4D Flow MRI in the portal venous system: imaging and analysis methods,and clinical applications

La radiologia medica - Thus far, ultrasound, CT, and 2D cine phase-contrast MRI has been adopted to evaluate blood flow and vascular morphology in the portal venous system; however, all these...     

A single and novel natriuretic peptide is expressed in the heart and brain of the most primitive vertebrate,the hagfish (Eptatretus burgeri)

In teleost fish and tetrapods, the natriuretic peptide (NP) family consists of ANP (atrial natriuretic peptide), BNP (brain natriuretic peptide) and VNP (ventricular natriuretic peptide) that are secreted from the heart, and C-type natriuretic peptide (CNP) that is found in the brain. However, CNP is the only NP identified in the heart and brain of elasmobranchs, suggesting that it is the ancestral type of the NP family and that ANP, BNP and VNP appeared later in the vertebrate phylogeny. To delineate more clearly the molecular evolution of this hormone family, we determined the sequence of NP molecule(s) in evolutionarily the oldest vertebrate group, the cyclostomes. We have cloned a novel NP cDNA from the heart and brain of hagfish, Eptatretus burgeri, using the RACE method and degenerate primers that amplify all known types of NP cDNAs. The novel NP, named EbuNP after the scientific name of this hagfish, appears to be the only NP in the heart and brain, as no other NP cDNAs were amplified even after specific removal of the cloned EbuNP mRNA from the mRNA pool, except for a minor alternatively spliced EbuNP cDNA with a truncated 3'-untranslated sequence. The EbuNP was equally similar to known NPs but was not considered to be a CNP because of the presence of a C-terminal tail sequence. The EbuNP gene was abundantly expressed in the cardiac atrium, ventricle, portal heart and brain but scarcely in the intestine; no expression was observed in the gill and kidney. Mass spectrometry of affinity-purified EbuNP in plasma, heart and brain revealed a 68 amino acid peptide circulating in the blood and stored in the heart, which is cleaved at the typical cleavage signal of a processing enzyme, furin, as observed in mammalian BNP. The C-terminal Gly residue was used for amidation as is the case in eel ANP. The immunoreactive EbuNP was not detected in the brain, suggesting the presence of a different processing form in the brain. These results show that the molecular evolution of the NP family in vertebrates is more complex than previously thought.     

Optimized scan delay for late hepatic arterial or pancreatic parenchymal phase in dynamic contrast-enhanced computed tomography with bolus-tracking method

Objectives:To determine the optimal scan delay corresponding to individual hemodynamic status for pancreatic parenchymal phase in dynamic contrast-enhanced CT of the abdomen.Methods:One hundred and fourteen patients were included in this retrospective study (69 males and 45 females; mean age, 67.9 ± 12.1 years; range, 39–87 years). These patients underwent abdominal dynamic contrast-enhanced CT between November 2019 and May 2020. We calculated and recorded the time from contrast material injection to the bolus-tracking trigger of 100 Hounsfield unit (HU) at the abdominal aorta (s) (Time_TRIG) and scan delay from the bolus-tracking trigger to the initiation of pancreatic parenchymal phase scanning (s) (Time_SD). The scan delay ratio (SDR) was defined by dividing the Time_SD by Time_TRIG. Non-linear regression analysis was conducted to assess the association between CT number of the pancreas and SDR and to reveal the optimal SDR, which was ≥120 HU in pancreatic parenchyma.Results:The non-linear regression analysis showed a significant association between CT number of the pancreas and the SDR (p < 0.001). The mean Time_TRIG and Time_SD were 16.1 s and 16.8 s, respectively. The SDR to peak enhancement of the pancreas (123.5 HU) was 1.00. An SDR between 0.89 and 1.18 shows an appropriate enhancement of the pancreas (≥120 HU).Conclusion:The CT number of the pancreas peaked at an SDR of 1.00, which means Time_SD should be approximately the same as Time_TRIG to obtain appropriate pancreatic parenchymal phase images in dynamic contrast-enhanced CT with bolus-tracking method.Advances in knowledge:The hemodynamic state is different in each patient; therefore, scan delay from the bolus-tracking trigger should also vary based on the time from contrast material injection to the bolus-tracking trigger. This is necessary to obtain appropriate late hepatic arterial or pancreatic parenchymal phase images in dynamic contrast-enhanced CT of the abdomen.     

Urinary reconstruction in vertebral,anorectal, cardiac,trachea‐esophageal,renal abnormalities and limb defects association with chronic renal failure and penile duplication

Various urological complications in VATER association require careful management. A 15‐year‐old boy with VATER association, including a hypoplastic lower urinary tract and diphallia, presented with chronic kidney disease and incontinence after a right loop ureterostomy. In order to acquire urinary continence without renal function impairment, an ileocecal reservoir with umbilical catheterizable stoma was created as a urinary reconstruction. The ectopic posterior penis was resected for cosmetic reasons, and the stump of the hypoplastic urethra was opened at the perineal skin. Clean intermittent self‐catheterization through the umbilicus using disabled bilateral limbs was then achieved. This report describes the management of VATER association in a patient with complicated urological anomalies.     

High concentrations of human β-defensin 2 in gastric juice of patients with Helicobacter pyloriinfection

AIM: Human beta-defensin (HBD)-1 and HBD-2 are endogenous antimicrobial peptides. Unlike HBD-1, the HBD-2 expression is augmented by Helicobacter pylori (H pylori). We sought to determine HBD-1 and HBD-2 concentrations in gastric juice during H pylori infection. METHODS: HBD-1 and HBD-2 concentrations were measured by radioimmunoassay in plasma and gastric juice of 49 H pylori-infected and 33 uninfected subjects and before and after anti-H pylori treatment in 13 patients with H pylori-associated gastritis. Interleukin (IL)-1beta and IL-8 concentrations in gastric juice were measured by enzyme-linked immunosorbent assay (ELISA). Histological grades of gastritis were determined using two biopsy specimens taken from the antrum and corpus. Reverse phase high performance liquid chromatography (RP-HPLC) was used to identify HBD-2. RESULTS: HBD-2 concentrations in gastric juice, but not in plasma, were significantly higher in H pylori-positive than -negative subjects, albeit the post-treatment levels were unchanged. Immunoreactivity for HBD-2 was exclusively identified in H pylori-infected mucosa by RP-HPLC. HBD-2 concentrations in gastric juice correlated with histological degree of neutrophil and mononuclear cell infiltration in the corpus. IL-1beta levels correlated with those of IL-8, but not HBD-2. Plasma and gastric juice HBD-1 concentrations were similar in H pylori-infected and uninfected subjects. CONCLUSION: Our results place the beta-defensins, especially HBD-2, in the front line of innate immune defence. Moreover, HBD-2 may be involved in the pathogenesis of H pylori-associated gastritis, possibly through its function as immune and inflammatory mediator.