Structure-activity relationship of mycoloyl glycolipids derived from Rhodococcus sp. 4306

Novel mycoloyl glycolipids with short carbon chains were isolated and purified from Rhodococcus sp. 4306, a soil origin of Actinomycetales. Their chemical structures were identified as trehalose 6,6'-dimycolate (TDM), trehalose 6-monomycolate, glucose 6-monomycolate, mannose 6-monomycolate and fructose 6-monomycolate. The length of carbon chains and number of double bonds of mycolic acids were C(34), C(36)and C(38)saturated, monoenoic and dienoic molecular species, which were much shorter than those of Mycobacterium tuberculosis (C(78-88)monoenoic and dienoic). Among them, only TDM could induce prominent granulomatous inflammation of the lung and spleen in mice. By contrast, other mycoloyl glycolipids induced mild lesions. The small-sized TDM of Rhodococcus possessed granulomatogenic activity, however, the toxicity was much lower than that of M. tuberculosis. Rhodococcal TDM was composed of mycolic acid with the shortest carbon chains, when compared to granulomatogenic TDM of Mycobacterium, Nocardia and Rhodococcus reported previously. Our results imply that rhodococcal TDM is a pathogenetic factor similar to that of M. tuberculosis, although rhodococcal TDM exhibits low toxicity.     

Preparation of a monoclonal antibody specific for Entamoeba dispar and its ability to distinguish E. dispar from E. histolytica.

A monoclonal antibody (MAb), MAb ED17 (immunoglobulin G2a [IgG2a]), prepared against trophozoites of Entamoeba dispar SAW1734RclAR cultured monoxenically with Crithidia fasciculata, reacted with 25 of 26 isolates of E. dispar by an indirect fluorescent-antibody test. In contrast, the MAb failed to react with any of 20 isolates of E. histolytica or other enteric protozoan parasites. Western blot (immunoblot) analysis showed that the molecular mass of the E. dispar antigen recognized by the MAb was 160 kDa under reduced conditions. Immunoelectron microscopy revealed that the antigen was mainly located on digested C. fasciculata, but not on undigested organisms. Double staining with a mixture of MAb ED17 and MAb 4G6 (an IgG1 MAb which reacts exclusively with E. histolytica), followed by incubation with a mixture of fluorescein isothiocyanate-labeled anti-mouse IgG2a and tetramethylrhodamine isothiocyanate-labeled anti-mouse IgG1 antibodies, simultaneously identified mixed populations of E. dispar and E. histolytica. This method may prove to be useful for the accurate identification of E. dispar and E. histolytica, even in mixed infections.     

Antigenic variation of the Epstein–Barr virus nuclear antigen EBNA1 as revealed by monoclonal antibodies

The Epstein–Barr virus (EBV) nuclear antigen EBNA1 plays an essential role in the replication of EBV episomes in latently infected cells and is the only viral protein that is consistently expressed in all programs of latent EBV gene expression. In this study, four monoclonal antibodies (MoAbs) directed to a region (amino acid residues 442–530) of EBNA1 were generated. Competitive enzyme-linked immunosorbent assay (ELISA) experiments using biotinylated MoAbs showed that they recognized distinct epitopes. Reactivity of these MoAbs with various laboratory EBV strains and field EBV isolates was shown to be heterogeneous in that EBNA1 from certain strains (isolates) was recognized and that from others was not. All four MoAbs showed such heterogeneous reactivity, and moreover, each MoAb showed a distinct spectrum of reactivity with these EBV strains (isolates). These results demonstrate an extensive structural variation in this region of EBNA1 as predicted by previous sequencing studies. These MoAbs will be useful as probes to dissect this structural heterogeneity of EBNA1.     

Changes in the incidence and duration of ventricular fibrillation in dependence on the extraneuronal accumulation of isoprenaline in the perfused rat heart

