Bean and Pea Plastoglobules Change in Response to Chilling Stress

Plastoglobules (PGs) might be characterised as microdomains of the thylakoid membrane that serve as a platform to recruit proteins and metabolites in their spatial proximity in order to facilitate metabolic channelling or signal transduction. This study provides new insight into changes in PGs isolated from two plant species with different responses to chilling stress, namely chilling-tolerant pea (Pisum sativum) and chilling-sensitive bean (Phaseolus coccineus). Using multiple analytical methods, such as high-performance liquid chromatography and visualisation techniques including transmission electron microscopy and atomic force microscopy, we determined changes in PGs' biochemical and biophysical characteristics as a function of chilling stress. Some of the observed alterations occurred in both studied plant species, such as increased particle size and plastoquinone-9 content, while others were more typical of a particular type of response to chilling stress. Additionally, PGs of first green leaves were examined to highlight differences at this stage of development. Observed changes appear to be a dynamic response to the demands of photosynthetic membranes under stress conditions.

Too rigid to fold: Carotenoid-dependent decrease in thylakoid fluidity hampers the formation of chloroplast grana

In chloroplasts of land plants, the thylakoid network is organized into appressed regions called grana stacks and loosely arranged parallel stroma thylakoids. Many factors determining such intricate structural arrangements have been identified so far, including various thylakoid-embedded proteins, and polar lipids that build the thylakoid matrix. Although carotenoids are important components of proteins and the lipid phase of chloroplast membranes, their role in determining the thylakoid network structure remains elusive. We studied 2D and 3D thylakoid network organization in carotenoid-deficient mutants (ccr1-1, lut5-1, szl1-1, and szl1-1npq1-2) of Arabidopsis (Arabidopsis thaliana) to reveal the structural role of carotenoids in the formation and dynamics of the internal chloroplast membrane system. The most significant structural aberrations took place in chloroplasts of the szl1-1 and szl1-1npq1-2 plants. Increased lutein/carotene ratio in these mutants impaired the formation of grana, resulting in a significant decrease in the number of thylakoids used to build a particular stack. Further, combined biochemical and biophysical analyses revealed that hampered grana folding was related to decreased thylakoid membrane fluidity and significant changes in the amount, organization, and phosphorylation status of photosystem (PS) II (PSII) supercomplexes in the szl1-1 and szl1-1npq1-2 plants. Such changes resulted from a synergistic effect of lutein overaccumulation in the lipid matrix and a decreased level of carotenes bound with PS core complexes. Moreover, more rigid membrane in the lutein overaccumulating plants led to binding of Rubisco to the thylakoid surface, additionally providing steric hindrance for the dynamic changes in the level of membrane folding.

Ultrasound image of healthy skin in newborns in the first 24 hours of life

Introduction

Ultrasound imaging is a safe, repeatable and easily available imaging procedure. Based on these qualities, it may become a useful tool for skin assessment in newborns. Aims: The aim of the study was to evaluate the usefulness of high-frequency ultrasound imaging for neonatal skin assessment. Another aim was to identify differences in ultrasound features of the skin in newborns depending on the examination site, sex, age, birth weight, and arterial blood gas results.

Material and method

A total of 72 newborns in the first 24 hours of life, without any skin lesions, were included in the study. All newborns underwent ultrasound skin examinations in three body sites (forearm, abdomen and thigh) during the first 24 hours of life. DermaMed Ultrasound Scanner with a 48 MHz probe was used for imaging. A total of three structures were identified in the ultrasound images: epidermal echo, dermis, and subcutaneous tissue. The study assessed the thickness of the epidermis and dermis, and the echogenicity of the dermis and subcutaneous tissue. Data were analysed to determine possible links with sex, post-conceptional age, body weight, birth route, and results of umbilical cord blood gas analysis.

Results

Depending on the body site examined, the mean epidermal thickness was 0.081 to 0.083 mm, while the mean thickness of the dermis ranged between 0.679 and 0.722 mm. The newborns with higher birth weights were shown to have a thicker epidermis regardless of the examined site [R (correlation coefficient) for the forearm: 0.47 (p <0.001), abdomen: 0.53 (p <0.001), thigh: 0.48 (p <0.001)]. A positive correlation was found between epidermal and dermal thickness (R = 0.34; p = 0.004), but a comparison of the three examined sites revealed no significant differences in the thickness of the two structures. The sex of the newborn had no significant effect on the ultrasound features of the skin. None of the ultrasound parameters under study was found to correlate with the pH level in umbilical cord blood gas analysis. Subcutaneous oedema was detected in the examined sites in all the newborns studied.

