Assessment of Spleen Filtrate Function in Renal Transplant Recipients Using Technetium-99m Stannous Colloid Liver-Spleen Scan.

BACKGROUND: Functional hyposplenism (FH) is indicated by an anatomically present spleen that fails to take up radiolabeled colloid. The occurrence of FH has been reported in a small group of renal transplant recipients based on hematologic parameters. The aim of this study was to replicate this association in a larger group of renal transplant recipients with the use of technetium-99m-stannous colloid liver-spleen scan to assess the spleen function. METHODS: This survey based on single samples enrolled 101 unselected adult patients with functional kidney grafts >180 days after transplantation. All patients underwent 99mTc-stannous colloid scan to assess spleen function as well as bone marrow uptake of radiocolloid along with an anatomic and blood flow study of the spleen and kidney with the use of Doppler sonography. RESULTS: The prevalence of hyposplenism was 32.7% (33/101) for the cohort, and increased uptake of radiocolloid by the bone marrow was seen in 9.9% (10/101). According to the multivariate analysis, the frequency of hyposplenism was significantly influenced by indirect bilirubin and hemoglobin, and direct bilirubin and neutrophil count remained as independent predictors of bone marrow uptake. CONCLUSIONS: This study demonstrated that a group of renal transplant recipients has FH. In addition, bone marrow uptake might be interpreted as liver dysfunction. In this situation, the small amount of contrast (spleen compared with liver) would leave hyposplenism undiagnosed. Further prospective and longitudinal clinical studies are needed to determine the clinical impact of this condition on the management of renal transplant recipients.

Determinant Variables of Resistive Index in Early Renal Transplant Recipients.

BACKGROUND: The resistive index (RI) is used to evaluate renal allograft perfusion and dysfunction. Whereas the RI prognostic role for graft function has received considerable attention, less attention was paid to potential determinants of RI. The aim of this study was to present the results of interlobar artery RI, with special attention given to variables associated with it within 1 week posttransplantation. METHODS: In 125 patients, the association of several variables with the RI grouped in tertiles was assessed. RESULTS: Thirty-eight subjects had an RI ≤ 0.67 (30.4%), Group 1; 44 an RI > 0.67 and ≤0.76 (35.2%), Group 2; and 43 an RI ≥ 0.77 (34.4%), Group 3. In the univariate analysis, Group 1 was younger (P < .05), Group 2 had a shorter pretransplantation duration of dialysis (P < .05), and Group 1 had less tubular necrosis (P < .05). In the multivariate analysis, recipient age and tubular necrosis remained as independent predictors of RI values (P < .05). There was a nonlinear association between RI and dialysis duration. DISCUSSION: Our study confirms that RI has a linear, significant association with recipient age and tubular necrosis, and a nonlinear association with dialysis duration.

Dried blood spots of pooled samples for RHD gene screening in blood donors of mixed ancestry.

OBJECTIVES: In this study, we present a strategy for RHD gene screening based on real-time polymerase chain reaction (PCR) using dried blood spots of pooled samples. BACKGROUND: Molecular analysis of blood donors may be used to detect RHD variants among the presumed D-negative individuals. RHD genotyping using pooled samples is a strategy to test a large number of samples at a more reasonable cost. MATERIALS AND METHODS: RHD gene detection based on real-time PCR using dried blood spots of pooled samples was standardised and used to evaluate 1550 Brazilian blood donors phenotyped as RhD-negative. Positive results were re-evaluated by retesting single samples using real-time PCR and conventional multiplex PCR to amplify five RHD-specific exons. PCR-sequence-specific primers was used to amplify RHDψ allele. RESULTS: We devised a strategy for RHD gene screening using dried blood spots of five pooled samples. Among 1550 serologically D-negative blood donors, 58 (3.74%) had the RHD gene. The non-functional RHDψ allele was detected in 47 samples (3.02%). CONCLUSION: The present method is a promising strategy to detect the RHD gene among presumed RhD-negative blood donors, particularly for populations with African ancestry.

Effect of rapamycin on spleen size in longstanding renal transplant recipients.

