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1.
Epilepsy Behav Rep ; 22: 100595, 2023.
Article in English | MEDLINE | ID: mdl-37025370

ABSTRACT

We present a case of a young man with frightening ictal disturbance of face perception, or prosopometamorphopsia, arising from the left temporo-occipital region, leading to significant psychosocial impairment. A vivid forearm tattoo of the ictal experience conveyed its nature to the treating team and facilitated a psychotherapeutic process leading to significant psychosocial recovery. This case highlights the marked psychosocial and developmental impacts of epilepsy and the benefit of incorporating these into assessment and treatment.

2.
Preprint in English | medRxiv | ID: ppmedrxiv-22269497

ABSTRACT

SARS-CoV-2 provokes a brisk T cell response. Peptide-based studies exclude antigen processing and presentation biology and may influence T cell detection studies. To focus on responses to whole virus and complex antigens, we used intact SARS-CoV-2 and full-length proteins with DC to activate CD8 and CD4 T cells from convalescent persons. T cell receptor (TCR) sequencing showed partial repertoire preservation after expansion. Resultant CD8 T cells recognize SARS-CoV-2-infected respiratory cells, and CD4 T cells detect inactivated whole viral antigen. Specificity scans with proteome-covering protein/peptide arrays show that CD8 T cells are oligospecific per subject and that CD4 T cell breadth is higher. Some CD4 T cell lines enriched using SARS-CoV-2 cross-recognize whole seasonal coronavirus (sCoV) antigens, with protein, peptide, and HLA restriction validation. Conversely, recognition of some epitopes is eliminated for SARS-CoV-2 variants, including spike (S) epitopes in the alpha, beta, gamma, and delta variant lineages.

3.
S Afr Med J ; 110(1): 44-48, 2019 Dec 12.
Article in English | MEDLINE | ID: mdl-31865942

ABSTRACT

BACKGROUND: Trauma in South Africa (SA) has been referred to as a malignant epidemic, but the impact of trauma on the elderly has tended to be overlooked. OBJECTIVES: To address this deficit by focusing on trauma victims aged ≥65 years. METHODS: All patients aged ≥65 years who were admitted to Grey's Hospital, Pietermaritzburg, SA, following trauma between December 2012 and January 2019 were reviewed. RESULTS: Over the 6-year study period, a total of 281 patients aged ≥65 years were admitted to Grey's Hospital following trauma. There were 150 males (53.4%) and 97 females (34.5%). The sex of 34 patients was unknown. The average age was 72 years (range 65 - 97). There were 226 cases of blunt trauma, 42 cases of penetrating trauma (including two incidents of impalement following blunt trauma) and 15 cases of other types of trauma. The most common causes of blunt trauma were accidental falls (n=76), motor vehicle accidents (n=46), pedestrian vehicle accidents (n=32) and falls from a height (n=23). Gunshot wounds (n=22) and knife wounds (n=14) were the most common forms of penetrating trauma. Other trauma mainly comprised dog bites (n=6) and snakebites (n=6). There were 72 incidents of assault (25.6% of total cases). The majority of assaults were committed by a single perpetrator, and the perpetrator was frequently known to the victim. There were no significant differences in the proportions of penetrating, blunt and other trauma injuries between males and females. A total of 44 patients (15.7%) required surgical intervention, and 41 patients (14.6%) experienced complications during their hospitalisation. Respiratory, renal and cardiac complications were most frequent, and 5 patients had a cardiac arrest. Seven experienced acute kidney injury. Seventeen patients (6.0%) required intensive care unit admission and 5 (1.8%) required ventilation. Patients stayed in hospital for an average of 2.96 days (range 0 - 39). Of the patients, 241 (85.8%) survived, 32 (11.4%) died and 8 (2.9%) had an unknown outcome. CONCLUSIONS: Geriatric trauma in SA is relatively rare, but will increase as the population ages. There is a high incidence of assault as a mechanism, highlighting the fact that elderly people are a vulnerable group. Managing these patients is challenging and is associated with significant morbidity and mortality.


