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Response to Shtarbanov et al paper: Raising of bi-pedicled flaps increases operative time and complications. J Plast Reconstr Aesthet Surg 2024; 88:243-244. [PMID: 38007996 DOI: 10.1016/j.bjps.2023.10.057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 10/07/2023] [Indexed: 11/28/2023]
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Development of a pediatric obstructive sleep apnea triage algorithm. J Otolaryngol Head Neck Surg 2021; 50:48. [PMID: 34266488 PMCID: PMC8281470 DOI: 10.1186/s40463-021-00528-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 06/14/2021] [Indexed: 02/07/2023] Open
Abstract
INTRODUCTION Diagnosis and treatment of obstructive sleep apnea (OSA) in children is often delayed due to the high prevalence and limited physician and sleep testing resources. As a result, children may be referred to multiple specialties, such as pediatric sleep medicine and pediatric otolaryngology, resulting in long waitlists. METHOD We used data from our pediatric OSA clinic to identify predictors of tonsillectomy and/or adenoidectomy (AT). Before being seen in the clinic, parents completed the Pediatric Sleep Questionnaire (PSQ) and screening questionnaires for restless leg syndrome (RLS), nasal rhinitis, and gastroesophageal reflux disease (GERD). Tonsil size data were obtained from patient charts and graded using the Brodsky-five grade scale. Children completed an overnight oximetry study before being seen in the clinic, and a McGill oximetry score (MOS) was assigned based on the number and depth of oxygen desaturations. Logistic regression, controlling for otolaryngology physician, was used to identify significant predictors of AT. Three triage algorithms were subsequently generated based on the univariate and multivariate results to predict AT. RESULTS From the OSA cohort, there were 469 eligible children (47% female, mean age = 8.19 years, SD = 3.59), with 89% of children reported snoring. Significant predictors of AT in univariate analysis included tonsil size and four PSQ questions, (1) struggles to breathe at night, (2) apneas, (3) daytime mouth breathing, and (4) AM dry mouth. The first triage algorithm, only using the four PSQ questions, had an odds ratio (OR) of 4.02 for predicting AT (sensitivity = 0.28, specificity = 0.91). Using only tonsil size, the second algorithm had an OR to predict AT of 9.11 (sensitivity = 0.72, specificity = 0.78). The third algorithm, where MOS was used to stratify risk for AT among those children with 2+ tonsils, had the same OR, sensitivity, and specificity as the tonsil-only algorithm. CONCLUSION Tonsil size was the strongest predictor of AT, while oximetry helped stratify individual risk for AT. We recommend that referral letters for snoring children include graded tonsil size to aid in the triage based on our findings. Children with 2+ tonsil sizes should be triaged to otolaryngology, while the remainder should be referred to a pediatric sleep specialist.
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Role of MRI in Scaphoid Injuries: The Scaphoid Magnetic Resonance Imaging in Trauma (SMaRT) Trial. Semin Musculoskelet Radiol 2019. [DOI: 10.1055/s-0039-1692553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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A Tale of Twos: Dual-energy CT, an Indispensable Metal Artifact Reduction Tool Around Implants: A Multi-center Experience from Two Primary and Revision Hip Arthroplasty Units. Semin Musculoskelet Radiol 2019. [DOI: 10.1055/s-0039-1692581] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Critical care usage after major gastrointestinal and liver surgery: a prospective, multicentre observational study. Br J Anaesth 2019; 122:42-50. [PMID: 30579405 DOI: 10.1016/j.bja.2018.07.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Revised: 07/19/2018] [Accepted: 07/23/2018] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Patient selection for critical care admission must balance patient safety with optimal resource allocation. This study aimed to determine the relationship between critical care admission, and postoperative mortality after abdominal surgery. METHODS This prespecified secondary analysis of a multicentre, prospective, observational study included consecutive patients enrolled in the DISCOVER study from UK and Republic of Ireland undergoing major gastrointestinal and liver surgery between October and December 2014. The primary outcome was 30-day mortality. Multivariate logistic regression was used to explore associations between critical care admission (planned and unplanned) and mortality, and inter-centre variation in critical care admission after emergency laparotomy. RESULTS Of 4529 patients included, 37.8% (n=1713) underwent planned critical care admissions from theatre. Some 3.1% (n=86/2816) admitted to ward-level care subsequently underwent unplanned critical care admission. Overall 30-day mortality was 2.9% (n=133/4519), and the risk-adjusted association between 30-day mortality and critical care admission was higher in unplanned [odds ratio (OR): 8.65, 95% confidence interval (CI): 3.51-19.97) than planned admissions (OR: 2.32, 95% CI: 1.43-3.85). Some 26.7% of patients (n=1210/4529) underwent emergency laparotomies. After adjustment, 49.3% (95% CI: 46.8-51.9%, P<0.001) were predicted to have planned critical care admissions, with 7% (n=10/145) of centres outside the 95% CI. CONCLUSIONS After risk adjustment, no 30-day survival benefit was identified for either planned or unplanned postoperative admissions to critical care within this cohort. This likely represents appropriate admission of the highest-risk patients. Planned admissions in selected, intermediate-risk patients may present a strategy to mitigate the risk of unplanned admission. Substantial inter-centre variation exists in planned critical care admissions after emergency laparotomies.
