Design of a tunable bacterial gene expression system using engineered σ factors.

Extracytoplasmic function (ECF) σ factors selectively upregulate expression of specific genes in bacteria. These σ factors, belonging to the σ70 family, are much smaller than the primary, housekeeping σ factor with two helical domains that interact with the Pribnow box and the -35 element of the promoter DNA. Structural studies reveal that promoter specificity in a σ factor is determined by the interactions between a loop (L3) and the Pribnow box element. Similarly, the efficiency of transcription initiation is governed by the polypeptide linker between the two promoter-binding domains. Both these polypeptide segments are dynamic and poorly conserved among ECF σ factor homologs. This feature hitherto limited insights from protein-DNA interactions to be correlated with transcription initiation efficiency. Here, we describe an approach to characterize these features that govern the dynamic range of gene expression using chimeric Escherichia coli σE. The L3 loop and linker polypeptides in these σE chimeras were replaced by the corresponding segments from 10 annotated and functional Mycobacterium tuberculosis ECF σ's. In vitro and in vivo measurements to determine the effect of these polypeptide replacements provided an experimentally validated σE chimera- gene expression level data set. We illustrate the utility of this chimeric σE library in improving the efficiency of a biosynthetic pathway in E. coli. In a two-enzyme step, unaffected by feedback inhibition and substrate concentration, we show an increase in desired product levels by altering the relative intracellular levels of the target enzymes using this library of σ factors. The chimeric σE library thus demonstrates the feasibility of engineering σ factors to achieve bespoke expression levels of target genes for diverse applications in synthetic microbiology. IMPORTANCE: The synthesis of organic compounds involves the action of multiple enzymes in a biosynthetic pathway. Incorporating such biosynthetic pathways into microbes often leads to substantial cellular and metabolic stress resulting in low titers of the target compound. This limitation can be offset, in part, by optimizing enzyme efficiency and cellular enzyme concentration. The former involves significant efforts to achieve improvements in catalytic efficiency with the caveat that the metabolic load on a microbial cell imposed by the overexpression of the exogenous enzyme could result in reduced cell fitness. Here, we demonstrate the feasibility of engineered σ factors to modulate gene expression levels without significant genetic engineering. We note that changing the sequence of two flexible polypeptide loops without any changes to the structural scaffold of the transcription initiation factor σE could modulate the expression levels of the target genes. This ability provides a route to improve the efficiency of a biosynthetic pathway without altering the overall genomic makeup. The σE chimera library thus provides an avenue for pre-determined conditional gene expression of specific genes in Escherichia coli.

Positional preferences in flavonoids for inhibition of ribonuclease A: Where "OH" where?

Flavonoids are a class of polyphenols that possess diverse properties. The structure-activity relationship of certain flavonoids and resveratrol with ribonuclease A (RNase A) has been investigated. The selected flavonoids have a similar skeleton and the positional preferences of the phenolic moieties toward inhibition of the catalytic activity of RNase A have been studied. The results obtained for RNase A inhibition by flavonoids suggest that the planarity of the molecules is necessary for effective inhibitory potency. Agarose gel electrophoresis and precipitation assay experiments along with kinetic studies reveal Ki values for the various flavonoids in the micromolar range. Minor secondary structural changes of RNase A were observed after interaction with the flavonoids. An insight into the specific amino acid involvement in the binding of the substrate using docking studies is also presented. The dipole moment of the flavonoids that depends on the orientation of the hydroxyl groups in the molecule bears direct correlation with the inhibitory potency against RNase A. The direct association of this molecular property with enzyme inhibition can be exploited for the design and development of inhibitors of proteins.

Evaluation of the Graft Kidney in the Early Postoperative Period: Performance of Contrast-Enhanced Ultrasound and Additional Ultrasound Parameters.

