Ancient Maya iconography primarily depicted elite individuals in idealized states of being and rationalized their power and authority through ideological concepts and otherworld beings. This study aims to reexamine previous assumptions made concerning the Quadripartite Badge. This motif is examined based on iconographic associations and contexts, as well as temporal and spatial distributions. The dataset was created from currently identified examples of the Quadripartite Badge, although only a select group is extensively examined. The spread of this motif is demonstrated through time and its spatial dispersals are noted for their political consequences. Indicating the liminal status of its user, the Badge is frequently placed in scenes of transformation, accompanying rites of passage. It is also established that as elite women became more prominent, women from Tikal and Calakmul circulated this iconography through marriage alliances, as seen in the number of newly ‘arrived’ women carrying the Badge. Other iconographic associations of the Badge revealed strong ties with the Maize God and the cyclical nature of agriculture. For the continuation of the maize cycle and renewal of universal forces, sacrifice was required; the completion of ritual sacrifice was demonstrated through the depiction of the Quadripartite Badge. This one expression of power simultaneously validated earthly and otherworldy authority, ensuring the continuation of the cosmos and the perpetuation of the sun and maize cycles

No description available.

This chapter focuses on the role of antioxidant vitamins in protecting the gastrointestinal (GI) tract from oxidative stress. A systems medicine approach is used since it alone is sufficiently comprehensive to capture the broad range of relevant complexities and interrelationships relevant to GI protection. Systems medicine utilizes and integrates the vast amount of information gained from genomics and metagenomics, as well as environmental factors, and applies this information to better patient care. A major goal of system medicine is to develop paradigms to treat or slow the progression of chronic diseases, that is, disease prevention. GI disorders are quintessential examples of chronic inflammation with its attendant oxidative stress. Genomics and metagenomics have provided great insight into the underlying molecular mechanisms for GI disorders and will eventually help define individualized diets to minimize chronic inflammation. While the role of antioxidant nutrients and micronutrients is promising, there is a need for large-scale well-designed clinical trials supported by studies using animal models.

No description available.

Long term consumption of a high fat diet (HFD) increases the risk of developing Metabolic Syndrome and type 2 diabetes. This led us to hypothesize that long term HFD consumption impairs immune tolerance to the intestinal bacteria. Our studies had two goals. First, we characterized the effect of long term HFD consumption on the systemic immune response by comparing C57BL6 mice fed a HFD and low fat diet (LFD). Plasma immunoglobulin G (IgG) against Escherichia coli (LF-82), E. coli (Nissle 1917), Bacteroides thetaiotaomicron and Lactobacillus acidophilus were measured by a lab-developed ELISA. Fasting blood glucose and inflammation were measured in LFD mice and HFD mice. To test whether our findings were clinically relevant, anti-bacterial IgG and TNF-α were measured in plasma samples from lean healthy individuals, obese non-diabetics and obese diabetics. Our second aim was to investigate the relationship between HFD consumption and intestinal immunity. The effect of HFD consumption on immune responses in the GI tract was assessed by measuring fecal IgA levels in HFD mice and LFD mice. HFD mice had higher plasma IgG against the LF82 strain of Escherichia coli as well as higher plasma TNF-α, neutrophil percentage and fasting blood glucose levels. Obese diabetics had higher plasma IgG against the LF82 strain of E. coli than lean healthy controls. Studies on the effect of HFD on intestinal immunity revealed that HFD mice had lower fecal IgA than LFD mice. Our findings are novel in that they show an association between long term HFD consumption, systemic inflammatory immune responses to pathogenic intestinal bacteria and insulin resistance. These studies also showed that HFD consumption may impair intestinal immunity.

在民初西南政局中，唐繼堯曾一度扮演主導的角色，並於他當權的歲月□，屢次出兵 川黔，意圖囊括西南半壁江山，隱然成為西南的盟主；但終因連年用兵，實力耗損， 伏下敗亡之機。唐氏一生環扣著整個西南的局勢，因此本文寫作之目的，即在於透過 對唐氏生平的探討，以尋求民初西南政局發展之脈絡。全文除緒論、結論外，共分五 章： 第一章「唐繼堯的崛起」：敘述唐氏的早年經歷，說明唐氏在鼎革之際，攀昇權力高 峰的過程。 第二章「護國時期」：記述雲南發動護國之役的始末，探究唐氏反袁的真正原因，並 對唐氏做一客觀之平議。 第三章「靖國時期」：探討雲南對外擴張的背景，西南各省衝突的因素，唐氏對護法 的態度，以及唐氏出亡之經緯。 第四章「『建國』時期」：說明唐氏二次回滇的經過，探討「建國」時期唐的政治主 張，最後則分析倒唐政變的前因後果。 第五章「建設雲南」：敘述唐氏建設雲南的動機、經過及成果。 通過以上各章節，不但探討了唐氏的人生歷程，也清楚說明了唐氏與西南政局的互動 關係。

