariation appeared to conform closely with the pattern of breakdown. It is postulated that, either differences in seed size per sewithin the burr may determine the order of hardseededness breakdown,or that such differences may reflect a disproportionate supplyof translocate, and hence promotors or inhibitors, of hardseedednessbreakdown to the seeds of the burr. The implications of this finding to the assessment of genotypesfor differences in level of hardseededness level have been outlined.