OBJECTIVES: To evaluate the various quantitative parameters of Doppler ultrasound, contrast-enhanced ultrasound (CEUS), and shear wave elastography (SWE) of graft kidneys in the early postoperative period and to explore their utility in the diagnosis of parenchymal causes of graft dysfunction. METHODS: In this ethically approved study, consecutive patients who underwent renal transplantation from March 2017 to August 2018 were recruited, and those with urologic or vascular complications and those who denied consent were excluded. All patients underwent ultrasound with Doppler, SWE, CEUS (using sulfur hexafluoride), and renal scintigraphic examinations 3 to 10 days after transplantation. A composite reference standard was used, including the clinical course, renal function test results, urine output, and histopathologic results for graft dysfunction. Cortical SWE values, quantitative CEUS parameters (generated from a time-intensity curve), and their ratios were analyzed to identify graft dysfunction and differentiate acute tubular necrosis (ATN) from acute rejection (AR). RESULTS: Of the 105 patients included, 19 developed graft dysfunction (18.1%; 12 ATN, 5 AR, and 2 drug toxicity) in the early postoperative period. The peak systolic velocity in the interpolar artery showed a significant difference between control and graft dysfunction groups (P < .001) as well as between ATN and AR (P = .019). Resistive indices and SWE did not show significant differences. Ratios of the time to peak showed a significant difference between control and graft dysfunction groups (P < .05). The rise time and fall time of the large subcapsular region of interest and the rise time ratio were significantly different between ATN and AR (P = .03). CONCLUSIONS: Contrast-enhanced ultrasound can be used to diagnose parenchymal causes of early graft dysfunction with reasonable diagnostic accuracy.

Spectrum of biopsy-proven renal disease in northern India: A single-centre study.

AIM: Pattern of kidney diseases varies across geographies due to multiple factors. There is a paucity of information from South Asia due to the absence of nationwide/regional biopsy registries. This study aimed to delineate the spectrum of renal parenchymal diseases in our region. METHODS: Records of kidney biopsies done in our nephrology department between 2006 and 2016 were analysed. Clinico-pathological correlation was done from the available records. RESULTS: Of the 3275 biopsy evaluated, 61.9% were males, and mean age was 33.2 ± 14.2 years. 6.2% patients were elderly (age ≥ 60 years). Nephrotic syndrome (60.3%) was the commonest indication for biopsy. On histology, 73.0% patients had primary glomerulonephritis (GN), 15.5% secondary GN, 5.3% tubulo-interstitial and 3.7% vascular disease. Focal segmental glomerulosclerosis (FSGS) was the commonest primary GN accounting for 18.2% of all GNs, followed by minimal change disease (16.8%), membranous nephropathy (MN) (16.0%) and IgA nephropathy (10.4%). Lupus nephritis (10.6%) and amyloidosis (3.7%) were the commonest secondary GN. The commonest cause of nephrotic syndrome was minimal change disease (22.9%), acute nephritic syndrome was lupus nephritis (30.6%), rapidly progressive renal failure was pauci-immune crescentic GN (24.5%). IgA nephropathy was the commonest etiology of asymptomatic urinary abnormalities (26.3%) and gross haematuria (50%). About 60.9% patients of undetermined chronic kidney disease had glomerular diseases, and 13.6% had chronic tubulointerstitial nephritis. Lupus nephritis and acute cortical necrosis were significantly more common in females compared with males. CONCLUSION: This is one of the largest cohorts of kidney biopsies from India, and it delineates the unique features and differences in the pattern of kidney disease in our population.

Role of miRNA-182 and miRNA-187 as potential biomarkers in prostate cancer and its correlation with the staging of prostate cancer.

PURPOSE: The microRNAs expression has emerged as a potential biomarker for the diagnosis and prognosis of prostate cancer. This study investigated the expression of miRNA-182 and miRNA-187 in prostate cancer patients and established a correlation between miRNA expression and staging of prostate cancer. MATERIALS AND METHODS: This prospective observational study involved patients undergoing transrectal ultrasound-guided biopsy for suspicion of prostate cancer. Pre-biopsy urine samples and prostatic core tissue samples of the patients were preserved and the miRNA-182 and miRNA-187 were studied. RESULTS: Sixty-three patients were included in this study, thirty-three patients were diagnosed with prostate cancer and thirty patients having benign histopathology were considered as controls. The expression of miRNA-182 was significantly increased (p=0.002) and miRNA-187 significantly decreased (p<0.001) in prostate cancer tissue specimens. However, the expression of these miRNAs did not significantly differ in the urine of prostate cancer patients as compared to controls. Serum Prostatic Specific Antigen (PSA) inversely correlated with the median expression of miR-187 in prostatic tissue (p=0.002). Further, the expression of miRNA-187 in prostate cancer tissue was significantly decreased in metastatic prostate cancer (p=0.037). Using ROC analysis, miRNA-187 expression was able to distinguish the presence or absence of bone metastasis [area under ROC (AUROC) (±SD) was 0.873±0.061, p<0.001]. CONCLUSION: The miRNA-182 and miRNA-187 appear to be promising biomarkers in prostate cancer and miRNA-187 can serve as an important diagnostic marker of metastatic prostate cancer.

