20608339
Vitamin D, proteinuria, diabetic nephropathy, and progression of CKD.
Although the endocrine effects of vitamin D are widely recognized, somewhat less appreciated is that vitamin D may serve paracrine functions through local activation by 1-alpha-hydroxylase and thus maintain immunity, vascular function, cardiomyocyte health, and abrogate inflammation and insulin resistance. In the kidney, vitamin D may be important for maintaining podocyte health, preventing epithelial-to-mesenchymal transformation, and suppressing renin gene expression and inflammation. Replacement with pharmacologic dosages of vitamin D receptor agonists (VDRA) in animal models of kidney disease consistently show reduction in albuminuria, abrogation of glomerulosclerosis, glomerulomegaly, and glomerular inflammation, effects that may be independent of BP and parathyroid hormone, but the effects of VDRA in preventing tubulointerstitial fibrosis and preventing the progression of kidney failure in these animal models are less clear. Emerging evidence in patients with chronic kidney disease (CKD) show that vitamin D can reduce proteinuria or albuminuria even in the presence of angiotensin-converting enzyme inhibition. In addition to reducing proteinuria, VDRA may reduce insulin resistance, BP, and inflammation and preserve podocyte loss providing biologic plausibility to the notion that the use of VDRA may be associated with salubrious outcomes in patients with diabetic nephropathy. Patients with CKD have a very high prevalence of deficiency of 25-hydroxyvitamin D. Whether pharmacologic dosages of vitamin D instead of VDRA in patients with CKD can overcome the paracrine and endocrine functions of this vitamin remains unknown. To demonstrate the putative benefits of native vitamin D and VDRA among patients with CKD, randomized, controlled trials are needed.
22176722
Alar web in cleft lip nose deformity: study in adult unilateral clefts.
BACKGROUND
The correction of alar webbing in unilateral cleft lip nose deformity is challenging because of progressive distortions in the alar web region during the period of growth. Alar webbing is a persistent universal deformity in both the primary and secondary cleft lip noses. The purpose of this article is to study the alar web deformity in adult patients with unilateral cleft lip noses.


METHODS
Twenty-five patients aged 13 years and older presenting with unilateral cleft nasal deformity were included. Preoperative and postoperative measurements of the nose, along with detailed intraoperative recording of the deformed anatomy, were done. Preoperative magnetic resonance imaging was also done in selected cases. Transcolumellar open rhinoplasty was performed in all the cases, and nasal septal straightening with centralization was done. Cleft alar base augmentation was done using bone graft to restore symmetry of the nasal tripod. Both the cleft and noncleft alar cartilages were extensively mobilized from the skin and mucosal sides. The overgrown and caudally slumped cleft-side alar cartilage was resected caudally and was then resuspended in a symmetrical position with the noncleft alar cartilage. A midline-strut septal cartilage extension graft was used to restore the tip aesthetics. The skin overlying the alar web was in-rolled after semilunar cartilage resection, and skin excision was also done to restore symmetry with the opposite vestibule. The remaining secondary cleft nasal and lip deformities were corrected depending upon the specific presenting pathologic abnormality.


RESULTS
The cleft alar cartilage was found to be caudally displaced in all the cases. The caudal border of the lateral crus was prolapsing in the cavity of the vestibule on the superomedial aspect and was tenting the skin in the area of the weak triangle, producing the characteristic alar web deformity. In the study group, the maximum width of the cleft alar cartilage at the level of the lateral crus was increased by approximately 4 mm when compared with the noncleft alar cartilage. The before- and after-rhinoplasty surgery results were objectively assessed using a patient, surgeon, and independent observer survey. The cosmetic result of the nasal tip complex was found to be very good and good (90%), satisfactory (5%), and poor (5%) in patients.


