Primary T-cell Vitreoretinal Non-Hodgkin Lymphoma: A Case Report and Literature Review.

A 72-year-old Chinese male presented with unilateral left eye panuveitis, then diagnosed as bilateral T-cell primary vitreoretinal lymphoma (T-PVRL) through chorioretinal biopsy and immunohistochemistry. No CNS nor systemic involvement was found at diagnosis. Despite initiating intravenous and intrathecal chemotherapy and intravitreal methotrexate, the disease eventually spread to the fellow eye with subsequent recurrence and systemic metastasis. To our knowledge, no cases of T-PVRL treated in a silicone-filled eye were reported in the literature. T- PVRL is exceedingly rare, with most PVRL being the malignant B-cell variant. This case highlights the challenges encountered throughout the treatment course of this aggressive entity, including the administration of intravitreal methotrexate in a silicone oil-filled eye. The poor overall survival rate and grim prognosis of T-PVRL are highlighted. Therefore, we recommend prompt tissue biopsy and immediate initiation of systemic chemotherapy and intravitreal methotrexate.

Prostate MRI evolution in clinical practice: Audit of tumour detection and staging versus prostatectomy with staged introduction of multiparametric MRI and Prostate Imaging Reporting and Data System v2 reporting.

INTRODUCTION: We conducted a retrospective audit to compare dominant nodule detection and local staging before and after the introduction of functional sequences and PI-RADS v2 reporting to MRI prostate scans in routine private practice. METHODS: A retrospective audit was performed of 245 patients in four separate groups undergoing robotic prostatectomy for prostate cancer by a single urologist between 2009 and 2017. The initial 100 consecutive patients had T2 imaging only. The next 43 patients had T2 and DWI. 52 subsequent patients had T2, DWI and DCE sequences (mpMRI). A final 50 consecutive patients had mpMRI using PI-RADS v2 reporting. Preoperative MRI reports were compared with prostatectomy histopathology to determine the sensitivity of MRI in detecting dominant tumour nodule and T3 extension. RESULTS: The addition of DWI and DCE sequences improved sensitivity for detection of dominant tumour nodule, with a significant further increase using PI-RADS v2 reporting (38% for T2 vs. 62% for T2/DWI vs. 67% for mpMRI vs 91% for PI-RADS v2). The accuracy of detecting T3 disease was initially very low. The use of additional imaging techniques did not significantly influence this, but the use of a three category likelihood of extraprostatic extension in the PI-RADS v2 group had a significant increase in detection of T3 disease (sensitivity 27% vs. 23% vs. 38% vs 63%). CONCLUSION: This audit tracks the significant improvements in MRI detection of prostate cancer dominant tumour nodule and T3 extension in patients undergoing prostatectomy with changing techniques and reporting standards in routine clinical practice.

Pneumonitis: a serious adverse effect of PD-L1 inhibitors including pembrolizumab.

A 70-year-old man presented with breathlessness, cough and fever while receiving pembrolizumab for melanoma. A CT pulmonary angiogram demonstrated small bilateral upper lobe segmental pulmonary emboli with patchy ground-glass opacities and basal perilobular consolidation, in keeping with organising pneumonia. He was treated for community-acquired pneumonia and pulmonary emboli but rapidly deteriorated, with increasing hypoxia and dyspnoea. He was admitted to the intensive care unit for support with continuous positive airway pressure and high flow nasal oxygen. His clinical condition improved once he received high-dose intravenous methylprednisolone to treat pneumonitis. His treatment was continued with a weaning course of high-dose oral steroids, and he was discharged with a persistent oxygen requirement. The patient maintained a requirement for high doses of oral steroids and continued to deteriorate. He was referred to palliative care for symptom management and died a month following hospital discharge, as a result of pneumonitis due to pembrolizumab.

Lung Function, Inflammation, and Endothelin-1 in Congenital Heart Disease-Associated Pulmonary Arterial Hypertension.

