From the Cover: Gut bacteria facilitate adaptation to crop rotation in the western corn rootworm

Insects are constantly adapting to human-driven landscape changes; however, the roles of their gut microbiota in these processes remain largely unknown. The western corn rootworm (WCR, Diabrotica virgifera virgifera LeConte) (Coleoptera: Chrysomelidae) is a major corn pest that has been controlled via annual rotation between corn (Zea mays) and nonhost soybean (Glycine max) in the United States. This practice selected for a “rotation-resistant” variant (RR-WCR) with reduced ovipositional fidelity to cornfields. When in soybean fields, RR-WCRs also exhibit an elevated tolerance of antiherbivory defenses (i.e., cysteine protease inhibitors) expressed in soybean foliage. Here we show that gut bacterial microbiota is an important factor facilitating this corn specialist’s (WCR''s) physiological adaptation to brief soybean herbivory. Comparisons of gut microbiota between RR- and wild-type WCR (WT-WCR) revealed concomitant shifts in bacterial community structure with host adaptation to soybean diets. Antibiotic suppression of gut bacteria significantly reduced RR-WCR tolerance of soybean herbivory to the level of WT-WCR, whereas WT-WCR were unaffected. Our findings demonstrate that gut bacteria help to facilitate rapid adaptation of insects in managed ecosystems.     

Problems Confronting the Food and Drug Administration in Drug Evaluation

Distribution of subcutaneously injected cadmium 109 (¹⁰⁹Cd) was studied in mature rats over a period of 14 days. Tthe isotope was primarily deposited in the kidneys, liver, and pancreas. Within four hours after injection, cadmium appeared in the wall and in the contents of the small intestine. In the colon and in its contents, the concentration of the isotope increased gradually over a period of 24 hours. Cadmium content in the intestinal tract decreased progressively between 30 and 336 hours after injection. The stomach wall concentrated and retained ¹⁰⁹Cd, and only traces of the isotope appeared in the contents of the stomach. From the blood plasma, cadmium disappeared rapidly, whereas the blood cells showed an increase in cadmium concentration between 24 and 336 hours after injection.     

High Prevalence of Subclinical Atherosclerosis by Carotid Ultrasound among Mexican Americans: Discordance with 10‐Year Risk Assessment using the Framingham Risk Score

Background: Framingham risk scores (FRS) were validated in a mostly Caucasian population. Evaluation of subclinical atherosclerosis by carotid ultrasound may improve ascertainment of risk in nonwhite populations. This study aimed to evaluate carotid intima‐media thickness (cIMT) and carotid plaquing among Mexican Americans, and to correlate these markers with coronary risk factors and the FRS. Methods/Results: Participants (n = 141) were drawn from the Cameron County Hispanic Cohort. Carotid artery ultrasound was performed and cIMT measured. Carotid plaque was defined as areas of thickening >50% of the thickness of the surrounding walls. Mean age was 53.1 ± 11.7 years (73.8% female). Most were overweight or obese (88.7%) and more than half (53.2%) had the metabolic syndrome. One third (34.8%) had abnormal carotid ultrasound findings (either cIMT ≥75th percentile for gender and age or presence of plaque). Among those with abnormal carotid ultrasound, the majority were classified as being at low 10‐year risk for cardiovascular events. Carotid ultrasound reclassified nearly a third of the cohort as being at high risk. This discordance between 10‐year FRS and carotid ultrasound was noted whether risk was assessed for hard coronary events or global risk. Concordance between FRS and carotid ultrasound findings was best when long‐term (30‐year) risk was assessed and no subject with an abnormal carotid ultrasound was categorized as low risk by the 30‐year FRS algorithm. Conclusions: Integration of carotid ultrasound findings to coronary risk assessments and use of longer term prediction models may provide better risk assessment in this minority population, with earlier initiation of appropriate therapies.     

Analysis of a large single‐center experience with robot‐assisted pyeloplasty

Objectives: To report a single‐center experience with robot‐assisted pyeloplasty. Methods: Medical records of 100 consecutive robot‐assisted pyeloplasty cases carried out between May 2004 and August 2010 were retrospectively reviewed, and major perioperative parameters were recorded. Patients underwent functional (renal scan) and/or anatomical (ultrasound or computerized tomoghraphy) imaging at 6 months. Results: The mean patient age was 39.8 years. A total of 12 patients underwent prior attempts at repair. Ureteral stents were placed in all patients except one, and closed‐suction drains were placed in 59 patients. There were two intraoperative complications and two postoperative complications requiring surgical intervention. One patient with a complex prior surgical history developed a urine leak that was managed with prolonged drainage. A total of 42 patients were discharged on postoperative day 1, and 44 were discharged on postoperative day 2. Mean length of follow up was 22.8 months. The operative success rate was 96%. Conclusions: The majority of patients undergoing robot‐assisted pyeloplasty can expect a short hospitalization with minimal morbidity. The operative success rate is high, even in patients with prior attempts at repair. Complication rates including urine leaks are quite low, and routine placement of a closed‐suction drain is likely to be unnecessary.     

Degenerative scoliosis and stenosis—Surgical management

Adult degenerative scoliosis affects the growing elderly population and is an expanding challenge for spine surgeons. The etiology and natural history of this disease are imperfectly understood; however, it is accepted that degenerative spinal curvature is likely to progress. Severe deformity, particularly in the sagittal plane, is poorly tolerated. Treatment is complicated in this population where comorbid or mimicking diseases are the norm. Where appropriate, surgery is undertaken only after a thorough assessment of each patient’s spinal geometry. Guidelines aid in selecting among or combining surgical procedures. Increased potential for correction generally involves increased risk. Complications are common after surgery for adult degenerative scoliosis and their management should be anticipated.     

Gut microbiota as a source of a surrogate antigen that triggers autoimmunity in an immune privileged site

Recent discoveries on the role of commensal microbiota have significantly changed our understanding of human physiology. The host-microbiota interplay is now an important aspect to take into account to understand immune responses and immunological diseases. Autoimmune uveitis is a sight-threatening disease that arises without a known infectious etiology. It is unknown where and how autoreactive T cells become primed to trigger disease in the eye, which is an immune privileged site. We recently reported data supporting the notion that retina-specific T cells receive a signal in the gut from commensal microbiota-derived cross-reactive antigen(s) and trigger autoimmune uveitis in the R161H mouse model. Here we discuss our published findings, as well as our recent attempts to identify the responsible microbe(s) by using different antibiotic treatments, 16S rDNA sequencing and homology searches for candidate antigenic mimic(s) of the retinal antigen.