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Correlation between gonial angle and dynamic tongue collapse in children with snoring/sleep disordered breathing - an exploratory pilot study. J Otolaryngol Head Neck Surg 2018; 47:41. [PMID: 29866168 PMCID: PMC5987664 DOI: 10.1186/s40463-018-0285-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 05/20/2018] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Drug induced sleep endoscopy (DISE) is hoped to identify reasons of failure of adenotonsillectomy (AT) in treating pediatric sleep disordered breathing (SDB). Maxillomandibular disproportion has been studied as another association which may explain alternative pathogenesis of SDB. We aimed to explore the relation between the size of the gonial angle and inclination of the epiglottis measured from cone beam CT (CBCT) and tongue base collapse based on DISE in children with SDB. METHOD A retrospective chart review was conducted at a tertiary pediatric center. Children (6-17 years old) assessed at a multi-disciplinary Upper Airway Clinic, diagnosed with SDB and maxillo-mandibular disproportion (MMD), and who underwent DISE were eligible. Variables obtained from the electronic medical records of the clinic and prospective database included demographics, comorbidities, surgeries performed, investigations, DISE findings and CBCT findings. The gonial angle of subjects with and without tongue base collapse (TBC) on SNP were compared. RESULTS In total 29 patients (13 male, 8 female) age 6-17 (median= 9) were eligible for the study from January 2009 - July 2016. We included 11 subjects, and 10 comparators. The mean gonial angle of the TBC group was 139.3°± 7.6°, while that of the comparison group was 129.4°±3.5 (mean difference -9.937, 95% CI of -15.454 to - 4.421, P = 0.001, power of test 0.95). Additionally, the mean inclination of the epiglottis had a mild positive correlation (r=0.32, p<0.05) with the gonial angle, in the whole cohort. CONCLUSIONS This pilot study suggests that TBC may be mediated by a wider gonial angle in children with SDB patients. The posterior tilt of the epiglottis on CBCT may be a surrogate sign of TBC.
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Novel Semiquantitative Bone Marrow Oedema Score and Fracture Score for the Magnetic Resonance Imaging Assessment of the Active Charcot Foot in Diabetes. J Diabetes Res 2017; 2017:8504137. [PMID: 29230422 PMCID: PMC5694565 DOI: 10.1155/2017/8504137] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Revised: 08/04/2017] [Accepted: 08/13/2017] [Indexed: 11/17/2022] Open
Abstract
There are no accepted methods to grade bone marrow oedema (BMO) and fracture on magnetic resonance imaging (MRI) scans in Charcot osteoarthropathy. The aim was to devise semiquantitative BMO and fracture scores on foot and ankle MRI scans in diabetic patients with active osteoarthropathy and to assess the agreement in using these scores. Three radiologists assessed 45 scans (Siemens Avanto 1.5T, dedicated foot and ankle coil) and scored independently twenty-two bones (proximal phalanges, medial and lateral sesamoids, metatarsals, tarsals, distal tibial plafond, and medial and lateral malleoli) for BMO (0-no oedema, 1-oedema < 50% of bone volume, and 2-oedema > 50% of bone volume) and fracture (0-no fracture, 1-fracture, and 2-collapse/fragmentation). Interobserver agreement and intraobserver agreement were measured using multilevel modelling and intraclass correlation (ICC). The interobserver agreement for the total BMO and fracture scores was very good (ICC = 0.83, 95% confidence intervals (CI) 0.76, 0.91) and good (ICC = 0.62; 95% CI 0.48, 0.76), respectively. The intraobserver agreement for the total BMO and fracture scores was good (ICC = 0.78, 95% CI 0.6, 0.95) and fair to moderate (ICC = 0.44; 95% CI 0.14, 0.74), respectively. The proposed BMO and fracture scores are reliable and can be used to grade the extent of bone damage in the active Charcot foot.
