Characterization of the inflammatory cell infiltrate in herald patches and fully developed eruptions of pityriasis rosea

BACKGROUND

Pityriasis rosea (PR) is a common cutaneous papulosquamous disorder affecting young adults. Previous studies have suggested possibilities of a viral aetiology and the involvement of cell-mediated immunity, but these remain unproven to date.

AIM

To elucidate the possible pathomechanisms in PR by characterizing the inflammatory cellular infiltrate in herald patches and fully developed PR eruptions.

METHODS

In total, 12 biopsy specimens from 6 patients diagnosed with PR were examined. For each patient, biopsies were taken from both a herald patch and a secondary patch. Specimens were processed for histopathological examination and immunohistochemical staining with a large panel of monoclonal antibodies.

RESULTS

Histopathologically, all specimens showed epidermal changes such as parakeratosis, orthokeratosis, epidermal hyperplasia and spongiosis. Less common results included epidermal exocytosis and focal parakeratosis. In all biopsies, the dermal infiltrate of lymphocytes stained positively for monoclonal antibodies specific for T cells. The ratio of the CD4+ (helper) vs. CD8+ (cytotoxic) T cells in the dermal infiltrate was increased in most specimens. Increased staining for Langerhans cells was seen within the dermis of lesional skin. There were no marked differences found in histopathology and immunohistochemistry between the herald patch and secondary lesions. Overall, there was a lack of natural killer cell and B-cell activities in PR lesions.

CONCLUSIONS

Our results support a predominantly T-cell mediated immunity in the development of PR.

Microarray analysis of multiple candidate genes and associated plasma proteins for nephropathy secondary to type 2 diabetes among Chinese individuals

AIMS/HYPOTHESIS

Evolving research suggests that common and rare alleles jointly constitute the genetic landscape of complex disease. We studied the association between 43 pathway-related candidate genes with 'intermediate phenotype' (i.e. corresponding plasma protein) and diabetic nephropathy in a customised microarray of 1,536 SNPs.

METHODS

In this case-control study of type 2 diabetic Chinese individuals with and without diabetic nephropathy, cases (n = 545) were defined on the basis of a spot urinary albumin/creatinine ratio (ACR) > 113 mg/mmol; the value for controls (n = 503) was ACR < 3.3 mg/mmol. Genotyping was performed using Illumina GoldenGate assay.

RESULTS

No single nucleotide polymorphism (SNP) remained significant in single locus analysis after correction for multiple testing. Therefore, we explored the best approximately 1% SNPs. Of these 13 SNPs, four clustered to a 5' end NADPH oxidase homologue 4 (NOX4) haplotype (GGCC frequency = 0.776) with estimated OR for diabetic nephropathy of 2.05 (95% CI 1.04-4.06) (heterozygous) and 2.48 (1.27-4.83) (homozygous) (p = 0.0055). The haplotype was correlated with plasma Cu/Zn superoxide dismutase (SOD) concentration, suggesting increased oxidative burden. Endothelin-1 SNP (rs1476046G>A, frequency = 0.252) was correlated with plasma C-terminal pro-endothelin-1 concentrations with an estimated OR for diabetic nephropathy of (heterozygous) 1.26 (0.96-1.66) and (homozygous) 1.87 (1.13-3.12) (p = 0.0072). Nitric oxide synthase 1 (NOS1) 5' haplotype (TGTC frequency = 0.38) also revealed a suggestive association with diabetic nephropathy: heterozygous 1.26 (0.95-1.67), homozygous 1.57 (1.04-2.35) (p = 0.0073). A rare NADPH oxidase homologue 1 (NOX1)-coding non-synonymous SNP (Arg315His, frequency = 0.006) was found exclusively among cases.

CONCLUSIONS/INTERPRETATION

Our preliminary observations suggest that common haplotypes from NOX4 and endothelin-1 SNP correlated with plasma Cu/Zn SOD and C-terminal pro-endothelin-1 concentrations, respectively, and might have conferred diabetic nephropathy susceptibility. Common NOS1 and rare NOX1 variants also revealed a suggestive association with diabetic nephropathy. Future studies to validate our observation are needed.

Hypopigmented macular amyloidosis with or without hyperpigmentation

Primary cutaneous amyloidosis (PCA) is a chronic pruritic skin disorder with characteristic amyloid deposits in the papillary dermis. We report three cases of PCA, which shared common features of hypopigmentation as a predominant feature with or without reticular hyperpigmentation, no itching, adult onset and dermal papillary amyloid deposition. These cases did not conform to the usual features of PCA.

