Biocompatible Cobalt Oxide Nanoparticles for X-ray Fluorescence Microscopy.

The synthesis of water-soluble nanoparticles is a well-developed field for ferrite-based nanoparticles with the majority consisting of iron oxide or mixed metal iron oxide nanoparticles. However, the synthesis of non-agglomerated non-ferrite metal/metal oxide NPs is not as well established. The synthesis and characterization of uniform 20 nm, biologically compatible cobalt oxide (CoO) nanoparticles (NPs) is described. These nanoparticles have two principle components: 1) a CoO core of suitable size to contain enough cobalt atoms to be visualized by X-ray fluorescence microscopy (XFM) and 2) a robust coating that inhibits NP aggregation as well as renders them water-soluble and biocompatible (i.e. stealth coatings). Stable cobalt oxide NPs are obtained with octadecyl amine coatings as reported by Bhattacharjee. Two strategies for solubilizing these NPs in water were investigated with varying degrees of success. Exchanging the octadecyl amine coating for a nitrodopamine anchored PEG coating yielded the desired water-soluble NPs but in very low yield. Alternately, leaving the octadecyl amine coating on the NP and interdigitating this with a maleic anhydride-vinyl copolymer with different hydrophobic sidechains followed by opening the maleic anhydride ring with amine substituted PEG polymers (the water solubilizing component), yielded the desired water soluble NPS were obtained in good yield. Characterization data for the nanoparticles and the components of the coatings required for bioorthogonal reactions to ligate them with biotargeting agents are also described.

Reevaluating the Spatial Scale of Residential Segregation: Racial Change Within and Between Neighborhoods.

This study evaluates the extent to which metropolitan racial segregation occurs between neighborhoods-from tract to tract-and within neighborhoods-from block to block-and is framed theoretically by Putnam's (2007) "hunkering down" hypothesis. Analyses are based on complete-count block, tract, and metropolitan data from the last four U.S. decennial censuses. We document recent patterns of block-to-block segregation between Whites and racial and ethnic minorities (Blacks, Asians, and Hispanics) and between different minority pairs. For example, roughly 40% of all metro Black-White segregation is due to segregation from block to block within neighborhoods. Among Asians, the between-neighborhood component of metropolitan segregation has increased over time but was largely compensated by declines in the within-neighborhood (or block) component. Metropolitan fixed-effects models show that trends and racial and ethnic differences in segregation-overall and within and between neighborhoods-are broadly observed across metro areas but are most evident in the largest, oldest, and most highly segregated metro areas. The results are robust to alternative estimates that adjust for differential privacy, metropolitan reclassification, and neighborhood boundary changes. Analyses of neighborhood change in Atlanta, Georgia, further reinforce the generality of our multiscale approach.

Rocky Mountain Spotted Fever Associated With Cardiac Arrhythmias.

Rickettsial infection, known as Rocky Mountain spotted fever, is a challenging diagnosis as early clinical manifestations are difficult to distinguish from viral illnesses. Symptoms at presentation depend on the organs involved, ranging from a skin rash as evidence of vascular damage to prerenal azotemia, respiratory failure, hepatic injury, or encephalitis. We report an unusual case of an otherwise healthy 83-year-old female whose serologies tested positive for Rickettsia rickettsii, which led to cardiac dysrhythmia, i.e., the new onset of atrial fibrillation associated with conversion pauses. The patient was treated with antibiotics and ultimately underwent permanent pacemaker placement with resolution. This case highlights cardiac dysrhythmia as a late and severe manifestation in patients diagnosed with rickettsial illness.

Vision Deficit Due to Pituitary Apoplexy.

Pituitary apoplexy means "sudden death" of the pituitary gland, usually caused by hemorrhage or infarction and often occurring in a pre-existing pituitary adenoma. In many cases, pituitary apoplexy is a medical and surgical emergency. Fast, efficient diagnosis and treatment are important in many cases. This case exemplifies an ideal lab workup and referral process to turn out best outcomes and prevent medical complications in our patient.

Pancreatic Dysfunction Masquerading as an Insulinoma.

Insulinoma is a rare neuroendocrine tumor that overproduces insulin, resulting in hypoglycemic symptoms. Elevated C-peptide levels in the absence of sulfonylurea use indicate insulinoma. Treatment is usually glucose administration and if the tumor size is large, surgery may be warranted. We present a case of a young man who had a one-year continuing episode of hypoglycemic symptoms that resolve after consuming high-glucose solids and liquids. Although symptoms pointed toward insulinoma, the 72-hour fasting test failed to show insulinoma. This case shows how following the algorithm accurately will prevent an inaccurate diagnosis.

African League Against Rheumatism (AFLAR) preliminary recommendations on the management of rheumatic diseases during the COVID-19 pandemic.