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The 10 key steps for radiographic analysis of adolescent idiopathic scoliosis. Clin Radiol 2015; 70:235-42. [DOI: 10.1016/j.crad.2014.11.013] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2013] [Accepted: 11/19/2014] [Indexed: 11/16/2022]
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Tibial cortical lesions: a multimodality pictorial review. Eur J Radiol 2014; 84:123-141. [PMID: 25445894 DOI: 10.1016/j.ejrad.2014.09.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Revised: 07/01/2014] [Accepted: 09/09/2014] [Indexed: 11/29/2022]
Abstract
Shin pain is a common complaint, particularly in young and active patients, with a wide range of potential diagnoses and resulting implications. We review the natural history and multimodality imaging findings of the more common causes of cortically-based tibial lesions, as well as the rarer pathologies less frequently encountered in a general radiology department.
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Three invasive species occurring in the diets of fishes in a Neotropical floodplain. BRAZ J BIOL 2014; 74:S16-22. [DOI: 10.1590/1519-6984.18312] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2012] [Accepted: 07/31/2013] [Indexed: 11/22/2022] Open
Abstract
The composition of the diets of 66 species of fishes was investigated from September 2009 to June 2010 in three subsystems of the Upper Paraná River floodplain (Brazil), following invasion by the two mollusk species Limnoperna fortunei (Dunker, 1857) and Corbicula fluminea (Müller, 1774), and the macrophyte Hydrilla verticillata (L.f.) Royle. Limnoperna fortunei was consumed in all three subsystems and occurred in the diet of 15 fish species, with a high proportion in the diet of Leporinus obtusidens. Corbicula flumineawas present in the diet of Pterodoras granulosus caught in the Paraná and Ivinheima subsystems. Hydrilla verticillataoccurred in the diet of Schizodon nasutus caught in the Ivinheima and Paraná subsystems. It is not yet possible to evaluate the potential of these species to control invasive mollusks in the study area or the impact of these species on the structure of the food chain. Omnivorous and herbivorous fishes in the study area may have little impact on the population of H. verticillata.
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Trends of C-Reactive Protein Laboratory Values With White Blood Cell Count Levels in Maxillofacial Infections. J Oral Maxillofac Surg 2013. [DOI: 10.1016/j.joms.2013.06.055] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Interprofessional relationships between orthopaedic and podiatric surgeons in the UK. Ann R Coll Surg Engl 2008; 90:663-70. [PMID: 18796189 DOI: 10.1308/003588408x318183] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION The first comprehensive report on the interprofessional relationships between foot and ankle surgeons in the UK is presented. MATERIALS AND METHODS A questionnaire was sent to orthopaedic surgeons with membership of the British Foot and Ankle Surgery Society (BOFAS), orthopaedic surgeons not affiliated to the specialist BOFAS and podiatrists specialising in foot surgery. The questionnaire was returned by 77 (49%) of the BOFAS orthopaedic consultant surgeons, 66 (26%) of non-foot and ankle orthopaedic consultant surgeons and 99 (73%) of the podiatric surgeons. RESULTS While most respondents have experience of surgeons working in the other specialty in close geographical proximity, the majority do not believe that this has adversely affected their referral base. The experience of podiatrists of the outcomes of orthopaedic surgery has been more positive than orthopaedic surgeons of podiatric interventions. Podiatrists are more welcoming of future orthopaedic involvement in future foot and ankle services than in reverse. However, there are a sizeable number of surgeons in both professions who would like to see closer professional liaisons. The study has identified clear divisions between the professions but has highlighted areas where there is a desire from many clinicians to work more harmoniously together, such as in education, training and research. CONCLUSIONS While major concerns exist over issues such as surgery by non-registered medical practitioners and the suitable spectrum of surgery for each profession, many surgeons, in both professions, are willing to provide training for juniors in both specialties and there is a wish to have closer working relationships and common educational and research opportunities than exists at present.
