Polycyclic Aromatic Hydrocarbon-DNA Adducts in Gulf of Mexico Sperm Whale Skin Biopsies Collected in 2012.

The northern Gulf of Mexico has a long history of polycyclic aromatic hydrocarbon (PAH) contamination from anthropogenic activities, natural oil seepages, and the 2010 Deepwater Horizon explosion and oil spill. The continental shelf of the same area is a known breeding ground for sperm whales (Physeter macrocephalus). To evaluate PAH-DNA damage, a biomarker for potential cancer risk, we compared skin biopsies collected from Gulf of Mexico sperm whales in 2012 with skin biopsies collected from sperm whales in areas of the Pacific Ocean in 1999-2001. All samples were obtained by crossbow and comprised both epidermis and subcutaneous blubber. To evaluate exposure, 7 carcinogenic PAHs were analyzed in lipids extracted from Pacific Ocean sperm whale blubber, pooled by sex, and location. To evaluate PAH-DNA damage, portions of all tissue samples were formalin-fixed, paraffin-embedded, sectioned, and examined for PAH-DNA adducts by immunohistochemistry (IHC) using an antiserum elicited against benzo[a]pyrene-modified DNA, which crossreacts with several high molecular weight carcinogenic PAHs bound to DNA. The IHC showed widespread epidermal nuclear localization of PAH-DNA adducts in the Gulf of Mexico whales (n = 15) but not in the Pacific Ocean whales (n = 4). A standard semiquantitative scoring system revealed significantly higher PAH-DNA adducts in the Gulf of Mexico whales compared to the whales from the Pacific Ocean study (p = .0002).

We're All on This Spaceship Earth.

Description The photo features the geodesic sphere at Epcot, Disney World in Orlando, FL. Inside the dome, there was an iconic ride called "Spaceship Earth", which has since been shut down for refurbishment. This photo was taken November 2019, approximately 6 months before it was shut down. Much like how the ride emphasized the progress that human civilization has made in the last several hundred years and hopes to make in years to come, the current pandemic has shown us how far we have come in the medicine and other STEM fields. We hope only to do better and be better for everyone on our little Spaceship Earth.

Intestinal polycyclic aromatic hydrocarbon-DNA adducts in a population of beluga whales with high levels of gastrointestinal cancers.

Carcinogenic polycyclic aromatic hydrocarbons (PAHs) were disposed directly into the Saguenay River of the St. Lawrence Estuary (SLE) by local aluminum smelters (Quebec, Canada) for 50 years (1926-1976). PAHs in the river sediments are likely etiologically related to gastrointestinal epithelial cancers observed in 7% of 156 mature (>19-year old) adult beluga found dead along the shorelines. Because DNA adduct formation provides a critical link between exposure and cancer induction, and because PAH-DNA adducts are chemically stable, we hypothesized that SLE beluga intestine would contain PAH-DNA adducts. Using an antiserum specific for DNA modified with several carcinogenic PAHs, we stained sections of paraffin-embedded intestine from 51 SLE beluga (0-63 years), 4 Cook Inlet (CI) Alaska beluga (0-26 years), and 20 beluga (0-46 years) living in Arctic areas (Eastern Beaufort Sea, Eastern Chukchi Sea, Point Lay Alaska) and aquaria, all with low PAH contamination. Stained sections showed nuclear light-to-dark pink color indicating the presence of PAH-DNA adducts concentrated in intestinal crypt epithelial lining cells. Scoring of whole tissue sections revealed higher values for the 51 SLE beluga, compared with the 20 Arctic and aquarium beluga (P = 0.003). The H-scoring system, applied to coded individual photomicrographs, confirmed that SLE beluga and CI beluga had levels of intestinal PAH-DNA adducts significantly higher than Arctic and aquarium beluga (P = 0.003 and 0.02, respectively). Furthermore, high levels of intestinal PAH-DNA adducts in four SLE beluga with gastrointestinal cancers, considered as a group, support a link of causality between PAH exposure and intestinal cancer in SLE beluga. Environ. Mol. Mutagen. 60:29-41, 2019. Published 2018. This article is a U.S. Government work and is in the public domain in the USA.

