Light conditions inside developing buds affect floral induction

Buds of Pinus sylvestris L. and Picea abies (L.) Karst. were pierced with optical fibres allowing natural light to the vicinity of apical domes. Induction of female strobiles was achieved. Since bud scales absorb more red than far-red light, the treatment may have increased the far-red light absorbing form of phytochrome.Abbreviations Pfr far-red light absorbing form of phytochrome     

Seasonal changes in light transmission by bud scales of spruce and pine

A bundle of optical fibres and a photometer were used to measure light transmission through bud scales of Norway spruce [Picea abies (L.) Karst.] and Scots pine (Pinus silvestris L.). Percentage transmission increases with wavelength from none below 480 nm to 3% the far-red. Transmission of all wavebands measured was lowest in late summer and winter and highest in the autumn and spring. For most of the year in pine, and only from July to September in spruce, there is a depression of red light (660–670 nm) transmission. This affects the ratio of 660/730 nm light penetrating the apical domes. This ratio is lowest in July and August, at the time of initiation of female strobili. The seasonal variation in transmission of light by bud scales is discussed in relation to the possible consequences for the control of flowering.     

Basicranial flexion,relative brain size,and facial kyphosis in Homo sapiens and some fossil hominids

Comparative work among nonhominid primates has demonstrated that the basicranium becomes more flexed with increasing brain size relative to basicranial length and as the -upper and lower face become more ventrally deflected (Ross and Ravosa [1993] Am. J. Phys. Anthropol. 91:305–324). In order to determine whether modern humans and fossil hominids follow these trends, the cranial base angle (measure of basicranial flexion), angle of facial kyphosis, and angle of orbital axis orientation were measured from computed tomography (CT) scans of fossil hominids (Sts 5, MLD 37/38, OH9, Kabwe) and lateral radiographs of 99 extant humans. Brain size relative to basicranial length was calculated from measures of neurocranial volume and basicranial length taken from original skulls, radiographs, CT scans, and the literature. Results of bivariate correlation analyses revealed that among modern humans basicranial flexion and brain size/basicranial length are not significantly correlated, nor are the angles of orbital axis orientation and facial kyphosis. However, basicranial flexion and orbit orientation are significantly positively correlated among the humans sampled, as are basicranial flexion and the angle of facial kyphosis. Relative to the comparative sample from Ross and Ravosa (1993), all hominids have more flexed basicrania than other primates: Archaic Homo sapiens, Homo erectus, and Australopithecus africanus do not differ significantly from Modern Homo sapiens in their degree of basicranial flexion, although they differ widely in their relative brain size. Comparison of the hominid values with those predicted by the nonhominid reduced major-axis equations reveal that, for their brain size/basicranial length, Archaic and Modern Homo sapiens have less flexed basicrania than predicted. H. erectus and A. africanus have the degree of basicranial flexion predicted by the nonhominid reduced major-axis equation. Modern humans have more ventrally deflected orbits than all other primates and, for their degree of basicranial flexion, have more ventrally deflected orbits than predicted by the regression equations for hominoids. All hominoids have more ventrally deflected orbital axes relative to their palate orientation than other primates. It is argued that hominids do not strictly obey the trend for basicranial flexion to increase with increasing relative brain size because of constraints on the amount of flexion that do not allow it to decrease much below 90°. Therefore, if basicranial flexion is a mechanism for accommodating an expanding brain among non-hominid primates, other mechanisms must be at work among hominids. © 1995 Wiley-Liss, Inc.     

VEGF-C Is a Thyroid Marker of Malignancy Superior to VEGF-A in the Differential Diagnostics of Thyroid Lesions

Introduction

Thyroid nodular goiter is one of the most common medical conditions affecting even over a half of adult population. The risk of malignancy is rather small but noticeable–estimated by numerous studies to be about 3–10%. The definite differentiation between benign and malignant ones is a vital issue in endocrine practice. The aim of the current study was to assess the expression of vascular endothelial growth factor A (VEGF-A) and VEGF-C on the mRNA level in FNAB washouts in case of benign and malignant thyroid nodules and to evaluate the diagnostic value of these markers of malignancy.

