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1.
Sci Rep ; 13(1): 17996, 2023 10 21.
Article in English | MEDLINE | ID: mdl-37865672

ABSTRACT

Radar-based human activity recognition (HAR) offers a non-contact technique with privacy protection and lighting robustness for many advanced applications. Complex deep neural networks demonstrate significant performance advantages when classifying the radar micro-Doppler signals that have unique correspondences with human behavior. However, in embedded applications, the demand for lightweight and low latency poses challenges to the radar-based HAR network construction. In this paper, an efficient network based on a lightweight hybrid Vision Transformer (LH-ViT) is proposed to address the HAR accuracy and network lightweight simultaneously. This network combines the efficient convolution operations with the strength of the self-attention mechanism in ViT. Feature Pyramid architecture is applied for the multi-scale feature extraction for the micro-Doppler map. Feature enhancement is executed by the stacked Radar-ViT subsequently, in which the fold and unfold operations are added to lower the computational load of the attention mechanism. The convolution operator in the LH-ViT is replaced by the RES-SE block, an efficient structure that combines the residual learning framework with the Squeeze-and-Excitation network. Experiments based on two human activity datasets indicate our method's advantages in terms of expressiveness and computing efficiency over traditional methods.


Subject(s)
Accidental Injuries , Radar , Humans , Electric Power Supplies , Human Activities , Learning
2.
Am J Transplant ; 17(4): 944-956, 2017 04.
Article in English | MEDLINE | ID: mdl-27801552

ABSTRACT

T helper 17 (Th17)-dependent autoimmune responses can develop after heart or lung transplantation and are associated with fibro-obliterative forms of chronic rejection; however, the specific self-antigens involved are typically different from those associated with autoimmune disease. To investigate the basis of these responses, we investigated whether removal of regulatory T cells or blockade of function reveals a similar autoantigen bias. We found that Th17 cells specific for collagen type V (Col V), kα1-tubulin, and vimentin were present in healthy adult peripheral blood mononuclear cells, cord blood, and fetal thymus. Using synthetic peptides and recombinant fragments of the Col V triple helical region (α1[V]), we compared Th17 cells from healthy donors with Th17 cells from Col V-reactive heart and lung patients. Although the latter responded well to α1(V) fragments and peptides in an HLA-DR-restricted fashion, Th17 cells from healthy persons responded in an HLA-DR-restricted fashion to fragments but not to peptides. Col V, kα1-tubulin, and vimentin are preferred targets of a highly conserved, hitherto unknown, preexisting Th17 response that is MHC class II restricted. These data suggest that autoimmunity after heart and lung transplantation may result from dysregulation of an intrinsic mechanism controlling airway and vascular homeostasis.


Subject(s)
Autoantigens/immunology , Collagen Type V/immunology , Immunity, Cellular/immunology , T-Lymphocytes, Regulatory/immunology , Th17 Cells/immunology , Tubulin/immunology , Vimentin/immunology , Adolescent , Adult , Child , Female , Humans , Leukocytes, Mononuclear , Male , Middle Aged , Young Adult
4.
Br J Dermatol ; 175(3): 555-60, 2016 Sep.
Article in English | MEDLINE | ID: mdl-27037527

