Aldosterone-mediated regulation of ENaC α, β, and γ subunit proteins in rat kidney

Aldosterone stimulates sodium transport in the renal collecting duct by activating the epithelial sodium channel (ENaC). To investigate the basis of this effect, we have developed a novel set of rabbit polyclonal antibodies to the 3 subunits of ENaC and have determined the abundance and distribution of ENaC subunits in the principal cells of the rat renal collecting duct. Elevated circulating aldosterone (due to either dietary NaCl restriction or aldosterone infusion) markedly increased the abundance of alphaENaC protein without increasing the abundance of the beta and gamma subunits. Thus, alphaENaC is selectively induced by aldosterone. In addition, immunofluorescence immunolocalization showed a striking redistribution in ENaC labeling to the apical region of the collecting duct principal cells. Finally, aldosterone induced a shift in molecular weight of gammaENaC from 85 kDa to 70 kDa, consistent with physiological proteolytic clipping of the extracellular loop as postulated previously. Thus, at the protein level, the response of ENaC to aldosterone stimulation is heterogenous, with both quantitative and qualitative changes that can explain observed increases in ENaC-mediated sodium transport.     

Pronator Quadratus Hemangioma (PQH): A Rare Case Report and Review

The intramuscular hemangioma is a rare clinical entity in the upper extremity. Pronator quadratus hemangioma poses a considerable morbidity in the functional quality of life of an individual. MRI remains the gold standard modality in diagnosing this rare entity. Additionally, histopathological examination of the lesion corroborates for the same. PQH follows an individualized protocol in the management of the tumour. A 35-year-old female presented with pain over her right wrist from past 1 year which was dull aching, non-radiating, localised to the palmar aspect of distal 1/3rd of the right forearm. There was no history of trauma or infection over the right wrist. Swelling was present over the palmar aspect of distal 1/3rd of right forearm, which was non-pulsatile, non-fluctuant, non-transilluminant, non-compressible, non-reducible and skin over the swelling was pinchable. The movements of the right wrist were painful and restricted. There was no distal neurovascular deficit. The MRI of her right wrist and hand suggested the presence of low flow vascular malformation within pronator quadratus muscle. The patient underwent excision biopsy of pronator quadratus in toto without any neurological complications. No recurrence was noted in the follow-up period for 12 months. The pronator quadratus hemangioma is a rare clinical entity where the natural course of disease and pathophysiology remains controversial. MRI serves as the gold standard in the diagnosis of intramuscular hemangioma. The management of such tumour has to be individualized based on the functional needs of the patient. The natural course of the disease has to be elicited to decrease the morbidity and enhance the functional quality of life of the patient.     

Evidence for two different modes of tripeptide disappearance in human intestine. Uptake by peptide carrier systems and hydrolysis by peptide hydrolases.

The intestinal fate of two tripeptides (triglycine and trileucine), which differ markedly in solubility and molecular weight, have been investigated by jejunal perfusion in healthy human volunteers. Rates of glycine or leucine uptake from test solutions containing triglycine or trileucine were greater than from test solutions containing corresponding amounts of free glycine or free leucine, respectively. The rate of glycine uptake from a 100 mM triglycine solution was greater than that from a 150 mM diglycine solution. At each infused load of triglycine (e.g., 1,000 mumol/min) the rates (micromoles/minutes per 30 cm) of either triglycine disappearance (810 +/- 40) or glycine absorption (2,208 +/- 122) were markedly greater than the luminal accumulation rates of either diglycine (56 +/- 10) or free glycine (110 +/- 18). The luminal accumulation rate of free leucine during infusion of a 5 mM trileucine solution was over threefold greater than that of free glycine during the infusion of a 5 mM triglycine solution. Luminal fluid exhibited no hydrolytic activity against triglycine, but contained some activity against trileucine. Saturation of free amino acid carrier system with a large load of leucine did not affect glycine absorption rate from a triglycine test solution, but isoleucine markedly inhibited the uptake from a trileucine solution. When the carrier system for dipeptides was saturated with a large amount of glycylleucine, the disappearance rate of triglycine was considerably reduced while that of trileucine remained unaffected. After addition of glycylleucine to tripeptide solutions, there was a minimal increase in the luminal accumulation of diglycine, while dileucine accumulation was incresed by 62-fold.     

