Mechanisms of cell signaling by nitric oxide and peroxynitrite: from mitochondria to MAP kinases

Many of the biological and pathological effects of nitric oxide (NO) are mediated through cell signaling pathways that are initiated by NO reacting with metalloproteins. More recently, it has been recognized that the reaction of NO with free radicals such as superoxide and the lipid peroxyl radical also has the potential to modulate redox signaling. Although it is clear that NO can exert both cytotoxic and cytoprotective actions, the focus of this overview are those reactions that could lead to protection of the cell against oxidative stress in the vasculature. This will include the induction of antioxidant defenses such as glutathione, activation of mitogen-activated protein kinases in response to blood flow, and modulation of mitochondrial function and its impact on apoptosis. Models are presented that show the increased synthesis of glutathione in response to shear stress and inhibition of cytochrome c release from mitochondria. It appears that in the vasculature NO-dependent signaling pathways are of three types: (i) those involving NO itself, leading to modulation of mitochondrial respiration and soluble guanylate cyclase; (ii) those that involve S-nitrosation, including inhibition of caspases; and (iii) autocrine signaling that involves the intracellular formation of peroxynitrite and the activation of the mitogen-activated protein kinases. Taken together, NO plays a major role in the modulation of redox cell signaling through a number of distinct pathways in a cellular setting.     

Multiple epithelial cysts of the spleen and on the splenic capsule, and high serum levels of CA19-9, CA125 and soluble IL-2 receptor

An 18-year-old woman with abdominal pain was diagnosed as having splenic cysts by computed tomography scan. She had high serum levels of CA19-9 (2886.8 U/mL; normal value, <35 U/mL), CA125 (131.1 U/mL; normal value, <35 U/mL) and soluble IL-2 receptor (1490 U/mL; normal range, 220-530 U/mL). The resected spleen weighed 1050 g, was 14 x 28 cm, and had more than 10 macroscopic cysts up to 10.3 x 9.5 cm. There were numerous microscopic cysts in the spleen and several on the splenic capsule. The levels of CA19-9 and CA125 in the cyst fluid were 2165550 U/mL and 160400 U/mL, respectively. After the surgery, the serum levels of the tumor markers decreased gradually. The inside of the largest cyst was mainly covered by granulation tissue with a focal lining of epithelial cells, and the other macroscopic cysts had stratified squamous epithelium. The microscopic splenic cysts and cysts on the splenic capsule were lined by either attenuated single-layered or multilayered epithelial cells. The lining epithelial cells of these cysts were positive for epithelial membrane antigen and cytokeratins. CA19-9 and CA125 were detected in the lining cells of the splenic cysts. In the present case, it is suspected that the splenic cysts were derived from the capsular lining cells that showed migration from the capsule or formed microcysts on the splenic capsule, as in the case of ovarian inclusion cysts.     

Pattern of C3, iC3b, and C3d in patients hospitalized for acute asthma.

Twenty-three patients hospitalized for acute asthma were studied for a peripheral blood complement profile consisting of C3, C4, C3d, iC3b, C4d, and Bb concentrations. Compared with normals (n = 22) and patients (n = 10) with acute bacterial infections (ABI), asthmatic patients had significantly higher serum C3 concentrations (P less than .001). Plasma C3d levels and iC3b in asthmatic patients were both comparable to those observed in normal controls, whereas patients with ABI had significantly higher iC3b levels than both other groups. The ratio of iC3b to C3 concentrations were similar in asthmatic patients and controls, and iC3b levels were correlated with total serum C3 levels in asthmatic patients (r = .55, p less than .001) as well as in normal (r = .69, p less than .001). Both of these groups had significantly lower iC3b to C3 ratios compared with the ABI group (P less than .0001). Also observed in asthmatic patients were a significant correlation between serum C4 and C3 levels (r = .83, P less than .001) and a lower mean ratio of plasma C4d to C4 compared with normals (P less than .005). This profile of complement alterations is distinct from that observed in acute bacterial infection. These changes in asthmatic patients may relate to an acute phase reaction phenomenon affecting complement and/or complement regulatory proteins.     

