Aging is an organ-specific process: changes in homeostasis of iron and redox proteins in the rat

Organ-specific changes of iron- and redox-related proteins occur with age in the rat. Ferritin, the major iron storage and detoxifying protein, as well as the proteins of the methionine-centered redox cycle (MCRC) were examined in old and young animals, and showed organ-dependent changes. In spleens and livers of aged rats, ferritin (protein) levels were greater than in young ones, and their iron saturation increased, rendering higher ferritin-bound iron (FtBI). Iron saturation of the ferritin molecule in the tongues and sternohyoids of old rats was lower but ferritin level was higher than in young rats, resulting in increased FtBI with age. Ferritin level in the esophagus of older rats was lower than in young rats but its molecular iron content higher thus the total FtBI remained the same. In the larynx, both ferritin and its iron content were the same in young and old animals. MCRC proteins were measured in livers and spleens only. With aging, methionine sulfoxide reductase A and B (MsrA and MsrB) levels in livers and spleens decreased. Thioredoxin1 (Trx) and Trx-reductase1 were elevated in old spleens, but reduced in livers. Aged spleens showed reduced Msr isozyme activity; but in the liver, its activity increased. mRNA changes with age were monitored and found to be organ specific. These organ-specific changes could reflect the different challenges and the selective pathways of each organ and its resultant capacity to cope with aging.     

The increased risk for pneumocystis pneumonia in patients receiving rituximab-CHOP-14 can be prevented by the administration of trimethoprim/sulfamethoxazole: a single-center experience

Recent studies suggest an increased risk for Pneumocystis jirovecii pneumonia (PJP) in adults receiving short-interval rituximab-CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) therapy for diffuse large cell B cell lymphoma (DLBCL). This retrospective study evaluates precise PJP incidence and the efficacy of anti-PJP prophylaxis in DLBCL. Patients with DLBCL, aged ≥18 years and treated between December 2004 and December 2010, were included. Details of treatment-related respiratory infections, focusing on PJP incidence, risk factors and prophylaxis, were assessed. A total of 132 patients were analyzed; 47 were treated with rituximab-CHOP therapy every 21 days (R-CHOP-21) and 85 were treated every 14 days (R-CHOP-14). The incidence of treatment-related respiratory infections was higher in patients receiving R-CHOP-14. PJP was diagnosed in 5 patients: 4 in the R-CHOP-14 (6.6%) and 1 in the R-CHOP-21 cohort (2.6%), using triplex polymerase chain reaction (PCR) for PJ in bronchoalveolar fluid. None of the patients receiving P.jirovecii prophylaxis (n = 33) developed PJP, compared with 6.6% of those treated with R-CHOP-14 without such prophylaxis. An older age and R-CHOP administered every 14 rather than every 21 days increased the PJP risk. Trimethoprim/sulfamethoxazole prophylaxis is found to be highly efficient in preventing this life-threatening complication and, therefore, should be recommended for patients receiving the R-CHOP-14 regimen.     

Preliminary prospective explanatory observation on the impact of 3-month steroid therapy on the objective measures of sleep-disordered breathing

Background  

Excess endogenous steroids are a risk factor for obstructive sleep apnea (OSA). The role of exogenous steroids in this setup is not known. In this study, we prospectively looked at the consequences of a 3-month steroid treatment on the objective measures of sleep-disordered breathing.     

Natural History After Acute Necrotizing Pancreatitis: a Large US Tertiary Care Experience

Background

Most studies of acute necrotizing pancreatitis (ANP) focus on short-term outcomes. We evaluated long-term survival and outcomes following ANP.

Methods

Patients treated for ANP at the University of Pittsburgh Medical Center from 2001 to 2008 were studied. Data on presentation and course during initial hospitalization and follow-up (median 34 months) was extracted.

Results

Mean age of patients (n?=?167) was 53?±?16 years; 70 % were male, 94 % white, 71 % transfers, 52 % biliary etiology, and 78 % had first-attack of acute pancreatitis. Majority had severe disease with high Acute Physiology and Chronic Health Evaluation II (APACHE-II) score (median 11), length of stay (median 26 days), intensive care unit (ICU) admission (87 %), presence of systemic inflammatory response syndrome (SIRS) (90 %), persistent organ failure (60 %), and infected necrosis (50 %). Intervention was needed in 74 %. Eighteen (10.8 %) patients died during index hospitalization, 9 (5.4 %) during the first year, and 13 (7.8 %) after 1 year. Median survival was significantly shorter when compared with age- and sex-matched US general population (9.1 vs. 26.1 years, p?<?0.001). Increasing age (HR 1.05), persistent organ failure (HR 4.5), and >50 % necrosis (HR 3.8) were independent predictors of death at 1 year. In eligible patients, new-onset diabetes, oral pancreatic enzyme replacement therapy, and disability were noted in 45, 25, and 53 %, respectively.

Conclusion

ANP significantly impacts long-term survival. A high proportion of patients develop functional derangement and disability following ANP.

     

Pulmonary hypertension in patients with end-stage renal disease

BACKGROUND: The aims of this study were to evaluate the incidence of unexplained pulmonary hypertension (PH) among patients with end-stage renal disease (ESRD) and to suggest possible etiologic factors. METHODS: The incidence of PH was prospectively estimated by Doppler echocardiography in 58 patients with ESRD receiving long-term hemodialysis via arteriovenous access, and in control groups of 5 patients receiving peritoneal dialysis (PD) and 12 predialysis patients without a known other cause to suggest the presence of PH. Clinical variables were compared between patients with and without PH receiving hemodialysis. Changes in pulmonary artery pressure (PAP) values before and after onset of hemodialysis via arteriovenous access, arteriovenous access compression, and successful kidney transplantation were recorded. RESULTS: PH > 35 mm Hg was found in 39.7% of patients receiving hemodialysis (mean +/- SD, 44 +/- 7 mm Hg; range, 37 to 65 mm Hg), in none of the patients receiving PD, and in 1 of 12 predialysis patients. Patients with PH receiving hemodialysis had a significantly higher cardiac output (6.9 L/min vs 5.5 L/min, p = 0.017). PH developed in four of six patients with normal PAP after onset of hemodialysis therapy via arteriovenous access. One-minute arteriovenous access compression in four patients decreased the mean systolic PAP from 52 +/- 7 to 41 +/- 4 mm Hg (p = 0.024). PH normalized in four of five patients receiving hemodialysis following kidney transplantation. Kaplan-Meier survival analysis according to PAP values revealed significant survival differences (p < 0.024). CONCLUSIONS: This study demonstrates a surprisingly high incidence of PH among patients with ESRD receiving long-term hemodialysis with surgical arteriovenous access. Both ESRD and long-term hemodialysis via arteriovenous access may be involved in the pathogenesis of PH by affecting pulmonary vascular resistance and cardiac output.