Hyalinizing clear cell carcinoma of the base of tongue: a distinct and rare entity

Hyalinizing clear cell carcinoma (HCCC) of tongue is a rare neoplasm originating from minor salivary glands. We present a case of HCCC involving the base of tongue, in a 73-year-old male, clinically diagnosed as fibroma. Laser excision of the mass was done. Histopathological examination showed an infiltrating lesion composed predominantly of clear cells. The differential diagnosis included other salivary gland lesions having a clear cell component and metastatic clear cell renal carcinoma. Immunohistochemistry was useful in ruling out these lesions exhibiting clear cell component from clear cell carcinoma. Imaging studies revealed no lesion in either kidney. Since, HCCC has a better prognosis and the adequate treatment is wide excision, it needs to be differentiated from other carcinomas with clear cells. No further therapy was given to the patient. One year after the surgery, the patient is symptom free without local recurrence and on regular follow up.     

Timing of surgery for hip fractures: A systematic review of 52 published studies involving 291,413 patients

In order to define the optimum timing of surgery for a hip fracture, we performed a systematic review of published evidence. Data was extracted by two independent reviewers and the methodology of each study was assessed. Fifty-two studies involving 291,413 patients were identified. Outcomes measured were mortality, post-operative complications, length of hospital stay and percentage of patients discharged home.We found no randomised trials. For the 25 studies involving 282,470 participants that undertook adjustment for confounding factors, early surgery was associated with a reduced hospital stay. These studies produced conflicting results regarding mortality and morbidity being increased or unaffected by delaying surgery. None of these studies reported any adverse outcomes for early surgery. Those studies with more careful methodology were less likely to report a beneficial effect of early surgery, particularly in relation to mortality.In conclusion early surgery (within 48 h of admission) after a hip fracture reduces hospital stay and may also reduce complications and mortality.     

Localization of VP28 on the baculovirus envelope and its immunogenicity against white spot syndrome virus in Penaeus monodon

White spot syndrome virus (WSSV) is a large dsDNA virus responsible for white spot disease in shrimp and other crustaceans. VP28 is one of the major envelope proteins of WSSV and plays a crucial role in viral infection. In an effort to develop a vaccine against WSSV, we have constructed a recombinant baculovirus with an immediate early promoter 1 which expresses VP28 at an early stage of infection in insect cells. Baculovirus expressed rVP28 was able to maintain its structural and antigenic conformity as indicated by immunofluorescence assay and western blot analysis. Interestingly, our results with confocal microscopy revealed that rVP28 was able to localize on the plasma membrane of insect cells infected with recombinant baculovirus. In addition, we demonstrated with transmission electron microscopy that baculovirus successfully acquired rVP28 from the insect cell membrane via the budding process. Using this baculovirus displaying VP28 as a vaccine against WSSV, we observed a significantly higher survival rate of 86.3% and 73.5% of WSSV-infected shrimp at 3 and 15 days post vaccination respectively. Quantitative real-time PCR also indicated that the WSSV viral load in vaccinated shrimp was significantly reduced at 7 days post challenge. Furthermore, our RT-PCR and immunohistochemistry results demonstrated that the recombinant baculovirus was able to express VP28 in vivo in shrimp tissues. This study will be of considerable significance in elucidating the morphogenesis of WSSV and will pave the way for new generation vaccines against WSSV.     

Fluorescence spectra of blood components for breast cancer diagnosis

OBJECTIVE: To explore whether fluorescence emission spectroscopy of blood components can differentiate normal from early and advanced stages of breast cancer using stepwise discriminant analysis. MATERIALS AND METHODS: Fluorescence emission spectra were measured for blood components of three different groups: 35 normal controls, 28 with early-stage, and 18 with advanced-stage breast cancer. The data from the spectra were subjected to Fisher's linear discriminant analysis. Classification accuracy, specificity, and sensitivity of the technique were calculated for breast cancer diagnosis. RESULTS: Fluorescence emission spectra of blood components accurately distinguished normal from early-stage and advanced-stage breast cancer in 91.4% of original cases and 90.1% for cross-validated cases. The sensitivity and specificity were 80.4% and 100%, respectively, in distinguishing subjects with breast cancer from normal controls. CONCLUSION: Our statistical evaluation indicates that porphyrin in blood can be used as a reliable tumor marker. Fluorescence emission spectroscopy of blood components and statistical evaluations should be further investigated for a variety of tumors.     