Endophthalmitis Associated With Intravitreal Injections of Anti-VEGF Agents at a Tertiary Referral Center: In-House and Referred Cases.

BACKGROUND AND OBJECTIVE: To report the incidence rates, causative organisms, and visual acuity (VA) outcomes in patients with endophthalmitis associated with intravitreal injection of anti-vascular endothelial growth factor inhibitors. PATIENTS AND METHODS: Retrospective case series between 2005 and 2017. RESULTS: The study included 39 eyes of 39 patients, including 27 (69%) referred and 12 (31%) institutional patients. The use of topical antibiotics after an injection was gradually phased out at the authors' institution, where the preinjection rate of all clinically suspected endophthalmitis was 0.013% (24 of 183,898). The most common isolates were coagulase-negative Staphylococcus and Streptococcus. A VA of 5/200 or better was achieved in 21 of 39 eyes (54%) overall and in two of 15 eyes (13%) infected with Streptococcus. CONCLUSIONS: The rate of post-intravitreal injection endophthalmitis is low. Outcomes were generally poor, and the worst were associated with Streptococcus. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:313-319.].

Clinical features, antimicrobial susceptibilities, and treatment outcomes of patients with culture positive endophthalmitis after penetrating keratoplasty.

PURPOSE: To report the clinical features organisms and treatment outcomes in patients with endophthalmitis after penetrating keratoplasty (PK). METHODS: Retrospective noncomparative case series. RESULTS: Eleven eyes of 11 patients with culture positive endophthalmitis after PK were included. The time to diagnosis of endophthalmitis from last PK was less than 1 week in 3/11 (27%), between 1 and 4 weeks in 3/11 (27%), and greater than one month in 5/11 (46%) (range 2-924 days). The distribution of isolates included gram positive (GP) 9/11 (82%), gram negative (GN) 1/11 (9%), and fungal 1/11 (9%) species, respectively. Of GP bacteria tested, 9/9 (100%) were sensitive to Vancomycin. Of fungal isolates tested, none (0/1) were sensitive to Amphoteracin, Fluconazole, and/or Voriconazole. Among patients with rim culture data available, 1/7 (14%) donor rims were culture positive for Candida glabrata and 6/7 (86%) were culture negative. Patients were treated with primary tap and inject in 10/11 (91%) and primary vitrectomy in 1/11 (9%). VA of ≥5/200 was present in 2/11 (18%) at time of endophthalmitis diagnosis, and was recorded in 6/11 (55%) at last follow-up. CONCLUSIONS AND IMPORTANCE: Patients with endophthalmitis after PK presented at variable time points after surgery. Gram positive organisms were the most common isolate. VA outcomes after treatment were generally poor.

Clinical Features, Antibiotic Susceptibilities, and Treatment Outcomes of Endophthalmitis Caused by Staphylococcus epidermidis.

PURPOSE: To report the clinical features, antibiotic susceptibilities, and visual acuity outcomes with endophthalmitis caused by methicillin-sensitive Staphylococcus epidermidis and methicillin-resistant S. epidermidis. DESIGN: Retrospective case series. PARTICIPANTS: All patients seeking treatment at a tertiary referral center between 2006 and 2016 with endophthalmitis caused by S. epidermidis. METHODS: All records were reviewed for patients with a clinical diagnosis of endophthalmitis and positive vitreous culture results for S. epidermidis. Data were compared with the prior series at the same institution. MAIN OUTCOME MEASURES: Clinical settings, antibiotic susceptibilities, and visual acuity. RESULTS: Among 96 eyes of 96 patients, the most common postprocedural clinical settings were cataract surgery (47/96 [49%]), intravitreal injection (21/96 [22%]), trauma (8/96 [8%]), glaucoma surgery (7/96 [7%]), and penetrating keratoplasty (5/96 [5%]). The initial treatment included intravitreal vancomycin and ceftazidime in 89 of 96 eyes (93%) and intravitreal vancomycin and amikacin in 7 of 96 eyes (7%). A vitreous tap and injection with antibiotics was performed as the initial treatment in 83 of 96 eyes (86%) and pars plana vitrectomy was performed in 13 of 96 eyes (14%). All isolates were sensitive to vancomycin in both decades. In the most recent series, visual acuity at last follow-up was 5/200 or better in 68 of 96 eyes (71%) compared with 71 of 86 eyes (83%) in the prior study. In the current study, susceptibility to methicillin and moxifloxacin was present in 45 of 96 eyes (47%) and 29 of 85 eyes (34%), respectively, compared with 34 of 86 eyes (40%) and 27 of 39 eyes (69%) in the prior study. Final visual acuity was not significantly different between those eyes that were methicillin or fluoroquinolone sensitive and those that were resistant. CONCLUSIONS: In the current and prior series, all S. epidermidis isolates were sensitive to vancomycin. Visual acuity outcomes were not dependent on methicillin or fluoroquinolone sensitivity.