Urinary prostate-specific antigen and microseminoprotein-beta levels in men with and without prostate cancer: A prospective cohort study.

INTRODUCTION: The role of urinary proteomics in the diagnosis of prostate cancer (PCa) is undefined. Levels of urinary biomarkers such as prostate-specific antigen (PSA) and microseminoprotein-beta (MSMB) may differ between men with and without PCa. We tested this hypothesis using urine samples before and after digital rectal examination (DRE) in men with an indication for prostate biopsy. MATERIALS AND METHODS: In an institutional ethics committee approved prospective cohort study, men with elevated PSA or a nodule on DRE underwent a pre- and post-DRE urine sample examination for urinary PSA and MSMB levels. Levels were compared between men who had PCa diagnosed on biopsy (Group A) and those with a negative biopsy (Group B). RESULTS: Seventy-seven patients were recruited of whom 32 had PCa (Group A) and 45 had no cancer (Group B) on biopsy. The median (interquartile range) serum PSA was 49.6 (0.2-254) ng/ml. The median urine PSA (29.5 vs. 26.4 mg/dl) and MSMB (1.7 vs. 2.4 mg/dl) were similar in both groups at baseline. However, post-DRE, both these metabolites rose in Group B but not in Group A, resulting in significantly higher post-to-pre values in Group B versus Group A. The post-DRE urine PSA/MSMB ratio was also significantly different between the groups. CONCLUSIONS: Urinary PSA and MSMB rose significantly after DRE only in men without PCa. Post-DRE urine PSA, MSMB, and PSA/MSMB ratio can differentiate PCa from benign pathology in men with an indication for prostate biopsy.

Mangiferin attenuates cisplatin-induced acute kidney injury in rats mediating modulation of MAPK pathway.

Cisplatin has been confined due to the reported cases of nephrotoxicity. In the present study, an active xanthone, Mangiferin (from Mangifera indica) was investigated for its defensive role in cisplatin-induced nephrotoxicity. Male wistar albino rats were divided into six groups i.e., group 1 (normal); group 2 (cisplatin control); group 3, 4, and 5 (mangiferin 10, 20, and 40 mg/kg, i.p.); and per se (40 mg/kg; i.p.). The treatment was given for 10 days. On day 7, single dose of cisplatin 8 mg/kg i.p. was administered to induce nephrotoxicity in all groups except normal and per se. On day 11, animals were anesthetized, blood was taken from heart and serum was separated. Thereafter, rats were sacrificed and kidneys were isolated and preserved for histopathological, ultrastructural, immunohistochemical, and western blot analysis. Cisplatin control group showed significant impairment in renal function due to increased inflammation and oxidative stress which was also confirmed by histopathology and MAPK pathway proteins expression. However, pretreatment with mangiferin 20 and 40 mg/kg significantly reversed the renal function along with the structural changes and the levels of antioxidants. Mangiferin treatment attenuated DNA damage and apoptotic pathway.

Biosafety of unmodified ultrafine gold particles (AuPs) upon interacting with human blood components before systemic use.

Ultrafine gold particles (AuPs) can be emerged as a good candidate in the field of drug delivery as well as in imaging applications. However, little attention has been paid to detailed study of nanoparticle's interaction with blood components before systemic use. An investigation into the interaction of ultrafine AuPs with blood components is must for its clinical application. In present study, the interaction of ultrafine sized AuPs (2 ±â€¯0.5 nm, 5 ±â€¯1 nm, and 10 ±â€¯2 nm) with blood components and its immunogenic property (pro-inflammatory reaction) was investigated. All three sized AuPs did not cause any significant hemolysis. Plasma coagulation study showed significant increase in Prothrombin time (PT) with International Normalized Ratio (INR) value raised to 1.53 with 10 nm AuPs. Maximum prolongation of activated partial thromboplastin time (APTT) (3.2 s) was seen with 5 &10 nm sized AuPs. Maximum thrombin time (TT) prolongation was seen with 2 nm (18.3s) with the difference of 1.4 s as compared to control. Platelet aggregation was faster in case of 5 & 10 nm sized AuPs. All three sized AuPs exhibited in-vitro C3 complement activation whereas they did not stimulate significant proliferation of peripheral blood mononuclear cells (PBMC). These findings further validate the utility of ultrafine AuPs for in-vivo applications.

