University of Arkansas for Medical Sciences

About: University of Arkansas for Medical Sciences is a education organization based out in Little Rock, Arkansas, United States. It is known for research contribution in the topics: Population & Health care. The organization has 14077 authors who have published 26012 publications receiving 973592 citations. The organization is also known as: UAMS.

Aging-associated changes in human brain.

Abstract: A wide variety of anatomic and histological alterations are common in brains of aged individuals. However, identification of intrinsic aging changes--as distinct from changes resulting from cumulative environmental insult--is problematic. Some degree of neuronal and volume loss would appear to be inevitable, but recent studies have suggested that the magnitudes of such changes are much less than previously thought, and studies of dendritic complexity in cognitively intact individuals suggest continuing neuronal plasticity into the eighth decade. A number of vascular changes become more frequent with age, many attributable to systemic conditions such as hypertension and atherosclerosis. Age-associated vascular changes not clearly linked to such conditions include hyaline arteriosclerotic changes with formation of arterial tortuosities in small intracranial vessels and the radiographic changes in deep cerebral white matter known as "leukoaraiosis." Aging is accompanied by increases in glial cell activation, in oxidative damage to proteins and lipids, in irreversible protein glycation, and in damage to DNA, and such changes may underlie in part the age-associated increasing incidence of "degenerative" conditions such as Alzheimer disease and Parkinson disease. A small number of histological changes appear to be universal in aged human brains. These include increasing numbers of corpora amylacea within astrocytic processes near blood-brain or cerebrospinal fluid-brain interfaces, accumulation of the "aging" pigment lipofuscin in all brain regions, and appearance of Alzheimer-type neurofibrillary tangles (but not necessarily amyloid plaques) in mesial temporal structures.

Multiplex PCR Protocol for the Diagnosis of Staphylococcal Infection

Abstract: We report the development of a multiplex PCR protocol for the diagnosis of staphylococcal infection The protocol was designed to (i) detect any staphylococcal species to the exclusion of other bacterial pathogens (based on primers corresponding to Staphylococcus-specific regions of the 16S rRNA genes), (ii) distinguish between S aureus and the coagulase-negative staphylococci (CNS) (based on amplification of the S aureus-specific clfA gene), and (iii) provide an indication of the likelihood that the staphylococci present in the specimen are resistant to oxacillin (based on amplification of the mecA gene) The expected fragments were amplified from each of 60 staphylococcal isolates (13 oxacillin-resistant S aureus isolates, 23 oxacillin-sensitive S aureus isolates, 17 oxacillin-resistant CNS, and 7 oxacillin-sensitive CNS) No amplification products were observed with template DNA from nonstaphylococcal species, and the efficiency of amplification of staphylococcal targets was not adversely affected by the presence of DNA from other bacterial species in the same sample The utility of the protocol for the analysis of clinical samples was verified by analysis of aliquots taken directly from BacT/Alert blood culture bottles Of 77 blood cultures tested, only 7 yielded results inconsistent with those of conventional methods of diagnosis and susceptibility testing Of those, one was identified as a CNS species by PCR and S aureus by conventional methods We also identified two isolates that were mecA positive but were oxacillin sensitive according to conventional methods The other four samples failed to yield any amplification product even with a control set of primers corresponding to a conserved region of the eubacterial rRNA genes