ABSTRACT

BACKGROUND: Repigmentation is an essential outcome measure in vitiligo. However, clinical studies describing vitiligo repigmentation patterns are lacking. OBJECTIVES: To assess and clearly define the repigmentation patterns in a series of patients with vitiligo, correlating these with clinicoepidemiological characteristics. METHODS: Patients with vitiligo seen at least at twice (initial consultation and follow-up visit) in the Department of Paediatric Dermatology, Hôpital Pellegrin des Enfants, Bordeaux University Hospital from 2006 to 2014 were included. Clinical photographs and case records were reviewed. RESULTS: There were 109 patients (64 female, 45 male) mostly with Fitzpatrick skin type III (n = 67, 61%). The majority had nonsegmental (n = 71, 65%) or segmental vitiligo (n = 29, 27%). In total 172 representative vitiligo lesions were analysed. Overall, a combined pattern of repigmentation was most commonly seen (n = 106, 62%). The combined pattern occurred more frequently in patients with segmental vs. nonsegmental vitiligo (P = 0·009), whereas the diffuse pattern was more frequent in the latter (P = 0·007). Diffuse repigmentation was the predominant pattern on the eyelids (P < 0·001). We observed a new pattern in sites with few to absent hair follicles, which we propose to call 'medium spotted repigmentation'. This begins as circular macules of repigmentation, wider than 5 mm in diameter, which, from the outset, are larger than the initial macules of perifollicular repigmentation. This study is limited by its retrospective nature and small sample size for subgroup assessment. CONCLUSIONS: The combined pattern of repigmentation was most frequently observed. Medium spotted repigmentation is a new pattern, which will benefit from larger studies for a better understanding.


Subject(s)
Skin Pigmentation , Vitiligo/pathology , Adolescent , Child , Child, Preschool , Cross-Sectional Studies , Dermatologic Agents/therapeutic use , Eyelid Diseases/pathology , Eyelid Diseases/therapy , Female , Glucocorticoids/therapeutic use , Humans , Infant , Male , Prednisone/therapeutic use , Ultraviolet Therapy , Vitiligo/therapy
6.
Br J Dermatol ; 172(6): 1535-1540, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25641313

ABSTRACT

BACKGROUND: Objective outcome measures for melasma severity are essential for the evaluation of severity as well as results of treatment. The modified Melasma Area and Severity Index (mMASI) score is a validated tool for assessing melasma severity but is often subject to inter-observer variability. OBJECTIVES: To develop and validate a novel image analysis software designed to automatically calculate the area and degree of hyperpigmentation in melasma from computer image analysis of whole-face digital photographs, thereby deriving an automated mMASI score (aMASI). METHODS: The algorithm was developed in collaboration between dermatologists and image analysis experts. Firstly, using an adaptive threshold method, the algorithm identifies, segments and calculates the areas involved. It then calculates the darkness. Finally, the derived area and darkness are then used to calculate mMASI. The scores derived from the algorithm are validated prospectively. Twenty-nine patients with melasma using depigmenting agents were recruited for validation. Three dermatologists scored mMASI at baseline and post-treatment using standardized photographs. These scores were compared with aMASI scores derived from computer analysis. RESULTS: aMASI scores correlated well with clinical mMASI pre-treatment (r = 0·735, P < 0·001) and post-treatment (r = 0·608, P < 0·001). aMASI was reliable in detecting changes with treatment. These changes in aMASI scores correlated well with changes in clinician-assessed mMASI (r = 0·622, P < 0·001). CONCLUSIONS: This study proposes a novel approach in melasma scoring using digital image analysis. It holds promise as a tool that would enable clinicians worldwide to standardize melasma severity scoring and outcome measures in an easy and reproducible manner, enabling different treatment options to be compared accurately.


Subject(s)
Algorithms , Facial Dermatoses/pathology , Melanosis/pathology , Female , Humans , Image Processing, Computer-Assisted/methods , Male , Middle Aged , Pilot Projects , Software
7.
J Clin Endocrinol Metab ; 100(1): E187-90, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25295623

