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McPhee M, Arumainayagam N, Clark M, Burfitt N, DasGupta R. Renal injury management in an urban trauma centre and implications for urological training. Ann R Coll Surg Engl 2015; 97:194-7. [PMID: 26263803 DOI: 10.1308/003588414x14055925061117] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
INTRODUCTION The aim of this study was to analyse the treatment and management of renal injury patients presenting to our major trauma unit to determine the likelihood of patients needing immediate nephrectomy. METHODS The Trauma Audit and Research Network (TARN) database was used to review trauma cases presenting to our department between February 2009 and September 2013. Demographic data, mechanism and severity of injury, grade of renal trauma, management and 30-day outcome were determined from TARN data, electronic patient records and imaging. RESULTS There were a total of 1,856 trauma cases, of which 36 patients (1.9%) had a renal injury. In this group, the median age was 28 years (range: 16-92 years), with 28 patients (78%) having blunt renal trauma and 8 (22%) penetrating renal trauma. The most common cause for blunt renal trauma was road traffic accidents. Renal trauma cases were stratified into American Association for the Surgery of Trauma (AAST) grades (grade I: 19%, grade II: 22%, grade III: 28%, grade IV: 28%, grade V: 0%). All patients with grade I and II injuries were treated conservatively. There were three patients (1 with grade III and 2 with grade IV renal injuries) who underwent radiological embolisation. One of these patients went on to have a delayed nephrectomy owing to unsuccessful embolisation. CONCLUSIONS Trauma patients rarely require emergency nephrectomy. Radiological selective embolisation provides a good interventional option in cases of active bleeding from renal injury in haemodynamically stable patients. This has implications for trauma care and how surgical cover is provided for the rare event of nephrectomy.
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Affiliation(s)
| | | | - M Clark
- Imperial College Healthcare NHS Trust , UK
| | - N Burfitt
- Imperial College Healthcare NHS Trust , UK
| | - R DasGupta
- Imperial College Healthcare NHS Trust , UK
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Abstract
OBJECTIVE To estimate the cost-effectiveness of pramipexole versus no treatment and ropinirole in moderate to very severe idiopathic restless legs syndrome (RLS) in the UK and Sweden. METHODS A Markov model was developed using clinical trial data for pramipexole and ropinirole. Model health states were based on the International RLS Study Group Rating Scale (IRLS) scores. Health states were: no (IRLS 0), mild (IRLS 1-14), moderate (IRLS 15-24), severe (IRLS 25-34), very severe RLS (IRLS 35-40) and death. Patients entered the model with an IRLS score > 15 matching the trial inclusion criteria of the pramipexole trials. Resource use and utilities were based on trial data, literature, a patient survey and a panel of physicians from the UK and Sweden in the absence of published information. A healthcare sector perspective was taken for the UK and a societal perspective for Sweden using 2004-2005 unit costs. The base case analysis took a 1-year timeframe. RESULTS In the UK the incremental cost per quality-adjusted life year (QALY) for pramipexole was 3349 pounds sterling versus no treatment and a cost-saving of 92 pounds sterling against ropinirole. In Sweden, pramipexole produced cost-savings of Swedish Krona (SEK) 2381 (176 pounds sterling) versus no treatment and SEK 3564 (264 pounds sterling) against ropinirole. QALY gains in both countries were 0.095 versus no treatment and 0.007 versus ropinirole. Results compare well with UK cost-effectiveness thresholds of 20,000 pounds sterling/30,000 pounds sterling per QALY and are cost-saving for Sweden. One-way and probabilistic sensitivity analyses showed results to be robust. CONCLUSIONS Pramipexole is cost-effective compared to no treatment and ropinirole for patients with moderate to very severe RLS.