Cutaneous large B-cell lymphoma of the leg: presenting initially as mononeuritis multiplex

We report a rare case of primary B-cell lymphoma of the leg presenting with mononeuropathy multiplex. A 79-year-old Chinese woman who was being investigated for mononeuritis multiplex had an incidental finding of indurated erythematous plaques on the breast and left leg. A skin biopsy from the nodular area on the right breast showed a dense and diffuse infiltrate of atypical cells with large, round, hyperchromatic nuclei with prominent nucleoli. These atypical lymphocytes were CD20+, Bcl-2+ and Mum-1+. A diagnosis of diffuse large B-cell lymphoma, leg type involving the breast and leg with extracutaneous involvement, was made. This case highlights the importance of a full systemic and cutaneous examination in patients presenting with progressive, painful peripheral neuropathy.

Gene expression patterns during intramuscular fat development in cattle

Deposition of intramuscular fat, or "marbling," in beef cattle contributes significantly to meat quality variables, including juiciness, flavor, and tenderness. The accumulation of intramuscular fat is largely influenced by the genetic background of cattle, as well as their age and nutrition. To identify genes that can be used as early biomarkers for the prediction of marbling capacity, we studied the muscle transcriptome of 2 cattle crossbreeds with contrasting intramuscular fat content. The transcriptomes of marbling LM tissue of heifers from Wagyu x Hereford (WxH; n = 6) and Piedmontese x Hereford (PxH; n = 7) crosses were profiled by using a combination of complementary DNA microarray and quantitative reverse transcription-PCR. Five biopsies of LM were taken from each animal at approximately 3, 7, 12, 20, and 25 mo from birth. Tissue was also collected from the LM of each animal at slaughter (approximately 30 mo). Microarray experiments, conducted on the first 3 biopsies of 2 animals from each crossbreed, identified 97 differentially expressed genes. The gene expression results indicated that the LM transcriptome of animals with high marbling potential (WxH) could be reliably distinguished from less marbled animals (PxH) when the animals were as young as 7 mo of age. At this early age, one cannot reliably determine meaningful differences in intramuscular fat deposition. We observed greater expression of a set of adipogenesis- and lipogenesis-related genes in the LM of young WxH animals compared with their PxH contemporaries. In contrast, genes highly expressed in PxH animals were associated with mitochondrial oxidative activity. Further quantitative reverse transcription-PCR experiments revealed that the messenger RNA of 6 of the lipogenesis-related genes also peaked at the age of 20 to 25 mo in WxH animals. The messenger RNA expression of ADIPOQ, SCD, and THRSP was highly correlated with intramuscular fat content of an individual in WxH animals. Our study provides clear evidence of early molecular changes associated with marbling and also identifies specific time frames when intramuscular fat development in cattle muscle can be detected by using gene expression. This information could be used by animal scientists to design optimal nutrition for high marbling potential. In addition, the genes found to be highly expressed during development of marbling could be used to develop genetic markers or biomarkers to assist with beef production strategies.

Comparison of nested-polymerase chain reaction and virus culture for the diagnosis of genital herpes simplex virus infection

INTRODUCTION

This study was performed to compare nested-polymerase chain reaction (PCR) with viral culture as a diagnostic tool for genital herpes simplex virus (HSV) infection in a sexually transmitted infection (STI) clinic in Singapore.

METHODS

103 consecutive patients presenting with clinical features suggestive of genital herpes were enrolled in the study. Two swabs were obtained from each patient. On one swab, cell culture and typing was performed, and on the second swab, nested-PCR was performed and the infecting viral type was determined by using type-specific primers.

RESULTS

63 patients (61.2 percent) had a positive PCR test for HSV. Of these, 13 patients (20.6 percent) had HSV type 1 (HSV-1), 50 patients (79.4 percent) had HSV type 2 (HSV-2). HSV-1 and HSV-2 were detected by viral culture in only six patients and 24 patients, respectively. The sensitivity of cell culture compared to PCR was 46.1 percent for HSV-1 infection and 48 percent for HSV-2 infection. PCR further detected an additional 52.4 percent of HSV cases. The specificity of PCR was 100 percent.

