Zebrafish Hox Paralogue Group 2 Genes Function Redundantly as Selector Genes to Pattern the Second Pharyngeal Arch

The hindbrain is a segmented structure divided into repeating metameric units termed rhombomeres (r). The Hox family, vertebrate homologs of the Drosophila HOM-C homeotic selector genes, are expressed in rhombomere-restricted patterns and are believed to participate in regulating segmental identities. Krox-20, a zinc finger gene, has a highly conserved pattern of expression in r3 and r5 and is functionally required for their maintenance in mouse embryos. Krox-20 has been shown to directly regulate the Hoxb-2 gene and we wanted to determine if it was involved in regulating multiple Hox genes as a part of its functional role. Hoxa-2 is the only known paralog of Hoxb-2, and we examined the patterns of expression of the mouse Hoxa-2 gene with particular focus on r3 and r5 in wild type and Krox-20−/− mutant embryos. There was a clear loss of expression in r3, which indicated that Hoxa-2 was downstream of Krox-20. Using transgenic analysis with E. coli lacZ reporter genes we have identified and mapped an r3/r5 enhancer in the 5′ flanking region of the Hoxa-2 gene. Deletion analysis narrowed this region to an 809 bp Bg/II fragment, and in vitro binding and competition assays with bacterially expressed Krox-20 protein identified two sites within the enhancer. Mutation of these Krox-20 sites in the regulatory region specifically abolished r3/r5 activity, but did not affect neural crest and mesodermal components. This indicated that the two Krox-20 sites are required in vivo for enhancer function. Furthermore, ectopic expression of Krox-20 in r4 was able to transactivate the Hoxa 2/lacZ reporter in this rhombomere. Together our findings suggest that Krox-20 directly participates in the transcriptional regulation of Hoxa-2 during hindbrain segmentation, and is responsible for the upregulation of the r3 and r5 domains of expression of both vertebrate group 2 Hox paralogs. Therefore, the segmental phenotypes in the Krox-20 mutants are likely to reflect the role of Krox-20 in directly regulating multiple Hox genes.

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2.2. Working Group 2: Conceptual Definitions of Reference Coordinate Systems for Earth Dynamics

International Astronomical Union Colloquium ◽

10.1017/s0252921100050867 ◽

1975 ◽

Vol 26 ◽

pp. 21-26

Keyword(s):

Coordinate System ◽

Working Group ◽

General Character ◽

Coordinate Systems ◽

Reference Coordinate System ◽

Group 2 ◽

Definition Of ◽

Earth Dynamics

An ideal definition of a reference coordinate system should meet the following general requirements:1. It should be as conceptually simple as possible, so its philosophy is well understood by the users.2. It should imply as few physical assumptions as possible. Wherever they are necessary, such assumptions should be of a very general character and, in particular, they should not be dependent upon astronomical and geophysical detailed theories.3. It should suggest a materialization that is dynamically stable and is accessible to observations with the required accuracy.

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Morphological Changes in the Rat Granulosa Cell Surface During Differentiation Induced by Estradiol and Gonadotropins

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079851 ◽

1977 ◽

Vol 35 ◽

pp. 484-485

Author(s):

P. Bagavandoss ◽

JoAnne S. Richards ◽

A. Rees Midgley

Keyword(s):

Cell Surface ◽

Granulosa Cell ◽

Morphological Changes ◽

Follicular Development ◽

Female Rats ◽

Functional Changes ◽

Group 4 ◽

Group 3 ◽

Group 5 ◽

Group 2

During follicular development in the mammalian ovary, several functional changes occur in the granulosa cells in response to steroid hormones and gonadotropins (1,2). In particular, marked changes in the content of membrane-associated receptors for the gonadotropins have been observed (1).We report here scanning electron microscope observations of morphological changes that occur on the granulosa cell surface in response to the administration of estradiol, human follicle stimulating hormone (hFSH), and human chorionic gonadotropin (hCG).Immature female rats that were hypophysectcmized on day 24 of age were treated in the following manner. Group 1: control groups were injected once a day with 0.1 ml phosphate buffered saline (PBS) for 3 days; group 2: estradiol (1.5 mg/0.2 ml propylene glycol) once a day for 3 days; group 3: estradiol for 3 days followed by 2 days of hFSH (1 μg/0.1 ml) twice daily, group 4: same as in group 3; group 5: same as in group 3 with a final injection of hCG (5 IU/0.1 ml) on the fifth day.

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Correlation of γ-radioactivity and Scanning Electron Microscopy in measurement of retention of 111Indium-labeled canine endothelial cells on synthetic vascular grafts

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100156419 ◽

1989 ◽

Vol 47 ◽

pp. 886-887

Author(s):

E.J. Prendiville ◽

S. Laliberté Verdon ◽

K. E. Gould ◽

K. Ramberg ◽

R. J. Connolly ◽

...

