P3502Transmission electron microscopy reveals ultrastructural differences between reticulated and non-reticulated human platelets

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
L Hille ◽  
T Nuehrenberg ◽  
M Lenz ◽  
A Vlachos ◽  
D Trenk
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Golgi Apparatus ◽  
Rough Endoplasmic Reticulum ◽  
Human Platelets ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Dense Granules ◽  
Increased Risk

Abstract Reticulated platelets (RP) are the youngest circulating platelets in blood. Compared to older platelets, RP represent a highly active prothrombotic platelet population associated with an increased risk for cardiovascular events, mortality and impaired response to antiplatelet drugs compared to older platelets (non-RP). The underlying mechanisms for these characteristics of RP are so far poorly understood. This study aimed to characterize ultrastructural properties of RP and non-RP by transmission electron microscopy (TEM) of FACS-sorted human platelets using a novel staining method for RP. Washed platelets from three healthy donors were stained by SYTO™13, a nucleic acid binding fluorescent dye, which enables determination of RP and non-RP based on their RNA-content. 8×106 platelets were fixed, sorted and sandwiched between two layers of agarose gel. Samples were further processed for visualization by TEM. In total, 1047 platelets, i.e., electron micrographs of individual cross-sections, were analysed by an investigator blinded concerning experimental condition. Sizes, numbers of α-granules, dense granules, mitochondria and open canalicular system openings were assessed in RP and non-RP, respectively. Furthermore, platelets were screened for pseudopodia formation as an indicator for activation. Cross-sectional area was significantly different between RP and non-RP (2.44 [1.80–3.22] vs. 1.34 [1.04–1.89] μm2; p<0.0001; median with IQR). α-granule and mitochondria amounts were higher in RP which persisted even after adjustment for platelet size (α-granules: 4.64 [3.46–5.86]/μm2 vs. 4.15 [2.87–5.26]/μm2; p<0.0001; mitochondria: 0.33±0.02 /μm2 vs. 0.12±0.01/μm2; mean ± SEM). In contrast, the amount of open canalicular system openings per square μm was higher in the non-RP group (5.82 [4.34–7.68] /μm2 vs. 5.52 [4.01–7.11] /μm2; p=0.009). Dense granule content per square μm was similar in both RP and non-RP. Pseudopodia were present in 38% (RP) respective 37% (non-RP) of platelets. Notably, golgi apparatus and rough endoplasmic reticulum which are rarely seen in platelets were detected in several RP. Analysis of TEM pictures revealed an almost 2-fold higher cross-sectional area in RP compared to non-RP. Even after adjustment for differences in size, α-granule content remained significantly higher in RP indicating a higher storage pool for prothrombotic constituents like p-selectin or von Willebrand factor. Although the relative amount of dense granules per area did not differ between the two groups, a higher absolute number of dense granules per platelet in the RP group is indicative for higher amounts of stored small molecules such as ADP, calcium or serotonin. Despite the anucleate nature of platelets, the presence of golgi apparatus and rough endoplasmic reticulum suggests the capability of protein biosynthesis in RP. These comprehensive findings provide new important insight into the ultrastructural properties of human RP. Acknowledgement/Funding PharmCompNet Baden-Württemberg: Kompetenznetzwerk Pharmakologie Baden-Württemberg

scholarly journals Sonographic Measurement of Cross-sectional Area of the Median Nerve in Academic Dentists Without Symptoms or Signs of Carpal Tunnel Syndrome

2018 ◽  
Vol 35 (2) ◽  
pp. 105-111
Author(s):  
Akram Asbeutah ◽  
Mohsen Dashti ◽  
Abdullah AlMajran ◽  
Aref Ghayyath
Keyword(s):  
Median Nerve ◽  
Statistical Significance ◽  
Working Hours ◽  
Cross Sectional Area ◽  
Dominant Hand ◽  
Sectional Area ◽  
Cross Sectional ◽  
Increased Risk ◽  
Bone Level ◽  
The Right

