New loci associated with kidney function and chronic kidney disease

Chronic kidney disease (CKD) is a significant public health problem, and recent genetic studies have identified common CKD susceptibility variants. The CKDGen consortium performed a meta-analysis of genome-wide association data in 67,093 individuals of European ancestry from 20 predominantly population-based studies in order to identify new susceptibility loci for reduced renal function as estimated by serum creatinine (eGFRcrea), serum cystatin c (eGFRcys) and CKD (eGFRcrea < 60 ml/min/1.73 m(2); n = 5,807 individuals with CKD (cases)). Follow-up of the 23 new genome-wide-significant loci (P < 5 x 10(-8)) in 22,982 replication samples identified 13 new loci affecting renal function and CKD (in or near LASS2, GCKR, ALMS1, TFDP2, DAB2, SLC34A1, VEGFA, PRKAG2, PIP5K1B, ATXN2, DACH1, UBE2Q2 and SLC7A9) and 7 loci suspected to affect creatinine production and secretion (CPS1, SLC22A2, TMEM60, WDR37, SLC6A13, WDR72 and BCAS3). These results further our understanding of the biologic mechanisms of kidney function by identifying loci that potentially influence nephrogenesis, podocyte function, angiogenesis, solute transport and metabolic functions of the kidney.

Tomographic mapping of human cerebral metabolism visual stimulation and deprivation

Positron computed tomography was used to investigate changes in the local cerebral metabolic rate for glucose (LCMRGlc) of the visual cortex. Progressive increases in LCMRGlc were found from eyes-closed control to stimulation with white light, alternating black/white checkerboard pattern, and a complex visual scene of a park, with the associative visual cortex increasing at a faster rate than the primary visual cortex as the visual scene complexity increased. A graded decrease in LCMRGlc of the visual cortex was found with a stepwise deletion of spontaneous cell firing at the retinal, geniculate and cortical level due to lesions. Left/right metabolic symmetry of the visual cortex during monocular stimulation confirms 50% crossing of the human visual system. Neonatal blindness showed no apparent degeneration of the visual cortex and was equivalent to eyes-closed controls. The interictal state of a patient with visual seizures demonstrated a hypometabolic visual cortex with a 2.5-fold increase in metabolism during an ictal visual hallucination.

Effects of estrogen status and aging on salivary flow rates in healthy Caucasian women

A comparison of salivary flow rates was made between three groups of female individuals according to their menopausal status. The three groups consisted of healthy, dentate, nonmedicated women (with the exception of the use of estrogen) from the Baltimore Longitudinal Study of Aging. One group consisted of premenopausal women (n = 51), their mean age was 39 years. Another group (n = 26) was perimenopausal with a mean age of 48 years. A third group (n = 76) was postmenopausal with a mean age of 69 years. The groups were evaluated for unstimulated (UPAR) and stimulated parotid gland flow rates (SPAR), unstimulated (USUB) and stimulated submandibular/sublingual gland flow rates (SSUB), and stimulated whole-saliva flow rates (SWHOLE). The parotid flow rates were determined using a Carlson-Crittenden cup, while the submandibular/sublingual flow rates were determined using the National Institute of Dental Research collector. A 2% citrate solution was used for stimulation in glandular collections. Chewing a 1-cm3 cube of paraffin was used to stimulate whole saliva. The results showed no significant differences in UPAR, SPAR, and SWHOLE between the three groups. However, the premenopausal women had higher USUB than the postmenopausal group. The premenopausal women also had higher SSUB than perimenopausal and postmenopausal groups. There were no differences in salivary flow rates between those taking estrogen and those that were not medicated.

Studies on angiotensinogen of plasma and cerebrospinal fluid in normal and hypertensive human subjects

The presence of a renin-angiotensin system in the central nervous system (CNS) has been demonstrated by several investigators, but little is known regarding the origin of its components. In this study we have compared the immunological and physical-chemical nature of angiotensinogen in plasma and cerebrospinal fluid (CSF) of human subjects and explored whether differences are present in CSF angiotensinogen concentrations of normal and hypertensive subjects. No significant differences in the nature of plasma and CSF angiotensinogen was observed with respect to molecular weight (65-70,000) electrophoretic mobility (RFalb = 0.67 plus or minus 0.003) or angiotensin I (AI) generated (pI = 6.6). Following isoelectric focusing, the plasma angiotensinogen was shown to consist of a single component with an isoionic point of 4.40 plus or minus 0.04. CSF angiotensinogen, on the other hand, resolved into three components (pI = 4.76 plus or minus 0.02; 5.16 plus or minus 0.04; 5.76 plus or minus 0.04). Although no correlations were observed between angiotensinogen levels in the CSF or plasma with blood pressure (BP), a statistically significant difference in angiotensinogen concentration of both plasma and CSF was observed between normotensive and hypertensive subjects. The differences in the chemical and immunological nature of human plasma and CSF angiotensinogens suggest that the angiotensinogen of CSF is not of peripheral origin.

Impaired glucose tolerance in midlife and longitudinal changes in brain function during aging

We investigated whether individuals with impaired glucose tolerance (IGT) in midlife subsequently show regionally specific longitudinal changes in regional cerebral blood flow (rCBF) relative to those with normal glucose tolerance (NGT). Sixty-four cognitively normal participants in the neuroimaging substudy of the Baltimore Longitudinal Study of Aging underwent serial (15)O-water positron emission tomography scans (age at first scan, 69.6 ± 7.5 years) and oral glucose tolerance tests 12 years earlier (age at first oral glucose tolerance test, 57.2 ± 11.1 years). Using voxel-based analysis, we compared changes in rCBF over an 8-year period between 15 participants with IGT in midlife and 49 with NGT. Significant differences were observed in longitudinal change in rCBF between the IGT and NGT groups. The predominant pattern was greater rCBF decline in the IGT group in the frontal, parietal, and temporal cortices. Some brain regions in the frontal and temporal cortices also showed greater longitudinal increments in rCBF in the IGT group. Our findings suggest that IGT in midlife is associated with subsequent longitudinal changes in brain function during aging even in cognitively normal older individuals.

