1
|
'Barbie Tox' - A cosmetic trend with potential functional implications. Surgeon 2024; 22:e157-e158. [PMID: 38637190 DOI: 10.1016/j.surge.2024.04.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 04/01/2024] [Indexed: 04/20/2024]
|
2
|
White phosphorous civilian hand burns - An aid to timely treatment of a rare entity. Trauma Case Rep 2024; 50:100983. [PMID: 38496001 PMCID: PMC10940903 DOI: 10.1016/j.tcr.2024.100983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/03/2024] [Indexed: 03/19/2024] Open
Abstract
First discovered in 1669, white phosphorus is well known for its use in military warfare (Davis, 2002). Its application has since been expanded to include industrial disinfectants, fertilisers and fireworks (Davis, 2002). Exposure to white phosphorus can lead to severe chemical burns with high morbidity and potentially fatal systemic effects. Fortunately, civilian casualties from this potent agent are remarkably rare with few reports in the literature to date (Frank et al., 2008; Aviv et al., 2017). We present the case of a 27-year-old fisherman who sustained a chemical burn to his right hand from a substance suspected to be white phosphorus. We propose an evidence-based algorithm to guide non-military physicians literature on the acute management of white phosphorus burns to optimise timely emergency management of this uncommonly encountered substance.
Collapse
|
3
|
Coenzyme Q10, carotenoid, tocopherol, and retinol levels in cord plasma from multiethnic subjects in Hawaii. Free Radic Res 2013; 47:757-68. [PMID: 23829202 DOI: 10.3109/10715762.2013.822495] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Coenzyme Q10 (Q10), carotenoids, tocopherols, and retinol are the major circulating lipid-phase micronutrients (LPM) known to help mitigate oxidative damage and prevent chronic diseases. However, the functions of these compounds in newborns are little understood. This is due, in part, to the paucity of studies reporting their concentrations in this population. We measured Q10, carotenoids, tocopherols, and retinol in cord plasma from 100 multiethnic subjects living in Hawaii using HPLC with diode array and electrochemical detection. Appropriate internal standards were used including, for the first time, custom designed oxidized (UN10) and reduced (UL10) Q10 analogues. These compounds reflected the oxidation of UL10 to UN10 that occurred during sample processing and analysis and thus permitted accurate adjustments of natively circulating Q10 levels. All LPM measured were much lower in cord than in peripheral plasma. Cord plasma levels of total carotenoids, tocopherols, and retinol were approximately 10-fold, 3- to 5-fold and 1.5- to 3-fold lower than those in children or women. Cord plasma levels of total Q10 (TQ10; median, 113 ng/mL) were approximately 2-fold or 7- to 9-fold lower than peripheral plasma levels of neonates or children and adults, respectively. In contrast, the UN10/TQ10 ratio was substantially higher in cord (24%) than in peripheral plasma of children (3-4%) or adults (9%). Among the 5 ethnic groups in our cohort, no differences were observed in the levels of UN10, UL10, or TQ10. However, significant differences in many of the LPM were observed between ethnicities. More research is needed to explain these phenomena.
Collapse
|
4
|
Opportunities to reduce plastic surgery claims through an analysis of complaints data. J Plast Reconstr Aesthet Surg 2013; 66:455-9. [PMID: 23312235 DOI: 10.1016/j.bjps.2012.11.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2012] [Revised: 10/03/2012] [Accepted: 11/15/2012] [Indexed: 10/27/2022]
Abstract
BACKGROUND Patient expectations and demands placed on the National Health Service have significantly increased over the last decade. The analysis of adverse outcomes and measures to improve practice remain fundamental to clinical governance. We decided to investigate the reasons for plastic surgery patients making complaints and claims of negligence in order to identify trends and potential areas of improvement. METHODS In conjunction with the hospital Patient Advice and Liaison Services (PALS) and Legal Services departments, the complaints made against the Addenbrooke's Hospital Plastic Surgery Department over a 10 year period were analysed. Patients who proceeded to make formal claims of negligence were also identified and a retrospective case note review of these performed. RESULTS 185 patients made complaints between April 2000 and April 2010. The most common reasons for complaints were poor communication and treatment delays. 20 claims of negligence were made; 14 of these were patients undergoing breast surgery. There were 3 successful cases which all mentioned adverse scarring, suggesting that this risk was either not discussed or the informed consent process was inadequately documented. The financial compensation awarded ranged from £6000 to £34,000. CONCLUSIONS Poor communication is highlighted as the main reason for patients making formal complaints. Inadequate documentation of informed consent discussions may also contribute to successful negligence claims.