BACKGROUND: Based on evidence available in the literature, rapamycin, a mammalian target of rapamycin (mTOR) inhibitor, but not calcineurin inhibitors (CNIs), has been shown to decrease spleen size. Small spleen, in some instances, is associated with hyposplenism, a condition recently reported in patients with longstanding renal transplant. Accordingly, the effect of immunosuppressive drugs on spleen size was evaluated. METHODS: Renal transplant recipients (35 taking mTOR and 68 CNI) were included, in whom a standardized investigation of the kidney allograft and spleen with the use of color Doppler ultrasound was performed and a peripheral smear were reviewed for the presence of Howell-Jolly bodies (HJBs). RESULTS: We enrolled 103 patients (64 men; 66 from a deceased donor). The mean age was 47.7 years (range, 23.0-74.0 y). Mean transplant duration was 1,899 days (range, 181-6,883 d). According to the presence of HJBs, the prevalence of hyposplenism was 47.6% for the entire cohort. The differences between the mTOR and CNI groups regarding sex and the presence of HJBs were not statistically significant (P > .05). Age, creatinine, hemoglobin, leukocytes, platelets, and Doppler parameters in spleen and kidney were similar in both groups (P > .05). mTOR patients had a decreased spleen length size (90.09 ± 13.02 mm vs 111.95 ± 18.66 mm; P < .001), a longer transplant duration (3,576 ± 1,594 d vs 1,036 ± 1,369 d; P < .001) and higher serum cholesterol (227.50 ± 38.75 mg/dL vs 182.67 ± 37.74 mg/dL; P < .001) and triglycerides (194.23 ± 79.88 mg/dL vs 148.70 ± 55.54 mg/dL; P = .003) levels compared with the CNI group. A multivariate analysis showed mTOR inhibitor to be the most important predictor of spleen size. In both the mTOR and CNI groups, the comparison between the subgroups of present and absent HJBs did not show any difference. CONCLUSIONS: The findings of this study suggest that small spleens in transplant recipients may be linked to treatment with an mTOR inhibitor, although this apparently does not compromise splenic function.

Photodynamic antimicrobial therapy of curcumin in biofilms and carious dentine.

Photodynamic therapy (PDT) is a technique that involves the activation of photosensitizers by light in the presence of oxygen, resulting in the production of reactive radicals that are capable of inducing cell death. The present study evaluated the susceptibility of Streptococcus mutans and Lactobacillus acidophilus to PDT grown as multi-species in the biofilm phase versus in dentine carious lesions. A brain-heart infusion culture medium supplemented with 1% glucose, 2% sucrose, and 1% young primary culture of L. acidophilus 10(8) CFU/mL and S. mutans 10(8) CFU/mL was used to develop multi-species biofilms and to induce caries on human dentine slabs. Five different concentrations of curcumin (0.75, 1.5, 3.0, 4.0, and 5.0 g/L) were used associated with 5.7 J/cm(2) light emission diode. Four different groups were analyzed L-D- (control group), L-D+ (drug group), L+D- (light group), and L+D+ (PDT group). ANOVA/Tukey's tests were conducted to compare groups. A significant reduction (p <0.05) in cell viability was observed in the biofilm phase following photosensitization with all curcumin concentrations tested. To achieve significant bacterial reduction (p <0.05) in carious dentine, it was necessary to utilize 5.0 g/L of curcumin in association with blue light. No significant reduction was found for L-D+, supporting the absence of the drug's dark toxicity. S. mutans and L. acidophilus were susceptible to curcumin in the presence of blue light. However, due to light penetration and drug diffusion difficulties, these microorganisms within dentine carious lesions were less affected than they were in the biofilm phase.

Peroxides with antiplasmodial activity inhibit proliferation of Perkinsus olseni, the causative agent of Perkinsosis in bivalves.