Working group recommendations: measuring outcomes of care in geriatric evaluation and management units

Issues related to measuring outcomes of care in geriatric evaluation and management (GEM) units were identified by the outcomes working group of the GEM evaluation conference. GEM units have as a major goal the improvement or maintenance of both physical and psychosocial function. Suggested outcome measures for physical health included survival, restricted activity days, general health perceptions, comprehensive physical function, and miscellaneous specific types of functioning. In the area of psycho-social function, the working group suggested measuring cognitive function, affect/life satisfaction, social function, and satisfaction with care. The patient's caregiver (eg, spouse or child) is often an important target of GEM care, and the group suggested measuring caregiver burden, life satisfaction, and assessment of patient behavior problems. While the primary goal of GEM units is to improve health status, their effects on the utilization and cost of health care are important to decisions about wide-spread implementation and funding. The group therefore suggested a comprehensive assessment of these outcomes. Among the large array of recommended outcomes, the most important were thought to be mortality, function, and cost.

Anaplastic large cell (Ki-1) lymphoma with histiocytic phenotype simulating carcinoma

Histiocytic and epithelial cell types share many cytomorphologic and functional characteristics; it is predictable, therefore, that corresponding malignancies might be difficult to distinguish. Described is the case of a 52-year-old woman in whom disseminated anaplastic large-cell lymphoma simulated carcinomatosis by conventional morphologic criteria. Evidence of histiocytic differentiation was derived from immunocytochemical, fine structural, and genetic probe analyses. The diagnosis of histiocytic neoplasia is discussed in relation to categories previously termed malignant histiocytosis, "Ki-1" lymphoma, and regressing atypical histiocytosis, and comparisons are made with animal tumor models.

Alcohol consumption and premotor corpus callosum in older adults

Heavy alcohol consumption is toxic to the brain, especially to the frontal white matter (WM), but whether lesser amounts of alcohol negatively impact the brain WM is unclear. In this study, we examined the relationship between self-reported alcohol consumption and regional WM and grey matter (GM) volume in fifty-six men and thirty-seven women (70+- 7years) cognitively intact participants of the Baltimore Longitudinal Study of Aging (BLSA) with no history of alcohol abuse. We used regional analysis of volumes examined in normalized space (RAVENS) maps methodology for WM and GM segmentation and normalization followed by voxel based morphometry (VBM) implemented in SPM8 to examine the cross-sectional association between alcohol consumption and regional WM (and, separately, GM) volume controlling for age, sex, smoking, blood pressure and dietary thiamine intake. WM VBM revealed that in men, but not in women, higher alcohol consumption was associated with lower volume in premotor frontal corpus callosum. This finding suggests that even moderate amounts of alcohol may be detrimental to corpus callosum and white matter integrity.

Tissue-specific hypomethylation of the human c-K-ras gene

Methylation of the c-K-ras gene was examined in a wide variety of human tissues using the methylation sensitive restriction endonuclease HpaII. All tissues showed hypomethylation in the region of exon zero. Specific hypomethylation of a particular HpaII site in the second intron was observed in gastrointestinal and tracheobronchial epithelial cell DNAs. Specific hypomethylation was also observed in a cluster of HpaII sites within the first intron in sperm, endometrium and placenta DNAs. These regions were predominantly methylated in a wide variety of other tissues, including fetal gut. The possible implications are discussed.

Retropharyngeal Hematoma Causing Airway Compromise After Tissue Plasminogen Activator Administration: A Case Report

INTRODUCTION

Tissue plasminogen activator (tPA), commonly used for treatment of acute ischemic stroke, is associated with life-threatening bleeding intracranially as well as surrounding the airway.

CASE REPORT

A 78-year-old year old male who presented with stroke symptoms and after tPA administration developed a retropharyngeal hematoma requiring intubation and surgical intervention.

CONCLUSION

Numerous threats to the patient's airway can develop after tPA administration. While angioedema is the most common cause, it is important to be prepared for other causes related to hemorrhage.

Analysis of human TCRβ repertoire by a RARE-sequencing method reveals distinct features of TCRβ diversity and distribution and their alterations with age (IRM10P.758)

The T cell receptor (TCR) repertoire (diversity and distribution) is a vital parameter of the overall function of T cells. Reduction of TCR diversity and alteration of TCR distribution is believed to occur with age and acts as a major contributor for age-associated decline of immune function. However, neither the actual size of the TCR repertoire nor its precise age-related change have been directly determined. Applying a RACE-next generation sequencing (RAP-Seq) method, we assessed the TCRβ repertoire of blood CD4+ and CD8+ T cells of 13 adults (21-94 years old) including 6 adults with longitudinal samples. We found that TCRβ diversity of CD4+ T cells is 3-4 times greater than CD8+ T cells. TCRβ CDR3 was distinct between CD4+ and CD8+ T cells with preferential amino acid usage. Reduced TCRβ diversity and expanded highly abundant TCRβ clones occurred from middle to old subjects (45-75 years old) but not in very old subjects (80-94 years old). Together, these findings reveal the distinct features and actual age-associated changes of TCRβ repertoire, which could serve as a measure of the immune competency and a guide for the clinical intervention in older humans.