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Affiliation(s)
- M Lees
- Oxford Outcomes Ltd, Oxford, UK
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Kanabar G, DasGupta R, Fowler C. Pudendal somatosensory evoked potential (SSEP) and quantitative sensory testing (QST) in women with female sexual dysfunction (FSD) and multiple sclerosis (MS). Clin Neurophysiol 2007. [DOI: 10.1016/j.clinph.2006.07.196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Datta S, Kavia R, Gonzales G, DasGupta R, Fowler C, Elneil S. MP-04.05. Urology 2006. [DOI: 10.1016/j.urology.2006.08.219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Brady CM, DasGupta R, Dalton C, Wiseman OJ, Berkley KJ, Fowler CJ. An open-label pilot study of cannabis-based extracts for bladder dysfunction in advanced multiple sclerosis. Mult Scler 2005; 10:425-33. [PMID: 15327041 DOI: 10.1191/1352458504ms1063oa] [Citation(s) in RCA: 185] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
The majority of patients with multiple sclerosis (MS) develop troublesome lower urinary tract symptoms (LUTS). Anecdotal reports suggest that cannabis may alleviate LUTS, and cannabinoid receptors in the bladder and nervous system are potential pharmacological targets. In an open trial we evaluated the safety, tolerability, dose range, and efficacy of two whole-plant extracts of Cannabis sativa in patients with advanced MS and refractory LUTS. Patients took extracts containing delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD; 2.5 mg of each per spray) for eight weeks followed by THC-only (2.5 mg THC per spray) for a further eight weeks, and then into a long-term extension. Assessments included urinary frequency and volume charts, incontinence pad weights, cystometry and visual analogue scales for secondary troublesome symptoms. Twenty-one patients were recruited and data from 15 were evaluated. Urinary urgency, the number and volume of incontinence episodes, frequency and nocturia all decreased significantly following treatment (P <0.05, Wilcoxon's signed rank test). However, daily total voided, catheterized and urinary incontinence pad weights also decreased significantly on both extracts. Patient self-assessment of pain, spasticity and quality of sleep improved significantly (P <0.05, Wilcoxon's signed rank test) with pain improvement continuing up to median of 35 weeks. There were few troublesome side effects, suggesting that cannabis-based medicinal extracts are a safe and effective treatment for urinary and other problems in patients with advanced MS.
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Affiliation(s)
- C M Brady
- Dept of Uro-Neurology, Institute of Neurology and National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK
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DasGupta R, Wiseman O, Fowler C. A randomised double-blind, cross-over, placebo-controlled trial of viagra in neurogenic female sexual dysfunction. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s1569-9056(03)80377-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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DasGupta R, Apostolidis A, Fowler C. Urodynamic results following successful sacral neuromodulation in women with urinary retention. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s1569-9056(03)80276-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
OBJECTIVE: Diltiazem is a calcium channel blocker that has shown potential to heal chronic anal fissures. We have prospectively evaluated the treatment of patients with anal fissure with diltiazem gel (SLA Pharma, UK). PATIENTS AND METHODS: All patients with chronic anal fissure from September 1999 to May 2000 were treated topically with 8 mg 2% diltiazem hydrochloride gel (equivalent to 2 cm of gel supplied by SLA Pharma) three times daily. The 23 patients (12 female), median age 45 (range 22-80) years had a 2-36 month (median 6 months) history of fissure. These were associated with a sentinel tag in 9 (39%) patients. RESULTS: The fissure healed in 11 (48%) of 23 patients, including 6 (75%) of 8 patients who previously failed to heal with GTN ointment. There were no recurrences at 3 months and no adverse effects. Of the 12 patients who did not respond to diltiazem, 4 have undergone sphincterotomy. CONCLUSION: Diltiazem gel has a healing rate similar to that observed with GTN ointment but there were no adverse effects, the recurrence rate was lower, and diltiazem was effective in 75% of patients previously treated unsuccessfully with GTN ointment.