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Endoparasite infracommunities of Hemisorubim platyrhynchos (Valenciennes, 1840) (Pisces: Pimelodidae) of the Baía River, upper Paraná River floodplain, Brazil: specific composition and ecological aspects. BRAZ J BIOL 2003; 63:261-8. [PMID: 14509848 DOI: 10.1590/s1519-69842003000200011] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Parasites of 136 specimens of Hemisorubim platyrhynchos, popularly called jurupoca, were analyzed. Fourteen parasite species were recorded: four digeneans (Crocodilicola pseudostoma, one Gorgoderidae species, Sanguinicola platyrhynchi, and Sphincterodiplostomum sp.); three cestodes (Goezeella paranaensis, Spatulifer maringaensis, and Mariauxiella piscatorum); five nematodes (Contracaecum Type 1 larvae of Moravec, Kohn, & Fernandes, 1993; Contracaecum Type 2 larvae of Moravec, Kohn, & Fernandes, 1993; Cucullanus (Cucullanus) zungaro; Eustrongylides ignotus; and Goezia sp.); one acanthocephalan (Quadrigyrus machadoi), and one pentastomid (Sebekia sp.). Most of the helminth specimens were found in larval stages, confirming that H. platyrhynchos is a significant source of their transmission. No dominance was reported. With the exception of Contracaecum Type 2 (featuring random dispersion), the species had a clumped pattern of dispersion in the host sample. Evidence of competition among parasite species was not reported. Several species of parasites were correlated with host size and sex. This fact may be explained by increase in food content and possible behavioral modifications of male and female hosts. Infracommunity diversity was not related to host size or sex.
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A young man with sore throat, acute abdomen and respiratory failure. J Postgrad Med 2003; 49:166-8. [PMID: 12867697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/03/2023] Open
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Sanguinicola platyrhynchi n. sp. (Digenea: Sanguinicolidae) parasite of visceral cavity of Hemisorubim platyrhynchos (Valenciennes, 1840) (Pisces: Pimelodidae) from the floodplain of the upper Paraná River, Brazil. BRAZ J BIOL 2002; 62:801-6. [PMID: 12659031 DOI: 10.1590/s1519-69842002000500009] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A new species is of the genus Sanguinicola Plehn, 1905 described, Sanguinicola platyrhynchi n. sp., digenetic parasite of visceral cavity of Hemisorubim platyrhynchos (Valenciennes, 1840) from the floodplain of the upper Paraná River, Brazil. The species has been thus included because of the presence of separate dorsal genital pores, while differing from other species of the same genus mainly in digestive apparatus features, genital pore position, and infection site. Emendation of generic diagnosis is included.
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The role of A1/A3 adenosine receptor activation in reduction of cardiomyocyte injury caused by hypoxic stress and in induction of apoptosis in rat cardiomyocyte cultures. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2002; 486:201-5. [PMID: 11783485 DOI: 10.1007/0-306-46843-3_41] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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Gene interference using antisense oligodeoxynucleotides on whole chick embryos. Optimal ring and roller-bottle culture technique. Mol Biotechnol 2000; 15:259-77. [PMID: 10986702 DOI: 10.1385/mb:15:3:259] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Details are given of an advanced version of the ring method of chick embryo culture. This ensures good development from early blastoderm stages even when the culturing procedure is interrupted by the extended periods required for collecting matched embryo samples and for preparing antisense treatment. Antisense oligodeoxynucleotide treatment, in short-term incubation before return of blastoderms to their ring cultures, is then described. An alternative, roller-bottle, culture method for continued development after treatment is also described. Criteria for the validity and success of this gene interference method are given. While the text is meant to be of detailed practical help to those inexperienced in embryo culture, a preliminary reading, and familiarity with its sectional (Subheading) structure, is recommended before work is undertaken.
