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The UMB Digital Archive is a service of the Health Sciences and Human Services Library (HS/HSL) that collects, preserves, and distributes the academic works of the University of Maryland, Baltimore. It is a place that digitally captures the historical record of the campus.
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Medical management of primary hyperparathyroidism in pregnancy: A case report and brief literature reviewThere is no established standard of care for the medical management of primary hyperparathyroidism in pregnancy for those patients who are not surgical candidates. We present a case of primary hyperpar-athyroidism in the third trimester that was managed with cinacalcet and a literature review on the various modalities for the medical management of primary hyperparathyroidism in pregnancy. The primary aim of this case report is to document a case of hyperparathyroidism in pregnancy that was managed medically and to perform a brief systematic review of the literature available on the medical management of primary hyperparathyroidism in pregnancy. The secondary aim is to contribute to the literature available on the use of cinacalcet in pregnancy. A 37-year-old woman with untreated primary hyperpar-athyroidism presented at 32 weeks of gestation with hypercalcemia that was not amenable to surgical intervention. We treated her with in-creasing doses of cinacalcet with improvement in her serum calcium until developing pre-eclampsia which prompted emergent cesarean delivery of the infant. The neonate developed respiratory distress after delivery but did not develop hypocalcemia after birth. The neonate became transiently hypercalcemic in the setting of calcium gluconate infusions given to prevent hypocalcemia. The patient underwent surgical removal of a parathyroid adenoma and required calcium sup-plementation for 1 month afterwards. Hypercalcemic crisis during pregnancy is associated with significant maternal and fetal morbidity. There is limited information regarding the medical management of primary hyperparathyroidism due to the lack of high-powered studies and prospective studies owing to the relative rarity of the condition. No serious adverse maternal events were reported for either bisphos-phonate or cinacalcet use. Adverse neonatal events include transient hypocalcemia of the infant with cinacalcet use and possibly low birth weight, infantile hypocalcemia, and shortened gestational periods with bisphosphonate use. Copyright The authors.
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Dental sealant empowered by 1,3,5-Tri acryloyl hexahydro-1,3,5-triazine and α-tricalcium phosphate for anti-caries applicationQuaternary ammonium compounds and calcium phosphates have been incorporated into dental materials to enhance their biointeractivity and preventive effects. This study aimed at evaluating the physical and chemical properties and effects against Streptococcus mutans of a dental sealant containing 1,3,5-tri acryloyl hexahydro-1,3,5-triazine (TAT) and ?-tricalcium phosphate (ff-TCP). A methacrylate-based dental sealant was initially formulated. ?-TCP and TAT (G?-TCPTAT) were added to the experimental sealant at 2 wt.% each. One group was formulated without ?-TCP and TAT and used as control (GCTRL). All tested resins were analyzed for polymerization kinetics and degree of conversion (DC %), Knoop hardness (KHN), softening in solvent (DKHN%), ultimate tensile strength (UTS), the contact angle with water or with ?-bromonaphthalene, surface free energy (SFE) and antibacterial activity against Streptococcus mutans in biofilm and in planktonic cells. The polymerization kinetic was different between groups, but without statistical differences in the DC % (p < 0.05). KHN and DKHN% did not change between groups (p > 0.05), but Gff-TCPTAT presented greater UTS compared to GCTRL (p < 0.05). No differences were found for contact angle (p > 0.05) or SFE (p > 0.05). Gff-TCPTAT showed greater antibacterial activity in comparison to GCTRL (p < 0.05). The formulation of dental sealants containing TAT and ff-TCP can be characterized by improved mechanical and antibacterial properties. Copyright 2020 by the authors.