Conclusions

High-frequency ultrasound imaging may become a useful method for neonatal skin assessment, complementing existing diagnostic techniques for monitoring pathologically altered skin.

Plastoglobules - Underestimated Components of the Plant Cell

Plastoglobules (PGs), as important components of plastids, are involved in many stages of their development: from the chloroplast biogenesis through the chloroplast-chromoplast transformations, and finally in the process of gerontoplast formation. The unique protein and lipid composition of these structures, depending on their location, suggests that PGs are both a reservoir of spare materials and a center for many metabolic reactions. Plastoglobules play an active role in the metabolism of prenylquinones, carotenoids, and jasmonic acid, and are responsible for recycling of the thylakoid disintegration products. Their direct connection with the thylakoids allows for tight relationships between these two structures and redistribution of materials, which contributes to PGs’ role in response to stressful conditions. Moreover, strongly hydrophobic nature of plastoglobules, their specific proteome and a sufficiently simple isolation procedure create extraordinary possibilities of their application in plant biotechnology.

Galactolipid deficiency disturbs spatial arrangement of the thylakoid network in Arabidopsis thaliana plants

The chloroplast thylakoid network is a dynamic structure which, through possible rearrangements, plays a crucial role in regulation of photosynthesis. Although the importance of the main components of the thylakoid membrane matrix, galactolipids, in the formation of the network of internal plastid membrane was found before, the structural role of monogalactosyldiacylglycerol (MGDG) and digalactosylidacylglycerol (DGDG) is still largely unknown. We elucidated detailed structural modifications of the thylakoid membrane system in Arabidopsis thaliana MGDG- and DGDG-deficient mutants. An altered MGDG/DGDG ratio was structurally reflected by formation of smaller grana, local changes in grana stacking repeat distance, and significant changes in the spatial organization of the thylakoid network compared with wild-type plants. The decrease of the MGDG level impaired the formation of the typical helical grana structure and resulted in a 'helical-dichotomic' arrangement. DGDG deficiency did not affect spatial grana organization but changed the shape of the thylakoid membrane network in situ from lens like into a flattened shape. Such structural disturbances were accompanied by altered composition of carotenoid and chlorophyll-protein complexes, which eventually led to the decreased photosynthetic efficiency of MGDG- and DGDG-deficient plants.

Dark-chilling induces substantial structural changes and modifies galactolipid and carotenoid composition during chloroplast biogenesis in cucumber (Cucumis sativus L.) cotyledons

Plants in a temperate climate are often subject to different environmental factors, chilling stress among them, which influence the growth especially during early stages of plant development. Chloroplasts are one of the first organelles affected by the chilling stress. Therefore the proper biogenesis of chloroplasts in early stages of plant growth is crucial for undertaking the photosynthetic activity. In this paper, the analysis of the cotyledon chloroplast biogenesis at different levels of plastid organization was performed in cucumber, one of the most popular chilling sensitive crops. Influence of low temperature on the ultrastructure was manifested by partial recrystallization of the prolamellar body, the formation of elongated grana thylakoids and a change of the prolamellar body structure from the compacted "closed" type to a more loose "open" type. Structural changes are strongly correlated with galactolipid and carotenoid content. Substantial changes in the galactolipid and the carotenoid composition in dark-chilled plants, especially a decrease of the monogalactosyldiacylglycerol to digalactosyldiacylglycerol ratio (MGDG/DGDG) and an increased level of lutein, responsible for a decrease in membrane fluidity, were registered together with a slower adaptation to higher light intensity and an increased level of non-photochemical reactions. Changes in the grana thylakoid fluidity, of their structure and photosynthetic efficiency in developing chloroplasts of dark-chilled plants, without significant changes in the PSI/PSII ratio, could distort the balance of photosystem rearrangements and be one of the reasons of cucumber sensitivity to chilling.

Comparative in vitro study of calcium phosphate ceramics for their potency as scaffolds for tissue engineering

BACKGROUND

Calcium phosphate ceramics have been widely considered as scaffolds for bone tissue engineering. Selection of the best support for cultured cells, crucial for tissue engineered systems, is still required.