Endophthalmitis After Clear Corneal Cataract Surgery: Outcomes Over Two Decades.

PURPOSE: To report the clinical features, causative organisms, and visual acuity (VA) outcomes associated with acute-onset endophthalmitis after clear corneal cataract surgery over the past 2 decades. DESIGN: Retrospective case series. METHODS: Clinical and microbiology records were reviewed for 63 eyes of 63 patients who presented to a tertiary referral center between 2006 and 2015 with culture-positive endophthalmitis occurring within 6 weeks of clear corneal cataract surgery. RESULTS: The mean time between surgery and diagnosis of endophthalmitis was 8 days (median 6 days). The initial treatment included intravitreal vancomycin and ceftazidime in 59 of 63 (94%) eyes and intravitreal vancomycin and amikacin in 4 of 63 (6%) eyes. Intravitreal dexamethasone was used in 50 of 63 (79%) eyes. A vitreous tap and injection with antibiotics was performed as the initial treatment in 57 of 63 (90%) eyes and pars plana vitrectomy in 6 of 63 (10%) eyes. Coagulase-negative Staphylococcus was isolated in 39 of 63 (62%) eyes, Staphylococcus aureus in 7 of 63 (11%) eyes, and Streptococcus species in 7 of 63 (11%) eyes. A VA of ≥20/40 was achieved in 24 of 63 (38%) eyes. None of the gram-positive isolates were vancomycin resistant. Twenty-four of 49 isolates (49%) were sensitive to cephalothin, cefazolin, and cefuroxime. Sensitivity to fluoroquinolones included 22 of 52 (42%) to levofloxacin, 20 of 54 (37%) to ciprofloxacin, 16 of 47 (34%) to moxifloxacin, and 3 of 13 (23%) to gatifloxacin. CONCLUSION: Causative organisms and visual outcomes are similar to those reported in the prior decade. In the current study, a number of isolates were resistant to cephalosporins and fluoroquinolones.

Mesenteric neovascularization with distraction-induced intestinal growth: enterogenesis.

BACKGROUND: Distraction-induced enterogenesis, whereby the intestine lengthens with application of linear forces, is an emerging area which may provide a unique treatment for short bowel syndrome. With an increase in overall tissue mass, there is an increase in oxygen and nutrient demand. We hypothesized that a neovascularization within the mesentery is necessary to support the growing small bowel. METHODS: A curvilinear hydraulic device was used to induce growth within the small bowel of Yorkshire pigs, and the intestine was harvested after 14 days. High-resolution gross pictures were recorded of the mesentery at implantation and at harvest, and CT imaging of the bowel and mesentery was performed at harvest after dye injection. RESULTS: After 2 weeks of distraction, an average of 72.5 % (8.7 cm) bowel lengthening was achieved. Gross images of the mesentery between major vessels showed a blossoming of the microvasculature and this was confirmed by CT imaging with 3D reconstruction. Mesenteric sample taken from the distracted segment had a fourfold increase in the volume of microvasculature versus controls. CONCLUSION: Enterogenesis results not only in increased bowel length, but also significant increase in the mesenteric microvascularity. Presumably, this sustains the lengthened segment after application of longitudinal forces.