Materials and Methods

Patients undergoing fine-needle aspiration biopsy (FNAB) in our department between January 2013 and May 2014 were included. In case of all patients who gave the written consent, after ultrasonography (US) and fine-needle aspiration biopsy (FNAB) performed as routine medical procedure the needle was flushed with RNA Later solution, the washouts were frozen in -80 Celsius degrees. Expression of VEGF-A and VEGF-C and GADPH (reference gene) was assessed in washouts on the mRNA level using the real-time PCR technique. Probes of patients who underwent subsequent thyroidectomy and were diagnosed with differentiated thyroid cancer (DTC; proved by post-surgical histopathology) were analyzed. Similar number of patients with benign cytology were randomly selected to be a control group.

Results

Thirty one DTCs and 28 benign thyroid lesions were analyzed. Expression of VEGF-A was insignificantly higher in patients with DTCs (p = 0.13). Expression of VEGF-C was significantly higher in patients with DTC. The relative expression of VEGF-C (in comparison with GAPDH) was 0.0049 for DTCs and 0.00070 for benign lesions, medians – 0.0036 and 0.000024 respectively (p<0.0001).

Conclusions

Measurement of expression VEGF-C on the mRNA level in washouts from FNAB is more useful than more commonly investigated VEGF-A. Measurement of VEGF-C in FNAB washouts do not allow for fully reliable differentiation of benign and malignant thyroid nodules and should be interpreted carefully. Further studies on larger groups are indicated. However, measurement of VEGF-C on mRNA level can bring important information without exposing patient for additional risk and invasive procedures.     

Growth dynamics of a laminated microbial mat in response to variable irradiance in an Antarctic lake

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Optimization of porcine urothelial cell cultures: Best practices,recommendations, and threats

Many experimental approaches have been conducted in order to isolate urothelial cells from bladder tissue biopsies, but each method described has utilized different protocols and sources of bladder tissue. In this study, we compared the different methods of urothelial cell isolation available in literature together with standardized methods in order to obtain more unified results. Five methods for primary porcine urothelial culture establishment were compared: tissue explants and four enzymatic methods utilizing collagenase II, dispase II, combination of dispase II and trypsin, and trypsin alone. The average number of isolated cells, cell morphology, success of established culture, average number of cells from the first passage, expression of p63 and pancytokeratin and the characterization of urothelial cell growth, and aging were analyzed during the in vitro culture. The method utilizing dispase II was the most efficient and reproducible method for the isolation and culture of porcine urothelial cells when compared to the other tested methods. Urothelial cells obtained by this method grew considerably well and the cultures were established with high efficiency, which enabled us in obtaining a large quantity of cells with normal morphology. Contamination with fibroblasts in this method was the lowest. The utilization of a proper method for urothelial cell isolation is a critical step in the urinary tract regeneration when using tissue engineering techniques. In summary, this study demonstrated that by utilizing the described method with dispase II, a suitable number of cells was achieved, proving the method useful for tissue regeneration.     

Copy number variations of genes involved in stress responses reflect the redox state and DNA damage in brewing yeasts

The yeast strains of the Saccharomyces sensu stricto complex involved in beer production are a heterogeneous group whose genetic and genomic features are not adequately determined. Thus, the aim of the present study was to provide a genetic characterization of selected group of commercially available brewing yeasts both ale top-fermenting and lager bottom-fermenting strains. Molecular karyotyping revealed that the diversity of chromosome patterns and four strains with the most accented genetic variabilities were selected and subjected to genome-wide array-based comparative genomic hybridization (array-CGH) analysis. The differences in the gene copy number were found in five functional gene categories: (1) maltose metabolism and transport, (2) response to toxin, (3) siderophore transport, (4) cellular aldehyde metabolic process, and (5) L-iditol 2-dehydrogenase activity (p < 0.05). In the Saflager W-34/70 strain (Fermentis) with the most affected array-CGH profile, loss of aryl-alcohol dehydrogenase (AAD) gene dosage correlated with an imbalanced redox state, oxidative DNA damage and breaks, lower levels of nucleolar proteins Nop1 and Fob1, and diminished tolerance to fermentation-associated stress stimuli compared to other strains. We suggest that compromised stress response may not only promote oxidant-based changes in the nucleolus state that may affect fermentation performance but also provide novel directions for future strain improvement.     

Decades of population genetic research reveal the need for harmonization of molecular markers: the grey wolf Canis lupus as a case study

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