Identification of species belonging to the Bifidobacterium genus by PCR-RFLP analysis of a hsp60 gene fragment

Abstract BACKGROUND: Bifidobacterium represents one of the largest genus within the Actinobacteria, and includes at present 32 species. These species share a high sequence homology of 16S rDNA and several molecular techniques already applied to discriminate among them give ambiguous results.The slightly higher variability of the hsp60 gene sequences with respect to the 16S rRNA sequences offers better opportunities to design or develop molecular assays, allowing identification and differentiation of closely related species. hsp60 can be considered an excellent additional marker for inferring the taxonomy of the members of Bifidobacterium genus. RESULTS: This work illustrates a simple and cheap molecular tool for the identification of Bifidobacterium species. The hsp60 universal primers were used in a simple PCR procedure for the direct amplification of 590 bp of the hsp60 sequence. The in silico restriction analysis of bifidobacterial hsp60 partial sequences allowed the identification of a single endonuclease (HaeIII) able to provide different PCR-restriction fragment length polymorphism (RFLP) patterns in the Bifidobacterium spp. type strains evaluated. The electrophoretic analyses allowed to confirm the different RFLP patterns. CONCLUSIONS: The developed PCR-RFLP technique resulted in efficient discrimination of the tested species and subspecies and allowed the construction of a dichotomous key in order to differentiate the most widely distributed Bifidobacterium species as well as the subspecies belonging to B. pseudolongum and B. animalis

END-DIALYSIS OVERWEIGHT AND CHRONIC INFLAMMATION. A DANGEROUS CONNECTION

INTRODUCTION AND AIMS: Attaining dry body weight is paramount in dialysis practice, but this goal is not always reached. We hypothesized that the amount of enddialysis overweight (edOW), could be associated to increased chronic inflammation and mortality. Aim of the study: to evaluate the effect of edOW on serum C-reattive protein(hsCRP) concentrations and on survival in a cohort of 182 prevalent HD patients (pts) followed for 36 months. METHODS: In 182 pts (117 men, age 65612 years, vintage 48 months; range 6-336), edOW was present in 98/182 (54%) pts. Mean value was 0.460.2 Kg (range: 0.1-1.4). In the 98 pts with edOW (Group 1) and in the other 84 (Group 2) we evaluated: Ultrafiltration rate(UFR), hsCRPdry body weight (dBW), Kt/V, protein catabolic rate (PCRn), interdialytic weight gain (IDWG), mean arterial pressure (MAP). Unpaired Student’s t test was employed to compare groups, linear regression analysis to test correlations, log-rank test and Kaplan-Meier curves to evaluate survival. RESULTS: Mean UFR was 11.762.8 ml/Kg/hour, dBW 64612 Kg, hsCRP 6.6 (0.2-36) mg/L, Kt/V 1.2760.09, PCRn 1.0660.10 g/Kg/day, IDWG 2.860.4 Kg, MAP 9766.5 mmHg. edOW and hsCRP were directly and significantly correlated (r= 0.67; p<0.0001). Comparison between pts with (Group 1) and without (Group 2) edOW showed significant differences in: UFR (12.762.6 vs 10.962.6 ml/Kg/hour; p< 0.0001), hsCRP (13.068.1 vs 5.265.3 mg/L; p< 0.0001), and PCRn (1.0360.09 vs 1.0860.10 g/Kg/day; p<0.004). 98 pts (54%) died during follow-up for cardiovascular complications in 69% of cases. Survival curves showed significantly greater mortality in Group 1 vs Group 2 in relation to the amount of edOW, and hsCRP (p<0.0001). CONCLUSIONS: : edOW and chronic inflammation are directly correlated in HD pts, and both are associated to a greater long-term risk of mortality