CONCLUSION

Nested-PCR has been shown in this study to be an effective diagnostic and typing method for HSV infection in a STI clinic in Singapore with its higher sensitivity and specificity to routine viral isolation in cell culture.

Characterization of AFLP markers associated with growth in the Kuruma prawn, Marsupenaeus japonicus, and identification of a candidate gene

Growth rate of the Kuruma prawn, Marsupenaeus japonicus is an important economic trait, with larger animals commanding higher market prices. To identify gene markers associated with growth, a genetic map of a full-sib F(2) intercross family of M. japonicus has previously been generated and quantitative trait loci (QTL) influencing weight, total length, and carapace length were identified. In this study, amplified fragment length polymorphism (AFLP) markers associated with the major QTL region, contributing 16% to phenotypic variation, were characterized. Flanking sequence has been obtained and allelic variants responsible for segregation patterns of these markers have been identified. The genomic sequence surrounding the AFLP band 7.21a, residing under the QTL peak, contains a gene sequence homologous to the elongation of very long chain fatty acids-like (ELOVL) protein family. A full-length mRNA (ELOVL-MJ) encoding this protein was isolated from M. japonicus, representing both the first ELOVL gene in crustacea and the first candidate gene identified via QTL studies in crustacea.

Cutaneous phaeohyphomycosis due to Cladophialophora bantiana in an immunocompetent patient

We report the case of a 56-year-old Chinese woman with phaeohyphomycosis. She presented with a 4-year history of a recurring erythematous plague initially diagnosed as chromoblastomycosis on histopathological examination. Surgical excision was performed when the lesion recurred despite intial treatment response to itraconazole. Tissue cultures of the surgical specimen grew Cladophialophora bantiana. Treatment with terbinaffine post surgery was instituted with no recurrence of the lesion to date. Cutaneous phaeohyphomycosis caused by Cladophialophora bantiana is rare and this case highlights the clinical presentation, laboratory findings and treatment of this infection.

Trapezoid rotational bone graft osteotomy for metacarpal and phalangeal fracture malunion

Metacarpal and phalangeal fracture malunions with significant angulation deformity are associated with bone shortening, prominence of the metacarpal head in the palm or pseudoclaw deformity and may be symptomatic. If so, they may need corrective osteotomy procedures. Conventional methods of closing, or opening, wedge osteotomy do not restore the length of the bone exactly. Simultaneous correction of the angular deformity and restoration of bone length can be addressed by a trapezoid rotational bone graft osteotomy. A double osteotomy is done and the segment of bone is rotated and re-inserted as a bone graft. This was done successfully in four metacarpal and two phalangeal fracture malunions with angulation deformities.

Anencephaly in Singapore: a ten-year series 1993-2002

INTRODUCTION

Anencephaly is a neural tube defect that is incompatible with life. Previous studies have suggested that there is a racial predilection for this condition. However, local studies have not shown a statistical difference between the races. The aim of this study is to examine the incidence and the demographical trend of this condition over a ten-year period.

METHODS

Data of patients with anencephaly born from 1993 to 2002 were retrieved from the National Birth Defect Registry and analysed.

RESULTS

There were a total of 267 cases of anencephaly in the ten-year period from 1993 to 2002, giving an overall incidence of 0.58 per 1,000 livebirths, with a decreasing trend noted. The incidence was highest among the Malay population, compared with the Chinese population (p-value equals 0.03) and other races. Abortion rates have also increased over the years, causing a reduction in livebirth rates for this condition.

CONCLUSION

The overall incidence and birth incidence of anencephaly has seen a decreasing trend over the last ten years, with the latter being contributed significantly by early termination. More studies should be done to ascertain if improved folate supplementation has contributed to the drop in overall incidence. The incidence in the Malay population is significantly higher than other races and this phenomenon should be further examined.

Joint analysis of multiple cDNA microarray studies via multivariate mixed models applied to genetic improvement of beef cattle

In functional genomic laboratories, it is common to use the same microarray slide across studies, each investigating a unique biological question, and each analyzed separately due to computational limitations and/or because there is no hybridization of samples from different studies on one slide. However, the question of analyzing data from multiple studies is a major current issue in microarray data analysis because there are gains to be made in the accuracy of estimated effects by exploiting a covariance structure between gene expression data across studies. We propose an approach for combining multiple studies using multivariate mixed models, with the assumption of a nonzero correlation among genes across experiments, while imposing a null residual covariance. We applied this method to jointly analyze three experiments in genetics of cattle with a total of 54 arrays, each with 19,200 spots and 7,638 elements. The resulting seven-variate model contains 752,476 equations and 56 covariances. To identify differentially expressed genes, we applied model-based clustering to a linear combination of the random gene x variety interaction effect. We enhanced the biological interpretation of the results by applying an iterative algorithm to identify the gene ontology classes that significantly changed in each experiment. We found 118 elements with coordinate expression that clustered into distinct biological functions such as adipogenesis and protein turnover. These results contribute to our understanding of the mechanistic processes involved in adipogenesis and nutrient partitioning.