Summary The relationship between the accumulation of isoprenaline and the incidence and duration of ventricular fibrillation was investigated in the perfused rat heart. Isolated rat hearts were perfused with ³H-isoprenaline (1 mol/l) for 30 min at a constant flow rate of 6.5 ml/min at a temperature between 40 and 41° C. Electrocardiograms were recorded during the perfusion period and the isoprenaline content of the tissue was measured after the perfusion. The accumulation of isoprenaline was significantly increased and the duration of ventricular fibrillation was significantly prolonged by the presence of tropolone (100 mol/l). When extraneuronal uptake inhibitors such as normetanephrine (100 mol/l), 3-O-methylisoprenaline (100 mol/l) or phenoxybenzamine (1 mol/l) were added to the perfusion fluid containing ³H-isoprenaline (1 mol/l) and tropolone (100 mol/l), the accumulation of isoprenaline was sifnificantly decreased, the incidence of ventricular fibrillation was significantly reduced and the duration of ventricular fibrillation was significantly shortened. There was a significant correlation for dependence of duration of ventricular fibrillation on the isoprenaline content of rat hearts perfused with various extraneuronal uptake inhibitors in the presence of tropolone (correlation coefficient [r]=0.62, P<0.001).These results indicate that the accumulation of isoprenaline in perfused rat hearts relates to the occurrence and duration of ventricular fibrillation.This study was supported in part by a Grant-in-Aid for Scientific Research (59570980) from the Ministry of Education, Science and Culture, Japan     

How Are Indeterminate Pulmonary Nodules at Diagnosis Associated with Survival in Patients with High-Grade Osteosarcoma?

BackgroundPulmonary metastases are a poor prognostic factor in patients with osteosarcoma; however, the clinical significance of subcentimeter lung nodules and whether they represent a tumor is not fully known. Because the clinician is faced with decisions regarding biopsy, resection, or observation of lung nodules and the potential impact they have on decisions about resection of the primary tumor, this remains an area of uncertainty in patient treatment. Surgical management of the primary tumor is tailored to prognosis, and it is unclear how aggressively patients with indeterminate pulmonary nodules (IPNs), defined as nodules smaller than 1 cm at presentation, should be treated. There is a clear need to better understand the clinical importance of these nodules.Questions/purposes(1) What percentage of patients with high-grade osteosarcoma and spindle cell sarcoma of bone have IPNs at diagnosis? (2) Are IPNs at diagnosis associated with worse metastasis-free and overall survival? (3) Are there any clinical or radiologic factors associated with worse overall survival in patients with IPN?MethodsBetween 2008 and 2016, 484 patients with a first presentation of osteosarcoma or spindle cell sarcoma of bone were retrospectively identified from an institutional database. Patients with the following were excluded: treatment at another institution (6%, 27 of 484), death related to complications of neoadjuvant chemotherapy (1%, 3 of 484), Grade 1 or 2 on final pathology (4%, 21 of 484) and lack of staging chest CT available for review (0.4%, 2 of 484). All patients with abnormalities on their staging chest CT underwent imaging re-review by a senior radiology consultant and were divided into three groups for comparison: no metastases (70%, 302 of 431), IPN (16%, 68 of 431), and metastases (14%, 61 of 431) at the time of diagnosis. A random subset of CT scans was reviewed by a senior radiology registrar and there was very good agreement between the two reviewers (κ = 0.88). Demographic and oncologic variables as well as treatment details and clinical course were gleaned from a longitudinally maintained institutional database. The three groups did not differ with regard to age, gender, subtype, presence of pathological fracture, tumor site, or chemotherapy-induced necrosis. They differed according to local control strategy and tumor size, with a larger proportion of patients in the metastases group presenting with larger tumor size and undergoing nonoperative treatment. There was no differential loss to follow-up among the three groups. Two percent (6 of 302) of patients with no metastases, no patients with IPN, and 2% (1 of 61) of patients with metastases were lost to follow-up at 1 year postdiagnosis but were not known to have died. Individual treatment decisions were determined as part of a multidisciplinary conference, but in general, patients without obvious metastases received (neo)adjuvant chemotherapy and surgical resection for local control. Patients in the no metastases and IPN groups did not differ in local control strategy. For patients in the IPN group, staging CT images were inspected for IPN characteristics including number, distribution, size, location, presence of mineralization, and shape. Subsequent chest CT images were examined by the same radiologist to reevaluate known nodules for interval change in size and to identify the presence of new nodules. A random subset of chest CT scans were re-reviewed by a senior radiology resident (κ = 0.62). The association of demographic and oncologic variables with metastasis-free and overall survival was first explored using the Kaplan-Meier method (log-rank test) in univariable analyses. All variables that were statistically significant (p < 0.05) in univariable analyses were entered into Cox regression multivariable analyses.ResultsFollowing re-review of staging chest CTs, IPNs were found in 16% (68 of 431) of patients, while an additional 14% (61 of 431) of patients had lung metastases (parenchymal nodules 10 mm or larger). After controlling for potential confounding variables like local control strategy, tumor size, and chemotherapy-induced necrosis, we found that the presence of an IPN was associated with worse overall survival and a higher incidence of metastases (hazard ratio 1.9 [95% CI 1.3 to 2.8]; p = 0.001 and HR 3.6 [95% CI 2.5 to 5.2]; p < 0.001, respectively). Two-year overall survival for patients with no metastases, IPN, or metastases was 83% [95% CI 78 to 87], 65% [95% CI 52 to 75] and 45% [95% CI 32 to 57], respectively (p = 0.001). In 74% (50 of 68) of patients with IPNs, it became apparent that they were true metastatic lesions at a median of 5.3 months. Eighty-six percent (43 of 50) of these patients had disease progression by 2 years after diagnosis. In multivariable analysis, local control strategy and tumor subtype correlated with overall survival for patients with IPNs. Patients who were treated nonoperatively and who had a secondary sarcoma had worse outcomes (HR 3.6 [95% CI 1.5 to 8.3]; p = 0.003 and HR 3.4 [95% CI 1.1 to 10.0]; p = 0.03). The presence of nodule mineralization was associated with improved overall survival in the univariable analysis (87% [95% CI 39 to 98] versus 57% [95% CI 43 to 69]; p = 0.008), however, because we could not control for other factors in a multivariable analysis, the relationship between mineralization and survival could not be determined. We were unable to detect an association between any other nodule radiologic features and survival.ConclusionThe findings show that the presence of IPNs at diagnosis is associated with poorer survival of affected patients compared with those with normal staging chest CTs. IPNs noted at presentation in patients with high-grade osteosarcoma and spindle cell sarcoma of bone should be discussed with the patient and be considered when making treatment decisions. Further work is required to elucidate how the nodules should be managed.Level of EvidenceLevel III, prognostic study.     

