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Background: Phenotypic frailty syndrome identifies older adults at greater risk for adverse health outcomes. Despite the critical role of mitochondria in maintaining cellular function, including energy production, the associations between muscle mitochondrial energetics and frailty have not been widely explored in a large, well-phenotyped, older population. Methods: The Study of Muscle, Mobility and Aging (SOMMA) assessed muscle energetics in older adults (N = 879, mean age = 76.3 years, 59.2% women). 31Phosporous magnetic resonance spectroscopy measured maximal production of adenosine triphosphate (ATPmax) in vivo, while ex vivohigh-resolution respirometry of permeabilized muscle fibers from the vastus lateralis measured maximal oxygen consumption supported by fatty acids and complex I- and II-linked carbohydrates (e.g., Max OXPHOSCI+CII). Five frailty criteria, shrinking, weakness, exhaustion, slowness, and low activity, were used to classify participants as robust (0, N= 397), intermediate (1-2, N= 410), or frail (≥ 3, N= 66). We estimated the proportional odds ratio (POR) for greater frailty, adjusted for multiple potential confounders. Results: One-SD decrements of most respirometry measures (e.g., Max OXPHOSCI+CII, adjusted POR = 1.5, 95%CI [1.2,1.8], p= 0.0001) were significantly associated with greater frailty classification. The associations of ATPmaxwith frailty were weaker than those between Max OXPHOSCI+CIIand frailty. Muscle energetics was most strongly associated with slowness and low physical activity components. Conclusions: Our data suggest that deficits in muscle mitochondrial energetics may be a biological driver of frailty in older adults. On the other hand, we did observe differential relationships between measures of muscle mitochondrial energetics and the individual components of frailty.

The Everglades National Park (ENP) has one of the largest mangrove forests in the United States, yet due to lack of data and methods, there has been no multidecadal record of detailed changes in its mangrove forests, not to mention their response to periodic hurricanes. Here, based on remote sensing spectroscopy, multisensor cross calibration, spectral normalization, and pixel unmixing, we develop a stepwise method to map distributions and changes of the ENP mangrove forests and other major wetlands cover types (marshes and hardwood hammocks) over the last three decades. The time series of Landsat‐based results indicate statistically significant increasing trend from 1985 to 2017 in the total ENP mangrove coverage with a cumulative increase of 10.2%, which has increased in the inner coastline area but decreased in the outer coastline area. The mangrove coverage also decreased considerably in certain hurricane years (1992, 2005, and 2017), with the largest decrease of 644.9 km2(46.5% of the mean mangrove area in normal years) occurring in 1993 after Hurricane Andrew. Yet, these large mangrove die‐off areas gradually recovered to prehurricane levels 3–4 years after the passage of major hurricanes. Results also indicate that while the mangrove forests were always damaged by hurricanes, the extent of the damage depended on wind speed, direction, and distance from maximum wind. The findings here could serve as baseline information for future restoration efforts of the ENP ecosystem, and the study also provides a method extendable to other coastal wetland regions. Three decades of mangrove changes in the Everglades National Park are quantified from Landsat observationsBased on cross‐sensor calibration, spectral normalization and pixel unmixing, a method is developed and validated with high‐resolution mapMangrove coverage has decreased significantly after hurricanes, but recovered in subsequent years

Dysregulated CD4 T cell responses are causally linked to autoimmune and chronic inflammatory disorders, yet the cellular attributes responsible for maintaining the disease remain poorly understood. Herein, we identify a discrete population of effector CD4 T cells that is able to both sustain and confer intestinal inflammation. This subset of pathogenic CD4 T cells possesses a unique gene signature consistent with self-renewing T cells and hematopoietic progenitor cells, exhibits enhanced survival, and continually seeds the terminally differentiated IFNγ-producing cells in the inflamed intestine. Mechanistically, this population selectively expresses the glycosyltransferase ST6Gal-I, which is required for optimal expression of the stemness-associated molecule TCF1 by effector CD4 T cells. Our findings indicate that the chronicity of T cell–mediated inflammation is perpetuated by specific effector CD4 T cells with stem-like properties.

DNA within a cell is organized with unrestrained torsional tension, and each molecule is divided into multiple individual topological domains. Psoralen photobinding can be used as an assay for supercoiling and topological domain size in living cells. Psoralen photobinds to DNA at a rate nearly linearly proportional to superhelical density. Comparison of the rate of photobinding to supercoiled and relaxed DNA in cells provides a measure of superhelical density. For this,in vivosuperhelical tension is relaxed by the introduction of nicks by either ionizing radiation or photolysis of bromodeoxyuridine in the DNA. Since nicks are introduced in a random fashion, the distribution of nicks is described by a Poisson distribution. Thus, after nicking, the fraction of topological domains containing no nicks is described by the zero term of the Poisson distribution. From measurement of the number of nicks introduced in the DNA and the fraction of torsional tension remaining, an average topological domain size can be estimated. Using this logic, procedures were designed and described for measuring supercoiling and domain size at specific sites in eukaryotic genomes.

A patient with inflammatory bowel disease had massive lower gastrointestinal bleeding, at first thought to be from inflammatory bowel disease. Subsequently we recognized the bleeding as coming from a Meckel's diverticulum only by repeating the angiographic study within a few minutes after the initial angiogram was negative. This experience illustrates the intermittency of gastrointestinal bleeding from minute to minute. Moreover, a review of the literature suggests that a Meckel's diverticulum may more often be found in patients with Crohn's disease than in the general population, a possibility which deserves further study.