OBJECTIVE

We examined three types of calcium phosphate compounds: α-tricalcium phosphate - the most soluble one, carbonate hydroxyapatite - chemically the most similar to the bone mineral and biphasic calcium phosphate - with the best in vivo biocompatibility in order to select the best support for osteoblastic cells for tissue engineered systems.

METHODS

Human osteoblasts were tested in direct contact with both dense samples and 3D scaffolds in either static or dynamic culture. Cell viability, cell spreading, osteogenic cell capacity, and extracellular matrix production were examined.

RESULTS

The obtained data indicate that biphasic calcium phosphate is the optimal cell-supporting material. In addition, dynamic culture improved cell distribution in the scaffolds, enhanced production of the extracellular matrix and promoted cells osteogenic capacity.

CONCLUSIONS

Biphasic calcium phosphate should be recommended as the most suitable matrix for osteogenic cells expansion and differentiation in tissue engineered systems.

[20-year-long experience in the large-scale fronto-lateral laryngectomy with a simultaneous reconstruction by muco-cartilagenous nasal septum flap: results of 460 cases]

The late results of the larynx reconstruction by means of the mucoseptal nasal graft after an enlarged fronto-lateral laryngectomy were described. The analysis of 460 patients showed a satisfying larynx lumen in almost all cases. In 21 cases due to the neoplasm recurrence a total laryngectomy were performed. The voice after surgery was socially good, and the wide larynx lumen was obtained.

[Foreign bodies in the esophagus]

1496 patients with foreign bodies of esophagus, reported between 1945-1997 to ENT Department of K. Marcinkowski University of Medical Sciences, were analysed. The age ranged from 0.5 to 95 years, but the most numerous group was under 5 years of age. Men outnumber women. Very detailed anamnesis, oropharynx and hypopharynx examination, neck palpation, chest X-ray were crucial for diagnosis. More than 50% of patients reported within first 10 hours after foreign body wedged. The most often met foreign bodies were: bones, coins, denture, fish bones, fruit-stones, buttons. The most dangerous were supposed to be: needles, pieces of glass, springing anchores, safety razors. Foreign bodies were removed by means of rigid esophagoscopes. In 75.3% foreign bodies occupied the first isthmus. Serious complications met in the analysed material, included: esophageal wall perforation [27], mediastinitis [21], aortal hemorrhage [3], esophagus-tracheal fistula [1]. Intramural abscesses, posteriol pharyngeal wall abscesses were found more often. 98% of esophageal foreign bodies were removed by the same route they had been introduced.

[Foreign bodies in the lower respiratory tract: experience based on materials gathered in the ENT department of the Poznań Higher School of Medical Sciences between 1945 and 1997]

258 foreign bodies were removed from the lower respiratory tract in ENT Department of Poznań High School of Medical Sciences between 1945 and 1997. The age ranged from 0 to 85 years, but the most numerous group (68%) was found between 0 and 10 years. 86.5% patients were admitted to hospital during first three days after inserting the foreign body. The longest time of foreign body existence inside the bronchus was a period of 18 years. The most often met foreign bodies were: bones, bean seeds, fruit stones, pieces of food, iron nails. Spontaneous evacuation of the foreign body took place in 4% of cases. 98% of foreign bodies were removed by means of rigid bronchoscopy. Bronchofiberoscopy was performed for diagnostic purposes or for taking out foreign bodies located in the peripheral parts of the bronchial tree. 3% of patients were referred to the further toracosurgery treatment.

[Sex-dependence of larynx susceptibility to tobacco smoke carcinogens. The role of androgen hormones]

According to epidemiological data concerning laryngeal cancer there is almost ninefold higher morbidity in male population than in females. The aim of this study was to analyse on molecular level the genotoxic effects arising under the same exposure to tobacco smoke in males and females. In biopsies received from laryngectomy material we determined levels of aromatic and alkylated DNA adducts in tumours and in adjacent non-tumour tissue. It was established that levels of DNA adducts found in male DNA samples exceeded those in female DNA samples 1.5-3.8 times, which was recognised as a molecular evidence for epidemiological differences. Next, testosterone and sex hormones binding globulin (SHBG) were determined in male subjects blood serum. The levels of testosterone and SHBG very weakly correlated with DNA adduct levels even when subjects were separated into age groups. It is concluded that levels of testosterone and SHBG are not the proper markers of individual susceptibility to genotoxicity of tobacco smoke carcinogens.