Subject(s)
Wounds and Injuries/epidemiology , Accidents/statistics & numerical data , Age Factors , Aged , Aged, 80 and over , Female , Humans , Incidence , Male , South Africa/epidemiology , Violence/statistics & numerical data , Wounds and Injuries/diagnosis , Wounds and Injuries/etiology
4.
Schizophr Res ; 168(1-2): 68-73, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26351160

ABSTRACT

BACKGROUND: Bullying victimisation has been suggested to contribute to paranoid ideation in general population samples and recent evidence found that individuals with an ultra high risk (UHR) for psychosis are twice as likely to have been bullied than controls. AIMS: This study sought to examine whether a history of bullying would be associated with higher levels of paranoid ideation in individuals with an UHR and in healthy controls (HCs). METHOD: The study included 64 UHR and 43 HC participants. Following the baseline assessment, participants entered a Virtual Reality (VR) London Underground train. Paranoid ideation was measured immediately after the end of the VR experience. RESULTS: Compared to HCs, UHR participants described higher levels of childhood bullying (OR 5.19, 95% CI=2.21-12.19, p<.001) and experienced more paranoid ideation during VR (χ(2)(1)=21.06, p<.001). Childhood bullying was associated with paranoid ideation during VR in both groups (χ(2)(1)=5.931, p=,021) but prolonged exposure to bullying was not associated with increased paranoid ideation. CONCLUSION: A history of bullying in childhood is particularly common in young adults at high risk for psychosis. However bullying is associated with paranoid ideation in later life, independent of clinical status, consistent with dimensional models of psychotic phenomena.


Subject(s)
Bullying , Crime Victims/psychology , Paranoid Personality Disorder/psychology , Psychotic Disorders/psychology , Adult , Female , Humans , London , Male , Paranoid Personality Disorder/epidemiology , Psychiatric Status Rating Scales , Psychotic Disorders/epidemiology , Retrospective Studies , Risk Factors , Surveys and Questionnaires , User-Computer Interface , Young Adult
5.
Cell Death Dis ; 3: e371, 2012 Aug 16.
Article in English | MEDLINE | ID: mdl-22898869

ABSTRACT

Melanoma is an aggressive and drug-resistant cancer in need of improved therapeutic strategies. Restored expression of transcriptionally silenced genes is a potential approach, but it is limited by the genetic diversity of the melanoma tumors. The atypical heat shock protein H11/HspB8 has kinase activity and is silenced in melanoma through aberrant DNA methylation. We report that its restored expression induces the death of genetically diverse melanoma lines and inhibits tumor growth through the activation of novel TAK1-dependent death pathways. These include (i) caspase-1 activation independent of the inflammasome through upregulation of apoptosis-associated speck-like protein containing a CARD (ASC), (ii) Beclin-1 upregulation through phosphorylation of mammalian target of rapamycin (mTOR) at S2481 and (iii) apoptosis caused by caspase-1-mediated Beclin-1 cleavage. These data extend current understanding of cell death-associated functions, underscore the strong therapeutic promise of H11/HspB8 and identify TAK1 as a potential intervention target in melanoma.


Subject(s)
Heat-Shock Proteins/metabolism , MAP Kinase Kinase Kinases/metabolism , Protein Serine-Threonine Kinases/metabolism , Animals , Antibiotics, Antineoplastic/toxicity , Apoptosis/drug effects , Apoptosis Regulatory Proteins/metabolism , Beclin-1 , CARD Signaling Adaptor Proteins , Caspase 1/metabolism , Cell Line, Tumor , Cytoskeletal Proteins/metabolism , DNA Methylation , Doxorubicin/toxicity , Humans , Inflammasomes/metabolism , Melanoma/genetics , Melanoma/metabolism , Melanoma/pathology , Membrane Proteins/metabolism , Mice , Mice, Nude , Molecular Chaperones , Phosphorylation , TOR Serine-Threonine Kinases/metabolism , Transplantation, Heterologous , Up-Regulation
6.
Psychol Med ; 42(9): 1835-45, 2012 Sep.
Article in English | MEDLINE | ID: mdl-22225783