ABSTRACT

CONTEXT: Autoimmune endocrinopathies demonstrate a profound gender bias, but the reasons for this remain obscure. The 1000 genes on the X chromosome are likely to be implicated in this inherent susceptibility; various theories, including skewed X chromosome inactivation and fetal microchimerism, have been proposed. GPR174 is an Xq21 putative purinergic receptor that is widely expressed in lymphoid tissues. A single-nucleotide polymorphism, rs3827440, encoding Ser162Pro, has recently been associated with Graves' disease in Chinese and Polish populations, suggesting a role of this X chromosome gene in autoimmune disease. OBJECTIVE: We investigated the role of rs3827440 in a UK cohort of patients with autoimmune Addison's disease (AAD). Samples from 286 AAD cases and 288 healthy controls were genotyped using TaqMan single-nucleotide polymorphism genotyping assays (C_25954273_10) on the Applied Biosystems 7900HT Fast real-time PCR system. DESIGN: Using a dominant (present/absent) model, the serine-encoding T allele of rs3827440 was present in 189 of 286 AAD patients (66%) compared with 132 of 288 unaffected controls (46%) [P = .010, odds ratio 1.80 (5%-95% confidence interval 1.22-2.67)]. An allele dosage model found a significant excess of the T allele in AAD patients compared with controls [P = .03, odds ratio 1.34 (5%-95% confidence interval 1.07-1.67)]. CONCLUSION: We have demonstrated a significant association of this X chromosome-encoded immunoreceptor with AAD for the first time. This X-linked gene could have a more generalized role in autoimmunity pathogenesis: G protein-coupled receptors are promising drugable targets, and further work to elucidate the functional role of GPR174 is now warranted.


Subject(s)
Addison Disease/genetics , Genes, X-Linked , Genetic Predisposition to Disease , Polymorphism, Single Nucleotide , Receptors, G-Protein-Coupled/genetics , Addison Disease/immunology , Alleles , Female , Gene Frequency , Genetic Association Studies , Genotype , Humans , Male
8.
Am J Transplant ; 14(7): 1512-22, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24866539

ABSTRACT

IL17-dependent autoimmunity to collagen type V (Col V) has been associated with lung transplant obliterative bronchiolitis. Unlike the T helper 1 (Th1)-dependent immune responses to Tetanus Toxoid (TT), the Th17 response to Col V in lung transplant patients and its Th1/17 variant observed in coronary artery disease patients requires IL-1ß, tumor necrosis factor α and CD14(+) cells. Given the involvement of the P2X7 receptor (P2X7R) in monocyte IL-1ß responses, we investigated its role in Th17-, Th1/17- and Th1-mediated proinflammatory responses. Transfer of antigen-pulsed peripheral blood mononucleated cells (PBMCs) from Col V-reactive patients into SCID mouse footpads along with P2X7R antagonists revealed a selective inhibition of Col V-, but not TT-specific swelling responses. P2X7R inhibitors blocked IL-1ß induction from monocytes, including both Col V-α1 peptide-induced (T-dependent), as well as native Col V-induced (T-independent) responses. Significantly higher P2X7R expression was found on CXCR3(neg) CCR4(+)/6(+) CD4(+) [Th17] versus CXCR3(+)CCR4/6(neg) CD4(+) [Th1] subsets in PBMCs, suggesting that the paradigm of selective dependence on P2X7R might extend beyond Col V autoimmunity. Indeed, P2X7R inhibitors suppressed not only anti-Col V, but also Th1/17-mediated alloimmunity, in a heart transplant patient without affecting anti-viral Epstein-Barr virus responses. These results suggest that agents targeting the P2X7R might effectively treat Th17-related transplant pathologies, while maintaining Th1-immunity to infection.


Subject(s)
Heart Transplantation , Immunity, Cellular/immunology , Interleukin-17/immunology , Lung Transplantation , Monocytes/immunology , Receptors, Purinergic P2X7/metabolism , Th1 Cells/immunology , Animals , Antineoplastic Agents/pharmacology , Autoimmunity/immunology , Collagen Type V/immunology , Collagen Type V/metabolism , Flow Cytometry , Graft Rejection/immunology , Humans , Hypersensitivity, Delayed , Immunoenzyme Techniques , Interferon-gamma , Interleukin-17/metabolism , Mice , Mice, SCID , Monocytes/metabolism , Monocytes/pathology , Receptors, Purinergic P2X7/chemistry , Receptors, Purinergic P2X7/immunology , Suramin/pharmacology , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , T-Lymphocytes/pathology , Th1 Cells/metabolism , Th1 Cells/pathology
9.
J Intern Med ; 275(2): 104-15, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24330030