[Acute fibromatosis from the standpoint of otolaryngology]

Aggressive fibromatosis in the otolaryngological region is a curious clinical entity, demanding accurate histopathologic interpretation. It is rare connective tissue tumor, which growth infiltratively with a destructive biological behaviour similar to malignant tumours and a high recurrence rate. Morphologically reactive fibromatosis and fibrosarcoma should be considered amongst others in differential diagnosis. CT and MR scans are useful in determining the extent of the tumors and help to distinguish the tumor from nerves, vessels and bone. Surgery is the treatment of choice. Our observations of the course of disease in the maxillary sinus, nasal cavity and nasopharynx confirmed the date in literature.

[Correlation between the clinical stage of larynx cancer in male and female and levels of steroid hormones in serum]

264 patients with cancer of larynx, 21 female and 234 male, had a testosterone and sex hormone binding globulin (SHBG) before the treatment in serum estimated. Because of dependence of levels of hormones the group of patients was divided into three following groups: "lower than standard", "standard", "higher than standard". The correlation between these groups and sex, age, localization of tumor, organs' advances, stage of morphological malignancy and type of cancer was reported. Anomalous values of testosterone were in male group more frequently reported. Anomalous values of SHBG were similar in male and female groups, but in the female group there was a significant majority of "lower than standard" values reported. The majority of abnormal values of testosterone and SHBG was described in groups of age higher than 50 years. There were no differences in testosterone and SHBG levels in different localization of tumors in larynx. In advanced stage T3 and T4 there were more frequent lower mean values of testosterone levels and higher values of SHBG levels in comparison to T2 stages. In tumors in G1 and G2 stages of histological malignancy higher levels of SHBG and higher mean levels of testosterone. The tumors in stage G3 the hormone levels were lowers were observed. The levels of SHBG in groups of carcinoma planoepitheliale keratodes were in 66% higher than in a group of carcinoma planoepitheliale akeratodes but in both groups the levels of testosterone were nearing the same. In group of patients with larynx cancer the negative correlation between the levels of testosterone and SHBG was not observed. Higher SHBG levels were not always accompanied by lower testosterone levels.

[Personal experiences with extended frontolateral laryngectomy and simultaneous reconstruction using a cartilage/mucous membrane transplant from the nasal septum]

From 1979 to 1992, 219 extended frontolateral laryngectomies were performed in Poznań with simultaneous reconstruction of the larynx using a mucochondral nasal septum flap. During following examinations local recurrences were observed in 7 cases and metastases to regional lymph nodes were found in 3 cases. Complete healing of the flap was seen in 172 patients. In these cases the laryngeal lumen was found to be wide and the transplanted mucosa was normal. In 14 patients there appeared to be partial rotation of the flap, narrowing the reconstructed lumen. Among the causes of failure were the use of a too flexible, thin septal cartilage and wound infection. Detailed acoustic recordings of postoperative voices are presented as examples of successful surgery.

[Cardiomyopathy in the course of treating Hodgkin's disease in a 12-year old girl]

A case of a 12 year old girl with Hodgkin's disease is described. In the course of her illness congestive cardiomyopathy developed. The authors discuss many possible etiologies of congestive cardiomyopathy in this case with special referral to the cardiotoxicity of antineoplastic drugs.

[Lipid metabolism in patients with insulin dependent diabetes. IV. Effect of sex, age, excess body weight, duration of diabetes, insulin dosage and family history on lipid metabolism in patients with insulin dependent diabetes]

The levels of the following blood serum lipid constituents: total cholesterol, triglycerides, phospholipids, HDL-cholesterol, apolipoproteins AI, AII and B, and lipoprotein fractions have been determined in patients with insulin-dependent diabetes in relation to sex, age, duration of diabetes, coexistence of obesity, insulin dosage and history of genetic predispositions. The age of the patients was between 1.3 and 22 years and the duration of the disease ranged between 3 months and 15 years. The analysis of the results revealed that sex, age, daily insulin dose and the known genetic predispositions have no influence on the values of the parameters of lipid metabolism. However, an increase in the levels of cholesterol, HDL-cholesterol, triglycerides and apolipoproteins AI and B was observed along with the progressing duration of the disease. An increase in the levels of cholesterol, apolipoprotein B and beta-lipoprotein, and a decrease in the level of alpha-lipoprotein have been found in diabetic children with coexisting obesity. The above analysis indicates that besides metabolic control of diabetes its duration and accompanying obesity may negatively influence the course of the disease contributing to the precocious development of atherosclerosis.