Perkinsus olseni, the causative agent of Perkinsosis, can drastically affect the survival of target marine mollusks, with dramatic economic consequences for aquaculture. P. olseni is a member of the Alveolata group, which also comprises parasites that are highly relevant for medical and veterinary sciences such as Plasmodium falciparum and Toxoplasma. P. olseni shares several unique metabolic pathways with those pathological parasites but is not toxic to humans. In this work, six antimalarially active peroxides, derived from the natural product artemisinin or synthetic trioxolanes, were synthesized and tested on P. olseni proliferation and survival. All peroxides tested revealed an inhibitory effect on P. olseni proliferation at micromolar concentrations. The relevance of the peroxide functionality on toxicity and the effect of Fe(II)-intracellular concentration on activity were also evaluated. Results demonstrated that the peroxide functionality is the toxofore and intracellular iron concentration also proved to be a crucial co-factor on the activation of peroxides in P. olseni. These data points to a mechanism of bioactivation in P. olseni sharing similarities with the one proposed in P. falciparum parasites. Preliminary studies on bioaccumulation were conducted using fluorescent-labeled peroxides. Results show that synthetic trioxolanes tend to accumulate on a vacuole while the labeled artemisinin accumulates in the cytoplasm. Preliminary experiments on differential genes expression associated to Fe(II) transport protein (Nramp) and calcium transport protein (ATP6/SERCA) were also conducted by qPCR. Results point to a fourfold increase in expression of both genes upon exposure to trioxolanes and approximately twofold upon exposure to artemisinin derivatives. Data obtained in this investigation is relevant for better understanding of the biology of Perkinsus and may also be important in the development of new strategies for Perkinsosis prevention and control.

Functional hyposplenism in long-standing renal transplant recipients.

BACKGROUND: A nephrologist with expertise in ultrasonography noticed that patients with longstanding renal grafts had smaller spleens than subjects undergoing initial post-transplantation imaging. This putative finding prompted us to pursue a further investigation into splenic function based on Doppler ultrasound and hematologic parameters. METHODS: We enrolled 47 patients with functioning long-standing kidney grafts, measuring longitudinal diameter of the spleen, hilar and intrasplenic peak systolic velocities (PSV), and hilar and intrasplenic resistivity indices of the splenic artery as well as mean arterial blood pressure (MAP). Giemsa-stained peripheral blood smears were examined for the presence of Howell-Jolly bodies (HJBs) using light microscopy. The patients were then divided into HJB present (HJ(+)) or absent (HJ(-)) groups for further comparison. RESULTS: The overall mean age of 21 females and 26 males was 47.8 ± 12.0 years, and the mean time after transplantation was 2750 ± 1818 days (range, 208-6446). HJBs were detected in 23/47 patients (48.9%). The intrasplenic artery PSV was significantly lower and MAP higher in the HJ(+) group (P < .05). There was no difference in spleen size between the groups. DISCUSSION: HJBs in peripheral blood red cells, an indicator of hyposplenism, was associated with reduced intrasplenic artery PSV, suggesting dysfunction, which may play a role in the known vulnerability of renal transplant recipients to infections.

Epidural abscess due to Salmonella enteritidis in a patient with systemic lupus erythematosus.

Increased susceptibility to infection has long been observed among patients with systemic lupus erythematosus, and still represents a chief cause of morbidity and mortality in these patients. This is due in part to the severity of infection and to the difficulty of early diagnosis owing to the similarity between SLE flares and infection. Epidural infection is an uncommon condition, and a most rare condition caused by salmonella, which accounts for a broad spectrum of human illnesses from gastroenteritis and typhoid fever to the asymptomatic carrier state. We report the first case of epidural abscess caused by Salmonella enteritidis in a female with SLE with protean manifestations treated by intravenous antibiotics and surgery with full recovery of neurological symptoms, illustrating the importance of performing an early diagnosis and prompt treatment.

Study of urinary acidification in patients with idiopathic hypocitraturia.

Hypocitraturia (HCit) is one of the most remarkable features of renal tubular acidosis, but an acidification defect is not seen in the majority of hypocitraturic patients, whose disease is denoted idiopathic hypocitraturia. In order to assess the integrity of urinary acidification mechanisms in hypocitraturic idiopathic calcium stone formers, we studied two groups of patients, hypocitraturic (HCit, N = 21, 39.5 +/- 11.5 years, 11 females and 10 males) and normocitraturic (NCit, N = 23, 40.2 +/- 11.7 years, 16 females and 7 males) subjects, during a short ammonium chloride loading test lasting 8 h. During the baseline period HCit patients showed significantly higher levels of titratable acid (TA). After the administration of ammonium chloride, mean urinary pH (3rd to 8th hour) and TA and ammonium excretion did not differ significantly between groups. Conversely, during the first hour mean urinary pH was lower and TA and ammonium excretion was higher in HCit. The enhanced TA excretion by HCit during the baseline period and during the first hour suggests that the phosphate buffer mechanism is activated. The earlier response in ammonium excretion by HCit further supports other evidence that acidification mechanisms react promptly. The present results suggest that in the course of lithiasic disease, hypocitraturia coexists with subtle changes in the excretion of hydrogen ions in basal situations.

