Lobe Division Research Articles

Morphology and biometry of the thymus in Gallus gallus domesticus (Linnaeus, 1758) from the isa brow lineage

The anatomy of the thymus was described in thirty chickens (Gallus gallus domesticus) of the Isa Brow line. Samples were prepared by fixation and preservation in 10% formalin solution and analyzed by subsequent dissection. The thymus lobes were found along the ventral region of the neck from the third cervical vertebra to the proximity to the clavicular bones in relation to the vagus nerve, the common artery of the vagus nerve and the jugular vein. The number of lobes ranged from four or five to the right antimere and three to five to the left. The mean lobe size was 0.80 x 0.43 x 0.38 cm for the cranial lobe, 1.53 x 0.81 x 0.42 cm for the middle cranial lobe, 2.10 x 0.64 x 0.46 for the middle lobe, 2.29 x 0.89 x 0.59 for the middle caudal lobe and 3.82 x 1.39 x 1.11 cm for the caudal lobe in the right antimere. In the left antimere, 0.80 x 0.41 x 0.37 cm was recorded for the cranial lobe, 1.55 x 0.80 x 0.44 cm for the middle cranial lobe, 2.37 x 0.87 x 0.56 for the middle lobe, 2.37 x 0.85 x 0.60 for the middle caudal lobe and 3.89 x 1.43 x 1.08 cm for the caudal lobe. The thymus of birds from the Isa Brow lineage presented characteristics similar to those found in other lineages with respect to the division of lobes and topography. However, skeletal, syntopic and holotopic disparities were observed that indicate some unique characteristics of the thymus in this lineage.

Study on the formation and development of aromatic rice spikelets

In order to detect some of the determinants of rice flavor, an experiment was carried out that studied panicle primordia at the initial panicles of three aromatic varieties: Nang Thom Cho Dao mutation (NTCDm), Thom Bay Nui (TBN), and Jasmine-85, and IR28 was used as the control variety (non-aroma). The samples were dyed from the primordium stage to the ripe-pollen stage. Results showed that there were two key differences between the aromatic rices and the control. The first point of difference was at the primordium stage, and the second was after, as a consideration of the number of bivalents (pairs of homologous chromosomes). As for the three aromatic rice varieties, there appeared a lobe division at the branch primordium; at the diplotene stage of meiosis, and seven to eight stained bivalents appeared while the control had no lobe division and the number of stained bivalents achieved 11 to 12.

A 75-Year-Old Man with New Onset Dyspnea and Haemoptysis

Foreign body aspiration (FBA) is a common life-threatening condition which mostly occurs in children and elderly due to lack of airway protection mechanisms. A 75-year- old man was admitted to our outpatient clinic with complaints of a permanent shortness of breath for approximately 2 months and haemoptysis for two weeks. He had prescribed bronchodilators and levofloxacin with a diagnosis of COPD exacerbation but he didn't experience any relief though he used the medication regularly. He was a water-pipe smoker for 50 years. He reported to swallow 3 olive seeds in a day, after he watched an herbalist which had advised to do so, on a TV program. On presentation, wheezing was heard over the right hemi thorax and crackles were noted at the left base. His chest radiograph showed a suspicious heterogenic density behind the left heart silhouette. Bronchoscopy showed a polypoid lesion on the posterior wall of the left main bronchus, whereas an oval shaped mobile body (olive seed) was observed over the right main bronchus, under the right upper lobe division. The pathological diagnosis of the specimen taken from the polypoid lesion was compatible with active chronic granulation. We removed the olive seed by grasping forceps and the symptoms of the patient dissolved as well as the radiological findings. This is a demonstrative case reminding to consider FBA in elderly with sub acute respiratory symptoms.

Growth of foliose lichens: a review

This review considers various aspects of the growth of foliose lichens including early growth and development, variation in radial growth rate (RaGR) of different species, growth to maturity, lobe growth variation, senescence and fragmentation, growth models, the influence of environmental variables, and the maintenance of thallus symmetry. The data suggest that a foliose lichen thallus is essentially a ‘colony’ in which the individual lobes exhibit a considerable degree of autonomy in their growth processes. During development, recognisable juvenile thalli are usually formed by 15 months to 4 years while most mature thalli exhibit RaGR between 1 and 5 mm yr−1. RaGR within a species is highly variable. The growth rate-size curve of a foliose lichen thallus may result from growth processes that take place at the tips of individual lobes together with size-related changes in the intensity of competition for space between the marginal lobes. Radial growth and growth in mass is influenced by climatic and microclimatic factors and also by substratum factors such as rock and bark texture, chemistry, and nutrient enrichment. Possible future research topics include: (1) measuring fast growing foliose species through life, (2) the three dimensional changes that occur during lobe growth, (3) the cellular changes that occur during regeneration, growth, and division of lobes, and (4) the distribution and allocation of the major lichen carbohydrates within lobes.