BACKGROUND: Breathlessness is the most common symptom in people with pulmonary arterial hypertension and congenital heart disease (CHD-APAH), previously thought to be caused by worsening PAH, but perhaps also by inflammation and abnormalities of lung function. We studied lung function and airway inflammation in patients with CHD-APAH and compared the results with controls. METHODS AND RESULTS: Sixty people were recruited into the study: 20 CHD-APAH, 20 CHD controls, and 20 healthy controls. Spirometry, gas transfer, whole body plethysmography and lung clearance index, 6-minute walk distance, and medical research council dyspnea scoring were performed. Inflammatory markers and endothelin-1 levels were determined in blood and induced sputum. The CHD-APAH group had abnormal lung function with lung restriction, airway obstruction, and ventilation heterogeneity. Inverse correlations were shown for CHD-APAH between medical research council dyspnea score and percent predicted peak expiratory flow (r=-0.5383, P=0.0174), percent predicted forced expiratory flow rate at 50% of forced vital capacity (r=-0.5316, P=0.0192), as well as for percent predicted forced expiratory volume in 1 s (r=-0.6662, P=0.0018) and percent predicted forced vital capacity (r=-0.5536, P=0.0186). The CHD-APAH patients were more breathless with lower 6-minute walk distance (360 m versus 558 m versus 622 m, P=0.00001). Endothelin-1, interleukin (IL)-ß, IL-6, IL-8, tumor necrosis factor α, and vascular endothelial growth factor were significantly higher in CHD-APAH than controls. Serum endothelin-1 for CHD-APAH correlated with airflow obstruction with significant negative correlations with percent predicted forced expiratory flow rate at 75% of forced vital capacity (r=-0.5858, P=0.0135). CONCLUSIONS: Raised biomarkers for inflammation were found in CHD-APAH. Significant abnormalities in airway physiology may contribute to the dyspnea but are not driven by inflammation as assessed by circulating and sputum cytokines. A relationship between increased serum endothelin-1 and airway dysfunction may relate to its bronchoconstrictive properties.

Designing anti-Zika virus peptides derived from predicted human-Zika virus protein-protein interactions.

The production of anti-Zika virus (ZIKV) therapeutics has become increasingly important as the propagation of the devastating virus continues largely unchecked. Notably, a causal relationship between ZIKV infection and neurodevelopmental abnormalities has been widely reported, yet a specific mechanism underlying impaired neurological development has not been identified. Here, we report on the design of several synthetic competitive inhibitory peptides against key pathogenic ZIKV proteins through the prediction of protein-protein interactions (PPIs). Often, PPIs between host and viral proteins are crucial for infection and pathogenesis, making them attractive targets for therapeutics. Using two complementary sequence-based PPI prediction tools, we first produced a comprehensive map of predicted human-ZIKV PPIs (involving 209 human protein candidates). We then designed several peptides intended to disrupt the corresponding host-pathogen interactions thereby acting as anti-ZIKV therapeutics. The data generated in this study constitute a foundational resource to aid in the multi-disciplinary effort to combat ZIKV infection, including the design of additional synthetic proteins.

Endobronchial ultrasound-guided transbronchial needle aspiration.

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is an increasingly used technique by the interventional pulmonologist in lung cancer staging and diagnosis of both malignant and benign mediastinal lymphadenopathy amongst other applications. There are increasing data to support the use of EBUS-TBNA over mediastinoscopy as a first staging or diagnostic procedure in defined situations. In this review, the technique of EBUS-TBNA is briefly discussed with a more extended discussion around comparative studies of mediastinal staging techniques, with an emphasis on the recent ASTER trial as well as impending trials and diagnostic performance studies of EBUS-TBNA in sarcoidosis.

TLR regulation of SPSB1 controls inducible nitric oxide synthase induction.