ABSTRACT

Primary adrenal insufficiency (PAI), or Addison's disease, is a rare, potentially deadly, but treatable disease. Most cases of PAI are caused by autoimmune destruction of the adrenal cortex. Consequently, patients with PAI are at higher risk of developing other autoimmune diseases. The diagnosis of PAI is often delayed by many months, and most patients present with symptoms of acute adrenal insufficiency. Because PAI is rare, even medical specialists in this therapeutic area rarely manage more than a few patients. Currently, the procedures for diagnosis, treatment and follow-up of this rare disease vary greatly within Europe. The common autoimmune form of PAI is characterized by the presence of 21-hydroxylase autoantibodies; other causes should be sought if no autoantibodies are detected. Acute adrenal crisis is a life-threatening condition that requires immediate treatment. Standard replacement therapy consists of multiple daily doses of hydrocortisone or cortisone acetate combined with fludrocortisone. Annual follow-up by an endocrinologist is recommended with the focus on optimization of replacement therapy and detection of new autoimmune diseases. Patient education to enable self-adjustment of dosages of replacement therapy and crisis prevention is particularly important in this disease. The authors of this document have collaborated within an EU project (Euadrenal) to study the pathogenesis, describe the natural course and improve the treatment for Addison's disease. Based on a synthesis of this research, the available literature, and the views and experiences of the consortium's investigators and key experts, we now attempt to provide a European Expert Consensus Statement for diagnosis, treatment and follow-up.


Subject(s)
Addison Disease/diagnosis , Addison Disease/drug therapy , Adrenal Cortex/immunology , Autoimmunity , Cortisone/analogs & derivatives , Hydrocortisone/administration & dosage , Prednisolone/administration & dosage , Acute Disease , Addison Disease/complications , Addison Disease/immunology , Addison Disease/prevention & control , Adrenal Insufficiency/diagnosis , Adrenal Insufficiency/drug therapy , Algorithms , Autoantibodies/blood , Chronic Disease , Consensus , Cortisone/administration & dosage , Diagnosis, Differential , Drug Administration Schedule , Drug Interactions , Emergency Treatment/methods , Europe , Female , Humans , Male , Pregnancy , Pregnancy Complications/diagnosis , Pregnancy Complications/drug therapy , Steroid 21-Hydroxylase/immunology
11.
Clin Otolaryngol ; 37(3): 188-96, 2012 Jun.
Article in English | MEDLINE | ID: mdl-22564341

ABSTRACT

OBJECTIVES: The study aims to perform static and dynamic quantitative assessment of the anatomical changes of the upper airway before and after modified uvulopalatal flap and lateral pharyngoplasty and comparison of the improvement in airway dimensions, collapsibility and extent of normalisation to that of control patients. DESIGN: Prospective case-controlled study. SETTING: Computer-assisted quantitative measurement is used to compare upper airway parameters before and after modified uvulopalatal flap and lateral pharyngoplasty in patients with obstructive sleep apnoea (OSA). PARTICIPANTS: Patients with obstructive sleep apnoea diagnosed on sleep study and failed positive airway pressure therapy. MAIN OUTCOME MEASURES: Sleep study results, upper airway parameters and symptom score following surgery and its comparison to normal patients to assess the degree and extent of normalisation. RESULTS: Thirty-five study and 32 control subjects were recruited and completed the study. All the retropalatal airway dimensions like area, transverse diameter, longitudinal diameter and collapsibility showed statistically significant improvement following surgery. The success rate of this surgery is 43% (15 of 35) overall, 58% (14 of 24) for patients with isolated palatal obstruction and only 9% (1 of 11) for patients with multi-level obstruction. Comparing obstructive sleep apnoea to the control subjects, there are obvious and logical differences in their biostatistics, sleep study parameters and airway dimensions. The postoperative obstructive sleep apnoea retropalatal longitudinal diameter has a higher tendency of normalising to be comparable to those of control patients. CONCLUSIONS: Modified uvulopalatal flap and lateral pharyngoplasty is an effective surgical technique for the treatment of obstructive sleep apnoea. The surgery increases the resting retropalatal dimensions and reduces the retropalatal collapsibility.


