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Starry stonewort (Nitellopsis obtusa) (Desvaux in Loiseleur) J. Groves is an invasive macro alga that can take over entire water columns and outcompete native species. Previous research has quantified seasonal life history and phenology but there is no research quantifying carbohydrate allocation. The current study utilized samples harvested from Lake Koronis, Minnesota, USA from 2020 and 2021 to quantify starch allocation patterns in N. obtusa. Starch was quantified using the amylase/amyloglucosidase method. Starch data were compared to light transmittance (%), pH and water temperature (°C) via mixed procedures models in SAS. Seasonal average low and high points of starch storage were observed to be June (3.3%) and April (9.9%) for thalli biomass then June (41.7%) and November (54.6%) for bulbils. In regard to allocation patterns, above ground thalli reallocates carbohydrate stores to the below ground rhizoids in May. Carbohydrates are then transported to bulbils from July through September as rhizoid starch decreases and the bulbil starch increases. Ultimately, the carbohydrates are converted to starch and stored in bulbils (21.0–73.7%). In its invaded range, bulbils are important for energy store, vegetative reproduction and spread, as well as temporal distribution. These bulbils spread easily, spread rapidly, can store a lot of energy (73% starch), and are a major concern for the invasion of N. obtusa. Water temperature and light availability were shown to negatively influence starch content of thalli. These findings suggest that in the invaded range, N. obtusa is capable of accumulating large amounts of starch later into the growing season. The energy reserves may give N. obtusa a competitive advantage over native species by allowing a longer growing season resulting in the production of more vegetative propagules and greater longevity in the environments it invades. [ABSTRACT FROM AUTHOR]

Point intercept surveys were conducted on Swan Lake and Middle Lake, Minnesota to quantitatively assess aquatic macrophyte distribution and abundance. A sediment particle size analysis was conducted to determine if sediment particle size influenced sago pondweed (Stuckenia pectinata (L.) Böraer) and wild celery ( Vallisneria americana Michx.) distribution. Swan Lake had more macrophyte species than Middle Lake. Sago pondweed distribution was different between 2001 and 2002 in Middle Lake. Wild celery was only found in Swan Lake and its distribution was also different between sample years. The presence of sago pondweed was positively related to percentage of clay in Swan Lake sediments. The presence of wild celery was negatively related to the percentage of clay in the sediment. No relationship was found between sediment particle size and sago pondweed growing in Middle Lake. [ABSTRACT FROM AUTHOR]

In the summer of 1910, William James Mayo, M.D., delivered the commencement address at Rush Medical College in Chicago. In his speech, he uttered words that have become the cornerstone of Mayo Clinic's model of care: "The best interest of the patient is the only interest to be considered, and in order that the sick may have the benefit of advancing knowledge, a union of forces is necessary." In this article, we reflect on issues raised by Mayo's speech that strike at the very heart of our professional identity and ask two questions: Is medicine's foremost concern the best interest of the patient? And has medicine really united over the last century in the service of patients?

Objective: To investigate circadian rhythm (CR) of urinary creatinine and 8-hydroxy-2-deoxyguanosine (8-OHdG) in patients with Multiple Sclerosis (MS) and to present concentrations of this DNA damage marker, 5 years prior to mastectomy, in one MS study subject, and 2 years prior to biopsy confirmed a carcinoma (CA) of the prostate in one non-MS subject., Materials and Methods: Eleven subjects with MS (6 women 36-52 years of age and 5 men 51-68 years) volunteered for this study, carried out at Edward Hines Jr., Medical Center. Subjects were offered a general hospital diet (2400 cal in total/24h) at 16:30h, 07:30h and 13:00h. The dark (sleep) phase of the light-dark cycle extended from 22:30h to 06:30h with brief awakening for sampling at 01:00h, and 04:00h. Urine samples were collected for consecutive 3h spans beginning at 16:00-19:00h and were analyzed for creatinine and 8-OHdG. Twelve men (including 3 with type 2 diabetes) provided 21 profiles according to the same protocol used for comparison. In addition, 10 healthy women provided 24h urine samples. Statistical analysis of data was performed using the Single-Cosinor and Population-Mean Cosinor., Results: A CR was detected for creatinine in healthy men (p < 0.001) but not for MS patients. Urinary creatinine concentrations were lower in MS women than in healthy women (p = 0.015) and were lower in MS women than in men healthy or with MS (p < 0.001): Women; MS 655 +/- 76; H 1381 +/- 316; Men, MS 1830 +/- 285; H 1532 +/- 265 mg/24h vol. A CR was evident in 8-OHdG in MS (p = 0.007) and in non-MS subjects (p < 0.001) with highest values occurring at about 16:45h. The average concentrations of 8-OHdG in MS patients were similar to those in healthy subjects: Women, MS 589 +/- 125; H 794 +/- 318; Men, MS 504 +/- 156; H 591 +/- 134 picomoles/kg bw/24h vol. The 8-OHdG concentrations of a MS patient, later diagnosed with breast cancer, were found to exceed the upper 95% prediction limit in health. An increased 8-OHdG level was also noted in a non-MS subject who 2 years later received a biopsy-confirmed diagnosis of prostate CA., Conclusions: Despite the small number of subjects in this study, a statistically significant CR was documented for 8-OHdG in urine of subjects with MS. Interestingly, the increased concentrations of DNA damage marker, the 8-OHdG, 5 years prior to mastectomy and the 2 years prior to affirmative diagnosis of prostate CA, could be the most significant clinical observations of this study. Follow-up studies of a larger population of subjects would, thus, be required to ascertain the predictive validity of such challenging observation.