The objective was to evaluate the distribution of the cross-sectional area (CSA) and flattening ratio (FR) of the median nerve (MN) in asymptomatic academic dentists using ultrasonography (US). Fifty academic dentists underwent US of the MN in transverse section at the pisiform bone level and the CSA (mm2) and FR were measured bilaterally. A CSA of <10 mm2 was considered normal. Paired t-test showed no statistical significance between either hand for CSA and FR ( P> .05). Two independent t-tests showed significant statistical differences ( P= .023) between males and females in the right dominant hand for CSA. Linear correlation analysis showed no significant correlation between CSA and FR for number of years of experience or number of working hours per day in either hand ( P>.05). The CSA was abnormal in the right dominant hand in 20 (40%) of the subjects. These male academic dentists were at increased risk of having an enlarged MN without symptoms.

Reduction in myotendinous junction surface area of rats subjected to 4-day spaceflight

1992 ◽  
Vol 73 (1) ◽  
pp. 59-64 ◽  
Author(s):  
J. G. Tidball ◽  
D. M. Quan
Keyword(s):  
Endoplasmic Reticulum ◽  
Connective Tissue ◽  
Surface Area ◽  
Rough Endoplasmic Reticulum ◽  
Myotendinous Junction ◽  
Relative Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Normal Loading ◽  
Folding Factor

The surface area of myotendinous junctions (MTJs), expressed relative to the cross-sectional area of myofibrils attached to them, was determined using established morphometric techniques in which the digitlike processes of the cell at MTJs are modeled as circular paraboloids. The relative area, called the folding factor, was measured for six rats after a 4-day spaceflight and six control rats maintained in a vivarium under otherwise identical conditions. Spaceflight resulted in a significant reduction in relative MTJ surface area, from 19.7 +/- 2.3 (SD) in control animals to 13.3 +/- 2.5 for animals after spaceflight. Furthermore, space animals displayed increased numbers of fibroblasts enriched in rough endoplasmic reticulum near the MTJ, a greater number of ribosomes and mitochondria within muscle at the MTJ, and increased occurrence of lesions in the connective tissue near the MTJ. The results indicate that spaceflight, possibly through the removal of gravity-associated loading from muscle, causes a modification in MTJ structure and may result in injuries at MTJs after return to normal loading.

Development of the lateral palatal brush in larvae of Aedes aegypti (L.) (Diptera: Culicidae)

1990 ◽  
Vol 68 (7) ◽  
pp. 1454-1467 ◽  
Author(s):  
K. M. Fry ◽  
S. B. McIver
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Plasma Membrane ◽  
Golgi Apparatus ◽  
Aedes Aegypti ◽  
Rough Endoplasmic Reticulum ◽  
Light And Electron Microscopy ◽  
Fourth Instar ◽  
Muscle Fibres ◽  
Final Length

Light and electron microscopy were used to observe development of the lateral palatal brush in Aedes aegypti (L.) larvae. Development was sampled at 4-h intervals from second- to third-instar ecdyses. Immediately after second-instar ecdysis, the epidermis apolyses from newly deposited cuticle in the lateral palatal pennicular area to form an extensive extracellular cavity into which the fourth-instar lateral palatal brush filaments grow as cytoplasmic extensions. On reaching their final length, the filaments deposit cuticulin, inner epicuticle, and procuticle sequentially on their outer surfaces. The lateral palatal crossbars, on which the lateral palatal brush filaments insert, form after filament development is complete. At the beginning of development, the organelles involved in plasma membrane and cuticle production are located at the base and middle of the cells. As the filament rudiments grow, most rough endoplasmic reticulum, mitochondria, and Golgi apparatus move to the apex of the epidermal cells and into the filament rudiments. After formation of the lateral palatal brush filaments and lateral palatal crossbars, extensive organelle breakdown occurs. Lateral palatal brush formation is unusual in that no digestion and resorption of old endocuticle occurs prior to deposition of new cuticle. No mucopolysaccharide secretion by the lateral palatal brush epidermis was observed, nor were muscle fibres observed to attach to the lateral palatal crossbars, as has been suggested by other workers.