CONCLUSIONS
The alar web in unilateral cleft lip nose deformity is the result of caudal overgrowth and migration of the alar cartilage. The caudal edge of the prolapsed lateral crus overhangs the cleft-side nasal aperture on its superomedial aspect, producing this deformity. Satisfactory correction of this deformity should envisage caudal resection and repositioning of the dislocated alar cartilage along with caudal resection of the lateral crus with in-rolling of the skin after resection to achieve symmetric results in unilateral cleft lip rhinoplasty.
36005104
Volume Overload in Dialysis: The Elephant in the Room, No One Can See
interests of the authors. However, considering the totality of the evidence, I am less convinced that this marker is superior to other volume markers. First, there are few head-to-head studies comparing BIA to other established markers of volume. Second, there is no range that defines ‘normal’. Unlike blood pressure (BP) or cholesterol, there is no target that has been established. The normal values are obtained from healthy subjects whose body composition differs substantially from those on dialysis. Extrapolating from healthy subjects to those with ESRD on hemodialysis does not appear scientifically valid. Third, there is no study to my knowledge that demonstrates convincingly that compared to probing dry weight without BIA, BIA-guided dry weight reduction results in improved outcomes. Most data provided to support the use of BIA are associative and observational. A large amount of observational data does not prove causation. We therefore have to be cautious in interpreting these data as ‘strongly indicative of fluid overload’. Nearly all markers of volemia suffer from the same shortcomings. These shortcomings include lack of normative data, and data being largely observational and associative in nature. As an example, several observational studies suggest that B-type natriuretic peptide (BNP), NT-proBNP or other natriuretic peptides are associated with volume state among people with ESRD on dialysis [2–10] . However, only one study has been reported to date that relates the change in BNP to an intervention of probing dry weight [11] . In this study, a direct relationship existed at baseline between BNP and interdialytic ambulatory BP. Since interdialytic ambulatory BP is reVolume overload is the invisible threat to the health of dialysis patients. Currently, Medicare incentivizes the measurement of the dose of dialysis (urea reduction ratio) but has no measure of volume. Perhaps this is because the few who can recognize the epidemic nature of volume excess cannot agree on how to define it. Whereas, some have proposed interdialytic weight gain (IDWG) as a marker of volume, the in-depth review of Hecking et al. [1] quite clearly and importantly makes the distinction that IDWG should not be confused with hypervolemia. One has to wonder how IDWG got confused with dry weight in the first place. It appears that epidemiologists decided to use IDWG as a proxy of dry weight because of its ready availability in large databases. IDWG is a marker that is convenient; it can be measured easily and it can be related to outcomes such as all-cause mortality. This analysis was performed and a relationship emerged between IDWG and all-cause mortality. But establishing a relationship between IDWG and mortality does not establish causality. It could be numerous other factors, measured and unmeasured, associated with IDWG which may be causally related to mortality. Factors such as missing or cutting short dialysis, not taking medications as prescribed, and consuming a diet rich in phosphorus and potassium are some confounding factors that may also be associated with IDWG but may be more plausibly related to mortality. The authors discuss several markers of volume excess. Although several exist, one marker, bioimpedance analysis (BIA), is discussed in great detail. This is understandable given both the academic and intellectual property Published online: July 6, 2013 Nephrology American Journal of
191311
Assessment of iothalamate plasma clearance: duration of study affects quality of GFR.
BACKGROUND AND OBJECTIVES
Measurement of GFR is important for the management of chronic kidney disease (CKD). Although bolus administration of radiocontrast agents is commonly used to measure GFR, the optimal duration of sampling to assess their plasma clearance is unknown. The purpose of this study was to evaluate whether the duration of plasma sampling influences precision and estimation of GFR.


DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS
GFR was measured by sampling plasma 12 times over 5 h in 56 patients with CKD (mean age 64 yr, 98% men, 79% Caucasian, 34% diabetics, estimated GFR 31.8 +/- 14.2 ml/min/1.73 m(2)). In a subset of 12 patients we measured GFR by sampling plasma 17 times over 10 h.


RESULTS
Short sampling intervals considerably overestimated GFR measured using total plasma iothalamate clearance, especially in larger patients. In the higher estimated GFR group (>30 ml/min/1.73 m(2)), the 5-h GFR was 17% higher and 2-h GFR 54% higher compared with the 10-h GFR, which averaged 40.3 ml/min/1.73 m(2). In the lower estimated GFR group (<30 ml/min/1.73 m(2)), the 5-h GFR was 36% higher and 2-h GFR 126% higher compared with the 10-h GFR, which averaged 22.2 ml/min/1.73 m(2). Short sampling duration also reduced the precision of the estimated GFR from 1.67% for 10-h GFR, to 3.48% for 5-h GFR, and to 7.07% for 2-h GFR.