[Lipid metabolism in patients with insulin dependent diabetes. III. Effect of metabolic control of diabetes on the concentration of some blood serum lipid constituents in patients with insulin dependent diabetes]

The levels of the following blood serum lipid constituents: total cholesterol, triglycerides, phospholipids, HDL-cholesterol, lipoprotein fractions, as well as apolipoproteins AI, AII and B, have been determined in patients with insulin-dependent diabetes lasting from 3 months to 15 years in relation to the degree of metabolic control characterized by the levels of fructosamine and glycosylated hemoglobin HbA1c. The group of patients having the level of HbA1c exceeding 10% was characterized by significantly higher levels of cholesterol, triglycerides and Apo-B, and lower content of alpha-lipoprotein as compared to the group with HbA1c level beneath 10%. When fructosamine concentration was considered as an index of metabolic control of diabetes, it was found that the levels of cholesterol, phospholipids and apolipoproteins apo-A and apo-AI are highest in the group with the poor metabolic control and differ significantly from the respective values found in patients with mediocre and good metabolic control. Considering biological role of the individual lipids and lipoproteins, it should be stressed that the proper control of glycaemia is important for preventing the development of atherosclerosis in patients with insulin-dependent diabetes.

[Lipid metabolism in children and adolescents with insulin dependent diabetes. II. Evaluation of changes in lipoprotein A-I in children and adolescents with insulin dependent diabetes]

The levels of lipoprotein A-I (LP A-I) containing apolipoprotein A-I (apo A-I) and devoid of apolipoprotein A-II (apo A-II) have been determined in a group of 86 children and adolescents with insulin-dependent diabetes of age between 1.3 and 22 years. The duration of diabetes in the studied group ranged between 0.25 and 15 years. The patients studied were further divided into subgroups taking into account the duration of diabetes as well as the occurrence of complications of diabetes, obesity and predisposition to early development of atherosclerosis in family history. The analysis of the results took into account the relations between the levels of LP A-I and other parameters of lipid metabolism like cholesterol, triglycerides, HDL-cholesterol, apo A-I and apo A-II concentrations as well as the effectiveness of metabolic control of diabetes. LP A-I concentration was the lowest in group of children with diabetes lasting up to one year. This parameter was correlated positively with the levels of HDL-cholesterol and apo A-I, and negatively with HbA1c. It was not related to the coexisting complications, obesity or predisposition to atherosclerosis in family history. The above results indicate that the state of metabolic control of diabetes significantly influences the level of LP A-I. Considering the importance of LP A-I in preventing atherosclerosis it should be stressed that a decrease in its level during the period of prolonged hypoglycemia constitutes still another risk factor for development of atherosclerosis in diabetic children and adolescents.

[State of lipid metabolism in children and adolescents with insulin-dependent diabetes. I. Evaluation of lipoprotein (A) behavior in children and adolescents with insulin-dependent diabetes]

The level of lipoprotein Lp(a), one of the risk factors of atherosclerosis, was determined in 91 children and adolescents of age ranging from 3.3 to 22 years suffering from insulin-dependent diabetes. The changes in Lp(a) were analyzed in relation to the group of patients, the duration of diabetes, possible genetic factors, other factors predisposing to early onset of atherosclerosis, and occurrence of obesity in the analyzed group. The relation between the level of Lp(a) and other parameters of lipid metabolism (total cholesterol, triglycerides, phospholipids, HDL-cholesterol and apolipoprotein B) as well as a degree of metabolic normalization of diabetes (as assessed by the determination of glycosylated hemoglobin and fructosamine) was studied in addition. No relation between Lp(a) and the factors mentioned above, with exception of glycosylated hemoglobin and fructosamine concentrations, could be demonstrated. The elevated level of Lp(a) in children and adolescents during the period of poor metabolic control of diabetes may constitute an additional risk factor for early onset of atherogenic changes.