CHRONIC INFLAMMATION AND END-DIALYSIS OVERWEIGHT. A 36 MONTH PROSPECTIVE OBSERVATIONAL STUDY

Introduction and Aims: Attaining dry body weight is paramount in dialysis practice, but this goal is not always reached.We hypothesized that the amount of end-dialysis overweight (edOW), could be associated to increased chronic inflammation and mortality. Aim of the study: to evaluate the effect of edOWon serum C-reattive protein (hsCRP) concentrations and on survival in a cohort of 182 prevalent HD patients ( pts) followed for 36 months. Methods: In 182 pts (117 men, age 65±12 years, vintage 48 months; range 6-336), edOWwas present in 98/182 (54%) pts. Mean value was 0.4±0.2 Kg (range: 0.1-1.4). In the 98 pts with edOW(Group 1) and in the other 84 (Group 2) we evaluated: Ultrafiltration rate(UFR), hsCRPdry body weight (dBW), Kt/V, protein catabolic rate (PCRn), interdialytic weight gain (IDWG), mean arterial pressure (MAP). Unpaired Student’s t test was employed to compare groups, linear regression analysis to test correlations, log-rank test and Kaplan-Meier curves to evaluate survival. Results: Mean UFR was 11.7±2.8 ml/Kg/hour, dBW 64±12 Kg, hsCRP 6.6 (0.2-36) mg/L, Kt/V 1.27±0.09, PCRn 1.06±0.10 g/Kg/day, IDWG 2.8±0.4 Kg, MAP 97±6.5 mmHg. edOWand hsCRP were directly and significantly correlated (r= 0.67; p<0.0001). Comparison between pts with (Group 1) and without (Group 2) edOW showed significant differences in: UFR (12.7±2.6 vs 10.9±2.6 ml/Kg/hour; p< 0.0001), hsCRP (13.0±8.1 vs 5.2±5.3 mg/L; p< 0.0001), and PCRn (1.03±0.09 vs 1.08±0.10 g/Kg/day; p<0.004). 98 pts (54%) died during follow-up for cardiovascular complications in 69% of cases. Survival curves showed significantly greater mortality in Group 1 vs Group 2 in relation to the amount of edOW, and hsCRP (p<0.0001). Conclusions: edOWand chronic inflammation are directly correlated in HD pts, and both are associated to a greater long-term risk of mortality

Use of renin-angiotensin system blockers increases serum potassium in anuric hemodialysis patients.

Angiotensin converting enzyme inhibitors (ACEi) and angiotensin receptor blockers (ARB) are increasingly used in uremic patients (pts). However, their effect on serum potassium (sK) concentrations in anuric pts on chronic hemodialysis treatment (HD) is controversial. The aim of the study was to evaluate sK before and after the start of ACEi/ARB therapy. In the period 1/1/2015 - 31/12/2015, 112 out of 240 prevalent HD pts on thrice weekly HD treatment followed at our institution started the ACEi/ARB therapy. The mean age was 67 ± 14 years, 67/112 were men, dialysis vintage was 6-212 months. In the 3 months before (PRE; N° 36 HD sessions) and after (POST; N° 36 HD sessions) the start of ACEi/ARB therapy, the following variables were evaluated in pre dialysis after the long interdialysis interval: sK (mean of 12 determinations; mmol/L), maximum sK (maximum K value observed during observations; sKmax; mmol/L), serum sodium (sNa; mmol/L), pre dialysis systolic blood pressure (SBP; mm Hg) and diastolic blood pressure (DBP; mm Hg), body weight (BW; Kg), interdialytic weight gain (IWG; Kg), Kt/V, serum bicarbonate concentrations (sBic; mmol/L), protein catabolic rate (PCRn; g/KgBW/day). SBP, DBP, IWG are the mean of the 24 HD sessions. Out of 112 patients, 102 were on antihypertensive therapy. The duration of HD and blood and dialysate flow rates were kept constant. Data are expressed as mean ± SD. Student t test for paired and unpaired data for normally distributed variables, Mann-Whitney test for medians, χ2 test for categorical data were employed to compare groups. A significant difference was defined as p < 0.05. sK increased from 5.0 ± 0.4 mmol/L PRE to 5.7 ± 0.5 mmol/L POST (p < 0.0001). sKmax increased from 5.3 ± 0.5 mmol/L PRE to 6.2 ± 0.6 mmol/L POST (p < 0.0001). The percentage of pts with normal sK concentrations decreased from 82% PRE to 29% POST (p < 0.0001). Mild hyperkalemia increased from 18 to 52% (p < 0.001); in 31% of the patients, it was necessary to reduce the K dialysate concentration. None of the patients had severe hyperkalemia PRE, but 19% developed severe hyperkalemia POST (p < 0.0001) necessitating treatment withdrawal. Mean sK in these pts varied from 5.2 ± 0.3 mmol/L PRE to 6.5 ± 0.2 mmol/L at the moment of withdrawal (p < 0.0001) and sKmax from 5.5 ± mmol/L PRE to 6.9 ± 0.3 mmol/L (p< 0.0001). After withdrawal of ACEi/ARB, sK and sKmax concentrations decreased to basal levels within 1 month. There were no significant changes of BW, IWG, SBP, DBP, Na, Hb, Kt/V, sBic, and PCRn in both periods. ACEi/ARB therapy is associated with an increased risk of hyperkalemia in anuric hemodialysis patients. The proportion of patients with normal sK concentrations decreased from 82 to 29% and with mild hyperkalemia increased from 18 to 52%. Severe hyperkalemia necessitating the interruption of ACEi/ARB therapy developed in 19% of patients. This suggests great caution in the widest utilization of this class of drugs in HD patients