Stabilization of glomerular filtration rate in advanced chronic kidney disease: a two-year follow-up of a cohort of chronic kidney disease patients stages 4 and 5

This study examines whether stabilization of the glomerular filtration rate (GFR) is possible in patients with advanced chronic kidney disease (CKD), managed in a CKD clinic. A cohort of 82 patients with stages 4 and 5 CKD was followed for a period of 2 years after initiation of erythropoietin for anemia to determine the GFR and the frequency of primary outcomes (dialysis, transplantation, or death). GFR, calculated by the abbreviated Modification of Diet in Renal Disease formula, was determined every 3 months. After 24 months, 35 subjects (43%) developed a primary outcome. Controlled for other risk factors, the risk of having a primary outcome increased 19.7% for every unit that the GFR decreased (95% confidence interval [CI], 11.9%-26.8%, P < .001) and decreased 21.7% for every unit that the hemoglobin increased (95% CI, 0.5%-38.4%, P < .001). Blacks had a 3.1 times higher risk (95% CI, 1.4-6.9, P = .006) of developing a primary outcome than other ethnicities. In subjects who did not develop primary outcomes (n = 47 or 57%), GFR remained unchanged (19.5 +/- 9.1 at the end of the study v 20.8 +/- 5.3 mL/min/1.73 m(2) at baseline, P = .16). The standardized mortality rate was 4.75 and 9.77 per 100 person-year for stages 4 and 5, respectively. We conclude that stabilization of GFR over a 2-year period can be achieved in many patients with advanced CKD treated with erythropoietin in a CKD clinic. Although the precise reason for the stabilization of GFR cannot be elucidated from this study, our data are "proof of concept" that CKD outcomes can be improved in a CKD clinic setting.     

A method for measuring the cross sectional area of the anterior portion of the optic nerve in vivo using a fast 3D MRI sequence

Purpose:

To investigate the three‐dimensional (3D) fast‐recovery fast spin‐echo accelerated (FRFSE‐XL) sequence as a new application for measuring the intraorbital optic nerve (ION) mean cross‐sectional area in vivo and to determine its value within a commonly used high resolution imaging protocol.

Materials and Methods:

The entire ION was scanned in nine healthy volunteers (mean age 32 ± 4 years) using the 3D FRFSE‐XL sequence and a commonly used high resolution short‐echo fast fluid‐attenuated inversion‐recovery (sTE fFLAIR) sequence with identical slice locations at 1.5T. The mean cross‐sectional area from both sequences was measured on a slice‐by‐slice basis from 3 mm behind the globe to the orbital apex. The reproducibility of both techniques was assessed from repeated scans (scan‐rescan) and repeated image analysis (intraobserver).

Results:

Measurement of the mean cross‐sectional area of the anterior 9 mm segment of the ION was only possible using the 3D FRFSE‐XL sequence with a mean area of 11.6 ± 2.2 mm² (scan rescan COV = 3.3 ± 1.5, intraobserver COV = 2.4 ± 0.02) whereas the remainder segment of the ION (i.e., 9 mm behind the globe to the orbital apex) could only be measured with the use of the sTE fFLAIR with a mean area of 8.5 ± 1.7 mm² (scan rescan COV = 4.9 ± 2.5 and intraobserver COV = 3.70 ± 0.03).

Conclusion:

The 3D FRFSE‐XL allows fast and reproducible measurement of the cross‐sectional area of the anterior 9mm segment of the ION, which is not possible using commonly used imaging sequences due to image degradation from motion, and is of complementary value to the existing imaging protocol for ION atrophy quantification. J. Magn. Reson. Imaging 2010;31:1486–1491. © 2010 Wiley‐Liss, Inc.