Leishmania donovani reduces the levels of retinoic acid-synthesizing enzymes in infected macrophages and favoring its own survival.

People suffering from malnutrition become susceptible to the infection like Leishmania sp., as it results in a compromised immune response. Retinoic acid (RA), an important constituent of nutrition, shows an immune-modulatory activity. However, its role in the containment of infection is not yet ascertained, particularly in case of visceral leishmaniasis (VL). VL patients (n = 10) and healthy endemic controls (n = 9) were recruited to measure the serum levels of RA. An in vitro model of Leishmania infection using the murine mφ cell line J774.1 was used to investigate the RA-synthesizing enzymes (RALDH-1 and RALDH-2). Parasite loads among infected mφ were measured by quantitative expression of kDNA in the presence of an inhibitor of the RALDH-2 enzyme. We found a significant decrease in the serum levels of RA in VL cases. Importantly, we observed decreased levels of RALDH-1 and RALDH-2 among L. donovani-infected mφ along with simultaneous decrease as well as increase in the Th-1 and Th-2-associated factors, respectively. Furthermore, the pretreatment of mφ with an RALDH-2 inhibitor improved parasite in vitro infection. Our findings show impaired RA pathway among infected mφ and indicate that an intact RA pathway is critical for anti-Leishmania immune response. Graphical abstract ᅟ.

BK polyomavirus and urothelial carcinoma: Experience at a tertiary care centre in India with review of literature.

INTRODUCTION: BK polyomavirus is ubiquitous and remains dormant in the urothelial tract, reactivating and replicating in the immunocompromised state especially in the setting of post-renal transplantation where it is believed to be directly oncogenic based on recent reports. Its oncogenic role in the immunocompetent host is controversial. This study aimed to investigate the association of BK polyomavirus in Urothelial Carcinoma. MATERIAL AND METHODS: Patients with suspected urothelial carcinoma (UC) admitted under Department of Urology over a period of one year were recruited and transuretheral bladder tumor (TURBT) resection was performed, along with sampling of cystoscopically normal-appearing urothelium away from the tumor. In addition, cystectomy specimens with UC were included, with sampling of grossly normal-appearing urothelium away from the tumor. Immunohistochemistry (IHC) for SV40 T-Antigen and chromogenic in situ hybridization (CISH) using BK polyomavirus specific probe was performed on the paired samples (tumor and normal). RESULTS: Twenty-three TURBT and 14 cystectomy specimens were assessed. None of the cases showed evidence of BK polyomavirus infection in tumor or in surrounding mucosa by IHC. CISH performed in ten cases were also found to be negative. In comparison, one post-renal transplant urothelial carcinoma in our experience showed diffuse SV40 staining. CONCLUSIONS: This study suggests that BK polyomavirus infection is not associated with urothelial malignancy in the immunocompetent setting unlike in the immunocompromised setting where it should always be investigated for.

Prognostic stratification of muscle invasive urothelial carcinomas using limited immunohistochemical panel of Gata3 and cytokeratins 5/6, 14 and 20.

BACKGROUND: Genomic studies have delineated distinct molecular subgroups of urothelial carcinomas whose prognostic impact extends beyond traditional stage and grade groupings. The 'basal' subgroup shows increased gene expression levels of KRT5, KRT6, and KRT14 and low expression levels of GATA binding protein 3, and is associated with an extremely poor outcome. Identification of this subset is necessary for improved patient management and research on targeted therapies. We aimed to assess the prognostic utility of immunohistochemistry (IHC) for basal markers: cytokeratin 5/6 (CK5/6) and 14 (CK14), and luminal markers: cytokeratin 20 (CK20) and Gata3 in muscle invasive urothelial carcinomas (MIBC). MATERIALS AND METHODS: Study was of retrospective design (2014-2017). All chemotherapy naïve patients of MIBC undergoing radical cystectomy were included. IHC was performed on formalin fixed paraffin-embedded whole tumor sections. RESULTS: Among 40 cases of MIBC included, 45% (18/40) were positive for one or both basal markers, 37.5% (15/40) were positive for one or both luminal markers, while 15% (6/40) were positive for both basal and luminal markers. One case did not express any of the four markers. MIBCs expressing only basal markers presented at an advanced stage with frequent squamous differentiation and showed a trend towards shorter overall survival. Gata3+ MIBCs showed the best outcome irrespective of expression of other markers, while CK14+/Gata3- MIBCs were associated with worst outcomes. Gata3-/CK14- MIBCs showed intermediate survival outcomes. CK5/6, CK20 and p53 expression did not significantly correlate with outcome. CONCLUSION: IHC for Gata-3 and CK14 stratified MIBC into distinct prognostic subsets.

