Renal calcium, phosphorus, magnesium and uric acid handling: comparison between stage III chronic kidney disease patients and healthy oldest old

Introduction

It is known that chronic kidney disease (CKD) and senescence bring about a progressive reduction in glomerular filtration rate (GFR) and that in the former this is usually associated with an increase in the fractional excretion of calcium, phosphorus, magnesium, and uric acid. However, it has not yet been explained how these substances are excreted in the healthy oldest old. Thus, in the present study, we examined the renal handling of these substances in very aged people in comparison with CKD patients with similar GFR levels (stage III??CKD).

Materials and methods

Twenty volunteers were studied; 10 of them were healthy very old (VO) (??75?years old) individuals and 10 were stage III CKD patients. Exclusion criteria were as follows: presence of altered (abnormally high or low) plasma calcium, phosphorus, magnesium and uric acid, as well as previous diagnoses of diabetes mellitus and obstructive uropathy and use of drugs that could alter plasma levels of the studied substances. All volunteers were on a diet with the same content of these elements (3-day dietary register). We measured calcium, phosphorus, magnesium, uric acid, creatinine in serum plasma and morning urine, as well as serum parathyroid hormone level, in each volunteer. From these data, fractional excretion (FE) of these substances was obtained. A statistical analysis was carried out using the Wilcoxon test.

Results

Serum creatinine: 1.8?±?0.4?mg/dl (CKD) versus 0.8?±?0.2?mg/dl (VO), p?=?0.0002; serum calcium: 9.1?±?0.3?mg/dl (CKD) versus 8.7?±?0.4 (VO), p?=?0.022; serum magnesium: 2.3?±?0.2?mg/dl (CKD) versus 2.0?±?0.1 (VO), p?=?0.05; serum phosphorus: 3.9?±?0.5?mg/dl (CKD) versus 3.0?±?0.4?mg/dl (VO), p?=?0.002; serum uric acid: 6.6?±?1.5 (CKD) versus 5.2?±?1.4?mg/dl (VO), p?=?0.04; FE of calcium: 2.5?±?1?% (CKD) versus 0.8?±?0.3?% (VO), p?=?0.04; FE of magnesium: 7.2?±?4.1?% (CKD) versus 2.9?±?0.9?% (VO), p?=?0.02; FE of phosphorus: 25?±?9?% (CKD) versus 9.1?±?5.7(VO), p?=?0.001; FE of uric acid: 10?±?3?% (CKD) versus 8?±?5?% (VO), p?=?0.05.

Conclusion

Serum levels and FE of calcium, phosphorus, magnesium and uric acid were significantly higher in CKD patients compared to healthy very old people with similar GFR, except for serum magnesium and FE of uric acid, which were similar in both groups.     

Do plastics serve as a possible vector for the spread of antibiotic resistance? First insights from bacteria associated to a polystyrene piece from King George Island (Antarctica)

The retrieval of a polystyrene macro-plastic piece stranded on the shores in King George Island (South Shetlands, Antarctica) gave the opportunity to explore the associated bacterial flora. A total of 27 bacterial isolates were identified by molecular 16s rRNA gene sequencing and 7 strains were selected and screened for their ability to produce biofilm and antibiotic susceptibility profiles. All the bacterial isolates were able to produce biofilm. The Kirby-Bauer disk diffusion susceptibility test to 34 antibiotics showed multiple antibiotic resistances against the molecules cefuroxime and cefazolin (belonging to cephalosporins), cinoxacin (belonging to quinolones) and ampicillin, amoxicillin + clavulanic acid, carbenicillin and mezlocillin (belonging to beta-lactams). The obtained results suggest that plastics can serve as vectors for the spread of multiple resistances to antibiotics across Antarctic marine environments and underline the relevance of future studies on this topic.     