The mammalian innate immune system has evolved to recognize foreign molecules derived from pathogens via the TLRs. TLR3 and TLR4 can signal via the TIR domain-containing adapter inducing IFN-ß (TRIF), which results in the transcription of a small array of genes, including IFN-ß. Inducible NO synthase (iNOS), which catalyzes the production of NO, is induced by a range of stimuli, including cytokines and microbes. NO is a potent source of reactive nitrogen species that play an important role in killing intracellular pathogens and forms a crucial component of host defense. We have recently identified iNOS as a target of the mammalian SPSB2 protein. The SOCS box is a peptide motif, which, in conjunction with elongins B and C, recruits cullin-5 and Rbx-2 to form an active E3 ubiquitin ligase complex. In this study, we show that SPSB1 is the only SPSB family member to be regulated by the same TLR pathways that induce iNOS expression and characterize the interaction between SPSB1 and iNOS. Through the use of SPSB1 transgenic mouse macrophages and short hairpin RNA knockdown of SPSB1, we show that SPSB1 controls both the induction of iNOS and the subsequent production of NO downstream of TLR3 and TLR4. Further, we demonstrate that regulation of iNOS by SPSB1 is dependent on the proteasome. These results suggest that SPSB1 acts through a negative-feedback loop that, together with SPSB2, controls the extent of iNOS induction and NO production.

The SPRY domain-containing SOCS box protein SPSB2 targets iNOS for proteasomal degradation.

Inducible nitric oxide (NO) synthase (iNOS; NOS2) produces NO and related reactive nitrogen species, which are critical effectors of the innate host response and are required for the intracellular killing of pathogens such as Mycobacterium tuberculosis and Leishmania major. We have identified SPRY domain-containing SOCS (suppressor of cytokine signaling) box protein 2 (SPSB2) as a novel negative regulator that recruits an E3 ubiquitin ligase complex to polyubiquitinate iNOS, resulting in its proteasomal degradation. SPSB2 interacts with the N-terminal region of iNOS via a binding interface on SPSB2 that has been mapped by nuclear magnetic resonance spectroscopy and mutational analyses. SPSB2-deficient macrophages showed prolonged iNOS expression, resulting in a corresponding increase in NO production and enhanced killing of L. major parasites. These results lay the foundation for the development of small molecule inhibitors that could disrupt the SPSB-iNOS interaction and thus prolong the intracellular lifetime of iNOS, which may be beneficial in chronic and persistent infections.

Solution conformation, backbone dynamics and lipid interactions of the intrinsically unstructured malaria surface protein MSP2.

Merozoite surface protein 2 (MSP2), one of the most abundant proteins on the surface of the merozoite stage of Plasmodium falciparum, is a potential component of a malaria vaccine, having shown some efficacy in a clinical trial in Papua New Guinea. MSP2 is a GPI-anchored protein consisting of conserved N- and C-terminal domains and a variable central region. Previous studies have shown that it is an intrinsically unstructured protein with a high propensity for fibril formation, in which the conserved N-terminal domain has a key role. Secondary structure predictions suggest that MSP2 contains long stretches of random coil with very little alpha-helix or beta-strand. Circular dichroism spectroscopy confirms this prediction under physiological conditions (pH 7.4) and in more acidic solutions (pH 6.2 and 3.4). Pulsed field gradient NMR diffusion measurements showed that MSP2 under physiological conditions has a large effective hydrodynamic radius consistent with an intrinsic pre-molten globule state, as defined by Uversky. This was supported by sedimentation velocity studies in the analytical ultracentrifuge. NMR resonance assignments have been obtained for FC27 MSP2, allowing the residual secondary structure and backbone dynamics to be defined. There is some motional restriction in the conserved C-terminal region in the vicinity of an intramolecular disulfide bond. Two other regions show motional restrictions, both of which display helical structure propensities. One of these helical regions is within the conserved N-terminal domain, which adopts essentially the same conformation in full-length MSP2 as in corresponding peptide fragments. We see no evidence of long-range interactions in the full-length protein. MSP2 associates with lipid micelles, but predominantly through the N-terminal region rather than the C terminus, which is GPI-anchored to the membrane in the parasite.