Collapse
|
5
|
The table tilt: preventing traction on the brachial plexus during facelift surgery. Aesthet Surg J 2012; 32:524. [PMID: 22523106 DOI: 10.1177/1090820x12442529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
6
|
Abstract
BACKGROUND The authors recently documented a significant decrease in orthognathic surgical cases performed by both plastic and oral surgeons in Ohio over a recent 5-year period. The main reason noted was related to third-party reimbursement. This is a potentially serious issue that may affect the quality of health care for patients with dentofacial deformities. Therefore, an expanded survey was conducted to determine whether this was indicative of a national trend. METHODS A three-page questionnaire was sent nationally to plastic surgeons and oral surgeons who were members of the American Society of Maxillofacial Surgery and the American Association of Oral and Maxillofacial Surgeons, respectively. Surveys requested information regarding changes in the number of orthognathic operations over a 5-year period (1999-2003) and reasons for these changes. RESULTS Of the 3273 surveys sent, 883 were returned, representing an overall response rate of 27 percent. Of the 883 returned, 771 (87.3 percent) were completed by oral surgeons and 112 (12.7 percent) were completed by plastic surgeons. The majority surveyed (70.0 percent) noted a decrease in the number of orthognathic procedures performed over a 5-year period, and 443 (77.3 percent) stated that the decrease was attributable to problems with insurance. Professional reimbursement per hour was calculated based on data collected from consecutive operations performed at the authors' institution. These data demonstrated that reimbursement per hour is significantly lower when orthognathic surgery procedures were compared with other standard plastic surgery operations. CONCLUSIONS Orthognathic surgery may rapidly be becoming a cosmetic procedure. This has the potential of creating a two-tier system whereby only those who can afford it will undergo orthognathic correction.
Collapse
|
7
|
Preventing the self-adherence of Mefix™. J Plast Reconstr Aesthet Surg 2007; 60:960. [PMID: 17616371 DOI: 10.1016/j.bjps.2006.07.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2006] [Accepted: 07/23/2006] [Indexed: 11/24/2022]
|
8
|
Warfarin versus aspirin in the elderly in primary prophylaxis for atrial fibrillation. Age Ageing 2007; 36:117-9. [PMID: 17255089 DOI: 10.1093/ageing/afl181] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
9
|
Comparing the cost of delayed and immediate autologous breast reconstruction in Belgium. ACTA ACUST UNITED AC 2005; 58:493-7. [PMID: 15897033 DOI: 10.1016/j.bjps.2004.12.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2004] [Accepted: 12/15/2004] [Indexed: 10/25/2022]
Abstract
This study documents the cost of immediate and delayed DIEP flap breast reconstruction. Immediate reconstruction is more attractive from an economic perspective since it only requires one operation, one anaesthetic procedure and one recovery period in hospital. From the perspective of healthcare budget management, assessing the possible cost savings from immediate reconstruction yields interesting results. Since charges do not reflect the real costs of providing care, we calculated resource costs using the micro-costing method. About 95% of the initial mastectomy costs could be saved when performing an immediate breast reconstruction. This was about 35% of total standard direct and indirect costs due to mastectomy and delayed breast reconstruction. In a growing cost conscious environment of managed care, the economic evaluation should, therefore, encourage the trend towards more immediate reconstructions.
Collapse
|
10
|
Missed injuries in the acutely traumatised hand. THE ULSTER MEDICAL JOURNAL 2003; 72:22-5. [PMID: 12868699 PMCID: PMC2475407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
A prospective study of 500 consecutive patients referred from accident and emergency departments in Northern Ireland with acute hand injuries was performed to assess the incidence of missed injuries. An injury was 'missed' if a patient was receiving inappropriate treatment or returned due to persistent symptoms despite being examined, treated and discharged. There were 16 (3.2%) missed injuries. Seven involved tendon only, four were isolated nerve injuries and four were mixed tendon and nerve injuries. The remaining case was a ruptured ulnar collateral ligament of the thumb metacarpophalangeal joint. Thirteen injuries were open, with a glass laceration being the most common mechanism of injury. The time to detection of a missed injury was on average 11 days (range 1-62 days). Missed hand injuries in Northern Ireland are uncommon but do occur. A thorough clinical examination and accurate injury documentation remain fundamental in their prevention.
