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Duke University Longitudinal Studies of Aging.

The Duke Longitudinal Studies of Aging were preceded by a research project supported by the National Institutes of Health and entitled "The Effects of Aging upon the Central Nervous System: A Physiological and Psychological Approach." These earlier studies formed a solid basis for designing and carrying out the two Duke Longitudinal Studies. The Duke longitudinal interdisciplinary research team existed between 1955 and 1980. The first longitudinal study of "normal aging" began in 1955. The subjects were 270 community residents and volunteers aged 60 to 90. Eleven rounds of complete examinations were carried out. The eleventh and final round occurred in 1976. The second Duke Longitudinal Study (also known as the "Adaptation Study") began in 1968 and ended in 1976. The research design was cross-sequential with 502 subjects 46 to 70 years of age. Numerous ancillary studies were conducted on both studies. Both studies included biomedical, psychological, and socioeconomic observations and evaluation procedures. All data are preserved and available for secondary analysis by qualified persons.

Adaptation, Psychological↗
PubMed1990

Transverse or longitudinal arteriotomies in end-to-side microvascular anastomoses for small vessels (1-2 mm).

This investigation quantitatively compared lumenal dimensions of 1 mm end-to-side anastomoses with longitudinal or transverse arteriotomies into host arteries 1.5-2 mm in diameter. In 27 rats, 6-7 mm sections of iliac arteries (1 mm in diameter) were sutured as small bypasses onto abdominal aortae (1.5-2 mm in diameter). Half the anastomoses were performed on transverse. and half on longitudinal arteriotomies. Between 1 and 20 weeks following surgery intravascular methacrylate casts were made of the aortae and bypasses, and detailed measurements taken from the casts. The success rate (patency) of the bypasses was 78%; 18 successful casts (36 anastomotic sites) were analysed; 6 failed due to stenosis (3 other successful bypasses were used to develop the techniques). From these, five sites developed small dilations ("aneurysms"), which did not occur preferentially on either longitudinal or transverse arteriotomy sites. Despite a trend towards a greater diameter in the transverse compared with the longitudinal arteriotomies, they were not statistically different. Therefore, the authors recommend for technical reasons that for small end-to-side vascular anastomoses the transverse arteriotomy is preferable: it produces a simple incision which opens the artery and facilitates suturing. With a longitudinal arteriotomy in such small vessels it is often necessary to remove an elliptical area of tissue, which may produce an excessive defect.

Anastomosis, Surgical↗
PubMed1994

Hallux valgus, first metatarsal pronation and collapse of the medial longitudinal arch--a radiological correlation.

In a previous study we developed a model to assess first metatarsal pronation based on the position of the inferior tuberosity of its base and showed a significant relationship between first metatarsal pronation and the intermetatarsal angle (r = 0.69, p < 0.001). The present study was undertaken to correlate first metatarsal pronation with the height of the medial longitudinal arch in an attempt to define the clinical significance of this new finding. The weight-bearing anteroposterior and lateral radiographs of the feet of 50 patients (100 feet; 36 females patients of mean age 38 years, 14 males patients of mean age 40 years) were reviewed, and in each case, the patient's age, sex, intermetatarsal angle, amount of first metatarsal pronation and medial longitudinal arch angle were recorded by independent observers. A significant relationship was demonstrated between first metatarsal pronation and the height of the medial longitudinal arch (r = 0.93, p < 0.0001). Less marked association was observed between intermetatarsal angles and first metatarsal pronation (r = 0.71, p < 0.001). Multivariate analysis of patient age, sex, intermetatarsal angle and medial longitudinal arch angle against metatarsal pronation showed that the single most dominant variable affecting metatarsal pronation was the height of the medial longitudinal arch.

Adult↗
PubMed2001

Changes in the Epilimnetic Bacterial Community Composition, Production, and Protist-Induced Mortality along the Longitudinal Axis of a Highly Eutrophic Reservoir.