Keyword(s):

Blood Flow ◽

Ex Vivo ◽

Vascular Grafts ◽

Retention Data ◽

Vascular Prostheses ◽

Group 4 ◽

Human Fibronectin ◽

Insufficient Time ◽

Group 3 ◽

Group 2

Endothelial cell (EC) seeding is postulated as a mechanism of improving patency in small caliber vascular grafts. However the majority of seeded EC are lost within 24 hours of restoration of blood flow in previous canine studies . We postulate that the cells have insufficient time to fully develop their attachment to the graft surface prior to exposure to hemodynamic stress. We allowed EC to incubate on fibronectin-coated ePTFE grafts for four different time periods after seeding and measured EC retention after perfusion in a canine ex vivo shunt circuit.Autologous canine EC, were enzymatically harvested, grown to confluence, and labeled with 30 μCi 111 Indium-oxine/80 cm 2 flask. Four groups of 5 cm x 4 mm ID ePTFE vascular prostheses were coated with 1.5 μg/cm.2 human fibronectin, and seeded with 1.5 x 105 EC/ cm.2. After seeding grafts in Group 1 were incubated in complete growth medium for 90 minutes, Group 2 were incubated for 24 hours, Group 3 for 72 hours and Group 4 for 6 days. Grafts were then placed in the canine ex vivo circuit, constructed between femoral artery and vein, and subjected to blood flow of 75 ml per minute for 6 hours. Continuous counting of γ-activity was made possible by placing the seeded graft inside the γ-counter detection crystal for the duration of perfusion. EC retention data after 30 minutes, 2 hours and 6 hours of flow are shown in the table.

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Ultrastructural Immunocytochemistry of Five Rat Pituitary Adenomas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600003147 ◽

1980 ◽

Vol 38 ◽

pp. 724-725

Author(s):

D. J. McComb ◽

N. Ryan ◽

E. Horvath ◽

K. Kovacs ◽

E. Nagy ◽

...

Keyword(s):

Pituitary Adenomas ◽

Pituitary Tumors ◽

Electron Microscopic ◽

Electron Microscopic Immunocytochemistry ◽

Transmission Electron ◽

Rat Pituitary ◽

Radiation Induced ◽

Group 5 ◽

Group 2 ◽

Microscopic Techniques

Conventional light and electron microscopic techniques failed to clarify the cellular composition and derivation of spontaneous and induced, intrasellar and transplanted pituitary adenomas in rats (1). In the present work, electron microscopic immunocytochemistry was applied to evaluate five adenohypo-physial tumors using a technique described by Moriarty and Garner (2). Spontaneously occurring pituitary adenomas (group 1) were harvested from aging female Long-Evans rats. R-Amsterdam rats were treated with 2 x 1.0 mg estrone acetate (HogivaI) s.c. weekly for 6 months. Pituitary adenomas in excess of 30 mg were removed from these animals to make up the tumors of group 2. Groups 3 and 4 consisted of estrogen-induced autonomous transplan¬ted pituitary tumors MtT.WlO and MtT.F4. Group 5 was a radiation-induced transplanted autonomous pituitary tumor MtT.W5. The tumors of groups 3,4 and 5 were allowed to proliferate in host rats 6-8 weeks prior to removal for processing. Tissue was processed for transmission electron microscopy (glutaraldehyde fixation, OsO4 postfixation and epoxy resin embedding), and electron microscopic immunocytochemistry (3% paraformaldehyde fixation and Araldite embedding).

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In-vivo evaluation of the effect of cyanoacrylate on prosthetic vascular graft infection – does cyanoacrylate increase the severity of infection?

VASA ◽

10.1024/0301-1526/a000867 ◽

2020 ◽

Vol 49 (4) ◽

pp. 281-284

Author(s):

Atıf Yolgosteren ◽

Gencehan Kumtepe ◽

Melda Payaslioglu ◽

Cuneyt Ozakin

Keyword(s):

