The rotated-lamina syndrome. V. Partial lamina rotation and related features in Hamamelidaceae

1994 ◽  
Vol 72 (5) ◽  
pp. 626-634 ◽  
Author(s):  
W. A. Charlton
Keyword(s):  
Key Words ◽  
Shoot Apex ◽  
Leaf Development ◽  
Early Stage ◽  
Leaf Primordia ◽  
Leaf Base ◽  
Early Stages ◽  
Young Leaves

Shoots of Hamamelidaceae have been examined for the presence of the rotated-lamina syndrome, a condition in which young leaves in bud face towards one side of the shoot (normally the upper) rather than towards their own shoot apex. Early leaf development and bud organisation have been examined in representatives of eight genera with dorsiventral shoots and distichous phyllotaxis, and of four genera with radially symmetrical shoots and spiral or decussate phyllotaxis. Radially symmetrical shoots do not show any evidence of the syndrome. The distichous Corylopsis and Hamamelis species studied have leaf primordia that are asymmetrical from an early stage and show partial lamina rotation, the lamina facing obliquely towards the upper side of the bud. Mature laminae are usually asymmetrical. In Corylopsis rotation arises by torsion in the petiole region, and in Hamamelis by asymmetrical growth of the leaf base. Distichous examples without lamina rotation also have asymmetrical primordia in most cases, often have asymmetrical leaves, and all show the same asymmetrical development of the leaf base as found in Hamamelis. It is suggested that these features represent either (i) relics of rotated-lamina syndrome that was present in these cases but has been suppressed or (ii) early stages in evolution of rotated-lamina syndrome. It is suggested that suppression is the more likely interpretation. Corylopsis and Hamamelis may also be in the process of suppressing the syndrome. Key words: Hamamelidaceae, leaf, development, dorsiventrality, lamina rotation.

The rotated-lamina syndrome. IV. Relationships between rotation and symmetry in Magnolia and other cases

1994 ◽  
Vol 72 (1) ◽  
pp. 25-38 ◽  
Author(s):  
W. A. Charlton
Keyword(s):  
Key Words ◽  
Shoot Apex ◽  
Leaf Development ◽  
Leaf Primordia ◽  
The State ◽  
Axillary Buds ◽  
Reverse Direction ◽  
Ulmus Glabra ◽  
Young Leaves

Further variations of the rotated-lamina syndrome are described in Magnolia spp. and Rhamnus imeretinus, as well as an abnormal adult shoot of Ulmus glabra without lamina rotation. All magnolias investigated show lamina rotation, but there are four possible forms of shoot symmetry: (i) dorsiventral distichous shoots with the form of rotated-lamina syndrome previously described, i.e., laminae of young leaves all face towards the same (upper) side of the bud or towards the parental axis in axillary buds; (ii) another form of dorsiventral symmetry in which lamina rotation occurs in the reverse direction; (iii) spiral phyllotaxis with laminae rotated to face up the genetic spiral; and (iv) spiral phyllotaxis with laminae rotated to face down the genetic spiral. Shoot symmetry and development of lamina rotation in leaf primordia correlate with the taxo-nomic subdivision of the genus. Shoots of R. imeretinus are dorsiventral, with leaves arranged in four ranks, and lamina rotation occurs towards the upper side of the shoot. The sense of rotation of leaf primordia reverses with a periodicity of two plastochrons. In the abnormal shoot of Ulmus without lamina rotation, phyllotaxis was distichous and leaf primordia were symmetrical. The various cases are discussed in relation to the previously erected hypothesis that control of development in dorsiventral shoots with the rotated-lamina syndrome resides in alternating states of asymmetry in the shoot apex, and the corollary that a shoot with spiral phyllotaxis and one sense of lamina rotation should result if the state of asymmetry is maintained and does not alternate. Key words: Magnolia spp., Rhamnus imeretinus, Ulmus glabra, leaf, development, dorsiventrality, lamina rotation.