We studied changes in the epilimnetic bacterial community composition (BCC), bacterial biomass and production, and protistan succession and bacterivory along the longitudinal axis of the canyon-shaped, highly eutrophic Sau Reservoir (NE Spain) during two sampling campaigns, in April and July 1997. Longitudinal changes in BCC from the river inflow to the dam area of the reservoir were detected by using oligonucleotide probes targeted to the kingdom Bacteria, to the alpha, beta, and gamma subclasses (ALFA, BETA, and GAMA) of the class Proteobacteria, and to the Cytophaga/Flavobacterium (CF) cluster. In general, the inflow of the organically loaded Ter river, with highly abundant allochthonous bacterial populations, induced a clearly distinguishable longitudinal succession of the structure of the microbial food web. The most dynamic changes in microbial parameters occurred at the plunge point, the mixing area of river water and the reservoir epilimnion. Changes within members of BETA and CF were the most important in determining changes in BCC, bacterial abundance and biomass. Much less relevant changes occurred within the less abundant ALFA and GAMA bacteria. From the plunge point downstream, we described a significant shift in BCC in the form of decreased proportions of BETA and CF. This shift spatially coincided with the highest values of heterotrophic nanoflagellate bacterivory (roughly doubled the bacterial production). CF numerically dominated throughout the reservoir without any marked longitudinal changes in their mean cell volume. In contrast, very large cells affiliated to BETA clearly dominated in the allochthonous bacterial biomass brought by the river. BETA showed a marked downstream trend of decreasing mean cell volume. We conclude that the observed BCC shift and the longitudinal shift in food web structure (bacteria-heterotrophic nanoflagellates-ciliates) resulted from highly complex interactions brought about by several major factors: varying hydrology, the high localized allochthonous input of organic matter brought by the river, downstream changing substrate availability, and selective protistan bacterivory.

Journal Article↗
PubMed2002

Primary longitudinal adhesion structures: plectin-containing precursors of costameres in differentiating human skeletal muscle cells.

Plectin is a high molecular mass protein (ca 530 kDa) that binds actin, intermediate filaments, and microtubules. Mutations of the human plectin gene cause epidermolysis bullosa simplex with muscular dystrophy. In mature human skeletal muscle, plectin is localized between neighboring myofibrils and between myofibrils and the sarcolemma, both at the level of Z-discs. In the present study we have analyzed plectin expression patterns with emphasis on its sarcolemmal localization during human skeletal muscle differentiation in vitro. In myoblasts plectin showed a cytoplasmic intermediate filament-like distribution, whereas in myotubes plectin is also found at the level of the sarcolemma. In particular, in early myotubes a specific plectin isoform colocalizes with the costameric proteins vinculin and beta1D integrin in longitudinally orientated structures which increased in number and longitudinal extension upon further maturation. In mature myotubes processes perpendicular to the parallel system of longitudinal structures became apparent. Subsequent to the occurrence of spontaneous myofibrillar contractions, the number of longitudinal streaks decreased, and plectin and other costameric proteins were found in an orderly cross-striated sarcolemmal lattice overlying myofibrillar Z-discs. Our study demonstrates that plectin is preassembled together with vinculin and beta1D integrin into primary longitudinal adhesion structures. After the occurrence of spontaneous contractions, these structures reorient and mature costameres are assembled.

Cell Differentiation↗
PubMed1981

Effects of catecholamines on circular and longitudinal uterine muscle of the rat.

Responses of circular and longitudinal myometrial strips to norepinephrine and isoproterenol were compared in pregnant and non-pregnant rats. Norepinephrine stimulated spontaneous contractions in circular muscle and inhibited contractions in longitudinal muscle from mid-pregnancy until term. The sensitivity of circular muscle to norepinephrine declined over this period and at term norepinephrine 10(-6) M inhibited contractions. Isoproterenol inhibited contractions in both circular and longitudinal muscles during pregnancy. The sensitivity of circular muscle to isoproterenol increases at term but did not change in the longitudinal muscle. The effects of norepinephrine in circular muscle were not duplicated by treatment of non-pregnant rats with ovarian steroids. The results imply a relative dominance of alpha-adrenoceptors in circular muscle and beta-receptors in longitudinal muscle during pregnancy. The reversal of the effects of norepinephrine at term in the circular muscle is related to an increase in sensitivity and/or number of beta-receptors in this muscle.

Animals↗
PubMed1981

Evidence that the action of cholecystokinin octapeptide on the guinea pig ileum longitudinal muscle is mediated in part by substance P release from the myenteric plexus.

