31 research outputs found
Robot-assisted splenectomy in a teenager with chronic autoimmune thrombocytopenia
The use of the Da Vinci Xi system is gaining popularity among all surgical disciplines. A splenectomy is a treatment option for patients with hematological disorders and splenic lesions. The laparoscopic approach is nowadays the standard of care. Despite the initial controversy, recently it has been demonstrated the superiority of robotic splenectomy performed in ''difficult'' cases. We report, to our knowledge, the first case of robot-assisted splenectomy following embolization of the splenic artery in a 15-year-old patient with chronic immune thrombocytopenia, worsened by a severe cerebral sinus thrombosis, while being treated with eltrombopag and mycophenolate. Due to the need for a rapid rise in platelet counts and failure of several medical treatments, splenectomy was advocated. To raise the platelet count pre-operatively and minimize intraoperative bleeding, the embolization of the spleen artery was performed before the planned splenectomy. The intervention was carried on without any complication and at 1 year follow up the patient is in good clinical condition and has improved his neurological condition. We propose a robotic splenectomy following embolization of the splenic artery as a feasible and safe procedure. The advantages of the Da Vinci Xi system are highlighted especially in complex cases, requiring maximum precision
Genomic traits of Klebsiella oxytoca DSM 29614, an uncommon metal-nanoparticle producer strain isolated from acid mine drainages
Abstract
Background: Klebsiella oxytoca DSM 29614 - isolated from acid mine drainages - grows anaerobically using Fe(III)- citrate as sole carbon and energy source, unlike other enterobacteria and K. oxytoca clinical isolates. The DSM 29614 strain is multi metal resistant and produces metal nanoparticles that are embedded in its very peculiar capsular exopolysaccharide. These metal nanoparticles were effective as antimicrobial and anticancer compounds, chemical catalysts and nano-fertilizers.
Results: The DSM 29614 strain genome was sequenced and analysed by a combination of in silico procedures. Comparative genomics, performed between 85 K. oxytoca representatives and K. oxytoca DSM 29614, revealed that this bacterial group has an open pangenome, characterized by a very small core genome (1009 genes, about 2%), a high fraction of unique (43,808 genes, about 87%) and accessory genes (5559 genes, about 11%). Proteins belonging to COG categories âCarbohydrate transport and metabolismâ (G), âAmino acid transport and metabolismâ (E), âCoenzyme transport and metabolismâ (H), âInorganic ion transport and metabolismâ (P), and âmembrane biogenesis-related proteinsâ (M) are particularly abundant in the predicted proteome of DSM 29614 strain. The results of a protein functional enrichment analysis - based on a previous proteomic analysis â revealed metabolic optimization during Fe(III)- citrate anaerobic utilization. In this growth condition, the observed high levels of Fe(II) may be due to different flavin metal reductases and siderophores as inferred form genome analysis. The presence of genes responsible for the synthesis of exopolysaccharide and for the tolerance to heavy metals was highlighted too. The inferred genomic insights were confirmed by a set of phenotypic tests showing specific metabolic capability in terms of i) Fe2+ and exopolysaccharide production and ii) phosphatase activity involved in precipitation of metal ion-phosphate salts.
Conclusion: The K. oxytoca DSM 29614 unique capabilities of using Fe(III)-citrate as sole carbon and energy source in anaerobiosis and tolerating diverse metals coincides with the presence at the genomic level of specific genes that can support i) energy metabolism optimization, ii) cell protection by the biosynthesis of a peculiar exopolysaccharide armour entrapping metal ions and iii) general and metal-specific detoxifying activities by different proteins and metabolites
Adrenal venous sampling in dye-allergic primary aldosteronism patients: prevalence, pitfalls and a possible solution
The Key Role of CT for Success of Adrenal Venous Sampling Illustrated by a Unique Clinical Case
A broad mercury resistant strain of Pseudomonas putida secretes pyoverdine under limited iron conditions and high mercury concentrations
The Pseudomonas putida FB1, known as a
broad-spectrum mercury resistant strain, becomes
yellow-green due to the secretion of pyoverdine
(PVDs) under limited iron conditions and high mercury
concentrations. Different modified Nelsonâs
media were obtained by adding mercury, iron, and
the complexing agent nitrilotriacetic acid to demonstrate
that the strain produces only the highest
concentrations of PVDs due to the induction with
25 lM Hg2
?. An amount of 250 mg PVDs was
purified from the supernatant of 1 litre culture. The
various forms of PVDs were characterized using
different techniques such as fluorescence spectroscopy,
high performance liquid chromatography
coupled with high resolution mass spectrometry, and
scanning electron microscope equipped with energy
dispersive X-ray analyser. A set of ââin vivoââ experiments
demonstrated that additions of Hg2? to the
cultures from 10 to 25 lM Hg2? stimulate an over
secretion of PVDs suggesting that the toxic cation
strongly reduces the availability of apo-PVDs,
because the complex mercuric-pyoverdine is very
stable at neutral pH, and hinder the formation of
PVDs-Fe(III).The Pseudomonas putida FB1, known as a broad-spectrum mercury resistant strain, becomes yellow-green due to the secretion of pyoverdine (PVDs) under limited iron conditions and high mercury concentrations. Different modified Nelson's media were obtained by adding mercury, iron, and the complexing agent nitrilotriacetic acid to demonstrate that the strain produces only the highest concentrations of PVDs due to the induction with 25 A mu M Hg2+. An amount of 250 mg PVDs was purified from the supernatant of 1 litre culture. The various forms of PVDs were characterized using different techniques such as fluorescence spectroscopy, high performance liquid chromatography coupled with high resolution mass spectrometry, and scanning electron microscope equipped with energy dispersive X-ray analyser. A set of "in vivo" experiments demonstrated that additions of Hg2+ to the cultures from 10 to 25 A mu M Hg2+ stimulate an over secretion of PVDs suggesting that the toxic cation strongly reduces the availability of apo-PVDs, because the complex mercuric-pyoverdine is very stable at neutral pH, and hinder the formation of PVDs-Fe(III)
Blood oozing: A cause of life-threatening bleeding without overt source after transcatheter aortic valve replacement
BACKGROUND:
Post-procedure non-access site-related bleedings have a significant impact on mortality in patients treated by transcatheter aortic valve replacement (TAVR). Notwithstanding, the source of these bleedings is frequently indeterminate, with potentially serious clinical implications related to lack of diagnosis and treatment.