CONCLUSIONS
GFR measured over a longer duration with multiple plasma samples spanning the distribution and elimination phases may improve precision and provide a better measure of renal function.
11453581
Proinflammatory effects of oxidative stress in chronic kidney disease: role of additional angiotensin II blockade.
Oxidative stress plays an important role in causing progressive chronic kidney disease (CKD). We examined the influence of add-on ANG II receptor blockade administered as losartan (50 mg/day for 1 mo) on oxidative stress and proinflammatory state of the kidney in patients with CKD. All subjects were taking an angiotensin-converting enzyme inhibitor plus other antihypertensive agents. Oxidative stress to lipids and proteins was measured by an HPLC assay for malondialdehyde (MDA) and carbonyl concentration, respectively. Urinary inflammation was measured by monocyte chemotactic protein-1 (MCP-1) excretion rate. The etiology of CKD was type 2 diabetes mellitus in 12 and glomerulonephritis in 4 patients. There was no change in proteinuria or 24-h ambulatory blood pressure (BP) with add-on ANG II receptor blockade with losartan therapy. Before losartan therapy, urinary protein and albumin oxidation were 99 and 71% higher, respectively, compared with in plasma (P < 0.05). There was a 35% reduction in urinary oxidized albumin with add-on losartan therapy (P = 0.036). Urinary and plasma MDA were elevated compared with age-matched controls. Urinary MDA was significantly reduced from 4.75 +/- 3.23 to 3.39 +/- 2.17 micromol/g creatinine with add-on losartan therapy. However, plasma MDA or oxidized proteins did not change in response to additional ANG II blockade. A good correlation was seen between the change in urinary oxidized albumin and MCP-1 levels (r = 0.61, P = 0.012). These data demonstrate that oxidative damage to urinary protein and lipids can be reduced with additional ANG II receptor blockade, independently of reductions in proteinuria or BP. Urinary measurements of markers of oxidative damage to lipids and proteins appear to be more sensitive than plasma measurements in patients with CKD. The significant association of the change in urinary MCP-1 with a reduction in oxidative stress supports the role of the redox state in the kidney with renal fibrosis and progressive kidney damage.
24249726
Regulation of circadian blood pressure: from mice to astronauts.
PURPOSE OF REVIEW
Circadian variation is commonly seen in healthy people; aberration in these biological rhythms is an early sign of disease. Impaired circadian variation of blood pressure (BP) has been shown to be associated with greater target organ damage and with an elevated risk of cardiovascular events independent of the BP load. The purpose of this review is to examine the physiology of circadian BP variation and propose a tripartite model that explains the regulation of circadian BP.


RECENT FINDINGS
The time-keeper in mammals resides centrally in the suprachiasmatic nucleus. Apart from this central clock, molecular clocks exist in most peripheral tissues including vascular tissue and the kidney. These molecular clocks regulate sodium balance, sympathetic function and vascular tone. A physiological model is proposed that integrates our understanding of molecular clocks in mice with the circadian BP variation among humans. The master regulator in this proposed model is the sleep-activity cycle. The equivalents of peripheral clocks are endothelial and adrenergic functions. Thus, in the proposed model, the variation in circadian BP is dependent upon three major factors: physical activity, autonomic function, and sodium sensitivity.