Studies were made on the mode of action of cholecystokinin octapeptide (CCK8) on longitudinal muscle strips of guinea pig ileum in vitro. CCK8 produced dose-related contractions of innervated strips of ileum longitudinal muscle (EC50 3--4 x 10(-9) M), but was inactive on denervated strips. Tetrodotoxin, and reducing the bath temperature to 15 degree C, abolished the response of innervated strips to CCK8. These results indicate that the action of CCK8 on ileal longitudinal muscle is mediated by the myenteric plexus. Atropine abolished the responses to acetylcholine and to low doses of CCK8. However, the responses to CCK8 in doses above 10(-8) M were reduced by atropine but not abolished. Incubation of longitudinal muscle strips with high concentrations of substance P (1.5 x 10(-7) M) resulted in desensitization to this peptide; this treatment inhibited the responses to CCK8 alone, and abolished the atropine-resistant actions of CCK8. Desensitization to substance P had no effect on the responses to acetylcholine, histamine, serotonin and angiotensin II. The results indicate that CCK8 contracts the longitudinal muscle of guinea pig ileum by releasing acetylcholine and substance P from the myenteric plexus.

Acetylcholine↗
PubMed1992

Identification of motor neurons to the longitudinal muscle of the guinea pig ileum.

Motor neurons that innervate the longitudinal muscle of the guinea pig ileum were identified by retrograde transport from the longitudinal muscle plexus in organotypic culture. Motor neurons had short projections, less than 3.5 mm long, and never had Dogiel type II morphology; most labeled neurons had morphological characteristics of Dogiel type I neurons. Immunoreactivity for choline acetyltransferase was present in 97% of retrogradely labeled nerve cell bodies, reflecting the dominant cholinergic input to the longitudinal muscle layer. Substance P immunoreactivity was present in 48% of motor neurons, indicating that it or a similar tachykinin that mediates noncholinergic excitatory transmission is likely to be released by a subset of cholinergic motor neurons. This strongly suggests that the difference in frequency dependence of substance P and acetylcholine release is attributable to different release mechanisms rather than to activation of separate populations of motor neurons. Immunoreactivity for the calcium-binding protein calretinin was present in 87% of longitudinal muscle motor neurons. The neurochemical coding of longitudinal muscle motor neurons indicated that they constitute about one quarter of all myenteric neurons and are distinct from circular muscle motor neurons.

Animals↗
PubMed1982

Left ventricular work and power: circumferential, radial and longitudinal components. Mathematical derivation and characteristic variation with left ventricular dysfunction.

Cardiac work and power, defined as the wall stress-velocity product per unit volume, have been derived with respect to a circumferential, radial and longitudinal component for the human left ventricle during a complete cardiac cycle. Thirty-nine patients, comprising five clinical groups, were evaluated using pressure and volume data acquired from single-plane cineangiography. The results indicate that work and power are divided into approximately 60% circumferential, 23% radial and 17% longitudinal components for normals. Characteristic variations from normal are presented for selected pathological case studies. With a compensated volume overload patient, diastolic work and power are uniformly reduced in all three directions and systolic radial power approximately equals longitudinal power. With a decompensated volume overload patient, systolic radial power is greater than longitudinal power. With a compensated pressure overload patient, systolic radial work and power are greatly elevated as compared to the normals and represent about 30% of the total work and power, while longitudinal work and power represent only about 8% of the total. With a congestive cardiomyopathy patient, systolic work and power are greatly reduced in all three directions as compared to normals.

Adult↗
PubMed1982

Effects of PGD2 and PGF2 alpha on longitudinal and circular muscles of guinea-pig isolated proximal colon.

The mechanical effects of PGD2 and PGF2 alpha on longitudinal and circular muscles of the guinea-pig isolated proximal colon were investigated. PGD2 and PGF2 alpha (1 nM - 10 microM) produced a dose-dependent contraction in longitudinal and circular muscles. The contractile action of PGD2 was more potent than that of PGF2 alpha in circular muscle and was less potent in longitudinal muscle. Contractions induced by PGD2 or PGF2 alpha (1 microM) were unaffected by atropine(1 microM) in both muscles, but tetrodotoxin(1 microM) slightly inhibited these contractions in longitudinal muscle. The results suggest that in longitudinal muscle PGD2 and PGF2 alpha have largely a direct action on the muscle cells and a partial neuronal action on the non-cholinergic intrinsic nerves, whereas in circular muscle these PGs have only a direct action on the muscle cells.

