Bioinspired Metal-Organic Framework Catalysts for Selective Methane Oxidation to Methanol.

Particulate methane monooxygenase (pMMO) is an enzyme that oxidizes methane to methanol with high activity and selectivity. Limited success has been achieved in incorporating biologically relevant ligands for the formation of such active site in a synthetic system. Here, we report the design and synthesis of metal-organic framework (MOF) catalysts inspired by pMMO for selective methane oxidation to methanol. By judicious selection of a framework with appropriate topology and chemical functionality, MOF-808 was used to postsynthetically install ligands bearing imidazole units for subsequent metalation with Cu(I) in the presence of dioxygen. The catalysts show high selectivity for methane oxidation to methanol under isothermal conditions at 150 °C. Combined spectroscopies and density functional theory calculations suggest bis(µ-oxo) dicopper species as probable active site of the catalysts.

Cutaneous Malignant Melanoma Presenting as an Isolated Splenic Metastasis: An Update.

Although the spleen is a highly vascularized organ, metastatic deposits from non-hematolymphoid solid malignancies are rare. This is reasoned to the inherent resistance of the splenic parenchyma to harbor metastases. The splenic capsule, lack of afferent lymphatics, contractile properties of the spleen, and the angular and gyroid course of the splenic artery form several barriers against the metastatic spread of malignant tumors. Moreover, the immune cells in the white and red pulps of the spleen have strong defensive ability against the tumor cells. Metastasis from solid tumors to the spleen often occurs only during widespread distant spread. Malignant melanoma is a rare but fatal malignancy. Isolated splenic metastasis from malignant melanoma is exceptionally rare. Studies that addressed the splenic metastasis from cutaneous malignant melanoma are scarce. This minireview was performed to address this subject. Here we present an overview of the clinicopathologic features of isolated splenic metastatic melanoma. The diagnostic biochemical markers in melanoma are also discussed.

Primary Localized Amyloidosis of the Intestine: A Pathologist Viewpoint.

BACKGROUND: Localized amyloidosis of the intestine is a rare entity, which can clinically masquerade several conditions such as colitis, polyps, and malignant tumors. This study aims to evaluate the clinicopathological features of this entity. METHODS: To evaluate the clinicopathological features of this entity, a comprehensive search of the literature (1960 to 2019) was done using the following keywords: "amyloidosis" and "small intestine" or "duodenum" or "ileum" or "jejunum" or "colon". We identified 756 studies about gastrointestinal amyloidosis. Data were examined for 27 studies about localized intestinal amyloidosis. The clinicopathological features were described. RESULTS: The age at presentation ranged from 29 to 88 years. The male to female ratio was 3:1. The jejunum and sigmoid colon were the most commonly involved sites. Abdominal pain and intestinal obstruction (small intestine), or rectal bleeding (sigmoid region) were the most common clinical presentations. Colonoscopic findings included wall thickening, mucosal ulcerations (small intestine), and tumor-like masses (colon). CONCLUSIONS: The clinical presentations of localized intestinal amyloidosis depend on the site of the deposition of the amyloid. In most cases, amyloid deposits consisted of light chain protein.

Family structure and children's unmet health-care needs.

This study assessed children's unmet health-care needs within different family types (two-parent biological/adoptive, two-parent stepfamily, and single-mother family type) using data from the 2011/2012 National Survey of Children's Health. Findings indicate that 10.4% of children in single-mother family types had unmet health-care needs compared to 8.7% of children from a two-parent stepfamily and 5.3% for those from two-parent biological/adoptive families. Further analyses revealed racial/ethnic disparities with Black children from two parent-biological/adoptive families being 1.54 (95% confidence interval 1.13, 2.05) times more likely to have unmet health-care needs, while Hispanic children were less likely to have unmet health-care needs relative to their white counterparts. Children from lower income two-parent families had a higher likelihood of unmet health-care needs. The noncontinuous insurance coverage was a risk factor for increasing unmet health-care needs across all three different family types. These findings show major differences in unmet health-care needs among children living in different family structure types. It is recommended that interventions for increasing access to care need to be tailored differently across various family types in order to achieve continuous and sufficient health-care services for our children.