Detection of interleukin-1 and interleukin-6 in adult rat brain, following mechanical injury, by in vivo microdialysis: evidence of a role for microglia in cytokine production

In vivo levels of interleukin-1 (IL-1) and IL-6, present in the interstitial spaces of brain, have been repeatedly monitored up to 7 days after insertion of a microdialysis probe, designed to induce mechanical trauma to the brain. IL-1 is barely detectable immediately after implantation but over a 24-48 h period a 15-fold increase is seen. In contrast IL-6 levels at day 0 are high, increasing slightly (10%) by day 1 but decreasing to 40% by day 2. The temporal pattern of IL-6 recovery in the cerebrospinal fluid was similar to that in the dialysate but the levels were significantly lower and may reflect diffusion from the site of the probe lesion. Cellular sources of these cytokines include macrophages and neutrophils, which have infiltrated the lesion and microglia resident in the brain, which can be identified at the lesion site within 24 h of probe implantation. The astrocytic response to injury, evidenced by increased glial fibrillary acidic protein staining occurs much later, by day 7, and is unlikely to be responsible for IL-1 and IL-6 production found at 24-48 h. Since upon isolation and stimulation of microglia in vitro with lipopolysaccharide IL-1 and IL-6 can be measured in the supernatant, it would appear that they have the capacity to produce cytokines in vivo. Localised synthesis of cytokines at sites of brain injury by microglia would further stimulate microglia in an autocrine manner and also propagate the astrocytic reaction.     

Combined laparoscopic and perineal approach for the management of recurrent tailgut cyst

Tailgut cyst is an uncommon developmental anomaly arising from the embryonic hindgut in the retrorectal space. The patient frequently is asymptomatic or has vague perineal complaints that pose a diagnostic dilemma. Moreover, the patient is often misdiagnosed and therefore mismanaged. MRI is the investigation of choice for diagnosis. After the diagnosis is established, complete surgical excision is required to alleviate patient discomfort and to prevent complications such as infection, malignant transformation, and recurrence. Proper clinical examination and imaging not only establish the accurate diagnosis but also help in determining the best surgical approach for the patient (anterior abdominal, posterior sacral perineal, or combined approach). We hereby report a case of recurrent tailgut cyst managed with a combined anterior laparoscopic and perineal approach.     

Folie a deux and delusional disorder by proxy: an atypical presentation

Delusion of parasitosis is a rare condition characterised by an individual harbouring the delusion of being infested with insects or parasites. We report a rare and interesting case of delusion of parasitosis presenting as folie a deux, that is, the delusion is shared by both the parents of an 18‐month‐old child, with proxy projection of parental delusion on the child. The case highlights the rare concomitant occurrence of two psychocutaneous disorders and emphasizes the importance of early recognition and appropriate intervention to safeguard the well‐being of the child.     

Mice deficient in biglycan and fibromodulin as a model for temporomandibular joint osteoarthritis

The temporomandibular joint (TMJ) within the craniofacial complex is unique. In humans, the TMJ can become diseased resulting in severe and disabling pain. There are no cures for TMJ disease at this time. Animal models of TMJ disease are scarce, but some exist, and they are described in this paper. We present in greater detail one animal model that is deficient in two extracellular matrix (ECM) proteoglycans, biglycan (BGN) and fibromodulin (FMOD). Doubly deficient BGN/FMOD mice develop premature TMJ osteoarthritis (OA). In order to explore the mechanistic basis of TMJ-OA, tissues from the condyle of mutant mice were examined for their relative capacity to differentiate and undergo apoptosis. Our data show that there is a redistribution of the critical ECM protein, type II collagen, in mutant mice compared with controls. Mutant mice also have increased apoptosis of the chondrocytes embedded in the articular cartilage. We speculate that the overall imbalance in apoptosis may be the cellular basis for the abnormal production of structural ECM proteins. The abnormal production of the ECM could, in turn, lead to premature erosion and degradation of the articular surface resulting in TMJ-OA. These data underscore the importance of the ECM in controlling the structural integrity of the TMJ.     