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Affiliation(s)
- R. DasGupta
- Department of Colorectal Surgery, West Middlesex University Hospital, Isleworth, UK, Chelsea and Westminster Hospital NHS Trust, Suffolk, UK, The Ipswich Hospital NHS Trust, Ipswich, Suffolk, UK
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Abstract
Recent studies have yielded a number of important insights into the mechanisms of hair follicle development and cycling and have highlighted the particularly important roles played by stem cells and Wnt signaling pathways.
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Affiliation(s)
- E Fuchs
- Howard Hughes Medical Institute The University of Chicago, Illinois 60637, USA.
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Abstract
In skin, multipotent stem cells generate the keratinocytes of the epidermis, sebaceous gland, and hair follicles. In this paper, we show that Tcf3 and Lef1 control these differentiation lineages. In contrast to Lef1, which requires Wnt signaling and stabilized beta-catenin to express the hair-specific keratin genes and control hair differentiation, Tcf3 can act independently of its beta-catenin interacting domain to suppress features of epidermal terminal differentiation, in which Tcf3 is normally shut off, and promote features of the follicle outer root sheath (ORS) and multipotent stem cells (bulge), the compartments which naturally express Tcf3. These aspects of Tcf3's action are dependent on its DNA binding and Groucho repressor-binding domains. In the absence of its beta-catenin interacting domain, Lef1's behavior (Delta NLef1) seems to be markedly distinct from that of Delta NTcf3. Delta NLef1 does not suppress epidermal differentiation and promote ORS/bulge differentiation, but rather suppresses hair differentiation and gives rise to sebocyte differentiation. Taken together, these findings provide powerful evidence that the status of Tcf3/Lef complexes has a key role in controlling cell fate lineages in multipotent skin stem cells.
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Affiliation(s)
- B J Merrill
- Howard Hughes Medical Institute, Department of Molecular Genetics and Cell Biology, The University of Chicago, Chicago, Illinois 60637, USA
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Affiliation(s)
- R DasGupta
- Department of Surgery, Addenbrookes' Hospital, Cambridge, England
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Abstract
LEF/TCF DNA-binding proteins act in concert with activated beta -catenin, the product of Wnt signaling, to transactivate downstream target genes. To probe the role of activated LEF/TCF transcription factor complexes in hair follicle morphogenesis and differentiation, we engineered mice harboring TOPGAL, a beta -galactosidase gene under the control of a LEF/TCF and beta -catenin inducible promoter. In mice, TOPGAL expression was directly stimulated by a stabilized form of beta -catenin, but was also dependent upon LEF1/TCF3 in skin. During embryogenesis, TOPGAL activation occurred transiently in a subset of LEF1-positive cells of pluripotent ectoderm and underlying mesenchyme. Downgrowth of initiated follicles proceeded in the absence of detectable TOPGAL expression, even though LEF1 was still expressed. While proliferative matrix cells expressed the highest levels of Lef1 mRNAs, LEF1 concentrated in the precursor cells to the hair shaft, where TOPGAL expression was co-induced with hair-specific keratin genes containing LEF/TCF-binding motifs. LEF1 and TOPGAL expression ceased during catagen and telogen, but reappeared at the start of the postnatal hair cycle, concomitant with precortex formation. In contrast to hair shaft precursor cells, postnatal outer root sheath expressed TCF3, but not TOPGAL. TCF3 was also expressed in the putative follicle stem cells, and while TOPGAL was generally silent in this compartment, it was stimulated at the start of the hair cycle in a fashion that appeared to be dependent upon stabilization of beta -catenin. Taken together, our findings demonstrate that LEF1/TCF3 is necessary but not sufficient for TOPGAL activation, revealing the existence of positive and negative regulators of these factors in the skin. Furthermore, our findings unveil the importance of activated LEF/TCF complexes at distinct times in hair development and cycling when changes in cell fate and differentiation commitments take place.