Lobe formation and division in the foliose lichen xanthoparmelia conspersa

New lobe development and lobe division was studied in the foliose lichen Xanthoparmelia conspersa (Ehrh. ex. Ach.) Hale. In thalli with either the centre or margin removed, the inside edge of the perimeter, the outer edge of the reproductive centre, and fragments derived from the thallus perimeter all regenerated growing points (‘lobe primordia’) within a year. Thalli possessing isidia had the greatest ability to regenerate growing points. In reproductive thalli, there was a positive correlation between the density of new growing points and thallus size. When fragments were cut from the perimeters of mature X. conspersa thalli and glued to pieces of slate, the ratio of growing points to mature lobes increased over 54 months. Lobes within a thallus exhibited different degrees of bifurcation. In some bifurcating lobes, the point of origin of the bifurcation advanced at the same rate as the lobe tips over 4 months but in most lobes, the bifurcation point either advanced less rapidly than the lobe tips or retreated from its original location. Removing adjacent lobes had no significant effect on the radial growth of a lobe over 4 months or on the location of the bifurcation point but it increased the number of growing points. These results suggest that for X. conspersa: 1) all portions of of thalli can regenerate growing points, 2) few growing points actually develop into mature lobes, 3) individual lobes within a thallus grow and divide differently, and 4) adjacent lobes inhibit the development of growing points on their neighbours.

Ductal aneurysm masquerading as nonresolving pneumonia: A challenging differential!

We report here, the case of a six-and-a-half-month-old boy investigated for persistent respiratory distress and homogeneous opacity in the left upper lobe. Echocardiography revealed a giant ductal aneurysm compressing the left pulmonary artery and upper lobe division of the left bronchus. Computerized tomography angiogram delineated the exact anatomy and prompt surgical resection provided a successful cure to this lesser known entity.

Monthly fluctuations in radial growth of individual lobes of the lichenParmelia conspersa (Erhr. ex Ach.) Ach.

The radial growth (RG) of 120 lobes from 35 thalli of the foliose lichenParmelia conspersa (Ehrh. ex Ach.) Ach. was studied monthly over 22 months in south Gwynedd, Wales, UK. Autocorrelation analysis of each lobe identified three patterns of fluctuation: I) random fluctuations (58% of lobes), 2) a cyclic pattern of growth (23% of lobes), and 3) fluctuating growth interrupted by longer periods of very low or zero growth (19% of lobes). In 80% of thalli, two or three patterns of fluctuation were present within the same thallus. Growth fluctuations were correlated with climatic variables in 31% of lobes, most commonly with either total rainfall or number of rain days per month. Lobes correlated with climate were not associated with a particular type of growth fluctuation. RG of a lobe was positively correlated with the degree of bifurcation of the lobe tip. It is hypothesised that lobes ofP. conspersa exhibit a cyclic pattern of growth due in part to lobe division. The effects of climate, periods of zero growth, and microvariationsin the environment of a lobe are superimposed on this cyclic pattern resulting in the random growth of many lobes. Random growth fluctuations may contribute to the maintenance of thallus symmetry inP. conspersa.

Studies on The Growth of Lichens I Lobe Formation and the Maintenance of Circularity in Crustose Species

AbstractThe rate of lobe division during thallus enlargement in Xanthoria elegans and Diploicia canescens is considered in geometric terms. The frequency of lobe engulfment by neighbouring lobes was measured, was fitted graphically to a simple equation and was found to result from constant lobe division with thallus size. Values for a constant in the equation and derived from the observed frequency of lobe engulfment provided a measurement of a new morphological parameter: ratio lobe length to width. Greatest departure from circularity in small thalli of D. canescens occurred when thallus size did not permit lobe competition. Increasing lobe engulfment and thallus circularity in larger thalli appeared to be correlated. Circularity in crustose thalli without lobes is discussed with definitions of ‘primary’ and ‘secondary’ areoles.