Probiotici e prebiotici nell\u2019alimentazione animale

L\u2019incidenza delle malattie trasmesse da alimenti di origine animale \ue8 in costante ascesa in tutti i Paesi industrializzati; si crea, perci\uf2, la necessit\ue0 di attuare misure di controllo sempre pi\uf9 restrittive negli allevamenti, soprattutto a seguito del divieto sull\u2019uso degli antibiotici come promotori della crescita a scopo sub-terapeutico. I principali patogeni che si ritrovano nei prodotti di origine animale, a volte veicolati nel tratto gastrointestinale degli animali in maniera asintomatica, sono: Campylobacter jejuni, Clostridium perfringens, E. coli 0157:H7, Listeria monocytogenes, Salmonella, Staphylococcus aureus. \uc8 necessario trovare, velocemente, soluzioni alternative per controllare e prevenire la diffusione dei patogeni enterici, al fine di ridurre la loro presenza nel prodotto finito e limitare la minaccia per la salute dell\u2019uomo. La modulazione del tratto gastrointestinale, attraverso l\u2019utilizzo di additivi alimentari come probiotici e prebiotici, offre una valida soluzione per mantenere gli animali in salute, ridurre il rischio di contrarre malattie gastrointestinali e migliorare la qualit\ue0 delle carni destinate al consumo umano. In questo articolo verranno discusse le pi\uf9 recenti applicazioni di probiotici e prebiotici in campo animale, volte alla riduzione della presenza di microrganismi patogeni, potenziali cause di intossicazioni alimentari, nelle carni

Total Convection Affects Serum β2 Microglobulin and C-Reactive Protein but Not Erythropoietin Requirement following Post-Dilutional Hemodiafiltration