Collapse
|
11
|
Abstract
Microsurgery and free tissue transfer play a vital role in the modern practice of reconstructive surgery. Prior to the advent of microsurgical free tissue transfer pedicle flaps were the workhorse of a reconstructive surgeon. We report a case of thumb reconstruction by pedicled transfer of the second toe with functional and aesthetic outcome. This case was performed in Pakistan where microsurgical facilities were not available.
Collapse
|
12
|
Nasal reconstruction using the Washio retroauricular temporal flap. BRITISH JOURNAL OF PLASTIC SURGERY 2003; 56:224-9. [PMID: 12859917 DOI: 10.1016/s0007-1226(03)00092-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Reconstruction of an external nasal defect presents a challenge to the reconstructive surgeon. Transferring retroauricular tissue on a temporal pedicle was first described by Washio as a means to repair the central portion of the face. This paper describes our experience with the Washio retroauricular temporal flap for nasal reconstruction in twelve patients, together with our modifications to simplify the planning and raising of the flap. There was one patient with a stitch abscess, one case of hair loss from the pedicle which recovered within one month and one elderly patient who developed thromboembolic complications. There was no instance of flap necrosis. Our results confirm that the Washio retroauricular flap is an excellent technique for difficult nasal reconstruction in young patients.
Collapse
|
13
|
Arterial reconstruction using the basilic vein from the zone of injury in pediatric supracondylar humeral fractures: a clinical and radiological series. Plast Reconstr Surg 2003; 111:1159-63; discussion 1164-6. [PMID: 12621186 DOI: 10.1097/01.prs.0000046608.52722.89] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The authors describe the advantages of using the basilic vein as an arterial conduit in the management of children with supracondylar humeral fractures requiring vascular repair. Eight children, aged 3 to 10 years, presented with supracondylar humeral fractures and vascular injury. In all eight children, the arteries were successfully reconstructed with a reversed, interposition basilic vein graft harvested from the ipsilateral arm. The basilic vein was anatomically consistent with few side branches and was an excellent size match for the brachial artery. There were no postoperative thromboses. At a minimum follow-up of 1 year, all children had palpable radial pulses and the vein grafts were patent with no anastomotic or other focal stenoses. This series confirms the safety of using a donor vein from within the zone of injury for arterial reconstruction, after a supracondylar humeral fracture. Benefits include a single surgical wound on the less conspicuous medial side of the arm, reduced operating time, and preservation of donor veins that may be subsequently required for the management of atherosclerotic disease.
Collapse
|
14
|
Pyoderma gangrensum--a complication of breast biopsy. THE ULSTER MEDICAL JOURNAL 2002; 71:66-7. [PMID: 12137170 PMCID: PMC2475350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
15
|
A novel member of the Ig superfamily, turtle, is a CNS-specific protein required for coordinated motor control. J Neurosci 2001; 21:3113-25. [PMID: 11312296 PMCID: PMC6762567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2000] [Revised: 01/29/2001] [Accepted: 02/22/2001] [Indexed: 02/19/2023] Open
Abstract
We describe here the cloning and functional characterization of a neural-specific novel member of the Ig superfamily, turtle (tutl), with a structure of five Ig C2-type domains, two fibronectin type III domains, and one transmembrane region. Alternative splicing of the tutl gene produces at least four Tutl isoforms, including two transmembrane proteins and two secreted proteins, with primary structures closely related to a human brain protein (KIAA1355), the Deleted in Colorectal Cancer/Neogenin/Frazzled receptor family, and the Roundabout/Dutt1 receptor family. An allelic series of tutl gene mutations resulted in recessive lethality to semilethality, indicating that the gene is essential. In contrast to other family members, tutl does not play a detectable role in axon pathfinding or nervous system morphogenesis. Likewise, basal synaptic transmission and locomotory movement are unaffected. However, tutl mutations cause striking movement defects exhibited in specific types of highly coordinated behavior. Specifically, tutl mutants display an abnormal response to tactile stimulation, the inability to regain an upright position from an inverted position (hence, "turtle"), and the inability to fly in adulthood. These phenotypes demonstrate that tutl plays an essential role in establishing a nervous system capable of executing coordinated motor output in complex behaviors.
