The Liver in Hemophagocytic Lymphohistiocytosis: Not an Innocent Bystander.

Hemophagocytic lymphohistiocytosis (HLH) is a rare multisystemic hyperinflammatory disease commonly associated with hepatic dysfunction. Liver injury is mediated by unchecked antigen presentation, hypercytokinemia, dysregulated cytotoxicity by natural killer and CD8 T cells, and disruption of intrinsic hepatic metabolic pathways. Over the past decade, there have been significant advances in diagnostics and expansion in therapeutic armamentarium for this disorder allowing for improved morbidity and mortality. This review discusses the clinical manifestations and pathogenesis of HLH hepatitis in both familial and secondary forms. It will review growing evidence that the intrinsic hepatic response to hypercytokinemia in HLH perpetuates disease progression and the novel therapeutic approaches for patients with HLH-hepatitis/liver failure.

Isolated Terminal Ileitis in Children.

Isolated terminal ileitis in adults is a well described entity that rarely progresses to Crohn disease (CD), and pediatric literature on this topic is very limited. We describe the prevalence, clinical, endoscopic, histologic, and radiological features, along with long-term outcome of isolated terminal ileitis in our institution. We reviewed charts of 956 children who underwent colonoscopy from 2013 to 2017. Thirty-three children had isolated histologically-defined terminal ileitis. Seventeen children were diagnosed with CD and 16 children had idiopathic terminal ileitis. Children with CD had higher prevalence of abnormal C-reactive protein levels, severe inflammation, and radiological evidence of bowel wall thickening compared with children with idiopathic ileitis. Children with idiopathic ileitis did not develop CD over a follow-up period of 83 months. In contrast to adults, CD is common in children with isolated terminal ileitis and those with idiopathic ileitis do well over long-term.

Hepatitis B and C in Children.

Hepatitis B and hepatitis C are a global burden and underscore the impact of preventable acute and chronic diseases on personal as well as population level health. Caring for pediatric patients with hepatitis B and C requires a deep understanding of the pathophysiology of viral processes. Insight into the epidemiology, transmission, and surveillance of these infections is critical to prevention and therapy. Extensive research in recent years has created a growing number of treatments, changing the landscape of the medical field's approach to the viral hepatitis pandemic.

Atomic Clock Measurements of Quantum Scattering Phase Shifts Spanning Feshbach Resonances at Ultralow Fields.

We use an atomic fountain clock to measure quantum scattering phase shifts precisely through a series of narrow, low-field Feshbach resonances at average collision energies below 1 µK. Our low spread in collision energy yields phase variations of order ±π/2 for target atoms in several F, m_{F} states. We compare them to a theoretical model and establish the accuracy of the measurements and the theoretical uncertainties from the fitted potential. We find overall excellent agreement, with small statistically significant differences that remain unexplained.

Accelerated follicle depletion in vitro and in vivo in Sprague-Dawley rats using the combination of 4-vinylcyclohexene diepoxide and triptolide.

Rodent pests cause major damage to the world's agricultural crops and food stores. Rodenticides used since World War II did not lead to sustained reduction of rodent populations, and so fertility control is becoming attractive because rats reproduce with great efficiency. Chemical acceleration of ovarian failure via oral dosing also would improve management of rat pest populations. The chemical 4-vinylcyclohexene diepoxide (VCD) is orally efficacious, causing depletion of nonregenerating primordial ovarian follicles of Sprague-Dawley rats. However, to cause rapid reduction in pups in the first breeding cycle after dosing, all stages of ovarian follicle development must be targeted. To achieve this goal, the Chinese herb triptolide was tested because it can precipitate apoptosis and deplete growing follicles. The impact of triptolide was tested in cultured postnatal day 4 Sprague-Dawley rat pup ovaries. Triptolide at 5 nM caused 100% primordial, primary, and secondary follicle depletion after 8 days of culture, compared to 38% follicle depletion caused by VCD at 30 microM. Next, a palatable rat bait was developed, containing 1% VCD with increasing concentrations of triptolide at 25, 50, and 100 microg/kg body weight. Rats ate an average 3-6% of their body weight/day over 15 feeding days. Two days after the end of baiting, rats were euthanized to conduct necropsies and collect ovaries to count all follicular stages and corpora lutea. At 50 microg triptolide/kg body weight, there was significant reduction of all follicular stages; primordial follicles were 50% lower, secondary follicles were 64% lower, antral follicles were 80% lower, and there were no corpora lutea. These results suggest that combining VCD and triptolide in an oral bait leads to significantly compromised rat ovarian function and reduced ovulations, and is likely to reduce pup production.

Direct observation of resonant scattering phase shifts and their energy dependence.

We scan the collision energy of two clouds of cesium atoms between 12 and 50 µK in an atomic fountain clock. By directly detecting the difference of s-wave scattering phase shifts, we observe a rapid variation of a scattering phase shift through a series of Feshbach resonances. At the energies we use, resonances that overlap at threshold become resolved. Our statistical phase uncertainty of 8 mrad can be improved in future precision measurements of Feshbach resonances to accurately determine the Cs-Cs interactions, which may provide stringent limits on the time variation of fundamental constants.