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Objective: To clarify the clinical features of the microform cleft lip and to establish the ultrastructural characteristics of the orbicularis muscle., Design: Clinical observations of the characteristic deformities and associated anomalies were made. Muscle biopsies were harvested for histologic and ultrastructural analyses., Patients: Seventy-one consecutive patients with microform cleft lip were included in the study. Muscle biopsies were investigated in 11 patients among them., Results: Nasal deformity, a ridge or a groove from the vermilion to the nostril sill, and interruption of the "white roll" were present in all patients. Lack of a philtral column and a free border notch was observed in over 97% of patients. The orbicularis muscle demonstrated hypoplastic myofibers with nonneurogenic atrophy and focal accumulation of subsarcolemmal mitochondria., Conclusion: The typical gross morphology of the microform cleft lip is a surface manifestation of muscular defect, and the disruption of the muscle further extends down to the ultrastructural level. The clinical features, taken together with the ultrastructural defects of the musculature, might help with a more precise delineation of the microform cleft lip, and provide better understanding of cleft lip in general.

The aim of this study was to evaluate the immunohistochemical differences between the muscular fiber types in the pars peripheralis and pars marginalis of human orbicularis oris muscle. Five upper lips of fresh human adult cadavers were used. Full thickness of the upper lip, 5 mm in width, was harvested vertically at a peak point of cupid's bow. Troponin I-SS and Troponin I-FS antibodies were used to determinate the slow and fast skeletal muscle fibers. The pars peripheralis is composed of slow fibers (22%) and fast fibers (73%). The pars marginalis is composed of slow fibers (30%) and fast fibers (66%). We assume that the pars peripheralis and pars marginalis should be repaired sortably because the muscle reaction and endurance are not the same.

Muscular reconstructions in vertebrate paleontology have often relied heavily on the presence of "muscle scars" and similar osteological correlates of muscle attachment, a practice complicated by the fact that approximately half of tendinous muscle attachments to bone in extant vertebrates do not leave readily interpretable scars. Microanatomical and histological correlates of tendinous muscle attachment are much less ambiguous. This study examines the microanatomical correlates of muscle attachment for the mandibular adductors in six species of diapsids. Most prominent tendinous or aponeurotic muscle attachments display a high density of extrinsic fibers (similar to Sharpey's fibers). There is also some indication that the density of extrinsic fibers at an attachment may be directly related to the amount of stress exerted on that attachment. The presence of comparable densities of extrinsic fibers in fossil tissue constitutes strong and readily interpretable positive evidence for the presence of adjacent fibrous connective tissue in life. Microanatomy and histology provide reliable data about muscle attachments that cannot be gleaned from gross observation alone. These additional data, when coupled with existing muscular reconstruction techniques, may be essential to the resolution of ambiguous character states, and will provide more severe tests for long-standing hypotheses of musculature in extinct diapsids. Increasing the accuracy and precision of muscular reconstructions lends greater strength to any phylogenetic, paleobiological, or paleoecological inferences that draw upon these reconstructions as important lines of evidence., (Copyright 2006 Wiley-Liss, Inc.)

Aims: To compare the ultrastructural aspects of human extraocular muscles in two types of mitochondrial disease: chronic progressive external ophthalmoplegia (CPEO) and Leber's hereditary optic neuropathy (LHON)., Methods: Muscle samples of the medial rectus obtained from surgery in a sporadic case of CPEO associated with deleted mitochondrial DNA, and post mortem in a case of 3460/ND1 LHON were processed for electron microscopy (EM). The medial rectus from an autoptic time to fixation matched control was used to exclude postmortem artefacts., Results: The CPEO specimen revealed focal areas of disruption and abnormalities of mitochondria in some muscle fibres, creating a "mosaic-like" pattern. In the LHON specimen a diffuse increase in both number and size of mitochondria (mean diameter 0.85 mum v 0.65 mum of control, p<0.0001) with swollen appearance and disorganised cristae filled all spaces of sarcoplasmic reticulum. In some areas the excessive number of mitochondria slightly distorted myofibrils., Conclusion: EM investigation of extraocular muscles in CPEO and LHON reveals marked differences. A "mosaic-like" pattern caused by a selective damage of muscle fibres was evident in CPEO, whereas a diffuse increase in mitochondria with preservation of myofibrils characterised the LHON case. These ultrastructural changes may relate to the different expression of the two diseases, resulting in ophthalmoplegia in CPEO and normal eye movements in LHON.