The Association Between Neighborhood Social Vulnerability and COVID-19 Testing,Positivity, and Incidence in Alabama and Louisiana

Racial/ethnic and socioeconomic disparities in COVID-19 burden have been widely reported. Using data from the state health departments of Alabama and Louisiana aggregated to residential Census tracts, we assessed the relationship between social vulnerability and COVID-19 testing rates, test positivity, and incidence. Data were cumulative for the period of February 27, 2020 to October 7, 2020. We estimated the association of the 2018 Social Vulnerability Index (SVI) overall score and theme scores with COVID-19 tests, test positivity, and cases using multivariable negative binomial regressions. We adjusted for rurality with 2010 Rural–Urban Commuting Area codes. Regional effects were modeled as fixed effects of counties/parishes and state health department regions. The analytical sample included 1160 Alabama and 1105 Louisiana Census tracts. In both states, overall social vulnerability and vulnerability themes were significantly associated with increased COVID-19 case rates (RR 1.57, 95% CI 1.45–1.70 for Alabama; RR 1.36, 95% CI 1.26–1.46 for Louisiana). There was increased COVID-19 testing with higher overall vulnerability in Louisiana (RR 1.26, 95% CI 1.14–1.38), but not in Alabama (RR 0.95, 95% CI 0.89–1.02). Consequently, test positivity in Alabama was significantly associated with social vulnerability (RR 1.66, 95% CI 1.57–1.75), whereas no such relationship was observed in Louisiana (RR 1.05, 95% CI 0.98–1.12). Social vulnerability is a risk factor for COVID-19 infection, particularly among racial/ethnic minorities and those in disadvantaged housing conditions without transportation. Increased testing targeted to vulnerable communities may contribute to reduction in test positivity and overall COVID-19 disparities.

     

Hepatocyte lesions and cellular immune response in yellow fever infection

The study of the in-situ cellular immune response is very important for the understanding of different liver infections. In the present study, 53 liver samples obtained by viscerotomy from patients who died during the course of jungle yellow fever were analyzed. The diagnosis was confirmed by serology, viral isolation and virus-specific immunohistochemistry. The specimens were analyzed by immunohistochemistry using specific antibodies for apoptosis, CD45RO, CD4, CD8, CD20, S100, CD57 and CD68. Quantitative analysis of the labeling pattern showed a clear predominance of the different phenotypes in the portal tract and midzone region of the acini. There was a predominance of T CD4+ lymphocytes, accompanied by the presence of T CD8+ lymphocytes, natural killer cells (CD57), macrophages and antigen-presenting cells (S100). The disproportion between the intensity of inflammation and the degree of hepatic injury was probably due to the intense apoptotic component, which classically does not induce an inflammatory response. The present study demonstrates that, despite the disproportion between injury and inflammation, the cellular immune response plays an important role in the pathogenesis of the hepatocytic injury observed in yellow fever, probably as a result of cytolytic actions through mechanisms involving MHC II and the activation of Fas receptors and granzymes/perforins.     

Pneumonia case-finding in the RESPIRE Guatemala indoor air pollution trial: standardizing methods for resource-poor settings

OBJECTIVE: Trials of environmental risk factors and acute lower respiratory infections (ALRI) face a double challenge: implementing sufficiently sensitive and specific outcome assessments, and blinding. We evaluate methods used in the first randomized exposure study of pollution indoors and respiratory effects (RESPIRE): a controlled trial testing the impact of reduced indoor air pollution on ALRI, conducted among children 90% of children meeting ALRI criteria, of whom about 70% attended a physician. Referrals for cough without respiratory signs and self-referrals contributed 19.0% and 17.9% of physician-diagnosed ALRI cases respectively. Intervention group attendance following ALRI referral was 7% higher than controls, a trend also seen in compliance with RSV tests and CXR. There was no evidence of bias by intervention status in fieldworker classification or physician diagnosis. Incidence of fieldworker ALRI (1.12 episodes/child/year) is consistent with high sensitivity and low specificity; incidence of physician-diagnosed ALRI (0.44 episodes/child/year) is consistent with comparable studies. CONCLUSION: The combination of case-finding methods achieved good sensitivity and specificity, but intervention cases had greater likelihood of reaching the physician and being investigated. There was no evidence of bias in fieldworkers classifications despite lack of concealment at home visits. Pulse oximetry offers practical, objective severity assessment for field studies of ALRI.     