Collapse
|
16
|
Abstract
The developmental stages of Oreochromis niloticus are similar to those described in other mouth-breeding tilapias except that, as in zebrafish, no cavity was found in the blastula. Variation in the rate of development of the embryo and larva of O. niloticus was found within a clutch of eggs as well as between clutches. Hatching glands are described for the first time in tilapias. They are widely distributed within the ectoderm covering the head, body, tail, and surface of the yolk sac near its attachment to the embryo. Timing of larval development is similar to that in other mouthbrooding tilapias, but is slower than that found in substrate-spawning tilapias. A pneumatic duct connects the swimbladder to the digestive tract and swimbladder inflation and initiation of feeding occurs at about the same time. The digestive tract of the larva 8 and 9 days after fertilization is similar to that found in the adult, except that there are no digestive glands. An endocrine pancreatic islet was first seen 76 h after fertilization. A prominent thymus gland is present at 100 h. Hematopoietic tissue develops in the vicinity of the pronephros during early larval development. A spleen develops later, 7 days after fertilization.
Collapse
|
17
|
Abstract
Age of acquisition (AoA) has been reported to be a predictor of the speed of reading words aloud (word naming) and lexical decision, with early-acquired words being responded to faster than later-acquired words in both tasks. All previous studies of AoA effects have, however, relied upon adult estimates of word learning age the validity of which it is easy to cast doubt upon. Using objective age of acquisition norms derived from children's naming data, this study shows that AoA effects do not depend upon the use of adult ratings. In addition to effects of real AoA, influences of word frequency and orthographic neighbourhood size were obtained in both word naming and lexical decision. Imageability affected lexical decision but not word naming, while the characteristics of the word's initial phoneme affected word naming but not lexical decision.
Collapse
|
18
|
Abstract
Streptozotocin (STZ) causes beta cell necrosis and insulin-dependent diabetes in many species. The specificity of this beta cell toxin relates to its structure as an alkylating agent with an attached glucose moiety. STZ uptake by rodent beta cells appears to be via the GLUT-2 glucose transporter. Teleost fish, in general, are severely glucose intolerant. The effects of STZ were examined in tilapia, a teleost fish with highly glucose-responsive islets. Fasted tilapia were given 0, 100, 150, 200, 250, 300, or 350 mg/kg STZ iv. Plasma glucose levels were followed for 72 h and the fish autopsied. Histological sections of islets were stained by immunoperoxidase for tilapia insulin. Severe hyperglycemia was seen in 20, 80, and 100% of fish receiving 250, 300, and 350 mg/kg doses; however, sections of islets showed only partial degranulation with no evidence of beta cell necrosis. Another group of fish receiving the highest dose were followed longer to determine whether beta cell necrosis and permanent hyperglycemia ensued. All fish died or were killed within 9 days because of severe hepatic failure characterized by hepatic necrosis, jaundice, and ascites; islet morphology was relatively normal suggesting, even in a glucose-sensitive species, that fish islets either do not take up STZ or are highly resistant to its "diabetogenic" effects. Tilapia may thus be a useful model to elucidate mechanisms of action of STZ. Furthermore, STZ may provide important insights into differences in glucose uptake and metabolism by mammalian and piscine beta cells.
Collapse
|
19
|
Immunocytochemical characterization of the pancreatic islet cells of the Nile Tilapia (Oreochromis niloticus). Gen Comp Endocrinol 1999; 114:47-56. [PMID: 10094858 DOI: 10.1006/gcen.1998.7234] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The cellular composition and topography of the pancreatic islet of Oreochromis niloticus, now known to be a donor source for islet xenotransplantation studies, were characterized. Whole tilapia islets were harvested using an enzymatic method and then further digested into single-cell preparations. Cell cytospin preparations of islet cells and paraffin sections of whole islets were stained using antisera against tilapia insulin, human glucagon, salmon somatostatin-25 (SST-25), human somatostatin-14 (SST-14), and salmon peptide tyrosine-tyrosine (PYY) using the immunoperoxidase method. Cell counts, performed on cytospin preparations using a Quantimet 570 computerized image analysis system, revealed that O. niloticus islets contained 78% endocrine cells and 22% immunonegative cells (i. e., mainly nucleated erythrocytes and rare tissue eosinophils). The proportions of immunopositive endocrine cell types were: 42.3% insulin immunopositive cells, 11.5% glucagon immunopositive cells, 23.1% SST-25 immunopositive cells, 21.8% SST-14 immunopositive cells, and 1.3% PYY immunopositive cells. Islet cell topography was evaluated using histologic sections of whole endocrine pancreata including large, medium, and small islets. Round to polygonal insulin immunopositive cells with round central nuclei were distributed in clusters throughout both the principal and the smaller islets. Elongate SST-14 immunopositive cells were closely associated with the clusters of insulin immunopositive cells; both were surrounded by SST-25 immunopositive cells, which were similar in shape to the insulin immunopositive cells. There were elongate glucagon immunopositive cells throughout the islets, whereas the PYY immunopositive cells were restricted to the periphery and to channels of fibrovascular connective tissue penetrating the islets.