ABSTRACT

BACKGROUND: Interpersonal sensitivity is a personality trait described as excessive awareness of both the behaviour and feelings of others. Although interpersonal sensitivity has been found to be one of the vulnerability factors to depression, there has been little interest in its relationship with the prodromal phase of psychosis. The aims of this study were to examine the level of interpersonal sensitivity in a sample of individuals with an at-risk mental state (ARMS) for psychosis and its relationship with other psychopathological features. METHOD: Sixty-two individuals with an ARMS for psychosis and 39 control participants completed a series of self-report questionnaires, including the Interpersonal Sensitivity Measure (IPSM), the Prodromal Questionnaire (PQ), the Ways of Coping Questionnaire (WCQ) and the Depression and Anxiety Stress Scale (DASS). RESULTS: Individuals with an ARMS reported higher interpersonal sensitivity compared to controls. Associations between interpersonal sensitivity, positive psychotic symptoms (i.e. paranoid ideation), avoidant coping and symptoms of depression, anxiety and stress were also found. CONCLUSIONS: This study suggests that being 'hypersensitive' to interpersonal interactions is a psychological feature of the putatively prodromal phase of psychosis. The relationship between interpersonal sensitivity, attenuated positive psychotic symptoms, avoidant coping and negative emotional states may contribute to long-term deficits in social functioning. We illustrate the importance, when assessing a young client with a possible ARMS, of examining more subtle and subjective symptoms in addition to attenuated positive symptoms.


Subject(s)
Anxiety, Separation , Interpersonal Relations , Prodromal Symptoms , Psychotic Disorders/physiopathology , Self Concept , Adaptation, Psychological , Adolescent , Adult , Anxiety , Case-Control Studies , Depression , Female , Humans , Male , Personality
7.
Gene Ther ; 17(3): 315-27, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19798049

ABSTRACT

Malignant melanoma is a highly aggressive and drug-resistant cancer. Virotherapy is a novel therapeutic strategy based on cancer cell lysis through selective virus replication. However, its clinical efficacy is modest, apparently related to poor virus replication within the tumors. We report that the growth compromised herpes simplex virus type 2 (HSV-2) mutant, DeltaPK, has strong oncolytic activity for melanoma largely caused by a mechanism other than replication-induced cell lysis. The ratio of dead cells (determined by trypan blue or ethidium homodimer staining) to cells that stain with antibody to the major capsid protein VP5 (indicative of productive infection) was 1.8-4.1 for different melanoma cultures at 24-72 h post-infection. Cell death was due to activation of calpain as well as caspases-7 and -3 and it was abolished by the combination of calpain (PD150606) and pancaspase (benzyloxycarbonyl-Val-Ala-Asp-fluormethyl ketone, z-VAD-fmk) inhibitors. Upregulation of the autopahgy protein Beclin-1 and the pro-apoptotic protein H11/HspB8 accompanied DeltaPK-induced melanoma oncolysis. Intratumoral DeltaPK injection (10(6)-10(7) plaque-forming unit (pfu)) significantly reduced melanoma tumor burden associated with calpain and caspases-7 and -3 activation, Beclin-1 and H11/HspB8 upregulation and activation of caspase-1-related inflammation. Complete remission was seen for 87.5% of the LM melanoma xenografts at 5 months after treatment termination. The data indicate that DeltaPK is a promising virotherapy for melanoma that functions through virus-induced programmed cell death pathways.


Subject(s)
Herpesvirus 2, Human/genetics , Melanoma/therapy , Oncolytic Virotherapy/methods , Oncolytic Viruses/genetics , Protein Serine-Threonine Kinases/genetics , Ribonucleotide Reductases/genetics , Skin Neoplasms/therapy , Animals , Apoptosis , Autophagy , Calpain/antagonists & inhibitors , Calpain/metabolism , Capsid Proteins/metabolism , Caspase 3/metabolism , Caspase 7/metabolism , Caspase Inhibitors , Cell Line, Tumor , Gene Deletion , Humans , Mice , Mice, Nude , Virus Replication , Xenograft Model Antitumor Assays
8.
J Plast Reconstr Aesthet Surg ; 63(11): 1778-86, 2010 Nov.
Article in English | MEDLINE | ID: mdl-19969515