BACKGROUND: Inflammation and increased erythropoiesis stimulating agents (ESA) requirement are frequently associated in patients on dialysis. On-line hemodiafiltration (ol-HDF), putting together high levels of diffusion, and convection could improve both conditions. However, it is still not known which depurative component plays a major role in determining this result. The aim of the study was to evaluate the role of convection and diffusion on long-term variations of serum β2 microglobulin (Δβ2M), high-sensitive C-reactive protein (ΔhsCRP) concentrations, and ESA requirement (ΔESA) in ol-HDF. METHODS: Seventy-three patients prevalent on high flux HD (hfHD) were studied. Thirty-eight patients were switched from hfHD to post-dilutional ol-HDF (Study group); the other 35 patients were considered the Control group. At 6 and 12 months, the effects of ol-HDF and hfHD on ΔhsCRP, ΔB2M, and ΔESA (U/kg/week) were evaluated. Other variables considered were body weight (BW), serum albumin (sAlb), hemoglobin (Hb), and equilibrated Kt/V (eKt/V). Iron therapy and ESA were administered intravenously according to the K/DOQI guidelines in order to maintain transferrin saturation between 20 and 40%, serum ferritin between 150 and 500 ng/ml and Hb between 11 and 12 g/dl. Qb, treatment time and Qd remained constant. Ol-HDF and hfHD were performed using membranes of size 1.9-2.1 sqm. Ultrapure dialysate and substitution fluid were employed in both HDF and HD treatments. Data are expressed as mean ± SD. Paired t test, Mann-Whitney U test, and simple and multiple regression analyses were employed for statistical evaluation. RESULTS: STUDY GROUP: total convective volume (TCV) was 22.1 ± 1.9 l/session. A significant reduction of hsCRP: from 6.8 ± 7.1 to 2.3 ± 2.4 mg/dl (p < 0.001), β2M: from 36.5 ± 14.4 to 24.7 ± 8.6 mg/dl (p < 0.0001) and ESAdose: from 107 ± 67 to 65 ± 44 U/kg/week (p < 0.005) was observed. No significant variations of Hb, BW and sAlb were seen. A significant inverse correlation was found between TCV and Δβ2M (r = -0.627; p < 0.0001), and TCV and ΔhsCRP (r = -0.514; p < 0.0001); no correlation between TCV and ΔESAdose was observed. No correlation was found between eKt/V and Δβ2M, ΔhsCRP, and ΔESAdose. Multiple regression analysis with ΔESAdose as dependent variable showed ΔhsCRP as the only significantly associated independent factor (p < 0.01). CONTROL GROUP: no significant variations of hsCRP, β2M, and ESAdose were observed over time. CONCLUSIONS: Ol-HDF induces a long-term significant reduction in pre-dialysis β2M and hsCRP concentrations. The magnitude of reduction is directly correlated to the amount of TCV achieved but not on eKt/V. The observed reduction in ESAdose requirement is independent either on convection or diffusion, but is directly associated to the concomitant reduction of inflammation

Total Convection Affects Serum β2 Microglobulin and C-Reactive Protein but Not Erythropoietin Requirement following Post-Dilutional Hemodiafiltration

BACKGROUND: Inflammation and increased erythropoiesis stimulating agents (ESA) requirement are frequently associated in patients on dialysis. On-line hemodiafiltration (ol-HDF), putting together high levels of diffusion, and convection could improve both conditions. However, it is still not known which depurative component plays a major role in determining this result. The aim of the study was to evaluate the role of convection and diffusion on long-term variations of serum β2 microglobulin (Δβ2M), high-sensitive C-reactive protein (ΔhsCRP) concentrations, and ESA requirement (ΔESA) in ol-HDF. METHODS: Seventy-three patients prevalent on high flux HD (hfHD) were studied. Thirty-eight patients were switched from hfHD to post-dilutional ol-HDF (Study group); the other 35 patients were considered the Control group. At 6 and 12 months, the effects of ol-HDF and hfHD on ΔhsCRP, ΔB2M, and ΔESA (U/kg/week) were evaluated. Other variables considered were body weight (BW), serum albumin (sAlb), hemoglobin (Hb), and equilibrated Kt/V (eKt/V). Iron therapy and ESA were administered intravenously according to the K/DOQI guidelines in order to maintain transferrin saturation between 20 and 40%, serum ferritin between 150 and 500 ng/ml and Hb between 11 and 12 g/dl. Qb, treatment time and Qd remained constant. Ol-HDF and hfHD were performed using membranes of size 1.9-2.1 sqm. Ultrapure dialysate and substitution fluid were employed in both HDF and HD treatments. Data are expressed as mean ± SD. Paired t test, Mann-Whitney U test, and simple and multiple regression analyses were employed for statistical evaluation. RESULTS: STUDY GROUP: total convective volume (TCV) was 22.1 ± 1.9 l/session. A significant reduction of hsCRP: from 6.8 ± 7.1 to 2.3 ± 2.4 mg/dl (p < 0.001), β2M: from 36.5 ± 14.4 to 24.7 ± 8.6 mg/dl (p < 0.0001) and ESAdose: from 107 ± 67 to 65 ± 44 U/kg/week (p < 0.005) was observed. No significant variations of Hb, BW and sAlb were seen. A significant inverse correlation was found between TCV and Δβ2M (r = -0.627; p < 0.0001), and TCV and ΔhsCRP (r = -0.514; p < 0.0001); no correlation between TCV and ΔESAdose was observed. No correlation was found between eKt/V and Δβ2M, ΔhsCRP, and ΔESAdose. Multiple regression analysis with ΔESAdose as dependent variable showed ΔhsCRP as the only significantly associated independent factor (p < 0.01). CONTROL GROUP: no significant variations of hsCRP, β2M, and ESAdose were observed over time. CONCLUSIONS: Ol-HDF induces a long-term significant reduction in pre-dialysis β2M and hsCRP concentrations. The magnitude of reduction is directly correlated to the amount of TCV achieved but not on eKt/V. The observed reduction in ESAdose requirement is independent either on convection or diffusion, but is directly associated to the concomitant reduction of inflammation