Subject(s)
Endoscopy/methods , Image Processing, Computer-Assisted/instrumentation , Palate, Soft/surgery , Pharynx/surgery , Sleep Apnea, Obstructive/physiopathology , Sleep Apnea, Obstructive/surgery , Surgical Flaps , Uvula/surgery , Case-Control Studies , Female , Humans , Male , Middle Aged , Polysomnography , Prospective Studies , Tonsillectomy , Treatment Outcome , Videotape Recording
12.
Br J Dermatol ; 166(1): 196-9, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21790525

ABSTRACT

BACKGROUND: Vitiligo in hair-bearing areas is often associated with leucotrichia. Repigmentation of leucotrichia has been reported mainly with tissue and follicular hair grafts. OBJECTIVES: To evaluate the repigmentation response of leucotrichia after noncultured cellular grafting. METHODS: We retrospectively reviewed patients with stable generalized and segmental vitiligo who underwent noncultured cellular grafting from March 2008 to November 2010 in areas with leucotrichia. The percentage repigmentation of white hairs was based on clinical assessment and standardized digital photography, and was graded 'poor', 'fair', 'good' or 'excellent', corresponding to a scale of 0-100% repigmentation with respective intervals of 25%. RESULTS: Eighty-four patients with vitiligo underwent cellular grafting; of these, 13 had grafting in areas with leucotrichia. Twelve patients (92%) had poor repigmentation of leucotrichia 3 months after transplant. One patient defaulted follow-up after this period. At 6months, fair repigmentation was achieved in eight out of the 12 remaining patients (67%). After 9-12months, however, 91% (10 out of 11) of the patients achieved good or excellent repigmentation. One patient did not reach the 9-month follow-up period at the time of data analysis. Leucotrichia of eyebrows yielded excellent repigmentation in eight out of nine patients, whereas hairs on the limbs and scalp showed good repigmentation in two out of two patients at 9-12 months. CONCLUSIONS: Good to excellent repigmentation of leucotrichia can be achieved with noncultured cellular grafting, obviating the need for hair transplantation.


Subject(s)
Hair Diseases/surgery , Skin Pigmentation , Skin Transplantation/methods , Vitiligo/surgery , Adolescent , Adult , Female , Hair Color , Humans , Male , Middle Aged , Retrospective Studies , Transplantation, Autologous , Treatment Outcome , Young Adult
13.
Am J Transplant ; 12(3): 640-8, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22151236

ABSTRACT

To investigate the role of donor-specific indirect pathway T cells in renal transplant tolerance, we analyzed responses in peripheral blood of 45 patients using the trans-vivo delayed-type hypersensitivity assay. Subjects were enrolled into five groups-identical twin, clinically tolerant (TOL), steroid monotherapy (MONO), standard immunosuppression (SI) and chronic rejection (CR)-based on transplant type, posttransplant immunosuppression and graft function. The indirect pathway was active in all groups except twins but distinct intergroup differences were evident, corresponding to clinical status. The antidonor indirect pathway T effector response increased across patient groups (TOL < MONO < SI < CR; p < 0.0001) whereas antidonor indirect pathway T regulatory response decreased (TOL > MONO = SI > CR; p < 0.005). This pattern differed from that seen in circulating naïve B-cell numbers and in a cross-platform biomarker analysis, where patients on monotherapy were not ranked closest to TOL patients, but rather were indistinguishable from chronically rejecting patients. Cross-sectional analysis of the indirect pathway revealed a spectrum in T-regulatory:T-effector balance, ranging from TOL patients having predominantly regulatory responses to CR patients having predominantly effector responses. Therefore, the indirect pathway measurements reflect a distinct aspect of tolerance from the recently reported elevation of circulating naïve B cells, which was apparent only in recipients off immunosuppression.