[Tests evaluating the influence of plasma fatty acid composition on the dynamics of contractions of the left heart ventricle in children with simple obesity. Part I. Influence of plasma fatty acid composition in children with simple obesity]

Percent composition of the plasma fatty acids in 48 children with simple obesity was determined with gas-chromatography. Thirty seven healthy, normotensive children served as the control group. An increased content of the saturated fatty acids and decreased content of the unsaturated fatty acids together with the decrease in unsaturated fatty acids:multi-unsaturated fatty acids ratio were seen in children with simple obesity.

[Tests evaluating the influence of plasma fatty acid composition on dynamics of the left heart ventricle in children with simple obesity. Part II. The composition of plasma fatty acid percentage and behavior of left heart ventricular contraction in obese children]

Plasma fatty acids contents and dynamics of the left cardiac ventricle contractions were determined in 48 children with simple obesity. Significant deterioration of the dynamics of left ventricle contractions was seen in obese children. It included prolongation of QSIIJ, QI, and PEPI and shortening of LVETI. Correlation of the total contraction time, pre-ejection period and contractility index with plasma saturated and unsaturated fatty acids levels has been demonstrated.

Assessment of the character and incidence of electrocardiographic changes in children with simple obesity

The studied group comprised 82 children with simple obesity. In the group the character and frequency of ECG changes in 12 conventional leads were analyzed. A correlation was established between the character and frequency of these changes and the degree of overweight and obesity duration. In children with simple obesity a considerable prevalence was observed of disturbances of sinus rhythm, impairment of intraventricular conduction and signs of left ventricular hypertrophy. The observed changes were more frequent in children with over 5 years of obesity duration. No correlation was demonstrated between the incidence of these changes and the degree of overweight.

Cardiac chambers and their walls in cardiomyopathies as evaluated with CT

Thirty-two patients with cardiomyopathy, 25 with hypertrophic and 7 with dilated form were examined by cardiac catheterisation, left ventriculography, selective coronary angiography and ungated cardiac computed tomography. Diffuse hypertrophy, localized hypertrophy and dilated cardiomyopathy were diagnosed and assessed quantitatively based on CT linear, surface and volumetric parameters of cardiac morphology. Absolute septal thickness and left ventricular mass measured in CT image are the most discriminative attributes.

Cardiac atria and their appendages in mitral disease. ACT study

After a bolus injection of contrast medium 15 patients with mitral disease were scanned with 10 to 15 degrees caudal inclination of the gantry. Optimal visualisation of atrial appendages and good visualisation of the atria and pulmonary veins was achieved. CT detection and localization of atrial thrombi was verified surgically; sensitivity was 75 percent and specificity was 92 percent.

Severe anaemia: its CT findings in the cardiovascular system

Computed tomography of the upper abdomen and of the heart was performed in 21 patients with severe anemia (mean haematocrit value 0.23, mean haemoglobin content 39.6%). Gross morphology of the heart and great vessels (wall thickness, size of the chambers, lumina and walls of the vessels) were visualized in all patients without the use of contrast media. The smallest discernible difference between the normal heart muscle and blood filling its cavities was about 6-8 H and the smallest discernible difference between the aorta and the aortic blood was about 8-10 H (window width 150 H, window level 50 H). There were no CT signs of haemochromatosis of the heart, while CT measurements were highly suggestive of liver haemochromatosis in several cases. Visual evaluation of liver density in comparison to the density of blood in hepatic and portal vessels is misleading.

A CT evaluation of the intraperitoneal fluid distribution

The intraperitoneal distribution of fluid and its detectability with a CT scanning were investigated in 13 patients during infusion of dialysate for peritoneal dialysis. An ascending pattern of spread i.e. from the lesser pelvis through the inframesocolic compartment to the supramesocolic compartment prevailed. Accumulation of fluid in the perihepatic space and in Morison's pouch as a function of fluid volume is at best approximated by a parabolic curve. Fifty to two hundred fifty ml. of fluid were detectable with a CT scanning in supine position in the majority of cases within the perihepatic space and Morison's pouch. The lowest amount of fluid detectable in the peritoneal cavity--25 ml. was found between the anterior abdominal wall and bowel loops in right decubitus.