Vascular Graft ◽

Graft Infection ◽

Vascular Graft Infection ◽

Group 4 ◽

Significant Difference ◽

Group 3 ◽

Group 2 ◽

Prosthetic Vascular Graft Infection ◽

Group 1

Summary. Background: Prosthetic vascular graft infection (PVGI) is a complication with high mortality. Cyanoacrylate (CA) is an adhesive which has been used in a number of surgical procedures. In this in-vivo study, we aimed to evaluate the relationship between PVGI and CA. Materials and methods: Thirty-two rats were equally divided into four groups. Pouch was formed on back of rats until deep fascia. In group 1, vascular graft with polyethyleneterephthalate (PET) was placed into pouch. In group 2, MRSA strain with a density of 1 ml 0.5 MacFarland was injected into pouch. In group 3, 1 cm 2 vascular graft with PET piece was placed into pouch and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. In group 4, 1 cm 2 vascular graft with PET piece impregnated with N-butyl cyanoacrylate-based adhesive was placed and MRSA strain with a density of 1 ml 0.5 MacFarland was injected. All rats were scarified in 96th hour, culture samples were taken where intervention was performed and were evaluated microbiologically. Bacteria reproducing in each group were numerically evaluated based on colony-forming unit (CFU/ml) and compared by taking their average. Results: MRSA reproduction of 0 CFU/ml in group 1, of 1410 CFU/ml in group 2, of 180 200 CFU/ml in group 3 and of 625 300 CFU/ml in group 4 was present. A statistically significant difference was present between group 1 and group 4 (p < 0.01), between group 2 and group 4 (p < 0.01), between group 3 and group 4 (p < 0.05). In terms of reproduction, no statistically significant difference was found in group 1, group 2, group 3 in themselves. Conclusions: We observed that the rate of infection increased in the cyanoacyrylate group where cyanoacrylate was used. We think that surgeon should be more careful in using CA in vascular surgery.

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The influence of continuous local wound infusion on postoperative pain in patients undergoing transfemoral amputation

VASA ◽

10.1024/0301-1526/a000457 ◽

2015 ◽

Vol 44 (5) ◽

pp. 381-386 ◽

Cited By ~ 1

Author(s):

Christian Uhl ◽

Thomas Betz ◽

Andrea Rupp ◽

Markus Steinbauer ◽

Ingolf Töpel

Keyword(s):

Pain Management ◽

Pilot Study ◽

Local Anaesthetic ◽

Phantom Pain ◽

Transfemoral Amputation ◽

Postoperative Wound ◽

Stump Pain ◽

Management Protocol ◽

Group 2 ◽

Group 1

Abstract. Summary: Background: This pilot study was set up to examine the effects of a continuous postoperative wound infusion system with a local anaesthetic on perioperative pain and the consumption of analgesics. Patients and methods: We included 42 patients in this prospective observational pilot study. Patients were divided into two groups. One group was treated in accordance with the WHO standard pain management protocol and in addition to that received a continuous local wound infusion treatment (Group 1). Group 2 was treated with analgesics in accordance with the WHO standard pain management protocol, exclusively. Results: The study demonstrated a significantly reduced postoperative VAS score for stump pain in Group 1 for the first 5 days. Furthermore, the intake of opiates was significantly reduced in Group 1 (day 1, Group 1: 42.1 vs. Group 2: 73.5, p = 0.010; day 2, Group 1: 27.7 vs. Group 2: 52.5, p = 0.012; day 3, Group 1: 23.9 vs. Group 2: 53.5, p = 0.002; day 4, Group 1: 15.7 vs. Group 2: 48.3, p = 0.003; day 5, Group 1 13.3 vs. Group 2: 49.9, p = 0.001). There were no significant differences between the two groups, neither in phantom pain intensity at discharge nor postoperative complications and death. Conclusions: Continuous postoperative wound infusion with a local anaesthetic in combination with a standard pain management protocol can reduce both stump pain and opiate intake in patients who have undergone transfemoral amputation. Phantom pain was not significantly affected.

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Hereditary Heparin Cofactor II Deficiency and the Risk of Development of Thrombosis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1651093 ◽

1987 ◽

Vol 57 (02) ◽

pp. 196-200 ◽

Cited By ~ 74

Author(s):

R M Bertina ◽

I K van der Linden ◽

L Engesser ◽

H P Muller ◽

E J P Brommer

Keyword(s):

Liver Disease ◽

Venous Thrombosis ◽

Healthy Volunteers ◽

Mean Value ◽

Age Group ◽

Normal Range ◽

Heparin Cofactor Ii ◽

History Of ◽

Group 2 ◽

Hereditary Nature

SummaryHeparin cofactor II (HC II) levels were measured by electroimmunoassay in healthy volunteers, and patients with liver disease, DIC, proteinuria or a history of venous thrombosis. Analysis of the data in 107 healthy volunteers revealed that plasma HC II increases with age (at least between 20 and 50 years). HC II was found to be decreased in most patients with liver disease (mean value: 43%) and only in some patients with DIC. Elevated levels were found in patients with proteinuria (mean value 145%). In 277 patients with a history of unexplained venous thrombosis three patients were identified with a HC II below the lower limit of the normal range (60%). Family studies demonstrated hereditary HC II deficiency in two cases. Among the 9 heterozygotes for HC II deficiency only one patient had a well documented history of unexplained thrombosis. Therefore the question was raised whether heterozygotes for HC II deficiency can also be found among healthy volunteers. When defining a group of individuals suspected of HC II deficiency as those who have a 90% probability that their plasma HC II is below the 95% tolerance limits of the normal distribution in the relevant age group, 2 suspected HC II deficiencies were identified among the healthy volunteers. In one case the hereditary nature of the defect could be established.It is concluded that hereditary HC II deficiency is as prevalent among healthy volunteers as in patients with thrombotic disease. Further it is unlikely that heterozygosity for HC II deficiency in itself is a risk factor for the development of venous thrombosis.