Cerclage-wiring-assisted fixation of difficult hand fractures

Difficult hand fractures with multiple butterfly fragments, multiple cortical splits or intraarticular extension continue to pose a challenge for optimal stable fixation that allows early postoperative mobilisation. In this study, we describe the use of cerclage-wire-assisted fixation of 17 difficult hand fractures in 16 patients. The cerclage wires helped to maintain the reduction, so providing sufficient initial stability for placement of a plate and screws. Stable fixation of the fracture was then accomplished without losing the reduction. One to three cerclages of stainless-steel wires were used for the preliminary fixation. Stable fixation was then accomplished by a bridging or neutralising plate technique. Postoperatively, the fixation was sufficiently stable to allow immediate mobilisation. With an average follow up of 44.5 months, all 17 fractures united without loss of reduction. At final follow-up, the average total active range of motion was 247 degrees (range 220-260 degrees ).

RUNX3 protein is overexpressed in human basal cell carcinomas

Basal cell carcinomas (BCC), which are the most common form of skin malignancy, are invariably associated with the deregulation of the Sonic Hedgehog (Shh) signalling pathway. As such, BCC represent a unique model for the study of interactions of the Shh pathway with other genes and pathways. We constructed a tissue microarray (TMA) of 75 paired BCC and normal skin and analysed the expression of beta-catenin and RUNX3, nuclear effectors of the wingless-Int (Wnt) and bone morphogenetic protein/transforming growth factor-beta pathways, respectively. In line with previous reports, we observed varying subcellular expression pattern of beta-catenin in BCC, with 31 cases (41%) showing nuclear accumulation. In contrast, all the BCC cases tested by the TMA showed RUNX3 protein uniformly overexpressed in the nuclei of the cancer cells. Analysis by Western blotting and DNA sequencing indicates that the overexpressed protein is normal and full-length, containing no mutation in the coding region, implicating RUNX3 as an oncogene in certain human cancers. Our results indicate that although the deregulation of Wnt signalling could contribute to the pathogenesis of a subset of BCC, RUNX3 appears to be a universal downstream mediator of a constitutively active Shh pathway in BCC.

Squamous cell carcinoma developing in two Chinese patients with chronic discoid lupus erythematosus: the need for continued surveillance

Squamous cell carcinoma (SCC) is a rare late sequel of chronic discoid lupus erythematosus (CDLE). We report two cases of SCC developing in Chinese patients with CDLE. The first patient had prior biopsies from the same site that showed viral warts and the second patient had multiple histologically confirmed viral warts around the vicinity of the previously excised SCC. In this paper, we emphasize the need to be suspicious of warty lesions on skin afflicted by CDLE, and repeat biopsies should be performed if there is failure to respond to conventional therapy.

Neurothekeomas of the upper limb--case series and clinicopathological review

Neurothekeomas are rare, benign soft tissue tumours that are considered to be of nerve sheath origin. We present a case series of three patients who have neurothekeomas of the upper limb. There was a remarkably high tumour recurrence rate. The factors contributing to this outcome were studied and a clinicopathological review was performed.

Gene expression-based approaches to beef quality research

Advances in mammalian genomics have permitted the application of gene expression profiling approaches to gene discovery for meat quality traits in cattle. The first custom cDNA microarray based on the transcriptome of bovine muscle and fat tissue was developed and applied to animal experimentation and cell culture experimentation between 1999 and 2005. Complementary DNA microarray tools for beef quality research were developed in parallel with bioinformatics tools that permit the analysis of microarray data obtained from complex experimental designs commonly encountered in large animal research. In addition, tools were designed to link gene expression data with gene function in the bovine, such as in vitro models of bovine adipogenesis and bioinformatics tools to map gene networks from expression data. The application of these genomics tools to the study of beef quality has yielded novel knowledge of genes and molecules involved in the processes of intramuscular adipogenesis and protein turnover. This review summarises the current state of knowledge and important lessons derived from bovine genomics initiatives in Australia and around the world.