Acetylcholine↗
PubMed1996

Biomechanics of longitudinal arch support mechanisms in foot orthoses and their effect on plantar aponeurosis strain.

OBJECTIVE: The purpose of this investigation was to quantify the longitudinal arch support properties of several types of foot orthosis. DESIGN: An in vitro method that simulated 'static stance' was used to determine arch support capabilities, with plantar aponeurosis strain implemented as the performance measure. BACKGROUND: A longitudinal arch support mechanism of an orthosis resists depression of the foot's arches by transferring a portion of the load to the medial structures of the foot. Since the plantar aponeurosis is in tension when the foot is loaded, a quantifiable decrease in strain should occur with an adequate orthotic arch control mechanism. METHODS: A differential variable reluctance transducer was surgically implanted in the plantar aponeurosis of cadaveric donor limb feet (n = 7). Each specimen was mounted in an electromechanical test machine which applied a load of up to 900 N axially to the tibia. The test schedule was divided into seven test conditions: specimen barefoot; specimen with shoe and specimen with shoe and five different orthoses. RESULTS: The University of California Biomechanics Laboratory Shoe Insert and two other foot orthoses significantly decreased the strain in the plantar aponeurosis compared to the barefoot control and were considered effective arch supports (P < 0.05). The functional foot orthosis, stock orthosis, and test shoe did not effectively reduce plantar aponeurosis strain. Significant variations of time required to achieve the specified load levels were recorded among the test conditions, indicating the relative cushioning properties of the shoe/orthosis systems. CONCLUSIONS: The patterns of plantar aponeurosis strain observed in cadaveric tests suggest that certain types of orthoses are more effective than others in the support of the foot's longitudinal arches. It is suggested that to support the longitudinal arches of the foot effectively the medial surface contours of the orthosis must stabilize the apical bony structure of the foot's arch. RELEVANCE: Reducing tension in the plantar aponeurosis is an important treatment objective for orthotic management of plantar fasciitis. Therefore it is of great clinical interest to know whether the longitudinal arch support mechanism of specific foot orthoses have benefits with respect to the loading of the plantar aponeurosis.

Journal Article↗
PubMed1993

Involvement of nitric oxide pathway in non-adrenergic non-cholinergic (NANC) relaxation in the rat stomach: differential innervation of NANC nerves in the longitudinal and circular muscle of the fundus.

1. The effects of NG-nitro-L-arginine (L-NNA) on non-adrenergic, non-cholinergic (NANC) relaxation elicited by transmural nerve stimulation (TNS) or high K+ were studied in the rat stomach fundus in order to investigate the mode of innervation of NANC nerves in the longitudinal and the circular muscle of the fundus. 2. Relaxation responses of the fundus to TNS were larger in circular than in longitudinal muscle strips. 3. Treatment with L-NNA (10(-5) M) reduced slightly but significantly the relaxation induced by TNS in both circular and longitudinal muscle strips of the fundus. The inhibitions of the TNS-induced relaxation by L-NNA were reversed partly by L-arginine (10(-3) M). 4. Although K+ produced concentration-dependent contraction in longitudinal muscle strips of the fundus, low concentration of K+ (20 mM) produced rapid and long-lasting relaxation in circular muscle strips of the fundus. 5. The 20 mM of K(+)-induced relaxation in circular muscle strips was significantly inhibited by L-NNA (10(-5) M) or oxyhemoglobin (2 x 10(-5) M). The inhibition of the K+ (20 mM)-induced relaxation by L-NNA was reversed by L-arginine (10(-3) M). 6. These results suggest that NO is one of mediators or transmitters in the NANC relaxation of the rat fundus, and that the density of NO-containing NANC nerves in the stomach fundus is richer in circular than in longitudinal muscle.

Animals↗
PubMed2006

Abnormal longitudinal myocardial functional reserve assessed by exercise tissue Doppler echocardiography in patients with hypertrophic cardiomyopathy.