Study of urinary acidification in patients with idiopathic hypocitraturia

Hypocitraturia (HCit) is one of the most remarkable features of renal tubular acidosis, but an acidification defect is not seen in the majority of hypocitraturic patients, whose disease is denoted idiopathic hypocitraturia. In order to assess the integrity of urinary acidification mechanisms in hypocitraturic idiopathic calcium stone formers, we studied two groups of patients, hypocitraturic (HCit, N = 21, 39.5 + or - 11.5 years, 11 females and 10 males) and normocitraturic (NCit, N = 23, 40.2 + or - 11.7 years, 16 females and 7 males) subjects, during a short ammonium chloride loading test lasting 8 h. During the baseline period HCit patients showed significantly higher levels of titratable acid (TA). After the administration of ammonium chloride, mean urinary pH (3rd to 8th hour) and TA and ammonium excretion did not differ significantly between groups. Conversely, during the first hour mean urinary pH was lower and TA and ammonium excretion was higher in HCit. The enhanced TA excretion by HCit during the baseline period and during the first hour suggests that the phosphate buffer mechanism is activated. The earlier response in ammonium excretion by HCit further supports other evidence that acidification mechanisms react promptly. The present results suggest that in the course of lithiasic disease, hypocitraturia coexists with subtle changes in the excretion of hydrogen ions in basal situations

[Mineral waters from several Brazilian natural sources]. / Aguas minerais de algumas fontes naturais brasileiras.

PURPOSE: To divulge information on the chemical composition and physical-chemical features of some mineral waters from Brazilian natural sources that will be of useful protocol investigation and patient advice. METHODS: The survey was based on bottle labels of non-gaseous mineral waters commercially available in the city of Rio de Janeiro. The íon concentration of each mineral was calculated from the salt content. RESULTS: 36 springs were enralled from different states of the country. The pH (25 degrees C), 4.1 to 9.3, varied on dependence of the source and it was linearey correlated with the cations calcium, magnesium and sodium and the anion bicarbonate. It was atributed to high alkalinity (about 70% of bicarbonate in the molecula-gram) of these salts. The calcium (0.3 to 42 mg/l), magnesium (0.0 to 18 mg/l) and bicarbonate (4 to 228 mg/l) contents are relatively low. CONCLUSION: The mineral content of the Brazilian springs enrolled in this survey is low; about 70% of the sources having calcium and magnesium less than 10 mg/l and 1.0 mg/l, respectively, similar to local tap water.

Aguas minerais de algumas fontes naturais brasileiras / Mineral waters from Brazilian natural sources

Paciente de litíase renal é estimulado a aumentar a ingestão hídrica, principalmente na forma de água tratada da torneira, pela irrelevante biodisponibilidade de mineerais em sua composição. O benefício é atribuído à redução da saturação dos sais urinários. Não está claro se as águas minerais naturais comercialmente disponíveis também é benéfica. Objetivo. Divulgar as informações sobre as características químicas e físico-químicas de águas minerais naturais de algumas das diversas fontes brasileiras. Essas informações serão de utilidade na análise de protocolos de pesquisa e na orientação do paciente. Métodos. Foi feito uma coletânea das informações que constam nos rótulos de garrafas de águas minerais naturais, predominantemente não-gasosas, acessíveis ao consumo carioca. A partir da composição salina provável, foi calculada a concentração iônica de cada mineral. Resultados. Foram estudadas as informações de 36 fontes situadas em alguns estados brasileiros. O pH, a 25 graus Celsius, variou de 4,1 a 9,3 na dependência da fonte e foi linearmente correlacionando com as concentrações dos cátions cálcio, magnésio, sódio e do anion bicarbonato. Isto foi atribuído à alta alcalinidade desses sais, que contêm cerca de 70 por cento de bicarbonato na molécula. Os teores de cálcio (0,3 a 42 mg/l), de magnésia (0,0 a 18 mg/l) e de bicarbonato (4 a 228 mg/l) foram considerados relativamente baixos. Conclusão. O teor mineral das fontes brasileiras que compuseram esse levantamente é baixo, com cerca de 70 por cento delas apresentando teores de cálcio e de magnésio abaixo de 10 mg/l e 1 mg/l, respectivamente, semelhantes ao da água tratada da torneira.