Reticulate hyperpigmented scleroderma: a new pigmentary manifestation

Scleroderma is a systemic disease with a myriad of cutaneous manifestations. Pigmentary disturbances have been described in scleroderma. While diffuse generalized hyperpigmentation and localized hypopigmentation with perifollicular hyper-pigmentation are well recognized, a vascular induced hyperpigmentation has only been recently described. In this paper, we report another unrecognized pigmentary abnormality in a 48-year-old patient who presented with a reticulate hyper-pigmentation affecting the trunk, upper and lower limbs. To our knowledge, cutaneous hyperpigmented reticulate scleroderma has not been reported previously.

The prevention of neuroma formation by diathermy: an experimental study in the rat common peroneal nerve

INTRODUCTION

There have been anecdotal reports of the efficacy of diathermy (electrocoagulation) in the prevention of neuroma formation. However, this has not been investigated in the laboratory. In this experiment involving 40 rats, diathermy was applied to the terminal proximal ends of transected rat common peroneal nerves to evaluate its effect on neuroma formation.

MATERIALS AND METHODS

Monopolar and bipolar diathermy set at 45 W, applied for different durations (4 seconds and 10 seconds), were evaluated. Under histological control, the presence of neuroma formation and the diameter of the nerve ends were evaluated at 3 months. The contralateral common peroneal nerve in the same rat served as the control. The dorsal root ganglia of 2 rats in each group were also harvested for histological study.

RESULTS

The incidence of neuroma formation was 30% in the group which received high-duration monopolar diathermy (10-second application), versus 90% in the control group (P <0.05). The mean diameter of the nerve ends was smaller at 0.51 mm [standard deviation (SD), 0.29] versus 0.85 mm (SD, 0.24) in the control (P <0.05). The incidence of neuroma formation was 30% in the group which received low-duration monopolar diathermy (4-second application), and 83% in the control group (P <0.05). The diameter was 0.43 mm (SD, 0.14) versus 0.85 mm (SD, 0.28) (P <0.05). High-duration bipolar diathermy applied for 10 seconds, showed a neuroma formation of 25% versus 100% in the control group (P <0.05). The diameter of the nerve ends was 0.48 mm (SD, 0.07) versus 0.79 mm (SD, 0.36) in the control group (P <0.05). The incidence of neuroma formation was 60% in the low-duration bipolar group, which received bipolar diathermy application for 4 seconds, and 90% in the control group (P = 0.25). The diameter of the nerve ends in the low-duration bipolar group was 0.52 mm (SD, 0.24) versus 0.76 mm (SD, 0.40). The incidence of neuroma formation and the difference in diameter in the low duration-bipolar group were both not statistically significant.

CONCLUSION

This study demonstrates the effectiveness of monopolar diathermy in reducing the rate of neuroma formation. For bipolar diathermy, an application of 10 seconds was effective in reducing neuroma formation but an application of 4 seconds was not associated with a significant reduction in neuroma formation.

Motor root conduction block in traumatic brachial plexopathy

A 31-year old man sustained severe left brachial plexus traction injury. Electrical stimulation demonstrated multilevel motor root conduction block, which reversed after a 4-month period. Motor root conduction studies are useful diagnostic and prognostic adjuncts in the management of brachial plexopathy.

Lymphocytic gastritis-like T cell lymphoma: molecular evidence of an unusual recurrence

This report describes a patient with a gastric biopsy specimen showing histomorphological and immunohistochemical appearances indistinguishable from those usually present in lymphocytic gastritis, a rare condition of unknown aetiology with a distinctive phenotype. The patient had a history of a biopsy confirmed T cell non-Hodgkin lymphoma at two anatomical sites (bladder and stomach), which was subsequently treated. Molecular analysis of the T cell receptor (TCR) gamma chain gene rearrangements showed a distinct monoclonal T cell population in the bladder and gastric biopsies. The same analysis in the lymphocytic gastritis-like biopsy sample showed a monoclonal population with identical base pair size to that identified in the other specimens. This report highlights the importance of TCR gene rearrangement analysis in the diagnosis of unusual gastric inflammation, and the use of capillary electrophoresis based polymerase chain reaction in the follow up of lymphoproliferative disorders.