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Induction of apoptosis in rat cardiocytes by A3 adenosine receptor activation and its suppression by isoproterenol. Exp Cell Res 2000; 257:111-26. [PMID: 10854059 PMCID: PMC10792615 DOI: 10.1006/excr.2000.4882] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The purpose of the present study was to investigate the mechanisms involved in the induction of apoptosis in newborn cultured cardiomyocytes by activation of adenosine (ADO) A3 receptors and to examine the protective effects of beta-adrenoceptors. The selective agonist for A3 ADO receptors Cl-IB-MECA (2-chloro-N6-iodobenzyl-5-N-methylcarboxamidoadenosine) and the antagonist MRS1523 (5-propyl-2-ethyl-4-propyl-3-(ethylsulfanylcarbonyl)-6-phenylpy rid ine-5-carboxylate) were used. High concentrations of the Cl-IB-MECA (> or = 10 microM) agonist induced morphological modifications of myogenic cells, such as rounding and retraction of cell body and dissolution of contractile filaments, followed by apoptotic death. In addition, Cl-IB-MECA caused a sustained and reversible increase in [Ca2+]i, which was prevented by the selective antagonist MRS1523. Furthermore, MRS1523 protected the cardiocytes if briefly exposed to Cl-IB-MECA and partially protected from prolonged (48 h) agonist exposure. Apoptosis induced by Cl-IB-MECA was not redox-dependent, since the mitochondrial membrane potential remained constant until the terminal stage of cell death. Cl-IB-MECA activated caspase-3 protease in a concentration-dependent manner after 7 h of treatment and more effectively after 18 h of exposure. Bcl-2 protein was readily detected in control cells, and its expression was significantly decreased after 24 and 48 h of treatment with Cl-IB-MECA. Beta-adrenergic stimulation antagonized the pro-apoptotic effects of Cl-IB-MECA, probably through a cAMP/protein kinase A-independent mechanism, since addition of dibutyryl-cAMP did not abolish the apoptosis induced by Cl-IB-MECA. Incubation of cultured myocytes with isoproterenol (5 microM) for 3 or 24 h almost completely abolished the increase in [Ca2+]i. Prolonged incubation of cardiomyocytes with isoproterenol and Cl-IB-MECA did not induce apoptosis. Our data suggest that the apoptosis-inducing signal from activation of adenosine A3 receptors (or counteracting beta-adrenergic signal) leads to the activation of the G-protein-coupled enzymes and downstream pathways to a self-amplifying cascade. Expression of different genes within this cascade is responsible for orchestrating either cardiomyocyte apoptosis or its protection.
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Abstract
SnR, twist and Fgf10 are expressed in presumptive limb territories of early chick embryos. When FGF-2/FGF-8 beads are implanted in chick flank, an ectopic limb develops and SnR is irreversibly activated as early as 1 h. Ectopic Fgf10 and twist expression are activated much later at 17 and 20 h, respectively. FGF-10 can also induce SnR, but much later, and in this case activation occurs simultaneously with that of twist and Fgf10 via the Fgf8- expressing ridge. Tbx-4 and Tbx-5 are expressed in leg and wing forming regions, respectively, in a similar pattern to SnR and twist. FGF-2 leads to ectopic expression of Tbx-4 and Tbx-5 as rapidly as ectopic expression of SnR, but the patterns of ectopic transcripts suggest that induction of SnR and Tbx gene expression occur via different pathways.
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Photorefractive keratectomy for correction of epikeratophakia regression. ARCHIVES OF OPHTHALMOLOGY (CHICAGO, ILL. : 1960) 2000; 118:281-2. [PMID: 10676798 DOI: 10.1001/archopht.118.2.281] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Flik, a chick follistatin-related gene, functions in gastrular dorsalisation/neural induction and in subsequent maintenance of midline Sonic hedgehog signalling. Dev Biol 1999; 214:298-317. [PMID: 10525336 DOI: 10.1006/dbio.1999.9421] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have targetted the chick gene Flik with antisense oligodeoxynucleotide treatment at gastrular stages, when it is expressed in organiser-derived structures of the midline (K. Patel et al., 1996, Dev. Biol. 178, 327-342). A specific syndrome of deficient axial patterning and holoprosencephaly is produced. Most aspects of this syndrome can be understood as due to attenuation of dorsalising and neural-inducing signals during gastrulation, followed by failure to maintain the later signals from chordamesoderm/neural midline that pattern the mesodermal and neural cross sections during subsequent stages. Anatomical effects are first apparent at early neurula stages and correspond with what might be expected from a reduced counteraction of the ventralising Bone morphogenetic protein (BMP) pathway at the earlier stages, coupled with inadequate Sonic hedgehog (Shh) signalling subsequently. Delay in the clearing of BMP-4 RNA expression from the presumptive neural region at gastrulation is indeed seen, though chordin RNA expression within organiser derivatives remains normal. Subsequently, specific attenuation of chordamesoderm and neural midline Shh expression is observed. Brief preincubation of stage 4 chick blastoderms in supernatant from Xenopus oocytes that have been injected with Flik RNA prolongs and enhances the competence of their peripheral epiblast to respond to neural inductive signals from grafted Hensen's nodes. This effect specifically mimics that recently observed using microg/ml solutions of recombinant Follistatin (D. J. Connolly et al., 1999, Int. J. Dev. Biol., in press), further suggesting that Flik protein might act in vivo by somehow modulating activity of signalling pathways through BMP or other TGFbeta-related ligands. We discuss the significance of the observations in relation to recent ideas about neural induction, about possible redundancy in gene action, and about subsequent patterning of the axial cross section, suggesting that a Flik function in autocrine/paracrine maintenance of later midline Shh signalling represents a role of the gene separate from that in primary dorsalisation/neural induction.