SUMMARY
The integrated consideration of physical activity, autonomic function, and sodium sensitivity appears to explain the physiology of circadian BP variation and the pathophysiology of disrupted BP rhythms in various conditions and disease states. Our understanding of molecular clocks in mice may help to explain the provenance of blunted circadian BP variation even among astronauts.
40656023
Temperature-induced changes in the flexibility of the loop between SH1 (Cys-707) and SH3 (Cys-522) in myosin subfragment 1 detected by cross-linking.
The ability of dibromobimane to cross-link SH1 (Cys-707) in the 21-kDa C-terminal segment to SH3 (Cys-522) in the 50-kDa middle segment of the myosin S1 heavy chain has been examined as a function of nucleotide binding and temperature. The results obtained indicate that, while the reagent rapidly reacts with SH1 at both 25 and 4 degrees C, its ability to cross-link to SH3 is highly dependent on temperature. At 25 degrees C, substantial cross-linking from monofunctionally labeled SH1 to SH3 occurs, in agreement with recent work of Mornet, Ue, and Morales (1985, Proc. Natl. Acad. Sci, USA 82, 1658-1662) and of Ue (1987, Biochemistry 26, 1889-1894) and with their conclusion that a loop, allowing SH1 and SH3 to reside at the cross-linking span of dibromobimane, preexists in the protein. At 4 degrees C, however, negligible amounts of cross-linking are observed whether or not a nucleotide is present, despite indications that SH1 is labeled rapidly by the reagent at this temperature. The inability to form this cross-link is not due to an alternate cross-link between monofunctionally labeled SH1 and another thiol in the 21-kDa segment. These results indicate that this loop exists at 25 degrees C and does not exist (or exists only transiently) at the lower temperature.
9534946
Tuberculous dilated cardiomyopathy: an under-recognized entity?
BackgroundTuberculosis (TB) is a common public health problem in many parts of the world. TB is generally believed to spare these four organs-heart, skeletal muscle, thyroid and pancreas. We describe a rare case of myocardial TB diagnosed on a post-mortem cardiac biopsy.Case presentationPatient presented with history suggestive of congestive heart failure. We describe the clinical presentation, investigations and outcome of this case, and review the literature on the involvement of myocardium by TB.ConclusionInvolvement of myocardium by TB is rare. However it should be suspected as a cause of congestive heart failure in any patient with features suggestive of TB. Increasing recognition of the entity and the use of endomyocardial biopsy may help us detect more cases of this "curable" form of cardiomyopathy.
6766565
Case 3-2007: a boy with respiratory insufficiency.
n engl j med 356;22 www.nejm.org may 31, 2007 2329 To the Editor: In the Case Record of a patient with respiratory insufficiency, presented by Boyer et al. (Jan. 25 issue),1 the discussants do not mention a condition known to be associated with idiopathic pulmonary hemosiderosis and to have implications for its management: celiac disease. The association is referred to as the Lane–Hamilton syndrome.2 It is important to recognize this condition, since treatment of celiac disease with a gluten-free diet could lead to the remission of idiopathic pulmonary hemosiderosis.3 Although both celiac disease and idiopathic pulmonary hemosiderosis are believed to be immunologically mediated, the pathogenetic link between them is not clear. A recent systematic review identified 20 patients with the Lane–Hamilton syndrome.4 Of these, 16 had been prescribed a gluten-free diet, with improvement documented in 12. Patients with idiopathic pulmonary hemosiderosis should be screened for celiac disease, even in the absence of gastrointestinal symptoms, by means of serologic testing for antiendomysial antibodies. If the test is positive, an intestinal biopsy should be carried out to confirm the disease, because a gluten-free diet is very effective for the regression of both celiac disease and idiopathic pulmonary hemosiderosis.
39481152
Magnesium deficiency: does it have a role to play in cataractogenesis?
Magnesium is one of the most important regulatory cation involved in several biological processes. It is important for maintaining the structural and functional integrity of vital ocular tissues such as lens. Presence of high magnesium content especially in the peripheral part of lens as compared to aqueous and vitreous humor has been observed. Magnesium plays significant role as a cofactor for more than 350 enzymes in the body especially those utilizing ATP. Membrane associated ATPase functions that are crucial in regulating the intracellular ionic environment, are magnesium-dependent. Moreover, the enzymes involved in ATP production and hydrolysis are also magnesium-dependent. Magnesium deficiency by interfering with ATPase functions causes increased intracellular calcium and sodium and decreases intracellular potassium concentration. Furthermore, magnesium deficiency is associated with increased oxidative stress secondary to increased expression of inducible nitric oxide synthase and increased production of nitric oxide. Thus the alterations in lenticular redox status and ionic imbalances form the basis of the association of magnesium deficiency with cataract. In this paper we review the mechanisms involved in magnesium homeostasis and the role of magnesium deficiency in the pathogenesis of cataract.
11594402
Intraocular Pressure-Lowering Activity of Topical Application of Aegle Marmelos Fruit Extract in Experimental Animal Models
Aim: The present study was designed to evaluate the intraocular pressure (IOP)-lowering activity of topical application of the aqueous extract of Aegle marmelos fruit in experimental animal models. Materials and Methods: New Zealand white rabbits with normal and experimentally elevated IOP using water loading and steroid-induced models were included in this study. The IOP-lowering effect of A. marmelos fruit extract in rabbits with experimentally elevated IOP was also compared with that of timolol 0.25%. Results: In rabbits with normal IOP, the A. marmelos fruit extract at a concentration of 1% showed the maximum IOP-lowering effect with 22.81% reduction from baseline IOP. The maximum IOP reduction achieved in water loading and steroid-induced models with the same concentration of A. marmelos was 27.57 and 28.41% from baseline, respectively. The efficacy was comparable to that of timolol after 45 min of water loading in the water loading model, and during the first 2 h of treatment in the steroid-induced model. Conclusion: A. marmelos fruit extract showed significant IOP-lowering activity in experimental animal models.