ABSTRACT

INTRODUCTION: Health Commission Wales (Specialist Services) [HCW] are responsible for resource allocation and demand management in plastic surgery for the population of Wales (2.9 M). Since 2004, all low priority plastic surgery referrals have been screened by a single HCW Case Officer against clinical inclusion criteria before the referral is passed to the provider. Only patients fulfilling these criteria proceed to an outpatient appointment, although there is an appeals procedure. Revised guidelines were introduced in 2006. Our aim was to investigate the effectiveness of the process and the impact of the revised criteria. METHODS: The Case Officer's database was used to determine numbers of index procedures referred and those disallowed before and after the policy change. RESULTS: Since 2004 9,654 referrals have been screened. In 2005-6, 32.5% failed to meet the inclusion criteria and were disallowed. In the year after the policy revision fewer low priority patients were referred (1720 vs. 2013) and more (46.6%) were declined. Body contouring / abdominoplasty were particularly affected with 73.2% not compliant with funding criteria. CONCLUSION: The Welsh model is an efficient, effective and equitable system for demand management, which amounts to thousands of requests per year. After 2006, tighter guidelines have resulted in a higher proportion of patients not meeting the criteria for funding, particularly for body contouring / abdominoplasty procedures. Difficulties remain however in determining reproducible and clinically appropriate criteria for patients seeking plastic surgery following massive weight-loss. Whilst this process streamlines the provision of NHS plastic surgery for the people of Wales, there is a potential impact on specialist training.


Subject(s)
Health Services Needs and Demand/statistics & numerical data , Plastic Surgery Procedures/statistics & numerical data , Referral and Consultation/statistics & numerical data , Surgery, Plastic/statistics & numerical data , Female , Humans , Male , Wales
9.
J Plast Reconstr Aesthet Surg ; 62(5): 589-94, 2009 May.
Article in English | MEDLINE | ID: mdl-19233756

ABSTRACT

A syndrome now known as Ehlers-Danlos, comprising laxity and fragility of the skin associated with hypermobility of the large joints, was published in 1892 by Tschernogobow. Ehlers-Danlos type VIIA is an extremely rare form of the syndrome. While the UK-based Ehlers-Danlos Support Group recommends that the surgical management of patients with Ehlers-Danlos VIIA should be carried out in conjunction with a plastic surgeon, there is nothing in the plastic surgery literature regarding this syndrome. The management of patients suffering from Ehlers-Danlos VIIA is highly complex, as a result of the breadth of genetic and phenotypic presentations, and resulting complications. We present a review of the literature regarding this syndrome and, in particular, the surgical problems that may be encountered. A case report outlining our experience of successfully managing this condition is also presented.


Subject(s)
Ehlers-Danlos Syndrome/surgery , Plastic Surgery Procedures/methods , Child, Preschool , Cicatrix/pathology , Dermatologic Surgical Procedures , Ehlers-Danlos Syndrome/genetics , Ehlers-Danlos Syndrome/pathology , Humans , Male , Scoliosis/surgery , Skin/pathology , Wound Healing
10.
Gene Ther ; 15(20): 1397-409, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18496573

ABSTRACT

Apoptosis is a widely accepted component of the pathogenesis of Parkinson's disease (PD), a debilitating neurodegenerative disorder characterized by loss of dopaminergic neurons in the substantia nigra. However, additional death programs were implicated, and current understanding of the cycle of intracellular events that leads to the demise of these neuron Jis limited. Gene therapy strategies were proposed to inhibit apoptosis, but they have met with relatively limited success. Here we report that the antiapoptotic herpes simplex virus type 2 gene ICP10PK protects neuronally differentiated PC12 cells from death caused by 1-methyl-4-phenylpyridinium (in vitro PD model) through inhibition of calpain I activation and the resulting inhibition of Bax translocation to the mitochondria, apoptosis-inducing factor release and caspase-3 activation. Neuroprotection is through ICP10PK-mediated activation of the PI3-K/Akt survival pathway and upregulation/stabilization of the antiapoptotic protein Bcl-2 and the cytoprotective chaperone heat-shock protein 70.