P5457Assessment of carotid cross sectional area in hypertensive patients: phenotyping and prognostic validation in the campania salute network

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
C Mancusi ◽  
R Izzo ◽  
M A Losi ◽  
E Barbato ◽  
V Trimarco ◽  
...  
Keyword(s):  
Left Ventricular ◽  
Cross Sectional Area ◽  
Older Age ◽  
Prognostic Impact ◽  
Sectional Area ◽  
Cross Sectional ◽  
Hypertensive Patients ◽  
Cox Regression Analysis ◽  
Increased Risk ◽  
Male Sex

Abstract Background Increased intima media thickness (IMT) of common carotid artery (CA) is considered the hallmark of vascular hypertension-mediated target organ damage, even though vessel remodeling due to mechanical stress can be accompanied also by changes in diameter. Purpose We developed a method computing both diameter and IMT of CA, and assessed correlates and prognostic impact of carotid cross sectional area (CCSA) in a large registry of treated hypertensive patients. Methods We selected 7049 hypertensive patients of the Campania Salute Network registry free of overt cardiovascular (CV) disease and with available CA ultrasound (54±11 yrs; 57% male). CCSA was computed as: π × [((CA diameter + 2 × (mean IMT)) / 2)]2 − π × [((CA diameter) / 2)]2. Results CCSA was considered high if >90th percentile of the sex-specific distribution (>48 mm2 in men and >41 mm2 in women). Higher CCSA correlated with older age, male sex, higher pulse pressure (PP), higher total and LDL cholesterol and presence of diabetes (p<0.01 for all). During a median follow-up of 45 months (IQR 19–92), 324 incident composite major and minor CV events occurred. In Cox regression analysis high CCSA was associated with more than 100% increased risk of incident CV events (p<0.0001, figure), independently of the effect of older age, male sex, PP>60mmHg, presence of left ventricular hypertrophy (LVH), carotid plaque (CP), and less anti-RAS therapy (p<0.05 for all). Conclusions In treated hypertensive patients, increased CCSA is associated with worse metabolic and lipid profile and predict incident CV events, independently of high PP, presence of LVH and CP.

Impact of sarcopenia on long-term prognosis of patients with esophageal cancer after surgery.

2014 ◽  
Vol 32 (3_suppl) ◽  
pp. 118-118
Author(s):  
Tsutomu Hayashi ◽  
Soji Ozawa ◽  
Kenichi Kamachi ◽  
Akihito Kazuno ◽  
Eisuke Ito ◽  
...  
Keyword(s):  
Esophageal Cancer ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Curative Surgery ◽  
Cross Sectional ◽  
Long Term Outcome ◽  
Increased Risk ◽  
The Impact ◽  
Overall Mortality

118 Background: Emerging evidence suggests that sarcopenia might have an adverse impact on the survival of patients with cancer. We herein investigated the impact of sarcopenia on the long-term outcome of patients with esophageal cancer after curative surgery by analyzing the muscle cross-sectional area using computed tomography (CT). Methods: Sarcopenia was assessed in 204 patients undergoing a macroscopic curative esophagectomy for the resection of esophageal cancer between January 2005, and December 2008 at Tokai University Hospital by measuring the cross-sectional area of the psoas muscle at the level of the third lumbar vertebra on CT images obtained before surgery. The measured total psoas area (TPA) was normalized according to the patient’s height. Sarcopenia was defined as a TPA of ≤525 mm/m2 for men, and ≤375 mm/m2 for women. The impact of sarcopenia was assessed after controlling for clinical factors using multivariate modeling. Results: The median follow-up period was 60 months. The median patient age was 64 years; 184 (90%) patients were male and 20 (10%) were female. The median TPA was 580 mm/m2 for the men and 386 mm/m2 for the women. Sixty-nine (34%) patients had sarcopenia (TPA ≤525 mm/m2 for men, 375 mm/m2 for women ). The overall five-year survival rates were 33% for the patients with sarcopenia, and 66% for those without sarcopenia. In a multivariate analysis, a low body mass index (BMI ≤ 18.5 kg/m2; hazard ratio [HR], 1.87 [P = 0.028]), pathological stage of disease (HR for stage I, 1.587 in stage II [P = 0.219], 4.146 in stage III [P < 0.001], and 6.712 in stage IV [P < 0.001]), tumor location (HR of upper thoracic for middle and lower thoracic, 2.350 [P = 0.002]), and sarcopenia (HR, 1.858 [P= 0.006]) were independently associated with the overall mortality. Conclusions: Sarcopenia is associated with an increased risk of overall mortality in esophageal cancer after curative surgery independent of tumor-specific factors and the BMI. The development of effective interventions for sarcopenia warrants further study to improve the prognosis of patients with esophageal cancer.