ß-cyclodextrin encapsulated polyphenols as effective antioxidants.

Formation of dityrosine (DT) cross-linkages in proteins is one of the most widely used markers of oxidative stress. Ribonuclease A (RNase A) has 6 Tyr residues and shows a characteristic DT fluorescence peak upon oxidation in addition to major changes in its secondary structure. DT formation can be prevented by using polyphenols (GA, ECG, and EGCG) which are known to have strong antioxidant activity. However, it has been observed that ECG and EGCG initiate protein oligomerization due to protein-polyphenol cross-linkages. To prevent the formation of such cross-linkages we have used ß-cyclodextrin (ß-CD) to encapsulate the polyphenols and studied its antioxidant properties along with that of free polyphenols. The polyphenol/ß-cyclodextrin (ß-CD) inclusion complexes not only prevent DT formation but also reduce protein oligomerization. This may be attributed to the fact that the quinone forming rings of ECG and EGCG become encapsulated in the cavity of ß-CD and are no longer available for protein cross-linking.

Iron oxide labeling does not affect differentiation potential of human bone marrow mesenchymal stem cells exhibited by their differentiation into cardiac and neuronal cells.

Mesenchymal stem cells (MSCs) have shown promising outcomes in cardiac and neuronal diseases. Efficient and noninvasive tracking of MSCs is essential to harness their therapeutic potential. Iron oxide nanoparticles (IONPs) have emerged as effective means to label stem cells and visualize them using magnetic resonance imaging (MRI). It is known that IONPs do not affect viability and cell proliferation of stem cells. However, very few studies have demonstrated differentiation potential of iron oxide-labeled MSCs and their differentiation into specific lineages that can contribute to cellular therapies. The differentiation of IONP-labeled human bone marrow mesenchymal stem cells (hBM-MSCs) into cardiac and neuronal lineages has never been studied. In this study, we have shown that IONP-labeled hBM-MSCs retain their differentiation potential to cardiac and neuronal cell lineages. We also confirmed that labeling hBM-MSCs with IONP does not affect their characteristic properties such as viability, cellular proliferation rate, surface marker profiling, and trilineage differentiation capacity. This study shows that IONP can be efficiently tracked, and its labeling does not alter stemness and differentiation potential of hBM-MSCs. Thus, the labeled hBM-MSCs can be used in clinical therapies and regenerative medicine.

Genotype-Phenotype Correlations of Dystrophic Epidermolysis Bullosa in India: Experience from a Tertiary Care Centre.

Recent advances in the field of genomics have seen the successful implementation of whole exome sequencing as a rapid and efficient diagnostic strategy in several genodermatoses. The aim of this study was to explore the potential of molecular studies in dystrophic epidermolysis bullosa (DEB) in India. Whole exome sequencing was performed using genomic DNA from each case of epidermolysis bullosa, followed by massively parallel sequencing. Resulting reads were mapped to the human reference genome hg19. Sanger sequencing subsequently confirmed the potentially pathogenic mutations. Whole exome sequencing of 18 patients with DEB from 17 unrelated Indian families revealed 20 distinct sequence variants in the COL7A1 gene including 2 widely prevalent mutations. Dominant inheritance was seen in 7 patients, while 11 patients showed a highly variable recessive DEB. This preliminary study using exome sequencing is clearly encouraging and will serve as the basis for future large-scale molecular studies to actively identify and understand DEB in the Indian population.

Apigenin ameliorates streptozotocin-induced diabetic nephropathy in rats via MAPK-NF-κB-TNF-α and TGF-ß1-MAPK-fibronectin pathways.