Limited capacity of the nuclear matrix to bind telomere repeat binding factor TRF1 may restrict the proliferation of mortal human fibroblasts

The maintenance of telomere integrity is essential for prolonged cell proliferation, and failure in this mechanism is a most consistent manifestation of cellular senescence. In this study, we investigated the role of telomere repeat binding factor (TRF1) in the proliferation of human fibroblasts. TRF1 expression is upregulated in a large variety of immortal human cells and supports de novo telomere formation in a dose-dependent manner. These observations suggest that the suppression of TRF1 might limit telomere maintenance and thus the life span of mortal cells. However, primary fibroblasts ectopically overexpressing TRF1 were unable to avoid senescence. On the other hand, exogenously expressed TRF1 in primary fibroblasts neither supported de novo telomere formation nor bound to the nuclear matrix as tightly as observed in immortal cells that show upregulated TRF1 expression. We present evidence suggesting that mortal human cells lack specific ligand(s) that anchor TRF1 to the nuclear matrix and that this contributes to their limited lifespan.     

Association of TNF-beta polymorphism with disease severity among patients infected with hepatitis C virus

The pathogenesis of chronic hepatitis C virus (HCV) infection remains unclear. Tumour necrosis factor alpha (TNF-alpha) is alleged to contribute in the pathogenesis of chronic HCV infection. Single nucleotide polymorphism in TNF-alpha and -beta genes could influence the outcome of HCV infection. The aim was to study single nucleotide polymorphism in TNF-alpha promoter region and Nco I polymorphisms in the TNF-beta gene in patients with chronic hepatitis C. Fifty-two patients with histologically proven chronic hepatitis, who had raised ALT levels (>1.5 x ULN) and were HCV RNA positive, were studied. Genotyping of -308 promoter variant of TNF-alpha was performed by PCR with primers that incorporated an Nco I restriction site. For PCR typing of the TNF-beta Nco I restriction fragment length polymorphism, sequence specific primers were used. Polymorphism in the TNF-alpha G/G, G/A and A/A allele was not different between HCV patients and healthy controls. TNF-beta A/A allele was significantly more common (P = 0.02) in patients (28.8%) as compared to controls (12.8%), whereas no significant difference was observed for TNF-beta G/A and G/G alleles [corrected]. Nco I TNF-beta A/A was strongly associated with -308 TNF-alpha G/G (RR of HCV persistence = 4.9), indicating possible linkage between TNF-beta A/A and TNF-alpha G/G allele. Patients with severe hepatic fibrosis more frequently had the TNF-beta A/A allele as compared to patients with mild disease (P = 0.04). Immunogenetic factors, such as single nucleotide polymorphisms in TNF-beta (A/A allele), may affect the natural course of HCV infection, in particular, the disease progression. Larger studies including cytokine expression profiles are needed to fully understand the contribution of the polymorphisms described in the pathogenesis of chronic hepatitis C.     

The use of immunohistochemistry in the diagnosis of metastatic clear cell renal cell carcinoma: a review of PAX-8, PAX-2, hKIM-1, RCCma, and CD10

The diagnosis of metastatic clear cell renal cell carcinoma may be difficult in some cases, particularly in the small image-guided biopsies that are becoming more common. As targeted therapies for renal cell carcinoma are now standard treatment, the recognition and diagnosis of renal cell carcinoma has become even more critical. Many adjunctive immunohistochemical markers of renal epithelial lineage such as CD10 and RCCma have been proposed as aids in the diagnosis of metastatic renal cell carcinoma, but low specificities often limit their utility. More recently described markers (PAX-2, PAX-8, human kidney injury molecule-1, hepatocyte nuclear factor-1-β, and carbonic anhydrase-IX) offer the potential for greater sensitivity and specificity in this diagnostic setting; however, knowledge of their expected staining in other neoplasms and tissues is critical for appropriate use. In this review, we discuss the most widely used immunohistochemical markers of renal lineage with an emphasis on their sensitivity and specificity for metastatic clear cell renal cell carcinoma. Subsequently, we present a variety of organ-specific differential diagnostic scenarios in which metastatic clear cell renal cell carcinoma might be considered and we propose immunopanels for use in each situation.