scholarly journals CT-Determined Sarcopenia in GLIM-Defined Malnutrition and Prediction of 6-Month Mortality in Cancer Inpatients

Nutrients ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 2647
Author(s):  
Francisco José Sánchez-Torralvo ◽  
Ignacio Ruiz-García ◽  
Victoria Contreras-Bolívar ◽  
Inmaculada González-Almendros ◽  
María Ruiz-Vico ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Muscle Mass ◽  
Nutritional Assessment ◽  
Lumbar Vertebra ◽  
Cross Sectional Area ◽  
Sectional Area ◽  
Cross Sectional ◽  
Skeletal Muscle Index ◽  
Increased Risk ◽  
Muscle Cross Sectional Area

Our objective was to evaluate the clinical application of third lumbar vertebra (L3)-computer tomography (CT)-determined sarcopenia as a marker of muscle mass in cancer inpatients diagnosed with malnutrition according to the Global Leadership Initiative on Malnutrition (GLIM) criteria and to establish its association with 6-month mortality. Methods: This was an observational, prospective study in patients from an inpatient oncology unit. We performed a nutritional assessment according to GLIM criteria, including muscle cross-sectional area at L3 by CT and skeletal muscle index (SMI). Six-month mortality was evaluated. Results: A total of 208 patients were included. The skeletal muscle cross-sectional area at L3 was 136.2 ± 32.5 cm2 in men and 98.1 ± 21.2 cm2 in women. The SMI was 47.4 ± 12.3 cm2/m2 in men and 38.7 ± 8.3 cm2/m2 in women. Sarcopenia (low SMI) was detected in 59.6% of the subjects. Using SMI as a marker of low muscle mass in application of GLIM criteria, we found 183 (87.9%) malnourished patients. There were 104 deaths (50%) at 6 months. The deceased patients had a lower skeletal muscle cross-sectional area (112.9 ± 27.9 vs. 126.1 ± 37.8 cm2; p = 0.003) and a lower SMI (41.3 ± 9.5 vs. 45.7 ± 12.9 cm2/m2; p = 0.006). An increased risk of 6-month mortality was found in malnourished patients according to GLIM criteria using SMI (HR 2.47; 95% confidence interval 1.07–5.68; p = 0.033). Conclusions: Low muscle mass, assessed by L3-CT, was observed to affect more than half of cancer inpatients. The deceased patients at 6 months had a lower skeletal muscle cross-sectional area and SMI. Malnutrition according to GLIM criteria using CT-determined sarcopenia was shown to adequately predict 6-month mortality.

Characterization of the pituitary gonadotroph cells of hypogonadal (hpg) male mice: comparison with normal mice

1982 ◽  
Vol 95 (3) ◽  
pp. 321-NP ◽  
Author(s):  
I. F. W. McDowell ◽  
J. F. Morris ◽  
H. M. Charlton
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Luteinizing Hormone ◽  
Golgi Apparatus ◽  
Rough Endoplasmic Reticulum ◽  
Male Mice ◽  
Quantitative Electron Microscopy ◽  
Luteinizing Hormone Releasing Hormone ◽  
Lh Rh

Hypogonadal (hpg) mice lack hypothalamic luteinizing hormone releasing hormone (LH-RH). Gonadotrophs from male hpg mice have been identified by immunocytochemistry for LH and quantitative electron microscopy allied with radioimmunoassay of the gonadotrophins. In comparison with those of normal mice, gonadotrophs in male hpg animals are less numerous and smaller, with less cytoplasm and rough endoplasmic reticulum and a smaller Golgi apparatus. They have fewer granules, especially those of larger (> 210 nm) diameter. Thus, in the absence of LH-RH, gonadotrophs can differentiate but remain relatively inactive.