Aims: In order to evaluate the pathogenesis of cleft-lip in relation to both the anatomical and structural anomalies of the mesenchymal tissues, the authors concluded that the presence of structural anomalies in the examined tissues could not explain the malformation, but might be a consequence of it. Delayed muscular development, asymmetrical distribution of the muscular fibres and their anomalous insertion suggest that the anatomical/functional loss clinically detectable in the orbicular muscle could be the result of a perinatal dysmorphological process rather than of a simple mesenchymal hypoplasia., Methods: Schendel et al. suggested that a metabolic defect in the mitochondrial function could cause a deficiency in cell migration and proliferation responsible for the malformation in question. To establish whether the pathogenesis of the cleft-lip is associated with an alteration in mitochondrial functionality, eight patients affected by unilateral cleft-lip were subjected to a biopsy of the orbicular muscle during the course of reparative surgery., Results: The results obtained showed: 1) a great variation in the size of muscle fibres; 2) the absence of ragged red fibres; 3) a normal oxidative function in the muscle fibres examined; 4) the absence of typologically significant groupings positive for myofibral ATPases. Furthermore, the morphology of the mitochondria was preserved in all cases and neither inclusions nor morphological or volumetric changes were detected., Conclusions: This preliminary data did not confirm the constant presence of mitochondrial pathology responsible for the malformation in question. In our opinion, the growth deficiency of the maxillary segment could be ascribed to the cicatrization of the surgical repair of the cleft-lip.

A study was undertaken to determine the physical properties and microscopic structure of the superficial musculoaponeurotic system (SMAS) tissue. Forty virginal specimens and eight reoperated specimens were examined. The following findings were discovered. 1) Microscopic appearance shows the SMAS to consist of collagen fibers, a relatively high concentration of elastic fibers interspersed with fat cells. 2) On scanning electron microscopy, the virginal SMAS shows the collagen fibers to have a similar convoluted appearance as in the dermis. There is some evidence of parallelization of the collagen fibers in the reexcised SMAS specimens. 3) Mechanical testing (Instron) demonstrates that both the SMAS and preauricular skin were subjected to a series of loading/ unloading tests at various rates, amplitudes, and stress relaxation tests. Both sets of specimens indicated definite viscoelastic properties. Although the mechanical behavior of both tissues was somewhat similar, the viscoelastic effect of the SMAS was less pronounced. A slackening effect of the SMAS indicated a gradual expansion of the SMAS postoperatively. These results could provide some indication of the long-term effects of SMAS surgery.

Model 7.62 mm, model 5.56 mm bullets and 1.03 g steel sphere, 1.0 g fragment with impacting velocities 1300-1400 m/s were used to shot soap target, mandibular area of pigs in vitro and dogs in vivo. The shape and size of cavitations and wounds were observed and the specimens of wounded muscles were collected for light and electron microscopic observation. The authors found that different kinds of cavitations formed in different kinds of projectiles wound, which produced different injured characteristics in maxillofacial firearms wound. The characteristics of maxillofacial wound ballistics and difference of maxillofacial wounds in different kinds of high velocity projectiles wound were also discussed in the article.