Subject(s)
B-Lymphocytes/immunology , Graft Rejection/immunology , Immune Tolerance/immunology , Kidney Transplantation/immunology , T-Lymphocytes/immunology , Tissue Donors , Humans , Immunosuppression Therapy , Prognosis , Signal Transduction
14.
Clin Exp Dermatol ; 37(2): 118-21, 2012 Mar.
Article in English | MEDLINE | ID: mdl-21790721

ABSTRACT

BACKGROUND: Lymphomatoid papulosis (LyP) is a low-grade cutaneous lymphoma, which lies within the spectrum of primary cutaneous CD30-positive lymphoproliferative disorders. Around 10-20% of LyP cases are associated with a second lymphoma. AIM: To analyse a cohort of Asian patients with LyP, diagnosed from 1987 to 2007 at the National Skin Centre (NSC), Singapore, in terms of epidemiology, treatment and association with a second lymphoma. METHODS: Patients were identified through the NSC clinical and histological databases. RESULTS: During this period, 13 patients were diagnosed with LyP based on clinicopathological criteria. The mean age at diagnosis was 41 years, the male : female ratio was 2.3 : 1, and 92% of the patients were Chinese. Recurrent papulonecrotic lesions were present for a mean of 3 years before diagnosis. Treatment of LyP comprised monotherapy (n = 4) or combination therapy (n = 9) using corticosteroids, oral antibiotics, methotrexate and/or phototherapy. Mean duration of follow-up was 6.4 years. Eight patients (61.5%) were diagnosed with a second lymphoma, either before (n = 2), concurrently with (n = 1) or after (n = 5) the diagnosis of LyP. Mycosis fungoides (MF) was the commonest lymphoma (78%, n = 7), followed by primary cutaneous anaplastic large-cell lymphoma (12%, n = 2). There was one death (mortality rate 7.7%), which occurred in a patient who had developed stage IIA MF after LyP, which subsequently progressed to systemic T-cell lymphoma. CONCLUSIONS: LyP is a chronic, relapsing disease with considerable morbidity, but an overall good prognosis. A strikingly large proportion of our Asian patients (61.5%) had a second lymphoma, compared with previous studies. This emphasizes the importance of regular lifetime surveillance for associated lymphomas in all patients with LyP.


Subject(s)
Asian People , Lymphomatoid Papulosis/epidemiology , Skin Neoplasms/epidemiology , Adolescent , Adult , Aged , Cohort Studies , Female , Humans , Lymphoma/epidemiology , Lymphoma/ethnology , Lymphomatoid Papulosis/ethnology , Lymphomatoid Papulosis/pathology , Male , Middle Aged , Singapore/epidemiology , Skin Neoplasms/ethnology , Skin Neoplasms/pathology , Young Adult
15.
Curr Pharm Biotechnol ; 12(8): 1117-27, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21470146

ABSTRACT

Drug discovery and development are intense, lengthy and interdisciplinary processes. Traditionally, drugs were discovered by synthesizing compounds in time-consuming multi-step experimental investigations followed by in vitro and in vivo biological screening. Promising candidates were then further studied for their pharmacokinetic properties, metabolism and potential toxicity. Today, the process of drug discovery has been revolutionized due to the advances in genomics, proteomics, and bioinformatics. Efficient technologies such as combinatorial chemistry, high throughput screening (HTS), virtual screening, de novo design and structure-based drug design contribute greatly to drug discovery. Peptides are emerging as a novel class of drugs for cancer therapy, and many efforts have been made to develop peptide-based pharmacologically active compounds. This paper presents a review of current advances and novel approaches in experimental and computational drug discovery and design. We also present a novel bioactive peptide analogue, designed using the Resonant Recognition Model (RRM), and discuss its potential use for cancer therapeutics.