The Modern Spectrum of Renal Biopsy Findings in Patients with Diabetes

Abstract: Summary Background and objectives Renal biopsies performed in diabetic patients are increasing in number and complexity. This study sought to determine the usefulness of renal biopsy in patients with diabetes and the predictability of diagnosing diabetic nephropathy (DN) versus nondiabetic renal disease (NDRD) from clinical and laboratory data. Design, setting, participants, & measurements To assess modern trends, a retrospective study was performed of clinical-pathologic findings in all patients with diabetes who had a biopsy in 2011. Among 2642 native kidney biopsies, 620 (23.5%) were from patients with diabetes. Results The cohort included 371 men (60.7%) aged a median (interquartile range) 62 years (52–69) with 10-year (5–15) duration of diabetes mellitus (DM). Median serum creatinine was 2.5 mg/dl (1.6–4.4), and 52% of patients had stage 4–5 CKD. On biopsy, 37% of patients had DN alone, 36% had NDRD alone, and 27% had DN plus NDRD. In NDRD alone, FSGS (22%), hypertensive nephrosclerosis (18%), acute tubular necrosis (ATN) (17%), IgA nephropathy (11%), membranous GN (8%), and pauci-immune GN (7%) comprised 80% of diagnoses, compared with ATN (43%), hypertensive nephrosclerosis (19%), FSGS (13%), and IgA nephropathy (7%) for DN plus NDRD. In multivariate analyses, longer duration of DM was associated with a greater likelihood of DN and a lower likelihood of NDRD: each added year of DM reduced the odds of NDRD by 5% (odds ratio, 0.95; 95% confidence interval, 0.91 to 0.98; P =0.004). DM duration ≥12 years was the best predictor (58% sensitivity, 73% specificity) of DN alone. Conclusions Approximately one-quarter of all renal biopsies are performed in patients with DM. Judicious use of renal biopsy has uncovered NDRD alone or superimposed on DN in the majority of such biopsies. ATN is emerging as an important category of NDRD, which has not been reported previously.

Assessing quality of life in patients with head and neck cancer: cross-validation of the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Head and Neck module (QLQ-H&N35).

Abstract: Objective To evaluate the reliability and validity of a new, disease-specific quality-of-life measure for patients with head and neck cancer: the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire—QLQ-H&N35. Design Cross-sectional study using questionnaire data and medical chart review. Setting Academic tertiary care otolaryngology clinic. Participants One hundred twenty ambulatory patients, including 30 patients with advanced head and neck cancer in each of the following stages of treatment: (1) prior to treatment, (2) during active treatment, (3) within 6 months of completing treatment, and (4) more than 6 months after completing treatment. In addition, (5) a comparison group of 40 patients without malignant disease was included (total sample, N=160). Main Outcome Measures Scores on EORTC Quality of Life Core Questionnaire (QLQ-C30) and head and neck module (QLQ-H&N35), Profile of Mood States, and Impact of Events Scale. Results The QLQ-H&N35 demonstrated acceptable reliability (internal consistency). It successfully discriminated between cancer patients and the comparison group, and among subgroups of cancer patients at different phases of treatment (construct validity). The instrument was sensitive to the effects of radiation treatment and to site of disease. Its low-to-moderate correlations with the EORTC core questionnaire indicated that the QLQ-H&N35 provided unique information (discriminant validity). Scores were significantly associated with a number of demographic variables. Conclusion Results support the use of this disease-specific measure to assess quality of life among patients with advanced head and neck cancer.

Glial-neuronal interactions in Alzheimer disease: progressive association of IL-1alpha+ microglia and S100beta+ astrocytes with neurofibrillary tangle stages.

Abstract: Activated microglia, overexpressing interleukin-1 (IL-1), and activated astrocytes, overexpressing S100beta, have been implicated in the formation and evolution of tau2-immunoreactive (tau2+) neuritic plaques in Alzheimer disease. In this study, we assessed the role of IL-1alpha+ microglia and S100beta+ astrocytes in the pathogenesis of another cardinal histopathological feature of Alzheimer disease: tau2+ neurofibrillary tangles. Four distinct stages of neurofibrillary tangle formation were identified: neurons with granular perikaryal tau2 immunoreactivity (stage 0); fibrillar neuronal inclusions (stage 1); dense, neuronal soma-filling inclusions (stage 2); and acellular, fibrillar deposits (stage 3, "ghost tangles"). The numbers of tangles in randomly selected fields of parahippocampal cortex from 11 Alzheimer patients correlated with both the numbers of IL-1alpha+ microglia and the numbers of S100beta+ astrocytes in these fields (r = 0.72, p < 0.02; r = 0.73, p = 0.01, respectively). There were progressive increases in frequency of association between tangle stages and both IL-1alpha+ microglia and S100beta+ astrocytes: 48, 56, 67, and 92% of stage 0-3 tangles, respectively, had associated IL-1alpha+ microglia; and 21, 37, 55, and 91% of stage 0-3 tangles had associated S100beta+ astrocytes. This progressive association of activated IL-1alpha+ microglia and activated S100beta+ astrocytes with tau2+ tangle stages suggests a role for glial-neuronal interactions in the degeneration of tangle-bearing neurons in Alzheimer disease.