Collapse
|
20
|
Abstract
Previous research on the effects of age of acquisition on lexical processing has relied on adult estimates of the age at which children learn words. The authors report 2 experiments in which effects of age of acquisition on lexical retrieval are demonstrated using real age-of-acquisition norms. In Experiment 1, real age of acquisition emerged as a powerful predictor of adult object-naming speed. There were also significant effects of visual complexity, word frequency, and name agreement. Similar results were obtained in reanalyses of data from 2 other studies of object naming. In Experiment 2, real age of acquisition affected immediate but not delayed object-naming speed. The authors conclude that age-of-acquisition effects are real and suggest that age of acquisition influences the speed with which spoken word forms can be retrieved from the phonological lexicon.
Collapse
|
21
|
Abstract
Previous research on the effects of age of acquisition on lexical processing has relied on adult estimates of the age at which children learn words. The authors report 2 experiments in which effects of age of acquisition on lexical retrieval are demonstrated using real age-of-acquisition norms. In Experiment 1, real age of acquisition emerged as a powerful predictor of adult object-naming speed. There were also significant effects of visual complexity, word frequency, and name agreement. Similar results were obtained in reanalyses of data from 2 other studies of object naming. In Experiment 2, real age of acquisition affected immediate but not delayed object-naming speed. The authors conclude that age-of-acquisition effects are real and suggest that age of acquisition influences the speed with which spoken word forms can be retrieved from the phonological lexicon.
Collapse
|
22
|
Initial experience with a electronic CT image transfer system. THE ULSTER MEDICAL JOURNAL 1994; 63:23-6. [PMID: 8658991 PMCID: PMC2449088] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
An electronic image transfer system for computed tomographic images links the CT scanner in Altnagelvin Hospital, Londonderry with the regional neuroradiology department in the Royal Victoria Hospital, Belfast. In the first 13 months of operation, scans of 100 patients were transferred; 49 scans were taken in acute neurosurgical emergencies, and 51 were non-acute sent for a specialist neuroradiological opinion. Potentially hazardous inter-hospital transfer was avoided in 21 cases of acute neurosurgical emergency, and more efficient and appropriate referral was achieved in the cases whose scans had been sent for sent for radiological second opinion. We believe that the system has substantially improved the diagnosis and management of patients with neurosurgical problems in both hospitals.
Collapse
|
23
|
Abstract
Male Sprague-Dawley rats were utilized to study the effects of the opioid receptor antagonists, naloxone and naltrexone, on thirst induced by thermal dehydration. In an initial experiment, the depressant effect of naloxone (1.0 mg/kg, IP) on the water intake of rats deprived of water for 24 h was confirmed. In subsequent experiments, rats were thermally dehydrated by exposing them without water to a 40 degrees C environment for 1-4 h. Following heat exposure, rats were injected with either naloxone or naltrexone either IP or ICV. Fifteen minutes later, rats were provided with water and water intake was measured for 2 h. Both naloxone and naltrexone had dose (0.1-5.0 mg/kg, IP)-dependent effects of reducing water intake of rats thermally dehydrated for 3 h. Water intake of rats thermally dehydrated for 2 or 4 h was also attenuated by pretreatment with naloxone. Rats thermally dehydrated for 3 h exhibited decreases in water intake following ICV injection of either naloxone or naltrexone at a dose of 50 micrograms. Neither naloxone nor naltrexone had an effect on urine output in any experiment. The water intake data support the hypothesis that thirst induced by thermal dehydration in rats is modulated by an opioid mechanism.