Predicting HIV coreceptor usage on the basis of genetic and clinical covariates.

BACKGROUND: We compared several statistical learning methods for the prediction of HIV coreceptor use from clonal HIV third hypervariable (V3) loop sequences, and evaluated and improved their effectiveness on clinical samples. METHODS: Support vector machines (SVM), artificial neural networks, position-specific scoring matrices (PSSM) and mixtures of localized rules were estimated and tested using 10x ten-fold cross-validation on a clonal dataset consisting of 1,100 matched clonal genotype-phenotype pairs from 332 patients. Different SVMs were also trained and tested on a clinically derived dataset, representing 920 patient samples from British Columbia, Canada. Methods were evaluated using receiver operating characteristic (ROC) curves. RESULTS: In the clonal analysis, the sensitivity of the 11/25 rule at 92.5% specificity was 59.5%. PSSMs and SVMs increased sensitivity to 71.9% and 76.4%, respectively, at the same specificity (P < < 0.05). In clinical samples, the sensitivity of the 11/25 rule and SVM decreased to 25.9% (specificity 93.9%) and 39.8% (specificity 93.5%), respectively. However, the integration of clinical data resulted in a further 2.4-fold increase in sensitivity over the 11/25 rule (63%). Univariate analyses identified 41 V3 mutations significantly associated with coreceptor usage. CONCLUSION: For all methods tested, a substantial sensitivity decrease is observed on clinical data, probably owing to the heterogeneity of the viral population in vivo. In response to these complications, we present an SVM-based approach that integrates sequence information with clinical and host data, resulting in improved performance and sensitivity compared with purely sequence-based approaches.

Current V3 genotyping algorithms are inadequate for predicting X4 co-receptor usage in clinical isolates.

OBJECTIVE: Integrating CCR5 antagonists into clinical practice would benefit from accurate assays of co-receptor usage (CCR5 versus CXCR4) with fast turnaround and low cost. DESIGN: Published HIV V3-loop based predictors of co-receptor usage were compared with actual phenotypic tropism results in a large cohort of antiretroviral naive individuals to determine accuracy on clinical samples and identify areas for improvement. METHODS: Aligned HIV envelope V3 loop sequences (n = 977), derived by bulk sequencing were analyzed by six methods: the 11/25 rule; a neural network (NN), two support vector machines, and two subtype-B position specific scoring matrices (PSSM). Co-receptor phenotype results (Trofile Co-receptor Phenotype Assay; Monogram Biosciences) were stratified by CXCR4 relative light unit (RLU) readout and CD4 cell count. RESULTS: Co-receptor phenotype was available for 920 clinical samples with V3 genotypes having fewer than seven amino acid mixtures (n = 769 R5; n = 151 X4-capable). Sensitivity and specificity for predicting X4 capacity were evaluated for the 11/25 rule (30% sensitivity/93% specificity), NN (44%/88%), PSSM(sinsi) (34%/96%), PSSM(x4r5) (24%/97%), SVMgenomiac (22%/90%) and SVMgeno2pheno (50%/89%). Quantitative increases in sensitivity could be obtained by optimizing the cut-off for methods with continuous output (PSSM methods), and/or integrating clinical data (CD4%). Sensitivity was directly proportional to strength of X4 signal in the phenotype assay (P < 0.05). CONCLUSIONS: Current default implementations of co-receptor prediction algorithms are inadequate for predicting HIV X4 co-receptor usage in clinical samples, particularly those X4 phenotypes with low CXCR4 RLU signals. Significant improvements can be made to genotypic predictors, including training on clinical samples, using additional data to improve predictions and optimizing cutoffs and increasing genotype sensitivity.