The rotated-lamina syndrome. VI. The range from partial to near-complete rotation in Tiliaceae and Sterculiaceae

1997 ◽  
Vol 75 (1) ◽  
pp. 170-187 ◽  
Author(s):  
W. A. Charlton
Keyword(s):  
Key Words ◽  
Shoot Apex ◽  
Leaf Development ◽  
Leaf Primordia

The rotated-lamina syndrome is a condition most commonly found in dorsiventral shoots with distichous phyllotaxis. Typically, young laminae in bud appear to be rotated to face towards the upper side of the shoot. The syndrome arises by asymmetrical growth from leaf primordia that initially face the shoot apex in approximately the normal way. It was previously described in Tilia. Further genera of Tiliaceae and the closely related Sterculiaceae were examined for the presence of the syndrome. Altogether it was found in 9 genera of the 30 examined. The syndrome is well developed in representatives of Commersonia, Corchorus, and Pterospermum, and less well developed in Luehia seemannii. Expression of the syndrome is minimal in Luehia divaricata, Theobroma, Byttneria, and Grewia. In all cases with distichous phyllotaxis that were examined in these families, the leaf primordia show at least some asymmetry in development and consequently there appears to be a predisposition to lamina rotation within the group. The syndrome is probably becoming suppressed in cases with minimal expression. The situation in dorsiventral shoots of Corchorus and Byttneria is complicated by the presence of inflorescences that arise in a leaf-opposed position. Key words: Sterculiaceae, Tiliaceae, leaf, development, dorsiventrality, lamina rotation.

The rotated-lamina syndrome. I. Ulmaceae

1993 ◽  
Vol 71 (2) ◽  
pp. 211-221 ◽  
Author(s):  
W. A. Charlton
Keyword(s):  
Leaf Blade ◽  
Early Stage ◽  
Leaf Primordia ◽  
Leaf Primordium ◽  
Foliage Leaf ◽  
Normal Orientation ◽  
Ulmus Glabra ◽  
Young Leaves ◽  
Final Orientation ◽  
Zelkova Serrata

In a number of plants, mostly woody, the components of the buds are arranged so that the laminae of the young leaves all face towards the same (upper) side of the bud, rather than towards the bud apex; in axillary buds they usually face towards the parent axis. This situation has been known for many years. For convenience, the general case is here called the rotated-lamina syndrome. There have been very few developmental investigations of how the laminae attain their unusual orientation, and these have come to different conclusions about cases in the Ulmaceae. This paper reports a detailed investigation of the syndrome in Ulmus glabra and Zelkova serrata, with comparative observations on other Ulmaceae, including cases in Celtis that do not exhibit the syndrome. The syndrome arises by different means in Ulmus and Zelkova. In Ulmus the leaf primordium is asymmetrical from the outset, the leaf blade region is obliquely dorsiventral from an early stage, and further asymmetrical growth of the leaf buttress rotates the whole leaf blade region into its final orientation as it develops. Individual shoots show heteroblastic development in progressing from bud scale to foliage leaf initiation, in increasing accentuation of the rotated-lamina syndrome, and in an increasing degree of dorsiventrality. In Zelkova, as previously described, the leaf blade region appears first as a radially symmetrical upgrowth, and it acquires dorsiventral symmetry directly in the rotated position. In Celtis spp. the lamina arises in a quite normal orientation, but reorients as it emerges from the bud. The leaf primordia of all species studied show asymmetry in other aspects, particularly in respect of stipule development, and these seem to be general features of the organisation of dorsiventral shoots. Key words: Ulmus, Zelkova, Celtis, leaf, development, dorsiventrality, lamina rotation.

Optical Properties of Hairs During the Early Stages of Leaf Development in Platanus orientalis

1996 ◽  
Vol 23 (4) ◽  
pp. 535 ◽  
Author(s):  
M Ntefidou ◽  
Y Manetas
Keyword(s):  
Optical Properties ◽  
Leaf Development ◽  
Visible Radiation ◽  
Leaf Hairs ◽  
Early Stages ◽  
Platanus Orientalis ◽  
Young Leaves ◽  
Excess Light ◽  
Dense Hair ◽  
High Reflectance

Young, developing leaves of plane (Platanus orientalis L.) possess a dense hair cover on both surfaces but, as the leaf matures, the hairs of the upper surface abscise, leading to a glabrous epidermis. Leaf hairs strongly attenuate visible radiation, partly due to high reflectance of the trichome layer and partly to the presence of an absorbing pigment, tentatively identified as the anthocyanidin peonidin, which was present in the hairs of exposed young leaves but was absent on leaves harvested from the interior of the canopy. It is suggested that leaf hairs, apart from other functions, may protect developing leaves against the photoinhibitory effect of excess light.