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     

ASO Visual Abstract: Influence of Damaged Stomach on Anastomotic Leakage After Cervical Esophagogastrostomy for Patients with Esophageal Cancer

Annals of Surgical Oncology -     

Longitudinal assessment of anti-Müllerian hormone after cesarean section and influence of bilateral salpingectomy on ovarian reserve

ObjectiveThis study aimed to compare longitudinal changes in ovarian reserve markers after cesarean section (CS) with and without bilateral salpingectomy (BS).Study designWe prospectively enrolled women >35 weeks’ gestation scheduled for CS alone or CS + BS and obtained blood samples for anti-Müllerian hormone prior to surgery and at 3 and 6 months after surgery. At the 3-month visit, we similarly performed transvaginal ultrasound for antral follicle count.ResultsWe enrolled 50 women; 30 underwent CS only and 20 underwent CS + BS. Although anti-Müllerian hormone level increased over 6 months of follow-up in both groups, no clinically important differences in the geometric mean (interquartile range) (ng/mL) were observed at any timepoint (baseline [0.69 {0.36?1.21} {CS only} vs 0.49 {0.32?2.10} {CS + BS}, p = 0.64]; 3 months [1.35 {0.58?3.13} vs 1.45 {1.04?2.25}, p = 0.79]; and 6 months [1.74 {0.93?4.45} vs 2.60 {1.41?5.10}, p =0.27]). Similarly, we detected no difference in antral follicle count.ConclusionBS at the time of CS does not have a negative impact on ovarian reserve 6 months after surgery.ImplicationWhile our results provide reassuring data that bilateral salpingectomy for permanent contraception at the time of cesarean section does not impact ovarian reserve, longer adequately powered studies are needed.     

Vaccination with chimeric protein induces protection in murine model against ascariasis

An estimated 400 million people are infected by parasites of the genus Ascaris and the existing control measures are inefficient. Vaccine development using B cell antigens is a promising strategy for increased protection against this parasite. The present study aimed at developing a chimeric protein capable of conferring protection against infection by Ascaris sp. For this purpose, we performed B-cell epitope predictions on previously described vaccine candidate proteins from Ascaris suum and the corresponding peptides were used to construct a chimeric protein. Female BALB / c mice were immunized subcutaneously in three doses at 10 day intervals with a vaccine formulation comprised of the chimeric protein together with monophosphoryl lipid A (MPLA). Control groups included protein alone, MPLA, or PBS. After challenge infection, animals vaccinated with chimeric protein plus MPLA showed a reduction of 73.54% of larval load in the lung compared to control group animals. Animals immunized with chimeric protein plus MPLA also display higher IgG response and a reduction in lung inflammation. Our study highlights how chimeric proteins containing more than one B cell epitope can enhance immune protection against helminthic infection and offer new approaches to the development of Ascaris vaccines.