Collapse
|
24
|
Abstract
Word frequency is widely believed to affect object naming speed, despite several studies in which it has been reported that frequency effects may be redundant upon age of acquisition. We report, first, a reanalysis of data from the study by Oldfield and Wingfield (1965), which is standardly cited as evidence for a word frequency effect in object naming; then we report two new experiments. The reanalysis of Oldfield and Wingfield shows that age of acquisition is the major determinant of naming speed, and that frequency plays no independent role when its correlation with other variables is taken into account. In Experiment 1, age of acquisition and phoneme length proved to be the primary determinants of object naming speed. Frequency, prototypicality, and imageability had no independent effect. In Experiment 2, subjects classified objects into two semantic categories (natural or man-made). Prototypicality and semantic category were the only variables to have a significant effect on reaction time, with no effect of age of acquisition, frequency, imageability, or word length. We conclude that age of acquisition, not word frequency, affects the retrieval and/or execution of object names, not the process of object recognition. The locus of this effect is discussed, along with the possibility that words learned in early childhood may be more resistant to the effects of brain injury in at least some adult aphasics than words learned somewhat later.
Collapse
|
25
|
Morphology of diplomonad flagellates: Spironucleus torosa n. sp. from Atlantic cod Gadus morhua L., and haddock Melanogrammus aeglefinus (L.) and Hexamita salmonis Moore from brook trout Salvelinus fontinalis (Mitchill). THE JOURNAL OF PROTOZOOLOGY 1990; 37:369-83. [PMID: 2213651 DOI: 10.1111/j.1550-7408.1990.tb01160.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A diplomonad flagellate, Spironucleus torosa n. sp. is described from Atlantic Cod Gadus morhua and haddock Melanogrammus aeglefinus. This is believed to be the 1st confirmed report of Spironucleus from a marine fish. Organisms swimming in the rectal lumen were broadly pyriform to elongate, and measured 10.5-18.6 microns long and 3.2-13.3 microns wide; other elongate organisms were attached to the rectal epithelium, via apical extensions appearing continuous with the microvilli. The posterior end of the body was extended into a caudal projection, on either side of which was a posteriolateral ring-shaped protrusion or torus, with a recurrent flagellum emerging from its centre. A symmetrical system of microtubules and lamellae, forming a "V" in protargol impregnated specimens, supported the flanges of the body surrounding the tori, the tori themselves and the caudal projection. Supranuclear microtubules were an inverted V to U shape in transverse section, and an electron dense band accompanied the cytostomes. Lightly staining homogenous cytoplasm was usually present in the anterior part of the body, the remainder being highly vacuolated with numerous dark granules. In swimming organisms, rough endoplasmic reticulum (RER) was present around the nuclei and cytostomes, and bacteria were occasionally seen in the cytoplasm. In "attached" organisms, RER was reduced, and bacteria were absent. Hexamita salmonis Moore from Salvelinus fontinalis was studied by light and scanning electron microscopy for comparison; its cytoplasm was not highly vacuolated. The two recurrent flagella emerged close together from the blunt posterior end of the body.
Collapse
|
26
|
Abstract
The genes encoding the structural components of nitrogenase, nifH, nifD and nifK, from the fast-growing, broad-host-range Rhizobium strain ANU240 have been identified and characterized. They are duplicated and linked in an operon nifHDK in both copies. Sequence analysis of the nifH gene from each copy, together with partial sequence analysis of the nifD and nifK genes, and restriction endonuclease analysis suggested that the duplication is precise. Comparison of the Fe-protein sequence from strain ANU240 with that from other nitrogen-fixing organisms revealed that, despite its broad host range and certain physiological properties characteristic of Bradyrhizobium strains, ANU240 is more closely related to the narrow-host-range Rhizobium strains than to the broad-host-range Bradyrhizobium strains. The promoter regions of both copies of the nif genes contain the consensus sequence characteristic of nif promoters, and functional analysis of the two promoters suggested that both nif operons are transcribed in nodules.
Collapse
|
27
|
The fine structure of the ventricular surface of the area postrema of the cat, with particular reference to supraependymal structures. THE AMERICAN JOURNAL OF ANATOMY 1978; 153:273-90. [PMID: 707317 DOI: 10.1002/aja.1001530207] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The ependymal surface of the feline area postrema (AP) has been examined with the scanning and transmission electron microscopes. Particular attention was paid to the distribution and structure of supraependymal (SE) cells which have not been described before on this organ. A population of SE cells was found consistently on the cat AP; they were grouped most frequently toward the caudal aspect of the organ. Their structure bears a great resemblance to that of macrophages, containing: (1) many small apical vacuoles, (2) numerous lysosomes, and (3) phagosome-like bodies. Arrays of microvillous tufts and also singly-occurring microvilli are features of the unciliated ependymal surface of the organ. Tufts are often found in very close proximity to superficial blood vessels which are characteristically surrounded by large perivascular spaces.
Collapse
|
28
|
|