Diabetic nephropathy (DN), a microvascular complication of diabetes, has emerged as an important health problem worldwide. There is strong evidence to suggest that oxidative stress, inflammation, and fibrosis play a pivotal role in the progression of DN. Apigenin has been shown to possess antioxidant, anti-inflammatory, antiapoptotic, antifibrotic, as well as antidiabetic properties. Hence, we evaluated whether apigenin halts the development and progression of DN in streptozotocin (STZ)-induced diabetic rats. Male albino Wistar rats were divided into control, diabetic control, and apigenin treatment groups (5-20 mg/kg po, respectively), apigenin per se (20 mg/kg po), and ramipril treatment group (2 mg/kg po). A single injection of STZ (55 mg/kg ip) was administered to all of the groups except control and per se groups to induce type 1 diabetes mellitus. Rats with fasting blood glucose >250 mg/dl were included in the study and randomized to different groups. Thereafter, the protocol was continued for 8 mo in all of the groups. Apigenin (20 mg/kg) treatment attenuated renal dysfunction, oxidative stress, and fibrosis (decreased transforming growth factor-ß1, fibronectin, and type IV collagen) in the diabetic rats. It also significantly prevented MAPK activation, which inhibited inflammation (reduced TNF-α, IL-6, and NF-κB expression) and apoptosis (increased expression of Bcl-2 and decreased Bax and caspase-3). Furthermore, histopathological examination demonstrated reduced inflammation, collagen deposition, and glomerulosclerosis in the renal tissue. In addition, all of these changes were comparable with those produced by ramipril. Hence, apigenin ameliorated renal damage due to DN by suppressing oxidative stress and fibrosis and by inhibiting MAPK pathway.

Mycophenolate mofetil is inferior to tacrolimus in sustaining remission in children with idiopathic steroid-resistant nephrotic syndrome.

Studies of nephrotic syndrome show that substitution of calcineurin inhibitors by mycophenolate mofetil (MMF) enables sustained remission and corticosteroid sparing and avoids therapy associated adverse effects. However, controlled studies in patients with steroid resistance are lacking. Here we examined the effect of switching from therapy with tacrolimus to MMF on disease course in an open-label, one-to-one randomized, controlled trial on children (one to 18 years old), recently diagnosed with steroid-resistant nephrotic syndrome, at a referral center in India. Following six months of therapy with tacrolimus, patients with complete or partial remission were randomly assigned such that 29 received MMF while 31 received tacrolimus along with tapering prednisolone on alternate days for 12 months. On intention-to-treat analyses, the proportion of patients with a favorable outcome (sustained remission, infrequent relapses) at one year was significantly lower (44.8%) in the MMF group than in the tacrolimus group (90.3%). The incidence of relapses was significantly higher for patients treated with MMF than tacrolimus (mean difference: 1.05 relapses per person-year). While there was no difference in the proportion of patients with sustained remission, the risk of recurrence of steroid resistance was significantly higher for patients receiving MMF compared to tacrolimus (mean difference: 20.7%). Compared to tacrolimus, patients receiving MMF had a significantly (71%) lower likelihood of a favorable outcome and significantly increased risk of treatment failure (frequent relapses, steroid resistance). Thus, replacing tacrolimus with MMF after six months of tacrolimus therapy for steroid-resistant nephrotic syndrome in children is associated with significant risk of frequent relapses or recurrence of resistance. These findings have implications for guiding the duration of therapy with tacrolimus for steroid-resistant nephrotic syndrome.

BK polyomavirus infection after renal transplantation: Surveillance in a resource-challenged setting.

BACKGROUND: There is a paucity of data available about BK polyomavirus (BKPyV) infection after renal transplantation (RTX) in resource-limited countries with a predominantly living-donor, ABO-compatible RTX program. We aimed to assess BKPyV infection in such patients in a public hospital in India. METHODS: We prospectively evaluated plasma BKPyV replication in 62 patients at 1, 3, 6, 9, and 12 months after RTX. Sustained significant BK viremia (SSBKV) was defined as significant viremia (≥10 000 copies/mL) detected ≥2 times, and BKPyV-associated nephropathy (BKVAN) as histologic changes of BKVAN with BK viremia with/without graft dysfunction. RESULTS: All patients underwent RTX without requiring desensitization. Incidence of BK viremia was: 17.7%, 41.9%, 16.1%, 25.8%, and 17.7% at 1, 3, 6, 9, and 12 months, respectively. Of 62 patients, 64.5% had BKPyV viremia during the study, 32.2% had significant viremia, all except one detected in the first 6 months. Nine (14.5%) patients had SSBKV. There was no biopsy-proven BKVAN. At the end of 1 year, mean serum creatinine was higher and graft dysfunction was significantly more common in patients with SSBKV compared to those without SSBKV. CONCLUSION: Transient BK viremia is common in low/intermediate immunologic risk RTX recipients in India, with a peak occurring at 3-6 months. Most clear their viremia by 12 months. Graft dysfunction seems to be more frequent in patients with SSBKV, although BKVAN is uncommon on biopsy in these patients.