Immunohistochemistry was used to determine the myosin composition of defined fibre types of three embryologically different adult muscles, the oro-facial, masseter and limb muscles. In addition, the myosin composition in whole muscle specimens was analysed with biochemical methods. Both similarities and differences between muscles in the content of myosin heavy chains and myosin light chains were found. Nevertheless, each muscle had its own distinct identity. Our results indicated the presence of a previously undetected fast myosin heavy chain isoform in the oro-facial type II fibre population, tentatively termed 'fast F'. The masseter contained aberrant myosin isoforms, such as foetal myosin heavy chain and alpha-cardiac myosin heavy chain and unique combinations of myosin heavy chain isoforms which were not found in the limb or oro-facial muscles. The type IM and IIC fibres coexpressed slow and fast A myosin heavy chains in the oro-facial and limb muscles but slow and a fast B like myosin heavy chain in the masseter. While single oro-facial and limb muscle fibres contained one or two myosin heavy chain types, single masseter fibres coexpressed up to four different myosin heavy chain isoforms. Describing the fibres according to their expression of myosin heavy chain isozymes, up to five fibre types could be distinguished in the oro-facial and limb muscles and eight in the masseter. Oro-facial and limb muscles expressed five myosin light chains, MLC1S, MLC2S, MLC1F, MLC2F and MLC3F, and the masseter four, MLC1S, MLC2S, MLC1F, and, in addition, an embryonic myosin light chain, MLC1emb, which is usually not present in normal adult skeletal muscle. These results probably reflect the way the muscles have evolved to meet the specialized functional requirements imposed upon them and are in agreement with the previously proposed concept that jaw and limb muscles belong to two distinct allotypes.

This study provides a comparative characterization of four human oro-facial muscles, one masticatory muscle (the masseter) and two limb muscles, with respect to muscle fibre types, myosin isoforms and capillary supply. Enzyme-histochemical methods were used to evaluate the myofibrillar ATPase fibre type composition. Immuno-histochemical techniques were used to determine the expression of myosin heavy chain (MHC) isoforms in the different fibre types. The contents of MHCs and myosin light chains (MLC) in different muscles were analysed with electrophoretic methods. In addition, the capillary bed of the muscles was evaluated using both enzyme- and immuno-histochemical techniques. The fibre type compositions of the oro-facial and masseter muscles were found to be qualitatively and quantitatively different from each other and from those of limb muscles. In general, the oro-facial muscles contained a predominance of unusually high oxidative type II fibres, with a staining reaction for ATPase in between that of type IIA and type IIB fibres, termed type IIAB. In fact, one of the oro-facial muscles, the zygomatic minor, showed the highest type II fibre proportion ever reported in humans. This fibre type pattern is in contrast to that of the masseter muscle, which contains a majority of type I fibres, small diameter low oxidative type IIB fibres and a significant proportion of ATPase-intermediately stained fibres, termed IM, and IIC. Inter- and intra-muscular variability in fibre size and shape was considerable in both the oro-facial and masseter muscles. The oro-facial muscles were devoid of muscle spindles. The immuno-histochemical and biochemical analyses showed a characteristic myosin composition of each muscle. Notably, the results indicated the presence of a previously undetected fast MHC isoform in the oro-facial muscles, tentatively termed "fast F". The masseter contained unusual myosin isoforms, such as fetal and alpha-cardiac MHCs, and unique combinations of MHC isoforms which were not found in the limb or oro-facial muscles. The type IM and IIC fibres co-expressed slow and fast A MHCs in the oro-facial and limb muscles, but slow and a "fast B like" MHC in the masseter. Individual fibres in the oro-facial and limb muscles contained one or two MHC isoforms, whereas individual fibres in the masseter co-expressed up to four different MHC isoforms. On the basis of their pattern of expression of MHC isoforms, up to five fibre types could be distinguished in the oro-facial and limb muscles and eight in the masseter.(ABSTRACT TRUNCATED AT 400 WORDS)

The migration of facial motoneurons is affected by the reeler gene, and the facial nucleus of the reeler mutant is cytoarchitecturally abnormal. The present study was undertaken to compare the musculotopic organization of the reeler facial nucleus with that of the normal mouse by the retrograde horseradish peroxidase method. In the normal mouse, motoneurons supplying the nasolabial muscle were located in the lateral and dorsolateral subnuclei, those supplying the posterior auricular muscle in the ventromedial and dorsomedial subnuclei, those supplying the mentalis/platysma muscle in the ventral intermediate subnucleus of the facial nucleus, and those supplying the posterior belly of the digastric muscle in the accessory facial nucleus. This musculotopic representation on the main facial nucleus and accessory facial nucleus also appears in the reeler mouse. The musculotopic representation of the facial nucleus of the reeler mouse is thus identical to that of the normal mouse in spite of the former's cytoarchitectonic abnormalities.