BACKGROUND: Previous studies have shown that mitral annular velocities are reduced in patients with hypertrophic cardiomyopathy (HCM). However, the response of systolic and diastolic velocities of the mitral annulus to exercise in patients with HCM has not been explored previously. Because pathologic left ventricular (LV) hypertrophy is associated with myocardial fibrosis, particularly in the subendocardium, we hypothesized that mitral annular systolic and diastolic velocities during exercise and at rest would be abnormal in patients with HCM. METHODS: Mitral septal annular systolic (S') and early diastolic (E') velocities were measured at rest and during graded supine bicycle exercise (25 W, 3-minute increments) in 40 patients with HCM (29 male, mean age 56 years) and 41 age- and sex-matched control subjects. LV diastolic and systolic longitudinal function reserve index were calculated using a new formula. RESULTS: There were no significant differences in mitral inflow velocities (early mitral filling velocity [E], E/A, deceleration time of E velocity [DT]) at rest between the two groups except late mitral filling (A) velocity, which was higher in control group. Increase in E' with exercise was significantly smaller in patients with HCM compared with control subjects (1.7 +/- 1.3 vs 3.4 +/- 2.5 cm/s from base to 25 W, P = .0006; 2.2 +/- 1.9 vs 4.5 +/- 2.8 cm/s from base to 50 W, P = .0002). Although LV ejection fraction at rest was significantly higher in patients with HCM compared with that of control subjects (71 +/- 7 vs 66 +/- 7, P = .0019), S' at rest (6.0 +/- 1.2 vs 6.8 +/- 1.1 cm/s, P = .011) was significantly lower in patients with HCM. Although a significant increase in S' was detected with exercise in control subjects, increase in S' with exercise was blunted in patients with HCM (6.4 +/- 1.4 vs 8.5 +/- 2.5 cm/s at 25 W, P = .0004; 7.0 +/- 1.4 vs 9.5 +/- 2.4 cm/s at 50 W, P < .0001). Longitudinal systolic (0.37 +/- 0.85 vs 1.47 +/- 1.75 cm/s at 25 W, P = .0034; 0.79 +/- 1.08 vs 2.32 +/- 1.66 cm/s at 50 W, P = .0001) and diastolic (1.29 +/- 1.06 vs 2.84 +/- 2.12 cm/s at 25 W, P = .0002; 1.63 +/- 1.46 vs 3.77 +/- 2.31 cm/s at 50 W, P < .0001) function reserve index was significantly lower in patients with HCM compared with that of control subjects. CONCLUSION: Augmentation of LV longitudinal function during exercise is blunted in patients with HCM, suggesting longitudinal functional reserve and resting longitudinal function is abnormal in these patients.

Cardiomyopathy, Hypertrophic↗
PubMed2005

Study on the Langevin piezoelectric ceramic ultrasonic transducer of longitudinal-flexural composite vibrational mode.

In this paper, the Langevin longitudinal-flexural composite mode piezoelectric ultrasonic transducer is studied. This type of transducers consists of slender metal rods and longitudinally polarized piezoelectric ceramic rings. The resonance frequency equations for the longitudinal and flexural vibrations in the transducer are derived. By correcting the length of the metal slender rods, the simultaneous resonance of the longitudinal and flexural vibrations in the transducer is acquired. The experimental results show that the measured resonance frequencies of the transducers are in good agreement with the computed ones, and the measured resonance frequencies of the longitudinal and the flexural vibrations in the composite transducers are also in good agreement with each other.

Journal Article↗
PubMed2006

Longitudinal and shear mode ultrasound propagation in human skull bone.

Recent studies have attempted to dispel the idea of the longitudinal mode being the only significant mode of ultrasound energy transport through the skull bone. The inclusion of shear waves in propagation models has been largely ignored because of an assumption that shear mode conversions from the skull interfaces to the surrounding media rendered the resulting acoustic field insignificant in amplitude and overly distorted. Experimental investigations with isotropic phantom materials and ex vivo human skulls demonstrated that, in certain cases, a shear mode propagation scenario not only can be less distorted, but at times allowed for a substantial (as much as 36% of the longitudinal pressure amplitude) transmission of energy. The phase speed of 1.0-MHz shear mode propagation through ex vivo human skull specimens has been measured to be nearly half of that of the longitudinal mode (shear sound speed = 1500 +/- 140 m/s, longitudinal sound speed = 2820 +/- 40 m/s), demonstrating that a closer match in impedance can be achieved between the skull and surrounding soft tissues with shear mode transmission. By comparing propagation model results with measurements of transcranial ultrasound transmission obtained by a radiation force method, the attenuation coefficient for the longitudinal mode of propagation was determined to between 14 Np/m and 70 Np/m for the frequency range studied, while the same for shear waves was found to be between 94 Np/m and 213 Np/m. This study was performed within the frequency range of 0.2 to 0.9 MHz.