PHENOTYPES OF THE FOURTH COMPLEMENT COMPONENT (C4) IN BLACK AMERICANS FROM THE SOUTHEASTERN UNITED STATES

C4 is composed of two tightly linked genes (C4A and C4B) lying within the major histocompatibility complex of chromosome 6 that can be demonstrated by agarose gel electrophoresis. Seven alleles and five alleles at the C4A and C4B loci, respectively, were detected in 169 black individuals from the southeastern United States. Furthermore, the phenotypic frequencies of C4A6, C4A5, C4A4, C4B4, C4B3, and C4BQO were significantly different between black and white Americans.     

Development of the spine in school children of Lower Silesia

Following on from earlier investigations, spondylometry was once again carried out in 1572 school-children aged between 7 and 14, using an elastometer. The results were analyzed using the "Wroclaw Taxonomy Method" and are presented in the tables in this paper. They confirm that the individual sections of the spine grow at different rates and that the overall length of the spine increases considerably faster during puberty than body height.     

Kinetics and mechanism of the hydrolysis of a 2-substituted imidazoline, cibenzoline (cifenline)

The results of a kinetic and mechanistic study of the hydrolysis of a new antiarrhythmic agent, cibenzoline, are reported. The reaction is subject to specific base catalysis which proceeds via the protonated cibenzolinium ion. No evidence for the existence of a "pseudobase"-type intermediate could be found. The results support only one of two different mechanisms which have been proposed previously for the hydrolysis of this class of compounds.     

Isolation and partial characterization of neurofibrillary tangles and amyloid plaque core in Alzheimer's disease: immunohistological studies

Fractions enriched in neurofibrillary tangles (NFT) and amyloid fibrils were isolated from the cerebral cortex of three cases of senile dementia of the Alzheimer type. Distilled water suspensions of these fractions were excluded from all pore size gels and resisted digestion with various proteolytic enzymes. Formic acid/chloroform treatment of each fraction resulted in the appearance of 4,000-6,000, 15,000-17,000 and 24,000 molecular weight proteins, with concomitant diminution in the amount of excluded material at the top of each gel. The 4,000-6,000 dalton band was best seen in fractions containing randomly arranged amyloid fibrils, and its amino acid composition resembled that of the recently reported "beta" protein. A polyclonal antiserum to purified NFT reacted with tangles in neurons and in dystrophic neurites around plaques by immunoperoxidase staining. No reaction was obtained with cerebrovascular or plaque core amyloid immunohistologically, or with the 4-6 kD protein on immunoblots. Cross-reactivity with the neurofibrillary lesions occurring in Pick's disease, progressive supranuclear palsy, postencephalitic Parkinsonism and dementia pugilistica was also seen. Specific binding of this antiserum to the double filamentous structure was confirmed by immunoelectron microscopy. Although the presence of "beta" protein in both NFT and amyloid-containing fractions suggests that it may be an important constituent of both, cross-contamination cannot be excluded.     

Characteristics affecting cervical sagittal alignment in patients with chronic low back pain

BackgroundSagittal spino-pelvic malalignment in patients with chronic low back pain (CLBP) have been reported in the past, which may also affect cervical spine lesions. The purpose of this study is to investigate the cervical alignment in patients with CLBP.MethodOf the patients who visited an orthopedic specialist due to low back pain lasting more than three months, 121 cases (average 71.5-years-old, 46 male and 75 female) with whole standing spinal screening radiographs were reviewed (CLBP group). Cervical parameters included cervical lordosis (CL), C2–C7 sagittal vertical axis (C2-7 SVA), and the T1 slope minus CL (T1S-CL). Cervical spine deformity was defined as C2-7 SVA >4 cm, CL <0°, or T1S-CL ≧20°. We compared the cervical alignment of these patients with 121 age and gender matched volunteers (control group).ResultsThe prevalence of cervical spine deformity was significantly higher in the CLBP group than in the control group (20.7% vs. 10.7%, P = 0.034). The mean CL was smaller in the CLBP group than in the control group (16.1° vs. 21.4°, P = 0.002). The mean C2-7 SVA was 17.6 mm vs. 18.7 mm in the CLBP group and in the control group, respectively (P = 0.817). The mean T1S-CL was larger in the CLBP group than in the control group (9.1° vs. 3.5°, P < 0.001). Multivariate analysis showed that people with CLBP were more likely to have cervical deformities than people without CLBP (odds ratio 2.16, 95% confidence interval 1.006 to 4.637).ConclusionsThis study results suggest that people with CLBP present with worse cervical sagittal alignment and higher prevalence of cervical spine deformities than age and gender matched volunteers with no CLBP. This means CLBP impacts cervical spine lesions negatively.Level of evidenceⅣ     

