University of Maryland, Baltimore

About: University of Maryland, Baltimore is a education organization based out in Baltimore, Maryland, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 35249 authors who have published 64702 publications receiving 2936441 citations. The organization is also known as: UMAB & UMB.

Crypt- and Mucosa-Associated Core Microbiotas in Humans and Their Alteration in Colon Cancer Patients

Abstract: We have previously identified a crypt-specific core microbiota (CSCM) in the colons of healthy laboratory mice and related wild rodents. Here, we confirm that a CSCM also exists in the human colon and appears to be altered during colon cancer. The colonic microbiota is suggested to be involved in the development of colorectal cancer (CRC). Because the microbiota identified in fecal samples from CRC patients does not directly reflect the microbiota associated with tumor tissues themselves, we sought to characterize the bacterial communities from the crypts and associated adjacent mucosal surfaces of 58 patients (tumor and normal homologous tissue) and 9 controls with normal colonoscopy results. Here, we confirm that bacteria colonize human colonic crypts in both control and CRC tissues, and using laser-microdissected tissues and 16S rRNA gene sequencing, we further show that right and left crypt- and mucosa-associated bacterial communities are significantly different. In addition to Bacteroidetes and Firmicutes, and as with murine proximal colon crypts, environmental nonfermentative Proteobacteria are found in human colonic crypts. Fusobacterium and Bacteroides fragilis are more abundant in right-side tumors, whereas Parvimonas micra is more prevalent in left-side tumors. More precisely, Fusobacterium periodonticum is more abundant in crypts from cancerous samples in the right colon than in associated nontumoral samples from adjacent areas but not in left-side colonic samples. Future analysis of the interaction between these bacteria and the crypt epithelium, particularly intestinal stem cells, will allow deciphering of their possible oncogenic potential.IMPORTANCE Due to the huge number of bacteria constituting the human colon microbiota, alteration in the balance of its constitutive taxa (i.e., dysbiosis) is highly suspected of being involved in colorectal oncogenesis. Indeed, bacterial signatures in association with CRC have been described. These signatures may vary if bacteria are identified in feces or in association with tumor tissues. Here, we show that bacteria colonize human colonic crypts in tissues obtained from patients with CRC and with normal colonoscopy results. Aerobic nonfermentative Proteobacteria previously identified as constitutive of the crypt-specific core microbiota in murine colonic samples are similarly prevalent in human colonic crypts in combination with other anaerobic taxa. We also show that bacterial signatures characterizing the crypts of colonic tumors vary depending whether right-side or left-side tumors are analyzed.

Early Adolescent Risk Behavior Outcomes of Childhood Externalizing Behavioral Trajectories

Abstract: Little is known about the early childhood indicators of adolescent risk. The link between trajectories of externalizing behavioral problems and early adolescent risk behavior was examined in a longitudinal sample of 875 child participants in the LONGSCAN studies. Five trajectory groups of children defined by externalizing behavior problems were identified: Low, Low-Medium, Moderate, Increasing-High, and High. After controlling for demographics and maltreatment, violent/delinquent behavior was significantly predicted by membership in the Moderate and Increasing-High problem behavior groups. Substance use in early adolescence was significantly predicted by membership in the High behavior problem group. These findings suggest that there is a great deal of continuity between patterns of externalizing behavior in childhood and risk-taking in early adolescence. Understanding the course of externalizing behavior in childhood can help identify children at particular risk for more serious behavioral problems in early adolescence.

Descending influences from the lateral hypothalamus and amygdala converge onto medullary taste neurons.

Abstract: The lateral hypothalamus (LH) and the central nucleus of the amygdala (CeA) exert an influence on many aspects of ingestive behavior. These nuclei receive projections from several areas carrying gustatory and viscerosensory information, and send axons to these nuclei as well, including the nucleus of the solitary tract (NST). Gustatory responses of NST neurons are modulated by stimulation of the LH and the CeA, and by several physiological factors related to ingestive behavior. We investigated the effect of both LH and CeA stimulation on the activity of 215 taste-responsive neurons in the hamster NST. More than half of these neurons (113/215) were modulated by electrical stimulation of the LH and/or CeA; of these, 52 cells were influenced by both areas, often bilaterally. The LH influenced more neurons than the CeA (101 versus 64 cells). Contralateral stimulation of these forebrain areas was more often effective (144 responses) than ipsilateral (74). Modulatory effects were mostly excitatory (102 cells); 11 cells were inhibited, mostly by ipsilateral LH stimulation. A subset of these cells (n = 25) was examined for the effects of microinjection of DL-homocysteic acid (DLH), a glutamate receptor agonist, into the LH and/or CeA. The effects of electrical stimulation were completely mimicked by DLH, indicating that cell somata in and around the stimulating sites were responsible for these effects. Other cells (n = 25) were tested for the effects of electrical stimulation of the LH and/or CeA on the responses to taste stimulation of the tongue (32 mM sucrose, NaCl and quinine hydrochloride, and 3.2 mM citric acid). Responses to taste stimuli were enhanced by the excitatory influence of the LH and/or CeA. These data demonstrate that descending influences from the LH and CeA reach many of the same cells in the gustatory NST and can modulate their responses to taste stimulation.

Visceral adiposity, increased adipocyte lipolysis, and metabolic dysfunction in obese postmenopausal women.

Abstract: This study determines whether there are regional differences in lipolysis and whether adipocyte lipolysis is associated with the degree of visceral adiposity and its metabolic complications in 32 o...

Relationship between aggressive behaviors and depression among nursing home residents with dementia.

Abstract: Background Verbal and physical aggression are common behavior problems among nursing home residents with dementia. Depression among nursing home residents is also a common but underdiagnosed disorder. Method Data collected on 1101 residents with dementia, newly admitted to a sample of 59 nursing homes across Maryland, were analyzed to determine if there was a relationship between depression and physical and verbal aggression. Results Residents with dementia who manifested physical or verbal aggression had a higher prevalence of depression than those without such behaviors (p<0.05). Conclusions Our findings suggest that nursing home residents with aggressive behaviors should be screened for depression and treated. Copyright © 2001 John Wiley & Sons, Ltd.