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Gene interference using antisense oligodeoxynucleotides on whole chick embryos. Optimal ring and roller-bottle culture technique. Methods Mol Biol 1999; 97:673-97. [PMID: 10443403 DOI: 10.1385/1-59259-270-8:673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
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Nodal signalling and the roles of the transcription factors SnR and Pitx2 in vertebrate left-right asymmetry. Curr Biol 1999; 9:609-12. [PMID: 10359698 DOI: 10.1016/s0960-9822(99)80267-x] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Left-specific mesodermal expression of the homeobox gene Pitx2 links a gastrula-stage intercellular signalling cascade to the later development of vertebrate left-right organ asymmetry through the Nodal signalling pathway [1] [2][3] [4][5] [6]. SnR (Drosophila snail-related), a gene conserved in vertebrates and encoding a zinc-finger protein, appears to function in a similar manner to Pitx2, but through right-specific mesodermal expression [7] [8]. Here, we present direct evidence for an earlier proposal [7] that Nodal signalling specifically represses expression of SnR in left lateral mesoderm, and thus ensures its normal confinement to the right, while activating Pitx2 on the left. We addressed the relationship between Pitx2 and SnR using antisense disruption of SnR. Relatively severe antisense-SnR treatment led to massive ectopic expression of Pitx2 on the right, accompanied by randomisation of situs with embryos showing aspects of left-cardiac isomerism. This indicates a gene cascade relationship in the propagation of left-right information, whereby nodal activates Pitx2 on the left through a double-negative mechanism involving the repression of SnR's repressor role on Pitx2. Milder antisense-SnR treatment reversed heart-loop direction and embryo torsion at significant incidence, although Pitx2 expression remained normally left-confined throughout. This reversed morphology following SnR disruption alone appeared different from that in which additional ectopic right-hand Pitx2 expression was seen. Therefore, in addition to their regulatory gene cascade relationship, these two transcription factors appear to have further, parallel but non-redundant, roles in directly controlling normally right- and left-specific morphogenetic processes.
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Abstract
Mll, Brg1 and Brm are vertebrate homologues of Drosophila trithorax group (trxG) genes. We isolated chicken Mll cDNA clones, and examined patterns of Mll, Brg1 and Brm expression in chick embryos. All three genes were expressed from embryonic stage 2 onwards. Mll transcripts were just detectable in all tissues by in situ hybridization, with highest level in dorsal neural tube and notochord. Brg1 transcripts were readily detectable in all tissues, with highest levels in dorsal neural tube, dorsal trunk epithelium and limb bud epithelium and mesenchyme. Brm transcripts were more restricted, being found in dermomyotome, notochord, dorsal limb bud epithelium, eye and the roof and floor plates of the neural tube.
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Abstract
Lateralized looping of the heart tube, with associated torsion of the embryo axis, is the first structural sign of the consistent left-right asymmetrical organization that characterizes all vertebrate embryos. Rare failures or reversals of this asymmetry in humans lead to clinically important syndromes of malformation in heart and great blood vessels. Recently, elements of the genetic control sequence underlying this left-right aspect of development have been uncovered. The normal sequence of transmission for asymmetry information can now be traced to a point close to the actual execution of right-hand looping in the heart tube, with the hope that the further sequence of gene activity, within the heart itself and directing these events, may soon be uncovered.