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

The Melatonin, a close derivative of serotonin, is involved in physiological regulation of circadian rhythms. In the gastrointestinal (GI) system, melatonin exhibits endocrine, paracrine and autocrine actions and is implicated in the regulation of GI motility. Generally, melatonin actions oppose the stimulatory actions of serotonin on motility. However, it is not known whether melatonin can also act directly on GI smooth muscle cells. The aim of the present study was to determine the expression of melatonin receptors in smooth muscle and identify their signaling pathways. Muscle cells were isolated from rabbit distal stomach by enzymatic digestion, filtration and centrifugation and cultured in DMEM-10. Expression of melatonin receptors, MT1 and MT2, was determined by RT-PCR and Western blot. G protein activity was measured by melatonin-induced increase in Gα binding to [35S]GTPγS. Phosphoinositide (PI)-specific phospholipase C (PLC-) activity was measured by ion-exchange chromatography. Cytosolic Ca2+ was measured in fura-2 loaded cells and muscle contraction was measured by scanning micrometry. In cultured gastric smooth muscle cells MT1 was detected by RT-PCR and western blot. Melatonin activated Gαq, but not Gαs, Gαi1, Gαi2, or Gαi3. Consistent with activation of Gαq, melatonin stimulated PLC-β activity (PI hydrolysis), increased cytosolic Ca2+, and elicited muscle contraction. Stimulation of PLC-β activity was blocked by the expression of Gq minigene and contraction was blocked by the PLC-β inhibitor, U73122. We conclude that gastric smooth muscle cells express receptors for melatonin (MT1) coupled to Gq. The receptors mediate stimulation of PLC- activity and increase in cytosolic Ca2+, and elicit muscle contraction.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

The glycemic index (GI) of a pre-exercise meal has been shown to affect substrate oxidation during exercise and may influence exercise performance. Previous research in this area has focused on continuous, moderate intensity exercise. The purpose of this study was to examine the effects of low and high glycemic index (GI) pre-exercise meals on metabolism and performance during soccer-specific intermittent exercise. Thirteen trained male soccer players (22.3 ± 3.3 yrs) participated in four experimental trials in a repeated crossover design. Isocaloric low GI-high protein (lentils), high GI-high protein (potato + egg whites), or high GI-low protein (potato) meals were consumed two hours before a 90-minute treadmill soccer match simulation. A fasted control condition was also employed. Blood and expired gas samples were collected before and during exercise to assess markers of carbohydrate and fat metabolism. The distance covered on five 1-minute sprints (separated by 2.5 minutes of recovery) performed during the last 15 minutes of the match was used to assess performance. Serum insulin concentration at the start of exercise was higher in the high GI-low protein condition compared to all other conditions (p<0.001). During exercise, the rate of carbohydrate oxidation was significantly higher and the rate of fat oxidation was significantly lower in the high GI-low protein condition compared to control (p<0.05). The distance covered on sprints 1 and 2 was significantly greater in the low GI-high protein condition compared to control (p<0.05). The distance covered on sprint 2 was significantly greater in the high GI-high protein condition compared to control (p<0.05). There were no significant differences between conditions for sprints 3-5. Ratings of perceived exertion (RPE) throughout exercise were significantly lower in the low GI-high protein condition compared to both control and high GI-low protein conditions (p<0.05). It is concluded that low GI-high protein and high GI-high protein pre-exercise meals result in small improvements in initial repeated sprint performance compared to fasted control. Performance was not improved following a high GI-low protein pre-exercise meal compared to control, indicating that the increased carbohydrate oxidation and decreased fat oxidation in this condition may have negated any potential performance advantage of carbohydrate consumption. The lower RPE throughout exercise in low GI-high protein compared to control and high GI-low protein indicates a possible beneficial effect of consuming a low GI meal prior to soccer-specific intermittent exercise.