OBJECTIVES: To develop recommendations for the management of rheumatic and musculoskeletal diseases (RMDs) during the COVID-19 pandemic. METHOD: A task force comprising of 25 rheumatologists from the 5 regions of the continent was formed and operated through a hub-and-spoke model with a central working committee (CWC) and 4 subgroups. The subgroups championed separate scopes of the clinical questions and formulated preliminary statements of recommendations which were processed centrally in the CWC. The CWC and each subgroup met by several virtual meetings, and two rounds of voting were conducted on the drafted statements of recommendations. Votes were online-delivered and recommendations were pruned down according to predefined criteria. Each statement was rated between 1 and 9 with 1-3, 4-6 and 7-9 representing disagreement, uncertainty and agreement, respectively. The levels of agreement on the statements were stratified as low, moderate or high according to the spread of votes. A statement was retired if it had a mean vote below 7 or a 'low' level of agreement. RESULTS: A total of 126 initial statements of recommendations were drafted, and these were reduced to 22 after the two rounds of voting. CONCLUSIONS: The preliminary statements of recommendations will serve to guide the clinical practice of rheumatology across Africa amidst the changing practices and uncertainties in the current era of COVID-19. It is recognized that further updates to the recommendations will be needed as more evidence emerges. Key Points • AFLAR has developed preliminary recommendations for the management of RMDs in the face of the COVID-19 pandemic. • COVID-19 is an unprecedented experience which has brought new concerns regarding the use of some disease-modifying anti-rheumatic drugs (DMARDs), and these recommendations seek to provide guidelines to the African rheumatologists. • Hydroxychloroquine shortage has become rampart across Africa as the drug is being used as prophylaxis against COVID-19 and this may necessitate a review of treatment plan for some patients with RMDs. • Breastfeeding should continue for as long as possible if a woman is positive for SARS-CoV-2 as there is currently no evidence that the infection can be transmitted through breast milk.

Salvageability of renal function following renal revascularisation in children with Takayasu's arteritis-induced renal artery stenosis.

BACKGROUND: Renal artery revascularisation procedures are usually carried out on children with renal artery stenosis from varied causes, including Takayasu's arteritis. Reports on the outcome of such procedures in children usually refer to the improvement in blood pressure, with only minimal mention of effects on renal function. OBJECTIVE: Salvageability of renal function in children who underwent renal revascularisation for Takayasu's arteritis-induced renal artery stenosis (TARAS) was the focus of this study. METHODS: We undertook a retrospective analysis of children aged ≤16 years with angiographically confirmed TARAS who underwent renal artery revascularisation procedures between 1990 and 2010. Outcomes of renal function were studied over a period of 2 years and were defined as: (i) improvement: >20% increase in estimated glomerular filtration rate (e-GFR) from presurgery value; (ii) stabilisation: e-GFR within 20% of presurgery value; and (iii) failure: >20% deterioration in e-GFR from presurgery value. The GFR was estimated using the Schwartz formula. RESULTS: Twenty children (9 males and 11 females, age range 2 - 14 years) had 27 renal artery revascularisation procedures. Thirteen of the patients (65.0%) had bilateral renal artery stenosis. The baseline mean e-GFR was 88.6 (standard deviation (SD) 25.4) mL/min/1.73 m2 and the mean duration of follow-up was 28.80 (SD 25.62) months. All the patients had stable or improved renal function until the 2-year follow-up, when the proportion decreased to 92.3% (12/13), as failure was recorded in one child. Bilateral revascularisation was found to be significantly associated with improvement in renal function in the early postoperative period (p=0.04). CONCLUSION: Renal artery revascularisation procedures are successful in salvaging renal function in children with TARAS.

HIV-associated juvenile systemic sclerosis: a case report.

INTRODUCTION: Autoimmune connective tissue diseases occur in HIV-infected persons though with a lower frequency than in the general population. However, since the advent of highly active antiretroviral therapy (HAART), the spectrum of autoimmune diseases reported in HIV-infected patients has increased. OBJECTIVE: To describe the occurrence and management of systemic sclerosis in a HIV-infected child. METHODS: A case report of HIV-associated systemic sclerosis and a review of the literature on previously published cases. RESULTS: A nine-year-old girl presented with HIV-associated systemic sclerosis complicated with interstitial lung disease and oesophageal dysmotility. She was treated with intravenous cyclophosphamide with good response on her skin scores and modest improvement in lung function parameters. She manifested no deterioration in her clinical status. However, she developed mild lymphopaenia following the treatment with cyclophosphamide. CONCLUSION: We have described the rare occurrence of HIV infection and systemic sclerosis in a nine-year-old girl. She received cyclophosphamide for management of the systemic manifestations of SSc and did not manifest any major adverse events except mild lymphopaenia. Thus, though cyclophosphamide appeared safe in the management of HIV-associated systemic sclerosis, close monitoring of lymphocyte and CD4 counts should be done in such patients.