Analysis of COVID-19 Case Demographics and Disease Outcomes in Gary, Indiana

BACKGROUND

The COVID-19 pandemic further exposed the prevalence of existing health disparities in Black communities in the U.S. The current study evaluates COVID-19 data collected in Gary, Indiana, from June 2020 to June 2021. We hypothesized that the number of COVID-19 cases, hospitalizations, and deaths were influenced by race and income.

METHODS

In collaboration with the Gary Health Department (GHD), we analyzed demographic data on COVID-19-positive cases.

RESULTS

Compared to Gary's non-Black population, age- and population-adjusted rates of hospitalizations and deaths in the Black population were 3-fold (p < 0.0001) and 2-fold (p < 0.05) higher, respectively. This is despite a higher infection rate (p < 0.0001) in the non-Black population. The median household income of a zip code was negatively correlated with COVID-19 hospitalizations (R2 = 0.6345, p = 0.03), but did not correlate with infections and deaths.

CONCLUSIONS

The current study demonstrates clear health disparities of income and race in the context of COVID-19-related infections and outcomes in the city of Gary. Indiana University School of Medicine Northwest and GHD officials can collaborate to utilize these data for the reallocation of resources and health education efforts in Gary's highly populated, low-income, and predominantly Black neighborhoods. It should also prompt further investigation into national health resource allocation.

Morphological and functional characteristics of three-dimensional engineered bone-ligament-bone constructs following implantation

The incidence of ligament injury has recently been estimated at 400,000/year. The preferred treatment is reconstruction using an allograft, but outcomes are limited by donor availability, biomechanical incompatibility, and immune rejection. The creation of an engineered ligament in vitro solely from patient bone marrow stromal cells (has the potential to greatly enhance outcomes in knee reconstructions. Our laboratory has developed a scaffoldless method to engineer three-dimensional (3D) ligament and bone constructs from rat bone marrow stem cells in vitro. Coculture of these two engineered constructs results in a 3D bone-ligament-bone (BLB) construct with viable entheses, which was successfully used for medial collateral ligament (MCL) replacement in a rat model. 1 month and 2 month implantations were applied to the engineered BLBs. Implantation of 3D BLBs in a MCL replacement application demonstrated that our in vitro engineered tissues grew and remodeled quickly in vivo to an advanced phenotype and partially restored function of the knee. The explanted 3D BLB ligament region stained positively for type I collagen and elastin and was well vascularized after 1 and 2 months in vivo. Tangent moduli of the ligament portion of the 3D BLB 1 month explants increased by a factor of 2.4 over in vitro controls, to a value equivalent to those observed in 14-day-old neonatal rat MCLs. The 3D BLB 1 month explants also exhibited a functionally graded response that closely matched native MCL inhomogeneity, indicating the constructs functionally adapted in vivo.

Protein kinase C and calcium/calmodulin-activated protein kinase II (CaMK II) suppress nicotinic acetylcholine receptor gene expression in mammalian muscle. A specific role for CaMK II in activity-dependent gene expression

Nicotinic acetylcholine receptor (nAChR) gene expression is regulated by both muscle activity and increased intracellular calcium. This regulation is an important developmental event that rids receptors from the extrajunctional region of the developing muscle fiber. In avian muscle, it has been proposed that muscle activity suppresses nAChR gene expression via calcium-activated protein kinase C (PKC)-dependent phosphorylation of the myogenic transcription factor, myogenin. Here, we examined the role that PKC and other kinases play in mediating calcium- and activity-dependent suppression of nAChR genes in rat primary myotubes. We found that although activated PKC could regulate nAChR promoter activity and transiently suppressed both nAChR and myogenin gene expression, it did not appear to be required for calcium- or activity-dependent control of nAChR gene expression in mammalian muscle. Neither depletion of PKC from myotubes nor specific pharmacological inhibition of PKC blocked the suppression of nAChR gene expression produced by calcium or muscle depolarization. In contrast, we provide evidence that calcium/calmodulin-activated protein kinase II participates in mediating the effects of muscle depolarization on nAChR and myogenin gene expression.

Distal urinary acidification from Homer Smith to the present

Since Smith's time, the essential role of collecting duct intercalated cells in controlling net acid excretion has been recognized. Rather than employing an H(+)-exchange mechanism, intercalated cells have V-ATPase on the plasma membrane and in plasmalemma-associated tubulovesicles, which functions in the bicarbonate reabsorption, regeneration, and bicarbonate secretion required for acid-base homeostasis. Several distinct mechanisms participate in regulating V-ATPase-driven H+ secretion in different cell types: (1) Renal epithelial cells have the capacity to express different structural forms of V-ATPase that have intrinsic differences in their enzymatic properties. 2) The kidney produces cytosolic regulatory proteins, capable of interacting directly with the V-ATPase, that may modify its activity. V-ATPases in different cell types may differ in the degree to which their activity is affected by regulatory factors, as a result of variations in V-ATPase structure. (3) In the alpha intercalated cell, the number of active V-ATPases on the luminal membrane is controlled in vivo by membrane vesicle-mediated traffic that may require unidentified mediators. In the beta intercalated cell, the number of active V-ATPases on the basolateral membrane may be controlled by regulated assembly and disassembly, responding directly to extracellular pH.