scholarly journals Uncinate Process Area as a New Sensitive Morphological Parameter to Predict Cervical Neural Foraminal Stenosis

2019 ◽  
Vol 2 (22.2) ◽  
pp. E105-E110
Author(s):  
Young Uk Kim
Keyword(s):  
Characteristic Curve ◽  
Uncinate Process ◽  
Cross Sectional Area ◽  
Control Group ◽  
Foraminal Stenosis ◽  
Morphological Parameter ◽  
Sectional Area ◽  
Cross Sectional ◽  
Increased Risk ◽  
Uncovertebral Joint

Background: Hypertrophy of the uncovertebral joint has been considered as a major cause of cervical neural foraminal stenosis (CNFS). The cross-sectional area of the uncinate process is a key morphologic parameter in the identification of uncovertebral joint hypertrophy. To evaluate the connection between CNFS and the uncinate process, we devised a new morphological parameter, the uncinate process area (UPA). Objective: We hypothesized that the UPA is an important morphologic parameter in the diagnosis of CNFS. Study Design: Retrospective observational study. Setting: The single center study in Incheon, Republic of Korea. Methods: UPA data were collected from 146 patients with CNFS and 197 control subjects who underwent neck computed tomography (CT) as part of a routine medical examination. Neck CT images were obtained from all subjects. The whole cross-sectional area of the bone margin of the uncinate process was measured at the C5-6 intervertebral disc level on CT scans using a picture archiving and communications system. Results: The average UPA was 15.52 mm2 in the control group and 29.97 mm2 in the CNFS group. The CNFS group displayed significantly greater UPA levels (P < 0.001). Regarding the validity of the UPA as a predictor of CNFS, the receiver operating characteristic curve analysis revealed an optimal cut-off point for the UPA of 21.15 mm2 , with 91.8% sensitivity, 93.4% specificity, and an area under the curve of 0.972 (95% CI,0.956-0.989) in the CNFS group. Limitations: Anatomically, the UP is located on the superior lateral surfaces of the C3-7 cervical vertebral bodies. However, we focused on the C5-6 uncovertebral joint level, because many previous studies revealed C6 UP has the greatest height among UP and C5-6 uncovertebral joint hypertrophy is a primary cause of CNFS. Conclusions: The newly devised UPA is a sensitive parameter for assessing CNFS. A hypertrophied UPA is associated with an increased risk of CNFS. We think that this result will be helpful for diagnostic radiology in evaluating patients with CNFS. Institutional Review Board (IRB) approval number: IS16RISI0002 Key words: Uncinate process area, cervical neural foraminal stenosis, Uncovertebral joint hypertrophy, optimal cut-off point, cross- sectional area

Modification of Pineal Ultrastructure by Exogenous Hormones

1967 ◽  
Vol 25 ◽  
pp. 170-171
Author(s):  
R. A. Turner ◽  
A. E. Rodin ◽  
D. K. Roberts
Keyword(s):  
Electron Microscopy ◽  
Endoplasmic Reticulum ◽  
Rough Endoplasmic Reticulum ◽  
Estradiol Benzoate ◽  
Female Rats ◽  
List Type ◽  
Type Number ◽  
Pregnant Rats ◽  
Gonadal Atrophy ◽  
Pineal Ultrastructure

There have been many reports which establish a relationship between the pineal and sexual structures, including gonadal hypertrophy after pinealectomy, and gonadal atrophy after injection of pineal homogenates or of melatonin. In order to further delineate this relationship the pineals from 5 groups of female rats were studied by electron microscopy:ControlsPregnant ratsAfter 4 weekly injections of 0.1 mg. estradiol benzoate.After 8 daily injections of 150 mcgm. melatonin (pineal hormone).After 8 daily injections of 3 mg. serotonin (melatonin precursor).No ultrastructural differences were evident between the control, and the pregnancy and melatonin groups. However, the estradiol injected animals exhibited a marked increase in the amount and size of rough endoplasmic reticulum within the pineal cells.

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