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Affiliation(s)
- R DasGupta
- Howard Hughes Medical Institute, Department of Molecular Genetics and Cell Biology and Committee on Developmental Biology, The University of Chicago, Chicago, IL 60637, USA
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Abstract
An effector of intercellular adhesion, beta-catenin also functions in Wnt signaling, associating with Lef-1/Tcf DNA-binding proteins to form a transcription factor. We report that this pathway operates in keratinocytes and that mice expressing a stabilized beta-catenin controlled by an epidermal promoter undergo a process resembling de novo hair morphogenesis. The new follicles formed sebaceous glands and dermal papilla, normally established only in embryogenesis. As in embryologically initiated hair germs, transgenic follicles induce Lef-1, but follicles are disoriented and defective in sonic hedgehog polarization. Additionally, proliferation continues unchecked, resulting in two types of tumors also found in humans. Our findings suggest that transient beta-catenin stabilization may be a key player in the long-sought epidermal signal leading to hair development and implicate aberrant beta-catenin activation in hair tumors.
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Affiliation(s)
- U Gat
- Howard Hughes Medical Institute, The University of Chicago, Illinois 60637, USA
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DasGupta R, Fairham SA, Womack C, Burton C, Sivakumaran M. An unusual cutaneous manifestation of myelodysplastic syndrome: "pseudo-Koebner phenomenon". J Clin Pathol 1998; 51:860-1. [PMID: 10193331 PMCID: PMC500984 DOI: 10.1136/jcp.51.11.860] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
An unusual and hitherto unreported complication of myelodysplastic syndrome is reported: the "pseudo-Koebner phenomenon." The skin lesions were characterised by exuberant "fleshy" masses at the sites of intravenous cannulation and skin trauma, and by histological evidence of chronic inflammation with focal necrosis and abscess formation. No evidence of dermal infiltration by malignant haemopoietic cells was seen. The exact aetiopathology of the phenomenon is unclear but an inappropriate and exaggerated inflammatory response owing to aberrant mediator mechanisms that are known to occur in some cases of myelodysplastic syndrome may be implicated.
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Affiliation(s)
- R DasGupta
- Department of Haematology, District Hospital, Peterborough, UK
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Burton CH, Fairham SA, Millet B, DasGupta R, Sivakumaran M. Unusual aetiology of persistent back pain in a patient with multiple myeloma: infectious discitis. J Clin Pathol 1998; 51:633-4. [PMID: 9828827 PMCID: PMC500861 DOI: 10.1136/jcp.51.8.633] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A 47 year old man with multiple myeloma presented with persistent back pain caused by infectious discitis. Aspiration of the affected vertebral disc space was carried out, guided by computed tomography, and microbiological examination of the aspirate revealed Staphylococcus aureus and Mycobacterium tuberculosis. Antituberculous and antistaphylococcal antibiotic treatment resulted in a dramatic clinical response with complete resolution of the vertebral abscess. Detailed radiological and microbiological investigations are necessary to diagnose unusual causes of chronic bone pain such as discitis or infectious bone disease in patients with multiple myeloma.
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Affiliation(s)
- C H Burton
- Department of Haematology, District Hospital, Peterborough, UK
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Abstract
BACKGROUND This study was designed to test the hypothesis that the hospital resources utilized in treating pedestrian trauma would be significantly greater than that for automobile occupants. This was based on previous studies that showed that the demographic features and patterns of injury sustained by the pedestrian population were significantly different from that of automobile occupants. METHODS A hospital-based study was designed utilizing retrospective analysis of a prospective trauma database. All primary retrievals of pedestrians (n=547) and automobile occupants (n=597) involved in accidents in Central Sydney from mid-1990 to mid-1995 were included. The length of hospital stay, use of the intensive care unit (ICU) and visits to the operating theatre (Standard Resource Cost) were compared. RESULTS The age and injury severity scores were significantly higher for the pedestrian group. The length of stay (days) for the pedestrians (mean, 12 SD 14; median, 7 interquartile range (IQR) 13), was significantly higher (P < 0.0001 ) than that for the automobile occupants (mean, 7 SD 11; median, 2 IQR 6). The ICU utilization (days) for the pedestrians (mean, 1.3 SD 4.0; median, 0) was significantly higher (P < 0.0001) than that of the automobile occupants (mean, 0.6 SD 2.9; median, 0). The average operating theatre utilization per pedestrian (0.65 visits) exceeded that of automobile occupants (0.43) by 50% (P < 0.0001). CONCLUSIONS The study confirms that the acute care of pedestrian injury utilizes more hospital resources than that of automobile occupants. Resources should be allocated to meet this need both in terms of hospital reimbursement and overall directives in public health policy.