Magnitude of End-Dialysis Overweight is Associated with All-Cause and Cardiovascular Mortality: A 3-Year Prospective Study.

9Background: We hypothesized that the difference between the prescribed end-dialysis body weight, defined end-dialysis over-weight (edOW; kg), and the body weight which is actually attained could impact survival in hemodialysis (HD) patients. The aim of this prospective observational study was to evaluate if edOW could influence survival in a cohort of prevalent HD patients, controlled for multiple dialysis and clinical risk factors and followed for 3 years. Methods: One hundred and eighty-two patients (117 men, age 65 ± 13 years) on regular HD treatment for at least 6 months [median 48 months (range: 6-366)] were followed from January 1, 2008 to December 31, 2010. Eighty-four patients (46%) did not achieve their prescribed dry body weight (dBW); their median edOW was 0.4 kg (range: 0.1-1.4). Ninety-eight died during observation, mainly from cardiovascular reasons (69%). Multivariate Cox regression analysis was utilized to evaluate the effect edOW, ultrafiltration rate (UFR), interdialytic weight gain (IDWG), age, sex, dialytic vintage, cardiovascular disease, antihypertensive therapy, diabetes, duration of HD, dBW, BMI, mean arterial blood pressure, Kt/V, and protein catabolic rate (PCRn) had on mortality. Results: Age (HR: 1.04; CI: 1.03-1.05; p <0.0001), IDWG (HR: 2.62; CI: 2.06-3.34; p < 0.01), UFR (HR: 1.13; CI: 1.09-1.16; p< 0.01), PCRn (HR: 0.02; CI: 0.01-0.04; p <0.001), and edOW (HR: 2.71; CI: 1.95-3.75; p < 0.02) were independently correlated to survival. The relative receiver operating characteristic curve identified a cutoff value of 0.3 kg for edOW in predicting death. Conclusions: High edOW is independently associated with an increased long-term risk of all-cause and cardiovascular mortality in HD patients. Better survival was observed in patients with edOW <0.3 kg. For patients with higher edOW, longer or more frequent dialysis sessions should be considered in order to prevent the deleterious consequences of excessive body fluid expansionreservedmixedMovilli, E.; Camerini, C.; Gaggia, P.; Zubani, R.; Feller, P.; Poiatti, P.; Pola, A.; Carli, O.; Cancarini, G.Movilli, Ezio; Camerini, Corrado; Gaggia, Paola; Zubani, Roberto; Feller, P.; Poiatti, P.; Pola, A.; Carli, O.; Cancarini, Giovann