Subject(s)
Drug Design , Drug Discovery , Peptides/therapeutic use , Amino Acid Sequence , Animals , Humans , L-Lactate Dehydrogenase/metabolism , Microscopy, Confocal , Molecular Sequence Data , Neoplasms/drug therapy
16.
Singapore Med J ; 51(9): e158-60, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20938601

ABSTRACT

We report an unusual case of a 76-year-old woman with primary cutaneous amyloidosis who initially presented with features of asteatotic eczema that was unresponsive to topical corticosteroid treatment. Histological examination revealed amyloid deposits involving the superficial and deep dermis. These lesions later gradually evolved into erythematous nodules, and a second biopsy performed 29 months after the initial presentation again revealed diffuse collections of amyloid throughout the dermis. Further investigations did not reveal evidence of systemic involvement, thus indicating a diagnosis of primary cutaneous nodular amyloidosis. The initial presentation as eczematous lesions illustrates the importance of clinicopathological correlation and subsequent follow-up.


Subject(s)
Amyloidosis/diagnosis , Eczema/diagnosis , Skin Diseases/diagnosis , Adrenal Cortex Hormones/therapeutic use , Aged , Amyloid , Amyloidosis/complications , Biopsy , Collagen/chemistry , Congo Red/pharmacology , Dermatology/methods , Eczema/complications , Female , Humans , Skin , Skin Diseases/pathology
17.
J Appl Microbiol ; 109(1): 292-303, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20070444

ABSTRACT

AIMS: In this study, we used two molecular fingerprinting methods to investigate the genetic and clonal relationship shared by Australian Salmonella Sofia isolates. METHODS AND RESULTS: A total of 84 Australian Salm. Sofia isolates from various states in Australia were typed using pulsed-field gel electrophoresis (PFGE) (XbaI and SpeI) and repetitive element PCR (REP1R-I primer). The previous problem of DNA degradation of Salm. Sofia strains was solved by modifying the lysis solution used to treat the bacterial plugs, allowing Salm. Sofia to be subtyped using PFGE. Molecular typing of isolates resulted in the generation of eight XbaI, six SpeI and five REP1 pattern profiles. Individual typing methods showed low discrimination index values (<0·5), indicating the poor discriminatory ability of the methods. However, the combination of the typing methods was able to improve the discrimination of isolates, further dividing them into 16 subtypes and raising the index value to 0·721. CONCLUSIONS: The combination of typing methods was shown to be the best approach to fingerprint Salm. Sofia. The Australian Salm. Sofia isolates only showed limited genetic diversity and probably share a clonal relationship. A majority of the Salm. Sofia isolates were not geographically restricted with the predominant pattern subtype observed amongst the isolates from various states. SIGNIFICANCE AND IMPACT OF THE STUDY: We have successfully devised a PFGE protocol that counteracts DNase activity of Salm. Sofia, enabling typing of this serovar.


Subject(s)
Electrophoresis, Gel, Pulsed-Field/methods , Molecular Typing/methods , Salmonella enterica/classification , Australia , DNA Fingerprinting/methods , DNA Primers , DNA, Bacterial/analysis , Polymerase Chain Reaction/methods , Salmonella enterica/genetics , Salmonella enterica/isolation & purification
18.
Am J Transplant ; 9(5): 1087-98, 2009 May.
Article in English | MEDLINE | ID: mdl-19344431

ABSTRACT

Alemtuzumab induction with 60 days of tacrolimus treatment and continuous sirolimus treatment prevented acute rejection in nine of 10 consecutive renal allograft recipients. All patients are alive with a functioning kidney graft at 27-39 months of follow-up. Extensive immune monitoring was performed in all patients. Alloantibody detection, cytokine kinetics assay (CKA), and trans vivo delayed-type hypersensitivity (DTH) assay were performed every 6 months showing correlation with clinical evolution. Despite alloantibody presence in five patients, eight patients remain without the need for specific treatment and only sirolimus monotherapy in decreasing dosage. Four patients take only 1 mg sirolimus daily with levels of 3-4 ng/mL. One patient showed clinical signs of rejection at month 9 post-transplant, with slow increase in serum creatinine and histological signs of mixed cellular (endarteritis) and humoral rejection (C4d positivity in peritubular capillaries and donor-specific antibody (DSA)). In summary, the addition of tacrolimus therapy for 2 months to a steroid-free, alemtuzumab induction and sirolimus maintenance protocol limited the previously shown acute rejection development. Nevertheless, alloantibody was present in serum and/or C4d present on 1-year biopsy in half the patients. The combination of CKA and DSA monitoring or the performance of transvivo DTH correlated with immune status of the patients.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antibodies, Neoplasm/therapeutic use , Graft Rejection/prevention & control , Immunosuppressive Agents/therapeutic use , Kidney Transplantation/immunology , Sirolimus/therapeutic use , Tacrolimus/therapeutic use , Alemtuzumab , Antibodies, Monoclonal, Humanized , Antigens, CD/blood , B-Lymphocytes/drug effects , B-Lymphocytes/immunology , Drug Therapy, Combination , Female , Follow-Up Studies , Forkhead Transcription Factors/analysis , Forkhead Transcription Factors/immunology , HLA Antigens/blood , Humans , Hypersensitivity, Delayed/drug therapy , Kidney Diseases/classification , Kidney Diseases/surgery , Male , Monitoring, Immunologic/methods , White People
19.
J Laryngol Otol ; 122(1): 100-4, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17445307