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Abnormal Haemostasis and Blood Viscosity in Malignant Hypertension

Thrombosis and Haemostasis ◽

10.1055/s-0038-1661190 ◽

1984 ◽

Vol 52 (03) ◽

pp. 253-255 ◽

Cited By ~ 11

Author(s):

C Isles ◽

G D O Lowe ◽

B M Rankin ◽

C D Forbes ◽

N Lucie ◽

...

Keyword(s):

Blood Pressure ◽

Blood Viscosity ◽

Renal Damage ◽

Antithrombin Iii ◽

Plasma Viscosity ◽

Malignant Hypertension ◽

Fibrin Deposition ◽

Group 3 ◽

Group 2 ◽

Group 1

SummaryWe have previously shown abnormalities of haemostasis suggestive of intravascular coagulation in patients with malignant hypertension, a condition associated with retinopathy and renal fibrin deposition. To determine whether such abnormalities are specific to malignant hypertension, we have measured several haemostatic and haemorheological variables in 18 patients with malignant hypertension (Group 1), 18 matched healthy controls (Group 2), and 18 patients with non-malignant hypertension (Group 3) matched for renal pathology, blood pressure and serum creatinine with Group 1. Both Groups 1 and 3 had increased mean levels of fibrinogen, factor VIIIc, beta-thrombo- globulin, plasma viscosity and blood viscosity (corrected for haematocrit); and decreased mean levels of haematocrit, antithrombin III and platelet count. Mean levels of fast antiplasmin and alpha2-macroglobulin were elevated in Group 1 but not in Group 3. We conclude that most blood abnormalities are not specific to malignant hypertension; are also present in patients with non-malignant hypertension who have similar levels of blood pressure and renal damage; and might result from renal damage as well as promoting further renal damage by enhancing fibrin deposition. However increased levels of fibrinolytic inhibitors in malignant hypertension merit further investigation in relation to removal of renal fibrin.

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Total Knee Arthroplasty after Previous Ipsilateral Hip Arthroplasty Showed Lower Clinical Outcomes and Higher Leg Length Discrepancy Perception

The Journal of Knee Surgery ◽

10.1055/s-0040-1715447 ◽

2020 ◽

Author(s):

Han-Jun Lee ◽

Seong Hwan Kim ◽

Nicolas Pujol ◽

Yong-Beom Park

Keyword(s):

Clinical Outcomes ◽

Hip Arthroplasty ◽

Leg Length ◽

Function Score ◽

Patient’S Satisfaction ◽

Length Discrepancy ◽

Total Knee ◽

Group 2 ◽

Ks Function ◽

Group 1

AbstractThe purpose of this study is to compare perception of leg length discrepancy (LLD) and clinical results of total knee arthroplasties (TKA) in patients with or without previous ipsilateral hip arthroplasty. Between 2008 and 2015, navigation-assisted TKA was performed in 43 patients with previous hip arthroplasty after hip fracture. After 1:3 propensity score matching was performed, 108 patients of primary navigation-assisted TKA (group 1) and 36 patients with hip arthroplasty (group 2) were included. Knee Society (KS) scores, Western Ontario and McMaster Universities Index (WOMAC) scores, and patients' satisfaction including perception of LLD were evaluated. Radiographic evaluation included mechanical axis, component position, and LLD. Logistic regression analysis was performed to find the factors that affect the clinical outcomes. No significant differences in radiologic and clinical evaluations, except for KS function score, patient's satisfaction and LLD (p< 0.001), were detected between the groups. LLD and its perception were significantly higher in group 2 (1.8 ± 3.4 mm in group 1 and 9.7 ± 4.1 mm in group 2, p = 0.000). Risk factors for the low KS function score were found as LLD (odds ratio [OR]: 1.403, p = 0.008) and previous hip arthroplasty itself (OR: 15.755, p = 0.002), but much higher OR was found in previous hip arthroplasty. Although the outcomes of TKA in patients with ipsilateral hip arthroplasty are comparable to those of primary TKA, LLD was high and patient's satisfaction and functional outcomes were low in patients with previous ipsilateral hip arthroplasty. Care should be taken when considering TKA in patients with previous hip arthroplasty. This is a Level III, case control study.

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