In vitro morphogenesis in Osmunda cinnamomea. The role of the shoot apex in early leaf development

1969 ◽  
Vol 47 (4) ◽  
pp. 575-580 ◽  
Author(s):  
G. S. Hicks ◽  
T. A. Steeves
Keyword(s):  
Shoot Apex ◽  
Leaf Development ◽  
Leaf Primordia ◽  
Shoot Apices ◽  
In Vitro Morphogenesis ◽  
Indeterminate Growth ◽  
Nutrient Culture ◽  
Determinate Growth

In sterile nutrient culture, shoot apices of the rhizome of Osmunda cinnamomea L., devoid of all visible foliar primordia, quickly give rise to dorsiventral leaf primordia at a presumptive leaf site (I1). It was established that these primordia were irreversibly determined as leaves. To examine the morphogenetic role of the shoot apex in governing early leaf development, this site was permanently isolated from the shoot apex by a single tangential cut. Usually, radially symmetrical shoots of indeterminate growth arose at I1 as a result of this surgery. By contrast, when organic continuity between I1 and the shoot apex was only temporarily interrupted by a cut which was subsequently allowed to heal, normally oriented dorsiventral leaf primordia formed most frequently at I1. These, too, were determined as leaves. It was concluded that the shoot apex serves as a source of determinative influences for the nascent primordium, imposing dorsiventrality and a pattern of determinate growth on the leaf site.

scholarly journals Platelets as messengers of early-stage cancer

2021 ◽  
Author(s):  
Siamack Sabrkhany ◽  
Marijke J. E. Kuijpers ◽  
Mirjam G. A. oude Egbrink ◽  
Arjan W. Griffioen
Keyword(s):  
Tumor Angiogenesis ◽  
Blood Test ◽  
Early Stage ◽  
Human Studies ◽  
Early Stage Cancer ◽  
Reciprocal Interaction ◽  
Early Stages ◽  
New Strategy ◽  
Mrna Content

AbstractPlatelets have an important role in tumor angiogenesis, growth, and metastasis. The reciprocal interaction between cancer and platelets results in changes of several platelet characteristics. It is becoming clear that analysis of these platelet features could offer a new strategy in the search for biomarkers of cancer. Here, we review the human studies in which platelet characteristics (e.g., count, volume, protein, and mRNA content) are investigated in early-stage cancer. The main focus of this paper is to evaluate which platelet features are suitable for the development of a blood test that could detect cancer in its early stages.

scholarly journals The expression of microRNA-331-3p and microRNA-23b3 in Egyptian patients with early-stage hepatocellular carcinoma in hepatitis C-related liver cirrhosis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Reham A. Aboelwafa ◽  
Walid Ismail Ellakany ◽  
Marwa A. Gamaleldin ◽  
Marwa A. Saad
Keyword(s):  
Hepatocellular Carcinoma ◽  
Liver Cirrhosis ◽  
Hepatitis C ◽  
Early Stage ◽  
Group Iii ◽  
Real Time Quantitative Pcr ◽  
Early Stages ◽  
Group I ◽  
Egyptian Patients ◽  
Cirrhotic Patients

Abstract Background Hepatocellular carcinoma and hepatitis C are strongly associated. The current work aimed to study the expression levels of microRNA-331-3p and microRNA-23b-3p as propable biomarkers for detecting liver cancer (HCC) at its early stages in patients with HCV-related liver cirrhosis. The current prospective study included two hundred participants, divided into three groups: group I, 100 patients with HCV-related liver cirrhosis; group II, 50 HCC patients at early stages; and group III, 50 apparentlyhealthy controls. All patients had routine laboratory workup and ultrasound hepatic assessment. Values of microRNA-331-3p and microRNA-23b-3p were measured by real-time quantitative PCR. Results Levels of miR-331-3p were significantly higher in HCC patients than in cirrhotic patients and controls (p < 0.001), while levels of miR-23b-3p were significantly lower in HCC patients compared to cirrhotics and controls (p < 0.001). ROC curve revealed that miR-23b-3p had 80% sensitivity and 74% specificity, miR-331-3p had 66% sensitivity and 61% specificity, and AFP had 64% sensitivity and 61% specificity of 61% in discrimination between HCC patients from controls. Conclusion Serum miR-23b-3p is a more effective predictor than miR-331-3p and AFP for the development of hepatocellular carcinoma in hepatitis C (HCV)-related cirrhotic patients.