ABSTRACT

A case is presented of a 36-year-old Chinese woman with a renal transplant for end-stage renal failure due to Goodpasture's syndrome. She presented with a year's history of throat discomfort and acid regurgitation into her throat. Videolaryngoscopy revealed bilateral vocal process granuloma, presumed to be due to gastroesophageal reflux. A four-week course of high dose omeprazole was prescribed. On follow up a month later, the granulomas had enlarged, and laser excision was undertaken. Histological and immunohistochemical staining was consistent with Epstein-Barr virus-associated smooth muscle tumour. This is believed to be the first reported case in the English literature of such a tumour affecting the vocal process. The aim of this paper is to present the pathogenesis, clinical behaviour and treatment of Epstein-Barr virus-associated smooth muscle tumour, and to review the literature concerning the differential diagnosis of polypoid vocal process lesions.


Subject(s)
Epstein-Barr Virus Infections/complications , Granuloma/diagnosis , Laryngeal Diseases/diagnosis , Opportunistic Infections/complications , Smooth Muscle Tumor/diagnosis , Adult , Diagnosis, Differential , Female , Humans , Kidney Transplantation/immunology , Laryngeal Neoplasms/diagnosis , Laryngeal Neoplasms/virology , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/secondary , Smooth Muscle Tumor/secondary , Smooth Muscle Tumor/virology , Tomography, X-Ray Computed , Vocal Cords
20.
Am J Transplant ; 7(2): 466-70, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17173656

ABSTRACT

Chemokine-driven accumulation of lymphocytes, mononuclear and polymorphonuclear proinflammatory cells in antigenic tissue sites is a key feature of several types of T-cell-dependent autoimmunity and transplant rejection pathology. It is now clear that the immune system expends considerable energy to control this process, exemplified by the sequential layers of regulatory cell input, both innate and adaptive, designed to prevent a classical Type IV or 'delayed-type' hypersensitivity (DTH) reaction from occurring in the visual field of the eye. Yet, despite an abundance of in vitro assays currently available to the human T-cell immunologist, none of them adequately models the human DTH response and its various control features. The theme of this article is that it is relatively easy to model the effector side of the human DTH response with xenogeneic adoptive transfer models. However, we show that in order to detect inhibition of a recall DTH in response to colocalized donor antigen (linked suppression)--a characteristic feature of peripheral tolerance to an organ transplant--both the challenge site and the immunocompetence of the mouse adoptive host are critical factors limiting the sensitivity of the trans-vivo DTH test.


Subject(s)
Antigens/administration & dosage , Hypersensitivity, Delayed/diagnosis , Hypersensitivity, Delayed/immunology , Mice, Inbred BALB C/immunology , Mice, SCID/immunology , Transplantation Immunology/immunology , Animals , Disease Models, Animal , Ear , Foot , Humans , Immunosuppression Therapy/methods , Mice , Reproducibility of Results , T-Lymphocytes, Regulatory/immunology , Transplantation , Transplantation, Heterologous/immunology
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