Lessons learned from lower urinary tract complications of anorectoplasty for imperforate anus with rectourethral/rectovesical fistula: Laparoscopy-assisted versus posterior sagittal approaches

PurposeTo report the sequelae of and preventive strategies for selected lower urinary tract (LUT) complications, i.e., posterior urethral diverticulum (PUD), intraoperative LUT injuries, postoperative dysuria, and fistula recurrence in male imperforate anus (IA) with rectourethral/rectovesical (RU/RV) fistula after laparoscopy-assisted anorectoplasty (LAARP) or posterior sagittal anorectoplasty (PSARP).Methods153 boys with IA and RU/RV fistula treated 1986–2019 by LAARP (n = 56) or PSARP (n = 97) at two unrelated institutes were studied retrospectively.ResultsAfter mean follow-up of 17.0 years (range: 36.5 days-32.0 years), the overall incidences of LUT complications were: LAARP (6/56; 10.7%); PSARP (7/97; 7.2%); p = 0.55, comprising PUD: LAARP (n = 5), PSARP (n = 0); p = 0.006; injuries: LAARP (n = 0), PSARP (n = 5); p = 0.16; dysuria: LAARP (n = 1), PSARP (n = 1); p>0.999; and recurrence: LAARP (n = 0), PSARP (n = 1); p>0.999. Mean onset of PUD was 5.1 years (range: 1.0–15.1 years). Treatment: PUD: surgery (n = 2/5), conservative (n = 3/5); injuries: intraoperative repair (n = 5/5); dysuria: conservative (n = 2/2), and recurrence: redo PSARP (n = 1/1).ConclusionsStrategies devised to improve dissection accuracy resolved the specific technical issues causing LUT complications (remnant RU fistula dissection in LAARP and blind posterior access in PSARP). Currently, the incidence of new cases of PUD and LUT injuries is zero.Level of Evidence: Level III     

Peliosis Hepatis in a Child with X-Linked Myotubular Myopathy Treated with Living-Donor Liver Transplant: A Case Report

BackgroundMyotubular myopathy is a rare disease sometimes accompanied by peliosis hepatis, a leading cause of fatal liver hemorrhage.Case ReportWe present a case of a 2-year-old boy with myotubular myopathy who developed liver hemorrhage because of peliosis hepatis and was successfully treated with living-donor liver transplant. The patient initially presented with fever, anemia, and liver dysfunction. A computed tomographic scan revealed hemorrhages in the liver, and the patient underwent hepatic artery embolization twice. After the second embolization, multiple peliosis hepatis cavities appeared in the left lobe of the liver that had increased in size. Therefore, the patient underwent ABO-incompatible living-donor liver transplant using a lateral segment graft from his father. The patient developed severe septic shock with an unknown focus on postoperative day 18, which resolved with antibiotic therapy. On postoperative day 62, he was discharged. Fourteen months after undergoing living-donor liver transplant, the patient showed no recurrence of peliosis hepatis.ConclusionsAlthough the long-term prognosis of peliosis hepatis due to myotubular myopathy after living-donor liver transplant remains unclear, liver transplant may be a curative treatment for patients with myotubular myopathy who have uncontrollable peliosis hepatis.