METHODS:
Out of 513 TAVR performed between June 2007 and January 2016 in the Interventional Cardiology Laboratory of the Department of Cardiac, Thoracic and Vascular Sciences, University Hospital of Padua, we identified few proven cases of concealed bleeding after TAVR due to blood oozing.
RESULTS:
We report three cases of angiographically confirmed post-TAVR non-access bleedings related to spontaneous blood oozing, a life-threatening condition consisting of diffuse capillary hemorrhage developing from vessels not directly involved by the procedure. We hypothesize that spontaneous post-procedural blood oozing may account for a substantial proportion of non-overt, non-access site-related bleeding after TAVR.
CONCLUSION:
The possibility of post-TAVR blood oozing is largely neglected in the literature, and comprehensive categorization of non-access site bleedings in current standardized endpoints of TAVR studies is missing. Early assessment with arterial and venous contrast phase angio-MDCT scans in case of post-TAVR unexplained and persistent anemia may allow diagnosis and treatment of this subtle condition
An extracellular polymeric substance quickly chelates mercury(II) with N-heterocyclic groups
A strain of Klebsiella oxytoca DSM 29614 is grown on sodium citrate in the presence of 50 mg lâ1 of Hg as Hg(NO3)2. During growth, the strain produces an extracellular polymeric substance (EPS), constituted by a mixture of proteins and a specific exopolysaccharide. The protein components, derived from the outer membrane of cells, are co-extracted with the extracellular exopolysaccharide using ethanol. The extracted EPS contains 7.5% of Hg (total amount). This indicates that EPS is an excellent material for the biosorption of Hg2+, through chemical complexation with the EPS components. The binding capacity of these species towards Hg2+ is studied by cyclic voltammetry, and Hg L3-edge XANES and EXAFS spectroscopy. The results found indicate that Hg2+ is mainly bound to the nitrogen of the imidazole ring or other N-heterocycle compounds. The hydroxyl moities of sugars and/or the carboxyl groups of two glucuronic acids in the polysaccharide can also play an important role in sequestring Hg2+ ions. However, N-heterocyclic groups of proteins bind Hg2+ faster than hydroxyl and carboxyl groups of the polysaccharide
Comparison of Cortisol, Androstenedione and Metanephrines to Assess Selectivity and Lateralization of Adrenal Vein Sampling in Primary Aldosteronism
Success of adrenal vein sampling (AVS) is verified by the selectivity index (SI), i.e., by a step-up of cortisol levels between the adrenal vein and the infrarenal inferior vena cava samples, beyond a given cut-off. We tested the hypothesis that androstenedione, metanephrine, and normetanephrine, which have higher gradients than cortisol, could increase the rate of AVS studies judged to be bilaterally successful and usable for the clinical decision making. We prospectively compared within-patient, head-to-head, the selectivity index of androstenedione (SIA), metanephrine (SIM), and normetanephrine (SINM), and cortisol (SIC) in consecutive hypertensive patients with primary aldosteronism submitted to AVS. Main outcome measures were rate of bilateral success, SI values, and identification of unilateral PA. We recruited 136 patients (55 + 10 years, 35% women). Compared to the SIC, the SIA values were 3.5-fold higher bilaterally, and the SIM values were 7-fold and 4.4-fold higher on the right and the left side, respectively. With the SIA and the SIM the rate of bilaterally successful AVS increased by 14% and 15%, respectively without impairing the identification of unilateral PA. We concluded that androstenedione and metanephrine outperformed cortisol for ascertaining AVS success, thus increasing the AVS studies useable for the clinical decision making
Metoclopramide unmasks potentially misleading contralateral suppression in patients undergoing adrenal vein sampling for primary aldosteronism
Pickering Syndrome: An Overlooked Renovascular Cause of Recurrent Heart Failure
: ABSTRACTRecurring and rapidly developing (flash) pulmonary edema is the hallmark of Pickering syndrome, affecting patients with hypertension and atherosclerotic renal artery stenosis (either bilateral or unilateral) in a solitary functioning kidney, and impaired renal function. We herein report on a series of consecutive patients with recurrent hospital admissions for pulmonary edema, impaired renal function (chronic kidney disease class 4-5), and atherosclerotic bilateral renal artery stenosis, in whom Pickering syndrome had been long neglected. We also describe a streamlined diagnostic strategy entailing little or no need for contrast medium, thus carrying no risks of further worsening of renal function. This allowed us to make the correct diagnosis and opened the way to revascularization by percutaneous transluminal renal angioplasty with stent, which provided swift recovery of kidney function with resolution of pulmonary congestion and long-term pulmonary edema- and dialysis-free survival in all cases. In summary, these findings support the following key messages: (1) considering the diagnosis of Pickering syndrome, followed by searching atherosclerotic renal artery stenosis, is an essential step toward a life-saving revascularization that avoids dialysis and an otherwise poor outcome; and (2) a simplified strategy entailing little or no need for contrast medium, carrying no associated risks of deteriorating renal function, permits the diagnosis of Pickering syndrome