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Abstract
Tbx-2, Tbx-3, Tbx-4 and Tbx-5 chick genes have been isolated and, like the mouse homologues, are expressed in the limb regions. Tbx-2 and Tbx-3 are expressed in anterior and posterior domains in wings and legs, as well as throughout the flank. Of particular interest, however, are Tbx-5, which is expressed in wing and flank but not leg, and Tbx-4, which is expressed very strongly in leg but not wing. Grafts of leg tissue to wing and wing tissue to leg give rise to toe-like or wing-like digits in wing and leg respectively. Expression of Tbx-4 is stable when leg tissue is grafted to wing, and Tbx-5 expression is stable when wing tissue is grafted to leg. Induction of either extra wings or legs from the flank by applying FGF-2 in different positions alters the expression of Tbx-4 and Tbx-5 in such a way that suggests that the amount of Tbx-4 that is expressed in the limb determines the type that will form. The ectopic limb always displays a limb-like Tbx-3 expression. Thus Tbx-4 and Tbx-5 are strong candidates for encoding ‘wingness’ and ‘legness’.
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Abstract
A gene encoding a zinc finger protein of the Snail family, cSnR, is expressed in the right-hand lateral mesoderm during normal chick development. Antisense disruption of cSnR function during the hours immediately preceding heart formation randomized the normally reliable direction of heart looping and subsequent embryo torsion. Implanted ectopic sources of intercellular signal proteins that are involved in establishing normal left-right information randomized the handedness of heart development and also altered the asymmetry of cSnR expression. cSnR thus appears to act downstream of these signals, or perhaps in parallel with the latest expressed of them, the Nodal protein, in controlling the anatomical asymmetry.
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Acute ethanol consumption synergizes with trauma to increase monocyte tumor necrosis factor alpha production late postinjury. J Clin Immunol 1994; 14:340-52. [PMID: 7883861 DOI: 10.1007/bf01546318] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The hypothesis that acute ethanol uptake plus trauma can synergize to increase immunosuppression was tested. We found that, unlike non-alcohol-exposed patients, patients with acute alcohol use prior to trauma have a transient decrease in monocyte tumor necrosis factor alpha (TNF alpha) production during the very early postinjury (0-3 days) period. However, TNF alpha production by these alcohol-exposed patients' monocytes (M0) became hyperelevated late postinjury (> 9 days). Consequently, these massively elevated M0 TNF alpha levels can contribute to posttrauma immunosuppression after acute alcohol use. We also demonstrate that normal monocyte activation with the superantigen, Staphylococcus enterotoxin B (SEB), results in a preferential induction of cell-associated M0 TNF alpha production, described as characteristic of immunosuppressed trauma patients. Acute in vitro ethanol treatment down-regulated the elevated TNF alpha production by trauma patients' M0 after either SEB, muramyl-dipeptide (MDP), interferon-gamma plus MDP, or lipopolysaccharide (LPS) stimulation. Both SEB- and LPS-induced TNF alpha mRNA induction was inhibited by acute alcohol treatment in normal M0, indicating that ethanol can regulate cytokine gene expression. An additional immunosuppressive effect of acute ethanol's stimulation was suggested by its induction of elevated transforming growth factor beta production in trauma patients' activated M0.
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Abstract
The authors administered a gaze discrimination task to 24 patients with chronic schizophrenia and 25 subjects with no psychiatric history. Each subject was shown slides and asked, "Is the person in the slide looking directly at you?" Patients with schizophrenia were more likely than comparison subjects to perceive the person in the slide as looking at them when the person was looking away. Because there is evidence that gaze discrimination performance involves the superior temporal sulcus region of the brain and this region has been implicated in theories about the pathogenesis of schizophrenia, further study of the gaze discrimination task seems indicated.
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Immunotherapeutic modulation of intraperitoneal adhesions by Asparagus racemosus. J Postgrad Med 1989; 35:199-203. [PMID: 2641519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The hypothesis that macrophages appear to play a pivotal role in the development of intraperitoneal adhesions and that modulation of macrophage activity, therefore, is likely to provide a tool for prevention of adhesions, was tested in the present study. Effect of Asparagus racemosus, an indigenous agent with immunostimulant properties, was evaluated in an animal model of intraperitoneal adhesions induced by caecal rubbing. Animals were sacrificed 15 days following surgery. The peritoneal macrophages were collected to assess their activity. At the same time, peritoneal cavity was examined for the presence of adhesions, which were graded. A significant decrease was observed in the adhesion scores attained by animals receiving Asparagus racemosus. This was associated with significant increase in the activity of macrophages (70.1 +/- 2.52), compared to that in surgical controls (53.77 +/- 10.8). These findings support our hypothesis and provide a novel approach for the prevention and management of post-operative adhesions.
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