Subject(s)
1-Methyl-4-phenylpyridinium/pharmacology , Apoptosis Inducing Factor/metabolism , Genetic Therapy/methods , Parkinson Disease/therapy , Protein Serine-Threonine Kinases/genetics , Ribonucleotide Reductases/genetics , Toxins, Biological/pharmacology , Animals , Apoptosis , Biomarkers/analysis , Calpain/antagonists & inhibitors , Caspase 3/analysis , Gene Expression , HSP70 Heat-Shock Proteins/metabolism , Immunoblotting , In Situ Nick-End Labeling , Mitochondria/metabolism , PC12 Cells , Parkinson Disease/genetics , Phosphatidylinositol 3-Kinases/metabolism , Protein Transport , Proto-Oncogene Proteins c-bcl-2/metabolism , Rats , Signal Transduction , bcl-2-Associated X Protein/metabolism
11.
Int J Surg ; 6(1): 45-50, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18029238

ABSTRACT

Hand injuries are the main cause of work-related disability in young adults. We have devised the Modified Hand Injury Scoring System to quantify hand, wrist and forearm injuries. This study aims to determine its value in predicting ability and time taken to return to work after such injury. Prospectively-assigned MHISS at presentation was compared with demographic, injury, employment and quality of life information 40-52months after acute hand or forearm injury. MHISS score was the only variable investigated found to predict ability to return to work. Factors not associated included age at injury, occupation, hand injury side or dominance, main earner status and compensation-seeking. Median time to return to work increased from 30 to 760days for Mild and Major MHISS categories respectively. Injury severity quantified using MHISS is an important determinant of return to work after hand or forearm injury. Only 60% of patients return to work following a Major injury and may take over a year to do so. Such information may allow the patient to make early informed personal financial and retraining decisions after their injury.


Subject(s)
Disability Evaluation , Hand Injuries , Severity of Illness Index , Adolescent , Adult , Female , Forearm Injuries , Hand Injuries/rehabilitation , Humans , Male , Middle Aged , Prospective Studies , Quality of Life , Wrist Injuries
12.
Oncogene ; 26(24): 3521-31, 2007 May 24.
Article in English | MEDLINE | ID: mdl-17173073

ABSTRACT

Molecular therapeutics is a recognized promising approach for melanoma, but relevant target genes remain elusive. We report that overload of the recently cloned H11/HspB8 induces apoptosis in 55% of examined melanoma cultures. Apoptosis was determined by activation of caspases-9 and -3 and terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling (TUNEL), and was not seen in normal melanocytes. It was associated with H11/HspB8 complexation with transforming growth factor-beta-activated kinase (TAK) 1 and activation of TAK1 and p38 mitogen activated protein 3 kinases. TAK1 was not bound, nor activated by the H11/HspB8 mutant W51C, which has dominant antiapoptotic activity. beta-Catenin was phosphorylated by activated TAK1, inhibiting its nuclear accumulation and mictophthalmia-associated transcription factor and cyclin dependent kinase 2 expression. The dominant-negative TAK1 mutant K63W inhibited beta-catenin phosphorylation and caspase activation. The data indicate that H11/HspB8 overload causes melanoma growth arrest and apoptosis through TAK1 activation and suggest that H11/HspB8 is a promising molecular therapy target.


Subject(s)
Apoptosis/physiology , Heat-Shock Proteins/metabolism , MAP Kinase Kinase Kinases/metabolism , Melanoma/pathology , Protein Serine-Threonine Kinases/metabolism , Apoptosis/drug effects , Caspases/drug effects , Caspases/metabolism , Cell Nucleus/metabolism , Cyclin-Dependent Kinase 2/drug effects , Cyclin-Dependent Kinase 2/metabolism , Doxorubicin/pharmacology , Enzyme Activation , Heat-Shock Proteins/genetics , Humans , Melanocytes/metabolism , Melanocytes/pathology , Melanoma/genetics , Microphthalmia-Associated Transcription Factor/drug effects , Microphthalmia-Associated Transcription Factor/metabolism , Molecular Chaperones , Phosphorylation , Protein Serine-Threonine Kinases/genetics , Tumor Cells, Cultured , beta Catenin/drug effects , beta Catenin/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism
13.
J Plast Reconstr Aesthet Surg ; 59(9): 969-74, 2006.
Article in English | MEDLINE | ID: mdl-16920590