A 160 year record of skeletal δ13C and δ18O was examined in a specimen of the coral Solenastrea bournonigrowing in Florida Bay. Variations in the δ18O of the skeleton can be correlated to changes in salinity while changes in the δ13C reflect cycling of organic material within the Bay. Based on the correlation between salinity and skeletal δ18O, we have concluded that there has been no long term increase in salinity in this area of Florida Bay over the past 160 years. Using salinity correlations between the various basins obtained from instrumental data, we have been able to extend our interpretations to other parts of Florida Bay reaching similar conclusions. In contrast to current ideas which have focused on changes in Florida Bay water quality over the past 20-yr history of the Bay as causative in its decline, we have determined that changes in water quality in this basin were already set in motion between 1905 and 1912 by the construction of the Florida East Coast Railway from Miami to Key West. The construction of the railway resulted in the restriction of the exchange of water between the Florida reef tract and the Gulf of Mexico causing Florida Bay to become more eutrophic. Evidence of this process is observed in the sudden shift to relatively lower δ13C values coincident with railway construction. Natural events also appear to have influenced the water in the Bay. Between 1912 and 1948 frequent hurricanes had the effect of increasing exchange of water between the Bay and reef tract and removing large quantities of organic rich sediments. However, since 1948 the number of hurricanes affecting the area has decreased and the products of the oxidation of organic material have been increasingly retained within the basin promoting the initiation of eutrophic conditions.

Commonly used antimotility and antidiarrheal drugs were administered to six ileostomized subjects to determine whether their normal ileal excreta and that induced by prune juice could be altered. A total of 49 studies were performed, 21 with and 28 without prune juice. Bismuth subgallate was the only drug which significantly reduced the normal ileal excreta (P<0.05). Codeine sulfate decreased the ileal excreta in two of three subjects in either type of study. The third subject was a nonresponder to drugs. Deodorized tincture of opium (DTO) and diphenoxylate (Lomotil) were also effective in some subjects. Propantheline, tincture of belladonna, Sorboquel, and Kaopectate did not appear to decrease ileal excreta. Calcium carbonate, on the other hand, increased ileal excreta; fat excretion was also increased.

In 12 of 18 studies on human gastric secretion a fall in free acid occurred after chlorothiazide was administered. In 3 of the 12 patients the decrease was definite, i.e., 60–100 per cent of basal secretion, in 4 the results equivocal, and in 5 the fall was not significant. The decrease in free acid was transient, lasting for 1 hour.

A case of ulcerative colitis is reported in which restoration of intestinal continuity 27 yr. after an ileostomy led to flare-up of the disease. Ileostomy and colectomy were necessary to control the disease. This case seems to emphasize the opinion expressed already in 1932 that “ileostomy for ulcerative colitis should be permanent.”3

Present evidence would indicate that two or possibly more types of bilirubin, known historically as direct and indirect bilirubin, exist. The differences reside in the chemical nature of each bilirubin and not in the nature of the protein linkage. Direct bilirubin is a water-soluble compound probably in the form of a conjugated bilirubin-glucuronide11; because of its solubility, direct bilirubin is excreted in the urine. Both types of bilirubin are associated with serum albumin which probably acts simply as a vehicle for carrying the pigment. The van den Bergh test measures two types of bilirubin; at the pH at which the reaction is conducted each type is dissociated from its protein molecule. The role of alcohol in the van den Bergh is unknown and is not that of separating bilirubin from protein.

Using 100 mg. of Banthine as a standard of reference, the doses of atropine, Bellafoline, Pamine, Elorine, and Pathilon that gave similar side effects (the equitoxic dose) were determined. This dose was found to be 2–8 times the amount usually used clinically or experimentally. The small-intestine antimotility activity of this dose was then measured by balloon kymography in the same subject. Considerable variation in degree of side effects, dose required to produce side effects, and antimotor response to a particular dosage of drug was observed from subject to subject.

Five experiments were conducted to study the effects of inhibiting growth of an implanted fibrosarcoma in randomly bred and inbred Irish gray rats by (1) adding essential fats to otherwise ineffective diets, and by (2) giving intraperitoneal injections of guinea pig serum.

No etiologic agent can be demonstrated in spite of thorough medical investigation in many patients suffering from chronic diarrhea. Among these patients are some who cause themselves to have chronic diarrhea by the surreptitious ingestion of laxatives. We would like to describe three such patients with self-induced diarrhea due to the ingestion of phenolphthalein-containing laxatives and to emphasize a simple method which allows detection of such patients. CASE 1. —A 34-year-old medical secretary was seen in consultation with a history of 18 years of intermittent diarrhea consisting of 6-8 liquid stools a day which occasionally contained mucus. Her 58-year-old mother had ulcerative colitis. The patient had been thought to have ulcerative colitis by competent gastroenterologists in another institution. On examination, she was found to be in better physical condition than her history would lead one to expect. Sigmoidoscopy was essentially normal with "questionable slight friability of the mucosa." A barium

Originally published in French, written by a Belgian radiologist, Dr. Marcel Brombart, in 1954, Clinical Radiology of the Oesophagus was translated into English by an Irish radiologist, Dr. Sheila Kenny, in 1961. The international aspects of this book are matched by the broad audience to which it is addressed: radiologists, gastroenterologists, otorhinologists, thoracic surgeons, and physicians.The radiographs are excellent technically as well as for the purpose of illustrating the various diseases. Also contained are extensive instructions as to radiographic techniques for examining the anatomic and neuromuscular disorders of the pharynx and esophagus. Many diagrammatic sketches are included which enhance and clarify the x-rays, the anatomy of the pharynx and esophagus, and the relationship of the adjacent structures to the esophagus.Since the writing of this monograph in 1954, a good deal of progress, however, has been made as to the physiology of the esophagus as well as the pathophysiology