Diagnosis of Inherited Epidermolysis Bullosa in Resource-Limited Settings: Immunohistochemistry Revisited.

BACKGROUND: Immunofluorescence (IFM) antigen mapping is the most commonly used technique to diagnose and differentiate epidermolysis bullosa (EB). In India, IFM is limited to few research laboratories and is not readily available, making the diagnosis largely clinical and often inaccurate. Ob jective of the Study: To examine the diagnostic usefulness of immunohistochemistry (IHC) as compared to IFM in resource-limited settings. METHODS: Forty-four consecutive EB patients were included in this study. IHC and IFM were performed on 7-µm frozen tissue sections using standard laboratory protocols with a limited panel of antibodies. The kappa coefficient of agreement was calculated with genetic analysis as the gold standard. RESULTS: IFM and IHC accurately identified the subtype of EB in 80.9% (p < 0.001) of the cases, when a clear blister cavity was evident on biopsy. The sensitivities and specificities of IHC and IFM for diagnosing EB simplex, junctional EB, and dystrophic EB were 100, 100, and 60% and 82.4, 100, and 100%, respectively. IHC was equally effective (p < 0.001) in establishing the type of EB as IFM. CONCLUSIONS: IHC staining and its interpretation were simple and comparable to IFM. IHC had an advantage of showing subtle changes in the epidermal architecture that could not be appreciated on IFM and hence can be considered useful in resource-limited settings.

Dense Deposit Disease Mimicking a Renal Small Vessel Vasculitis.

Dense deposit disease is caused by fluid-phase dysregulation of the alternative complement pathway and frequently deviates from the classic membranoproliferative pattern of injury on light microscopy. Other patterns of injury described for dense deposit disease include mesangioproliferative, acute proliferative/exudative, and crescentic GN. Regardless of the histologic pattern, C3 glomerulopathy, which includes dense deposit disease and C3 GN, is defined by immunofluorescence intensity of C3c two or more orders of magnitude greater than any other immune reactant (on a 0-3 scale). Ultrastructural appearances distinguish dense deposit disease and C3 GN. Focal and segmental necrotizing glomerular lesions with crescents, mimicking a small vessel vasculitis such as ANCA-associated GN, are a very rare manifestation of dense deposit disease. We describe our experience with this unusual histologic presentation and distinct clinical course of dense deposit disease, discuss the pitfalls in diagnosis, examine differential diagnoses, and review the relevant literature.

Glypican-3 mRNA expression level in Wilms tumor: correlation with histological type, stage, and outcome.

PURPOSE: To correlate expression of Glypican-3 in Wilms tumor with histopathology, stage, and outcome. METHODS: Glypican-3 mRNA expression by real-time PCR on tumor and normal germline samples from 75 fresh nephrectomies for Wilms tumor with fold change after normalization against GAPDH was compared. Survival analysis for event-free and overall survival (EFS, OS) with 2-year follow-up for Glypican-3 overexpression (>1.5 times) and clinicopathological parameters was performed. RESULTS: Glypican-3 was overexpressed in 37/75 (49.3%). It was overexpressed in 77% (10/13) cases with blastema predominance or anaplastic histology, as compared to 44% of other histologies (27/62) (p = 0.03). OS was 73 and 93%, respectively (p = 0.016), for those with and without GPC-3 overexpression. EFS was not significantly different with Glypican-3 overexpression (p = 0.11). All 5 deaths among blastema predominant tumors and 4/5 deaths among triphasic tumors had overexpressed Glypican-3. Most deaths in Stage IV, Stage III, and Stage I + II (5/7, 3/3, 1/1) had GPC-3 overexpression. On multivariate analysis, only histology and stage were found to have independent prognostic value. CONCLUSION: Glypican-3 overexpression in Wilms tumor correlates with poor OS on univariate analysis. However, only histology and stage have independent prognostic value. Glypican-3 levels may help to stratify intermediate outcome histology (triphasic) and Stage III Wilms tumors.