scholarly journals Detection of KRAS Mutations in Circulating Tumor DNA by Digital PCR in Early Stages of Pancreatic Cancer

2016 ◽  
Vol 62 (11) ◽  
pp. 1482-1491 ◽  
Author(s):  
Nora Brychta ◽  
Thomas Krahn ◽  
Oliver von Ahsen
Keyword(s):  
Pancreatic Cancer ◽  
Early Stage ◽  
Digital Pcr ◽  
Circulating Tumor Dna ◽  
Surgical Removal ◽  
Plasma Samples ◽  
Kras Mutations ◽  
Detection Rates ◽  
Early Stages ◽  
Tumor Dna

Abstract BACKGROUND Since surgical removal remains the only cure for pancreatic cancer, early detection is of utmost importance. Circulating biomarkers have potential as diagnostic tool for pancreatic cancer, which typically causes clinical symptoms only in advanced stage. Because of their high prevalence in pancreatic cancer, KRAS proto-oncogene, GTPase [KRAS (previous name: Kirsten rat sarcoma viral oncogene homolog)] mutations may be used to identify tumor-derived circulating plasma DNA. Here we tested the diagnostic sensitivity of chip based digital PCR for the detection of KRAS mutations in circulating tumor DNA (ctDNA) in early stage pancreatic cancer. METHODS We analyzed matched plasma (2 mL) and tumor samples from 50 patients with pancreatic cancer. Early stages (I and II) were predominant (41/50) in this cohort. DNA was extracted from tumor and plasma samples and tested for the common codon 12 mutations G12D, G12V, and G12C by chip-based digital PCR. RESULTS We identified KRAS mutations in 72% of the tumors. 44% of the tumors were positive for G12D, 20% for G12V, and 10% for G12C. One tumor was positive for G12D and G12V. Analysis of the mutations in matched plasma samples revealed detection rates of 36% for G12D, 50% for G12V, and 0% for G12C. The detection appeared to be correlated with total number of tumor cells in the primary tumor. No KRAS mutations were detected in 20 samples of healthy control plasma. CONCLUSIONS Our results support further evaluation of tumor specific mutations as early diagnostic biomarkers using plasma samples as liquid biopsy.

scholarly journals Slow Motion Analysis of Repetitive Tapping (SMART) Test: Measuring Bradykinesia in Recently Diagnosed Parkinson’s Disease and Idiopathic Anosmia

2021 ◽  
pp. 1-15
Author(s):  
Cristina Simonet ◽  
Miquel A. Galmes ◽  
Christian Lambert ◽  
Richard N. Rees ◽  
Tahrina Haque ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Rating Scales ◽  
Early Stage ◽  
Slow Motion ◽  
Motor Dysfunction ◽  
Prodromal Phase ◽  
Floor Effect ◽  
Cross Sectional ◽  
Early Stages

Background: Bradykinesia is the defining motor feature of Parkinson’s disease (PD). There are limitations to its assessment using standard clinical rating scales, especially in the early stages of PD when a floor effect may be observed. Objective: To develop a quantitative method to track repetitive tapping movements and to compare people in the early stages of PD, healthy controls, and individuals with idiopathic anosmia. Methods: This was a cross-sectional study of 99 participants (early-stage PD = 26, controls = 64, idiopathic anosmia = 9). For each participant, repetitive finger tapping was recorded over 20 seconds using a smartphone at 240 frames per second. From each video, amplitude between fingers, frequency (number of taps per second), and velocity (distance travelled per second) was extracted. Clinical assessment was based on the motor section of the MDS-UPDRS. Results: People in the early stage of PD performed the task with slower velocity (p <  0.001) and with greater frequency slope than controls (p = 0.003). The combination of reduced velocity and greater frequency slope obtained the best accuracy to separate early-stage PD from controls based on metric thresholds alone (AUC = 0.88). Individuals with anosmia exhibited slower velocity (p = 0.001) and smaller amplitude (p <  0.001) compared with controls. Conclusion: We present a simple, proof-of-concept method to detect early motor dysfunction in PD. Mean tap velocity appeared to be the best parameter to differentiate patients with PD from controls. Patients with anosmia also showed detectable differences in motor performance compared with controls which may suggest that some are in the prodromal phase of PD.

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