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Harnessing data science to advance radiation oncologyRadiation oncology, a major treatment modality in the care of patients with malignant disease, is a technology- and computer-intensive medical specialty. As such, it should lend itself ideally to data science methods, where computer science, statistics, and clinical knowledge are combined to advance state-of-the-art care. Nevertheless, data science methods in radiation oncology research are still in their infancy and successful applications leading to improved patient care remain scarce. Here, we discuss data interoperability issues within and across organizational boundaries that hamper the introduction of big data and data science techniques in radiation oncology. At the semantic level, creating common underlying models and codification of the data, including the use of data elements with standardized definitions, an ontology, remains a work in progress. Methodological issues in data science and in the use of large population-based health data registries are identified. We show that data science methods and big data cannot replace randomized clinical trials in comparative effectiveness research by reviewing a series of instances where the outcomes of big data analyses and randomized trials are at odds. We also discuss the modern wave of machine learning and artificial intelligence as represented by deep learning and convolutional neural networks. Finally, we identify promising research avenues and remain optimistic that the data sources in radiation oncology can be linked to yield important insights in the near future. We argue that data science will be a valuable complement to, but not a replacement of, the traditional hypothesis-driven translational research chain and the randomized clinical trials that form the backbone of evidence-based medicine. Copyright 2020 The Authors.
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Escherichia coli ST131 clones harbouring AggR and AAF/V fimbriae causing bacteremia in Mozambican children: Emergence of new variant of fimH27 subcloneMultidrug-resistant Escherichia coli ST131 fimH30 responsible for extra-intestinal pathogenic (ExPEC) infections is globally distributed. However, the occurrence of a subclone fimH27 of ST131 harboring both ExPEC and enteroaggregative E. coli (EAEC) related genes and belonging to commonly reported O25:H4 and other serotypes causing bacteremia in African children remain unknown. We characterized 325 E. coli isolates causing bacteremia in Mozambican children between 2001 and 2014 by conventional multiplex polymerase chain reaction and whole genome sequencing. Incidence rate of EAEC bacteremia was calculated among cases from the demographic surveillance study area. Approximately 17.5% (57/325) of isolates were EAEC, yielding an incidence rate of 45.3 episodes/105 children-years-at-risk among infants; and 44 of isolates were sequenced. 72.7% (32/44) of sequenced strains contained simultaneously genes associated with ExPEC (iutA, fyuA and traT); 88.6% (39/44) harbored the aggregative adherence fimbriae type V variant (AAF/V). Sequence type ST-131 accounted for 84.1% (37/44), predominantly belonging to serotype O25:H4 (59% of the 37); 95.6% (35/44) harbored fimH27. Approximately 15% (6/41) of the children died, and five of the six yielded ST131 strains (83.3%) mostly (60%; 3/5) due to serotypes other than O25:H4. We report the emergence of a new subclone of ST-131 E. coli strains belonging to O25:H4 and other serotypes harboring both ExPEC and EAEC virulence genes, including agg5A, associated with poor outcome in bacteremic Mozambican children, suggesting the need for prompt recognition for appropriate management.
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Mechanosensing of Mechanical Confinement by Mesenchymal-Like CellsMesenchymal stem cells (MSCs) and tumor cells have the unique capability to migrate out of their native environment and either home or metastasize, respectively, through extremely heterogeneous environments to a distant location. Once there, they can either aid in tissue regrowth or impart an immunomodulatory effect in the case of MSCs, or form secondary tumors in the case of tumor cells. During these journeys, cells experience physically confining forces that impinge on the cell body and the nucleus, ultimately causing a multitude of cellular changes. Most drastically, confining individual MSCs within hydrogels or confining monolayers of MSCs within agarose wells can sway MSC lineage commitment, while applying a confining compressive stress to metastatic tumor cells can increase their invasiveness. In this review, we seek to understand the signaling cascades that occur as cells sense confining forces and how that translates to behavioral changes, including elongated and multinucleated cell morphologies, novel migrational mechanisms, and altered gene expression, leading to a unique MSC secretome that could hold great promise for anti-inflammatory treatments. Through comparison of these altered behaviors, we aim to discern how MSCs alter their lineage selection, while tumor cells may become more aggressive and invasive. Synthesizing this information can be useful for employing MSCs for therapeutic approaches through systemic injections or tissue engineered grafts, and developing improved strategies for metastatic cancer therapies. Copyright � 2020 Doolin, Moriarty and Stroka.