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Affiliation(s)
- R DasGupta
- Royal Prince Alfred Hospital, Camperdown, New South Wales, Austraila
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Sirotkin H, O'Donnell H, DasGupta R, Halford S, St Jore B, Puech A, Parimoo S, Morrow B, Skoultchi A, Weissman SM, Scambler P, Kucherlapati R. Identification of a new human catenin gene family member (ARVCF) from the region deleted in velo-cardio-facial syndrome. Genomics 1997; 41:75-83. [PMID: 9126485 DOI: 10.1006/geno.1997.4627] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Velo-cardio-facial syndrome (VCFS) and DiGeorge syndrome (DGS) are characterized by a wide spectrum of phenotypes, including conotruncal heart defects, cleft palate, and facial dysmorphology. Hemizygosity for a portion of chromosome 22q11 has been detected in 80-85% of VCFS/DGS patients. Both syndromes are thought to be the result of a developmental field defect. Using two independent gene-isolation procedures, we isolated a new catenin family member termed ARVCF (armadillo repeat gene deleted in VCFS) from the interval deleted in VCFS. ARVCF encodes a protein of 962 amino acids that contains a coiled coil domain and 10 tandem armadillo repeats. The primary structure of the protein is most closely related to the murine catenin p120CAS, which suggests a role for ARVCF in protein-protein interactions at adherens junctions. ARVCF is expressed ubiquitously in all fetal and adult tissues examined. This gene is hemizygous in all VCFS patients with interstitial deletions. Based on the physical location and potential functions of ARVCF, we suggest that hemizygosity at this locus may play a role in the etiology of some of the phenotypes associated with VCFS.
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Affiliation(s)
- H Sirotkin
- Department of Molecular Genetics, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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Lukinuk C, DasGupta R. Hydrofluoric acid burns: A case report. Plast Surg (Oakv) 1997. [DOI: 10.4172/plastic-surgery.1000172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Sirotkin H, Morrow B, DasGupta R, Goldberg R, Patanjali SR, Shi G, Cannizzaro L, Shprintzen R, Weissman SM, Kucherlapati R. Isolation of a new clathrin heavy chain gene with muscle-specific expression from the region commonly deleted in velo-cardio-facial syndrome. Hum Mol Genet 1996; 5:617-24. [PMID: 8733128 DOI: 10.1093/hmg/5.5.617] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Velo-cardio-facial syndrome (VCFS) and DiGeorge syndrome (DGS) are developmental disorders characterized by a spectrum of phenotypes including velopharyngeal insufficiency, conotruncal heart defects and facial dysmorphology among others. Eighty to eighty-five percent of VCFS/DGS patients are hemizygous for a portion of chromosome 22. It is likely that the genes encoded by this region play a role in the etiology of the phenotypes associated with the disorders. Using a cDNA selection protocol, we isolated a novel clathrin heavy chain cDNA (CLTD) from the VCFS/DGS minimally deleted interval. The cDNA encodes a protein of 1638 amino acids. CLTD shares significant homology, but is not identical to the ubiquitously expressed clathrin heavy chain gene. The CLTD gene also shows a unique pattern of expression, having its maximal level of expression in skeletal muscle. Velopharyngeal insufficiency and muscle weakness are common features of VCFS patients. Based on the location and expression pattern of CLTD, we suggest hemizygosity at this locus may play a role in the etiology of one of the VCFS-associated phenotypes.