Congenital ptosis with poor levator function is now managed by frontalis suspension techniques. While this procedure is better than those used in the past, serious shortcomings exist. A technique producing more normal lid function would be a beneficial addition to surgical management. Since congenital ptosis is thought to be a focal myopathy, we investigated the potential of myoblast transfer therapy in myopathic levator palpebrae superioris. Satellite cells harvested from temporalis muscle were grown as clones, labeled with Dil, and transplanted into experimentally myopathic levator muscle of the same animal. Within 2 weeks, the injected cells were found to be incorporated into muscle fibers within the levator basal lamina. The control side appeared myopathic with very little muscle regeneration. The presence of Dil labeled muscle fibers in the experimental muscles strongly suggests their origin from the injected cells. Electron microscopy of nearby sections showed these fibers to be maturing striated muscle. We feel that the development of this technique may make autogenous myoblast transfer therapy a useful treatment for congenital ptosis and other focal myopathies.

The known difference in the severity of dystrophy between the masseter and the digastric muscle of the mouse (dy/dy C57BL/J6) may be attributed to the differences in muscle work load. This possibility was tested by subjecting 3-week-old mice (normal and dystrophic) to a soft diet for 4 weeks. Microscopic examination of haematoxylin-eosin stained sections of these muscles showed that the fibre size dispersion (a measure of disease severity) decreased slightly but significantly in the masseters of mice on a soft diet. It was thus possible to improve the condition of dystrophic masticatory muscles by changing their function. Body weight curves measured during the experimental period suggest that the dystrophic mice may have been under weight because of malnutrition due to lack of sufficient masticatory power.

Capillaries in the retina and rectus muscles of vitamin E and selenium deficient rats were examined by electron microscopy. In vitamin E deficient rats, retinal capillaries showed thickening of the basement membranes of the endothelial cells. On the other hand, capillaries in the muscles had thin basement membranes, and hemorrhages occurred due to the breakdown of endothelial cells. In selenium-deficient rats no significant abnormalities were seen in retinal or muscle capillaries. Although selenium has been considered to be similar to vitamin E as an antioxidant, the present study suggests that they are different. The effect of vitamin E on capillary basement membranes varies from tissue to tissue.

In 8 patients with chronic progressive ocular muscular dystrophy, of whom some showed a weakness of lid closure, and in 3 normal persons (aged 62 to 69 years) biopsies of the orbicularis oculi muscle were investigated with the light- and electron microscopes. We tried to find out if the histopathological investigation alone of the orbicularis oculi muscle can establish the diagnosis of ocular muscular dystrophy or not. Both groups of investigated persons showed myopathic changes in the orbicularis oculi muscle. These changes were explained as followings of catabiosis (so called "secondary myopathic reaction") in the normal persons. The changes of the patients with myopathies, however, were explained as primarily myopathic, especially with regard to the anomalies of structure, and the pathological inclusions of the mitochondria. The findings showed that there occurred similar histopathological phenomena seen by light microscope in both groups of investigated persons; the muscle cell changes of the myopathy patients, however, were more prominent in the examination of the ultrastructure.