ABSTRACT

The perceived benefits of bandaging for 10 days following pinnaplasty have been questioned by previous studies. The problems arising from these dressings are many [Powell BWEM. The value of head dressings in the postoperative management of the prominent ear. Br J Plast Surg 1989;42:692-4. Bartley J. How long should ears be bandaged after otoplasty? J Laryngol Otol 1998;112:531-2. Wong MC, Sylaidis P. Head dressings for pinnaplasty: a tradition not supported by evidence. Br J Plast Surg 2001;54:81-2], including their slippage [Powell BWEM. The value of head dressings in the postoperative management of the prominent ear. Br J Plast Surg 1989;42:692-4. Bradbury ET, Hewison J, Timmons MJ. Psychological and social outcome of prominent ear correction in children. Br J Plast Surg 1992;45:97-100. Jeffery SLA. Complications following correction of prominent ears: an audit review of 122 cases. Br J Plast Surg 1999;52:588-90]. Eighty children were recruited into a prospective randomised controlled trial comparing the use of a head bandage for only 24 h with a standard practise of a 10-day head bandage. A preoperative measurement of the lateral ear projection (LEP) was made. The outcome measures recorded during the two planned postoperative visits at 10 days (visit 1) and 2 months (visit 2) were: patient satisfaction score, LEP, complications and any unscheduled hospital visits associated with the surgery. There was no significant difference in LEP and patient satisfaction between the two groups at both the scheduled postoperative visits. Differences between the groups in the number of unscheduled visits (p=0.21) did not reach statistical significance. The findings indicate that it is safe and effective to use head bandage for only 24 h following surgical correction of prominent ears. This study shows no benefit from the application of a formal head bandage for any longer than 1 day.


Subject(s)
Bandages , Ear Cartilage/abnormalities , Ear Cartilage/surgery , Plastic Surgery Procedures , Postoperative Care/methods , Adolescent , Bandages/adverse effects , Child , Female , Humans , Male , Patient Satisfaction , Postoperative Complications , Postoperative Period , Prospective Studies , Treatment Outcome
14.
J Hand Surg Br ; 31(4): 439-40, 2006 Aug.
Article in English | MEDLINE | ID: mdl-16766098

ABSTRACT

There is little information in the literature regarding the clinical features, investigation, diagnosis and treatment of closed rupture of the deep transverse metacarpal ligament. We demonstrate a case with previously undescribed features and describe the surgical management.


Subject(s)
Bone Cysts/diagnostic imaging , Bone Cysts/surgery , Finger Injuries/surgery , Hand/growth & development , Ligaments/injuries , Ligaments/surgery , Metacarpal Bones/surgery , Plastic Surgery Procedures , Adolescent , Child , Child, Preschool , Female , Humans , Male , Radiography
15.
Eur J Surg Oncol ; 32(1): 80-4, 2006 Feb.
Article in English | MEDLINE | ID: mdl-16256294

ABSTRACT

AIMS: We report a prospective study examining the prognostic significance of the c-myc oncoprotein, p53 tumour suppressor gene and proliferation rate measurements in malignant melanoma. METHODS: Flow cytometry (FCM) was used to measure the expression of c-myc, p53 and proliferation parameters in patients who had received an injection of the thymidine analogue bromodeoxyuridine prior to surgery. RESULTS: Sixty-seven patients had successful FCM measurements of the three parameters. c-myc was detected in 97% of patients with a median cell positivity of 62%. The median p53 positivity was 13%. The median potential doubling time (T(pot)) of the tumours wasf 9.4 days. In univariate analysis, each of the parameters showed an association with survival in metatstatic disease with rapid proliferation (p=0.006) or overexpression of c-myc (p=0.038) related to poor survival whereas increased positivity for p53 predicted better survival (p=0.013). CONCLUSIONS: These data indicate that laser cytometric technology can be used to obtain quantitative data on oncoproteins expression and cell proliferation rates in clinical samples of malignant melanoma.