Acoustics↗
PubMed2004

Longitudinal diffusion in retinal rod and cone outer segment cytoplasm: the consequence of cell structure.

Excitation signals spread along photoreceptor outer segments away from the site of photon capture because of longitudinal diffusion of cGMP, a cytoplasmic second messenger. The quantitative features of longitudinal diffusion reflect the anatomical structure of the outer segment, known to be profoundly different in rod and cone photoreceptors. To explore how structural differences affect cytoplasmic diffusion and to assess whether longitudinal diffusion may contribute to the difference in signal transduction between photoreceptor types, we investigated, both theoretically and experimentally, the longitudinal diffusion of small, hydrophilic molecules in outer segments. We developed a new theoretical analysis to explicitly compute the longitudinal diffusion constant, Dl, in terms of outer segment structure. Using time-resolved fluorescence imaging we measured Dl of Alexa488 and lucifer yellow in intact, single cones and validated the theoretical analysis. We used numerical simulations of the theoretical model to investigate cGMP diffusion in outer segments of various species. At a given time interval, cGMP spreads further in rod than in cone outer segments of the same dimensions. Across all species, the spatial spread of cGMP at the peak of the dim light photocurrent is 3-5 microm in rod outer segments, regardless of their absolute size. Similarly the cGMP spatial spread is 0.7-1 microm in cone outer segments, independently of their dimensions.

Animals↗
PubMed2001

Transpapillary intraductal US prior to biliary drainage in the assessment of longitudinal spread of extrahepatic bile duct carcinoma.

BACKGROUND: The utility of intraductal US via the transpapillary route prior to biliary drainage in the assessment of longitudinal extension of extrahepatic bile duct carcinoma was investigated. METHODS: In 19 patients with extrahepatic bile duct carcinoma who underwent surgical resection, an ultrasonic probe (diameter, 2.0 mm; frequency, 20 MHz) was inserted into the bile duct via the transpapillary route prior to biliary drainage. Longitudinal cancer extension along the bile duct was prospectively determined and compared with the histologic findings in the resected specimens. RESULTS: Results on the hepatic side were as follows: Intraductal US demonstrated more extensive longitudinal cancer spread than cholangiography in 9 of 19 patients with one instance of overdiagnosis. The accuracy of intraductal US in assessing the extent of spread (84%) was superior to that of cholangiography (47%) (p < 0.05). Results on the duodenal side were as follows: In patients with suprapancreatic bile duct cancer (n = 14), intraductal US demonstrated more extensive longitudinal cancer spread than cholangiography in 8 of 14 patients. The accuracy of intraductal US in assessing the extent of the spread (86%) was superior to that of cholangiography (43%) (p < 0.05). CONCLUSIONS: Transpapillary intraductal US prior to biliary drainage is useful in demonstrating longitudinal extension of bile duct cancer. However, the surgical margins were inaccurate in some patients.

Aged↗
PubMed1997

Pinching in longitudinal and alternate osteons during cyclic loading.

Pinching is a degrading phenomenon which occurs during cyclic loading of certain materials. A change in the slope of the deflection curve reveals pinching lesions, either flexural cracks or bond degradation, cause pinching. This paper investigates pinching for 20 longitudinal and 18 alternate fully calcified osteonic samples of cylindrical shape and 500 micron length. Each sample was axially loaded beyond the proportional limit using an electromechanical device acting as a transducer of the variations in length of the sample into changes in the resonance frequency of a microwave micrometer. A cubic polynomial served as a mathematical model to investigate the stress-strain diagrams at the first and last cycles through the study of strain limits, stiffness and pinching behaviours, and energy absorption. The hysteretic behaviour of the two types of osteons differs and is far from ideal. The presence of pinching may derive from the existence of longitudinal fibrils, in particular the yielding of the incompletely calcified ones. In longitudinal osteons consisting mainly of longitudinal collagen fibrils, the deformation under compression is not protected by lamellae consisting of transverse fibrils, therefore the lesions inducing pinching are magnified. In contrast, in alternate osteons, where the fibrils having a longitudinal orientation are reduced and protected by lamellae containing transversely oriented fibrils, the lesions-inducing pinching are lessened.

Adult↗