The ultrastructure of normal human facial muscles from 25 nonparalytic and 17 paralytic patients revealed normal features in nondenervated human facial muscles, identical to the fine structure of other normal human and mammalian cross-striated muscle fibers. However, in denervated facial muscle, a broad spectrum of ultrastructural lesions had affected sarcomeres, abnormal inclusions, and organelles. A large variety of inclusion bodies, some of which have not been described, were also found. The spectrum of ultrastructural changes showed no dependence on the length of the denervation period. There were no inclusion bodies in all the normal facial muscle biopsies. To our knowledge, this study represents the first systematic electron microscopic investigation of normal and denervated human facial muscles.

The authors examined electron microscopically the daily effects of the muscle spindles of the mole snout muscles following unilateral facial neurotomy. The denervated muscle spindles show first a degenerative sign of the sensory end bulb 1 day after the operation and later a degenerative sign of the intrafusal muscle fibers one week after the operation. The muscle spindles on the untreated side show first a degenerative sign of the intrafusal muscle fibers 2 weeks after the operation and later a degenerative sign of the sensory end bulb 20 days after the operation. 40 to 90 days after the operation, the spindles on both sides show the same degenerative signs, the intrafusal muscle fibers having become much thinner than the control.

A case of proliferative myositis of the buccinator muscle is reported. To our knowledge, the present case is the second reported in the oromaxillary region. From immunohistochemical and electron microscopic studies, it seems likely that the ganglion-like cells are derived from myofibroblasts or macrophages rather than from striated muscle cells.

At light optic and electron microscopical levels with application of morphometric analysis the mouth orbicular muscle has been studied in 6-8-month-old children with a complete unilateral cleft lip. The muscle is characterized by distinctly manifested signs of hypertrophy: high contents of the connective tissue, poor capillarization, presence of focal destructive-degenerative changes in the muscle fibers; they result from decreased function of the muscle activity. Preoperative physiotherapeutic treatment with pulsed low-frequency electrical current stimulates development of the muscle tissue. In the muscle specific share of muscle fibers increases, and contents of the connective tissue decreases, respectively, indices of capillarization improve, mitochondrial apparatus of the muscle fibers becomes more powerful.

The medial rectus, external rectus and inferior oblique muscles were examined by electron microscopy in Möbius syndrome. The electron microscopic findings of the medial rectus and inferior oblique were of degenerative and inflammatory nature, whereas the lateral rectus showed complete fibrosis. The fibrotic lateral rectus could explain the absence of abduction in Möbius syndrome.

The author reports on the advantages of Fox's technique in the surgery of senile entropion on the basis of experiences with 30 interventions on 26 patients. In the evolution of senile entropion the structural changes in the orbicularis oculi muscle plays a decisive role, which leads to the malfunction of the muscle. The degenerative changes of the muscle are shown with electron microscopy. The author recommends the Fox technique because this type of intervention aims to abolish the cause of the aging process and not only the consequences of it as other methods do.

Fifty-five cases of senile entropion and ectropion have been studied electron microscopically. In both senile entropion and ectropion significant ultrastructural abnormalities were found in the orbicular muscle fibres, such as a disruption of fibres, Z line streaming, rod formation, Z line duplication and cytoplasmic body formation. These alterations have been described only in neuromuscular disorders and systemic diseases affecting the skeletal muscles. Our observations have confirmed that these abnormalities are not specific signs of any given disease, they rather represent the ultrastructural background of impaired muscle function independently of the aetiology of the disease.

Muscle changes were investigated ultrastructurally in 2 groups of patients having oral submucous fibrosis. One group was from patients with no evidence of restricted mouth opening and the other was from patients with restricted mouth opening. Electronmicroscopically, the majority of muscle fibres taken from the first group appeared normal with only occasional muscle fibres showing accumulation of homogeneous material and compression of the sarcomeres closest to this material. In contrast, the tissues from patients with restricted mouth opening showed severe changes and necrosis in a high proportion of muscle fibres. The necrotic muscle fibres exhibited complete loss of their plasma membrane, but in which the outline was maintained by an intact basal lamina. It is suggested from this study that restricted mouth opening in submucous fibrosis might depend not only on the subepithelial fibrosis but also on the extent of muscle degeneration.