Subject(s)
Cell Proliferation , DNA, Neoplasm/genetics , Gene Expression Regulation, Neoplastic , Melanoma/genetics , Proto-Oncogene Proteins c-myc/genetics , Tumor Suppressor Protein p53/genetics , Female , Flow Cytometry , Follow-Up Studies , Humans , Male , Melanoma/mortality , Melanoma/pathology , Middle Aged , Prospective Studies , Proto-Oncogene Proteins c-myc/metabolism , Survival Rate , Time Factors , Tumor Suppressor Protein p53/metabolism
16.
J Membr Biol ; 207(1): 45-53, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16463142

ABSTRACT

Zonula occludens-1 (ZO-1), the most abundant known connexin-interacting protein in osteoblastic cells, associates with the carboxyl termini of both Cx43 and Cx45. To learn more about the role of the cormexin-ZO-1 interaction, we analyzed connexin trafficking and function in ROS 17/2.8 cells that were stably transfected either with full length Cx45 or with Cx45 lacking 34 or 37 amino acids on the carboxyl terminus (Cx45t34 or Cx45t37). All three proteins were transported to appositional membranes in the transfected cells: Cx45 and Cx45t34 displayed a punctate appositional membrane-staining pattern, while Cx45t37 staining at appositional membranes was more linear. Expression of Cx45 decreased gap junction communication as assayed by dye transfer, while expression of Cx45t34 or Cx45t37 increased the amount of dye transfer seen in these cells. We found that Cx43, Cx45 and Cx45t34 co-precipitated with ZO-1 in these cells, while Cx45t37 did not. We also found that Cx45t37 was much more soluble in 1% Triton X-100 than the other connexins examined. In addition, Cx45t37 migrated to a fraction of lighter buoyant density on sucrose flotation gradients than Cx43, Cx45, ZO-1 and Cx45t34. As ZO-1 is an actin-binding protein, this suggested that the differences in Cx45t37 solubility might be due to a difference between the interaction of gap junctions and the actin cytoskeleton in the ROS/Cx45t37 and in the other transfected ROS cells. To examine this possibility, the transfected ROS cells were stained with fluorescently labeled phalloidin and demonstrated that there was a notable loss of actin stress fibers in the ROS/Cx45t37 cells. These findings suggest that association with ZO-1 alters the plasma membrane localization of Cx45 by removing it from a lipid raft compartment and rendering it Triton-insoluble, presumably by promoting an interaction with the actin cytoskeleton; they also suggest that Cx45 has a complex binding interaction with ZO-1 that involves either an extended carboxyl terminal domain or two distinct binding sites.


Subject(s)
Cell Membrane/metabolism , Connexins/metabolism , Membrane Proteins/metabolism , Mutation , Phosphoproteins/metabolism , Animals , Binding Sites/genetics , Cell Line, Tumor , Cell Membrane/genetics , Connexins/biosynthesis , Connexins/genetics , Humans , Octoxynol , Protein Binding/genetics , Protein Structure, Tertiary/genetics , Rats , Sequence Deletion/genetics , Solubility , Stress Fibers/metabolism , Sucrose , Zonula Occludens-1 Protein
17.
Melanoma Res ; 13(3): 271-7, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12777982

ABSTRACT

This prospective study investigated the clinical significance of cell kinetics, measured using bromodeoxyuridine injection and flow cytometry, in primary and metastatic cutaneous malignant melanoma. The findings illustrate that melanoma is a relatively slowly proliferating tumour, with a median potential doubling time (T(pot)) of 8.6 days. There were no significant differences in cell kinetics between primary and secondary disease. Both the duration of the S phase (T(s)) and T(pot), but not the labelling index (LI), showed a correlation with some of the main clinicopathological features in primary disease, including Breslow thickness. On univariate analysis, a short T(pot) and a high LI were associated with shorter disease-free intervals and overall survival for metastatic but not primary lesions. On multivariate analysis, these parameters retained significance when analysed separately with the main clinicopathological variables. These findings suggest that assessment of proliferation in melanoma is able to refine the available prognostic information and identify patients with a poor clinical outcome.