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MESH Headings
- Abnormalities, Multiple/genetics
- Abnormalities, Multiple/metabolism
- Amino Acid Sequence
- Autoradiography
- Base Sequence
- Blotting, Northern
- Blotting, Southern
- Chromosome Mapping
- Chromosomes, Human, Pair 22
- Clathrin/genetics
- Clathrin Heavy Chains
- DNA, Complementary/analysis
- Face/abnormalities
- Gene Expression Regulation, Developmental
- Heart Defects, Congenital/genetics
- Humans
- In Situ Hybridization, Fluorescence
- Molecular Sequence Data
- Muscles/metabolism
- Pharynx/abnormalities
- Polymerase Chain Reaction
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Affiliation(s)
- H Sirotkin
- Department of Molecular Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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Irving C, Nieto MA, DasGupta R, Charnay P, Wilkinson DG. Progressive spatial restriction of Sek-1 and Krox-20 gene expression during hindbrain segmentation. Dev Biol 1996; 173:26-38. [PMID: 8575627 DOI: 10.1006/dbio.1996.0004] [Citation(s) in RCA: 109] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
After segmentation of the vertebrate hindbrain, expression of the zinc-finger gene Krox-20 and the receptor tyrosine kinase gene Sek-1 is precisely restricted to rhombomeres (r) 3 and 5. This precise segmental expression is likely to reflect a critical requirement for these rhombomeres to acquire a distinct and homogeneous identity and raises the question as to how this relates to the intermingling and restriction of cell movement during segmentation. We have analysed Krox-20 and Sek-1 expression in the mouse and chick hindbrain at single-cell resolution using whole-mount in situ hybridisation and immunocytochemistry. We find that, in the mouse, the presumptive r3 and r5 expression domains each arise as narrow stripes that then broaden, suggestive of a recruitment of cells to an r3/r5 identity and/or a segmental regulation of cell proliferation. In addition, we find that expression of these genes initially occurs in fuzzy domains, and that these are progressively restricted to segmental domains, although occasional "violating" cells are observed even after segmentation. We propose that the establishment and maintenance of these segmental domains may involve both a dynamic regulation of r3/r5 identity and the restriction of cell movement across rhombomere boundaries.
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Affiliation(s)
- C Irving
- Division of Developmental Neurobiology, National Institute for Medical Research, Mill Hill, London, United Kingdom
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Binnion PF, DasGupta R. Tritiated digoxin metabolism after prior treatment with propranolol or diphenylhydantoin sodium. Int J Clin Pharmacol Biopharm 1975; 12:96-101. [PMID: 1165146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Digitalis-induced arrhythmias can be suppressed by intravenous potassium, diphenylhydantoin sodium and propranolol. As it is known that hyperkalemia can interfere with the myocardial uptake of digoxin, this study was performed to determine whether diphenylhydantoin sodium or propranolol could exert any antiarrhythmic effect by altering the metabolism of 3H-digoxin and, in particular, the accumulation of the glycoside by cardiac muscle. Three groups of anesthetized dogs were given 6 muCi 3H-digoxin per kilogram intravenously, and in two groups 15 mg/kg diphenylhydantoin sodium or 3 mg/kg propranolol were injected intravenously 15 minutes prior to the glycoside. The concentration of labelled digoxin was measured in plasma up to one hour, and then tissues were removed and analyzed for digoxin content. Diphenylhydantoin sodium did not influence myocardial uptake of digoxin. It is considered its suppressant action on digitalis-induced arrhythmias is not due to any effect on the cardiac accumulation of digoxin. Propranolol did reduce the myocardial uptake of digoxin, but this was not considered of sufficient magnitude to be the main factor in suppressing arrhythmias induced by digitalis. These studies provide evidence that both diphenylhydantoin sodium and propranolol do not have a suppressant effect on digitalis-induced arrhythmias by virtue of any significant interference with the uptake of digoxin by myocardial tissue.
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