Chagas disease in rural areas of Chaco Province, Argentina: epidemiologic survey in humans, reservoirs, and vectors

We studied the seroprevalence of antibodies against Trypanosoma cruzi in the human population along with domiciliary infestation by triatomine bugs in an area endemic for Chagas disease in the Chaco Province of Argentina. In addition, we carried out parasitologic surveys in patients, dogs, wild mammals, and vectors. The mean seroprevalence in humans was 27.81% (109 of 392) and 24.14% (63 of 261) in 1-15-year-old children. The minimum domiciliary infestation rate was 13.33%, with certain areas reaching 53.85%. The prevalence was 15.09% (16 of 106) in dogs and 35.71% (10 of 28) in opossums. Infection with T. cruzi was detected in 30.10% (59 of 196) of the Triatoma infestans tested. Compared with nationwide studies, our data suggest that 1) there are zones requiring immediate sanitary action, and 2) nationwide estimates are based on very heterogeneous epidemiologic situations. This heterogeneity emphasizes the importance of in-depth studies of restricted areas to provide additional information for a better understanding of the present status of Chagas disease in Argentina.     

Right hepatic artery indwelling catheter for adjuvant chemotherapy after right hepatectomy

Intraarterial hepatic adjuvant chemotherapy after radical hepatic resection for liver metastases from colorectal carcinoma lowers the rate of liver disease relapse. The technique for catheter implantation in the right hepatic artery for subsequent intraarterial hepatic adjuvant chemotherapy after right hepatectomy is herein described and recommended as an effective alternative approach to the standard catheter implantation in the gastroduodenal artery in cases of hepatectomies for liver metastases from colorectal cancer.     

Functional assessment of neuronal cannabinoid receptors in the muscular layers of human ileum and colon

BACKGROUND & AIMS: The notion that specific receptors account for the ability of natural and synthetic cannabinoids to alter physiological functions, prompted this study aimed at assessing their functional presence in the human gut. METHODS: The effects have been studied of cannabinoids and selective antagonists of their receptors on chemically or electrically evoked contractions in preparations of human intestinal smooth muscle in vitro. RESULTS: Atropine prevented the contractions of longitudinal and circular muscle strips of ileum and colon induced by carbachol or electrical field stimulation; tetrodotoxin abolished only the latter which suggests they do involve activation of cholinergic neurons. The synthetic cannabinoid (+)WIN 55,212-2 had no effect on carbachol contractions, but in a concentration-dependent fashion prevented those elicited by electrical field stimulation - which were insensitive to the putative endogenous cannabinoid anandamide - more potently in longitudinal than in circular strips. The selective CB1 receptor antagonist SR141716, which had no effect in the absence of (+)WIN 55,212-2, competitively antagonised its inhibition of electrical field stimulation contractions, unlike the selective CB2 antagonist SR144528. CONCLUSIONS: Cannabinoid CB1 receptors are functionally present in the human ileum and colon; their pharmacological activation apparently results in inhibition of excitatory cholinergic pathways subserving smooth muscle contraction.     

Management of Pain and Nausea in Outpatient Surgery

The cost associated with surgical procedures has been dramatically decreased by the ability to perform these procedures on an outpatient basis. Pain and nausea, two common symptoms after anesthesia and surgical procedures, are among the greatest concerns for patients and their family members. As a result of the distress and sequelae associated with these symptoms, clinicians have attempted to determine the optimal intraoperative and postoperative symptom management for patients. The purpose of this quality improvement project was to describe the incidence of these symptoms and their management in patients who underwent planned outpatient surgical procedures in a cancer center. A sample of 39 patients were accrued at a comprehensive cancer center over a 3-month period. Data were collected at three specific time points (i.e., preoperatively, at 24 hours and at 7 days postoperatively). Postoperative pain and nausea were generally well managed, but improvement was needed in preoperative patient teaching, including the topics of drug and nondrug interventions. The methods used in this project have potential application for the measurement of other clinical outcomes after outpatient surgical procedures.