Subject(s)
Melanoma/pathology , S Phase/physiology , Skin Neoplasms/pathology , Aged , Bromodeoxyuridine/metabolism , Cell Division , DNA, Neoplasm/analysis , Disease-Free Survival , Female , Humans , Male , Melanoma/metabolism , Melanoma/mortality , Middle Aged , Mitosis , Prognosis , Skin Neoplasms/metabolism , Skin Neoplasms/mortality , Survival Analysis , Treatment Outcome
18.
J Struct Biol ; 137(1-2): 15-22, 2002.
Article in English | MEDLINE | ID: mdl-12064929

ABSTRACT

The molecular packing arrangement within collagen fibrils has a significant effect on the tensile properties of tissues. To date, most studies have focused on homotypic fibrils composed of type I collagen. This study investigates the packing of type I/III collagen molecules in heterotypic fibrils of colonic submucosa using a combination of X-ray diffraction data, molecular model building, and simulated X-ray diffraction fibre diagrams. A model comprising a 70-nm-diameter D- (approximately 65 nm) axial periodic structure containing type I and type III collagen chains was constructed from amino acid scattering factors organised in a liquid-like lateral packing arrangement simulated using a classical Lennard-Jones potential. The models that gave the most accurate correspondence with diffraction data revealed that the structure of the fibril involves liquid-like lateral packing combined with a constant helical inclination angle for molecules throughout the fibril. Combinations of type I:type III scattering factors in a ratio of 4:1 gave a reasonable correspondence with the meridional diffraction series. The attenuation of the meridional intensities may be explained by a blurring of the electron density profile of the D period caused by nonspecific or random interactions between collagen types I and III in the heterotypic fibril.


Subject(s)
Collagen Type III/chemistry , Collagen Type I/chemistry , Fibrillar Collagens/chemistry , Animals , Biophysical Phenomena , Biophysics , Collagen Type I/ultrastructure , Collagen Type III/ultrastructure , Colon/metabolism , Fibrillar Collagens/ultrastructure , Intestinal Mucosa/metabolism , Models, Molecular , Rats , Scattering, Radiation , X-Ray Diffraction , X-Rays
19.
Br J Plast Surg ; 54(4): 363-5, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11355997

ABSTRACT

A case of a degloving injury to the foot is presented in a patient who also sustained severe contralateral lower-limb trauma. We report a technique for salvaging the foot by replacing the degloved skin as a full-thickness graft and securing it using the vacuum-assisted closure (VAC) device. A good outcome was achieved and technical tips are provided to facilitate reproduction of the procedure.


Subject(s)
Foot Injuries/surgery , Plastic Surgery Procedures/methods , Bone Wires , Foot Injuries/rehabilitation , Humans , Male , Middle Aged , Occlusive Dressings , Plastic Surgery Procedures/rehabilitation , Skin Transplantation/methods , Vacuum , Weight-Bearing
20.
J Biol Chem ; 276(25): 23051-5, 2001 Jun 22.
Article in English | MEDLINE | ID: mdl-11313345

ABSTRACT

The relative expression of connexin43 and connexin45 modulates gap junctional communication and production of bone matrix proteins in osteoblastic cells. It is likely that changes in gap junction permeability are determined by the interaction between these two proteins. Cx43 interacts with ZO-1, which may be involved in trafficking of Cx43 or facilitating interactions between Cx43 and other proteins. In this study we sought to identify proteins that associate with Cx45 by coprecipitation in non-denaturing conditions. Cx45 was isolated with a 220-kDa protein that we identified as ZO-1. Under the same conditions, Cx43 also was isolated with anti-Cx45 antiserum from Cx45-transfected ROS cells (ROS/Cx45 cells). Cx43 antiserum could also coprecipitate ZO-1 in the transfected and untransfected ROS cells. Double label immunofluorescence studies showed that ZO-1, Cx43, and Cx45 colocalized at appositional membranes in ROS/Cx45 cells suggesting that all three proteins are normally associated in the cells. Additionally, we found that in vitro translated ZO-1 binds to the carboxyl-terminal of Cx45 indicating that there is a direct interaction between the carboxyl-terminal of Cx45 and ZO-1. These studies demonstrate that ZO-1 interacts with Cx45 as well as with Cx43, and suggest that the interaction of connexins with ZO-1 may play a role in regulating the composition of the gap junction and may modulate connexin-connexin interactions.


Subject(s)
Connexin 43/metabolism , Connexins/metabolism , Membrane Proteins/metabolism , Osteoblasts/metabolism , Phosphoproteins/metabolism , Precipitin Tests , Protein Binding , Tumor Cells, Cultured , Zonula Occludens-1 Protein
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