Laparoscopic excision of a retroperitoneal schwannoma: A case report

Schwannomas are tumors originating from the Schwann cells of the peripheral nerve sheath. Only 1%–3% of schwannomas reportedly occur in the pelvis. In a 67‐year‐old man, a pelvic mass that was 52 mm in diameter was incidentally diagnosed during a preoperative CT evaluation for prostate cancer. Preoperative 3‐D reconstruction CT showed that the feeding artery to the tumor originated from the internal iliac artery and the drainage vein from the internal iliac vein. Each vessel could be isolated, clipped, and cut with minimal bleeding. The tumor was easily dissected from adjacent structures and was completely resected via laparoscopic surgery. Histopathology and immunohistochemistry of the excised specimen revealed a benign schwannoma. Using 3‐D reconstruction to recognize a tumor's positional relation with the supplying vessels is important for avoiding complications during laparoscopic resection in the narrow pelvis. Laparoscopic resection is safe, feasible, and effective for retroperitoneal schwannoma.     

Preparation of glycoside polymer micelles with antioxidant polyphenolic cores using alkylated poly(arbutin)s

This paper describes the synthesis of long-chain-alkylated poly(arbutin)s (poly(Arb)-R_x, where R = alkyl-chain length and x = degree of substitution (DS)) and their aqueous micelle formation. DS was controlled by tailoring the alkyl reagent/main-chain phenol substituent feed ratio. The critical micelle concentrations (CMCs) of poly(Arb)-R_x were determined as 1.3–5.2 mg mL⁻¹ by the surface tension method. Introduction of longer alkyl substituents decreased CMC and also decreased aqueous solubility. In DLS measurement, the average micelle diameters were 225–616 nm, and micelle size decreased with increasing DS because of increased stabilization by hydrophobic alkyl substituents. Transmission electron microscopy indicated that mainly wormlike cylindrical micelles were formed, even with highly hydrophilic polymers. The alkylated polymer exhibited no cytotoxicity, and their antioxidant abilities were evaluated by the β-carotene bleaching method. Only 0.049 mol equivalents of poly(Arb)-C8₃₀ to linoleic acid was sufficient to preserve the β-carotene.

This paper describes the synthesis of long-chain-alkylated poly(arbutin)s (poly(Arb)-R_x, where R = alkyl-chain length and x = degree of substitution (DS)) and their aqueous micelle formation.     

Efficacy and safety of cefditoren pivoxil for exacerbations of chronic obstructive pulmonary disease: A prospective multicenter interventional study

Oral antibiotic therapy for patients with acute exacerbations of chronic obstructive pulmonary disease (COPD) usually involves an aminopenicillin with clavulanic acid, a macrolide, or a quinolone. To date, however, the clinical efficacy and safety of the oral cephalosporin cefditoren pivoxil has not been evaluated in Japanese patients with acute exacerbations of COPD. We conducted a prospective, multicenter, single arm, interventional study from January 2013 to March 2017 to determine the efficacy and safety of oral administration of 200 mg cefditoren pivoxil three times daily for 7 days in a cohort of 29 eligible patients from 15 hospitals. The mean age (SD) of participants was 73.1 (8.1) years and 28 had a smoking history (the mean [SD] of smoking index, 1426.7 [931.7]). The primary efficacy endpoint was clinical response (cure rate) at test of cure, which was set at 5–10 days after treatment ceased. Of the 23 patients finally analyzed, cure was achieved in 15 (65.2%), while 8 (34.8%) remained uncured. Previous experience of acute exacerbations significantly affected the cure rate: none of the three patients who had at least two prior exacerbations were cured, while 15 of the 20 patients with one or fewer prior exacerbations were cured (p = 0.032). The microbiological eradication rate was 88.9% at test of cure. During treatment, mild pneumonia was reported as an adverse event in one patient (3.4%) but resolved within 10 days of onset. We conclude that cefditoren pivoxil represents a viable alternative for antibiotic therapy in patients with few prior exacerbations.     

Adenocarcinoma arising from gastric duplication: a case report with literature review

Gastric duplication is a rare congenital malformation. We report the case of a 50-year-old man with adenocarcinoma derived from gastric duplication. He was referred to our institute because of persistent vomiting due to pyloric stenosis. Abdominal computed tomography revealed two cystic lesions: a 2-cm mass located along the greater curvature of the upper gastric corpus and a 3-cm mass adjacent to the bulbus. Under the diagnosis of gastric duplication cysts, the oral cyst was removed with the gastric wall and the other cyst lesion firmly adhered to the bulbus was treated with distal gastrectomy. Based on histological findings showing adenocarcinoma in the anal duplication cyst wall and regional lymph node metastases and cancer invasion into the duodenal stump, pancreatoduodenectomy was performed 9 days after the initial surgery. Invasion into the pancreas head and duodenal walls was seen in the resected specimen. Although the postoperative course was uneventful, he died of local recurrence and multiple liver metastases 14 months after surgical treatment. This case report with literature review indicates that alimentary tract duplication cysts should be recognized as risky lesions of cancer development in patients aged 50 years or over.     

Efficient Isolation of Swine Influenza Viruses by Age-Targeted Specimen Collection

The control of swine influenza virus (SIV) infection is paramount for increasing the productivity of pig farming and minimizing the threat of pandemic outbreaks. Thus, SIV surveillance should be conducted by region and on a regular basis. Here, we established a microneutralization assay specific for SIV seroprevalence surveillance by using reporter gene-expressing recombinant influenza viruses. Growth-based SIV seroprevalence revealed that most sows and piglets were positive for neutralizing antibodies against influenza viruses. In contrast, the 90-day-old growing pigs exhibited limited neutralizing activity in their sera, suggesting that this particular age of population is most susceptible to SIV infection and thus is an ideal age group for SIV isolation. From nasal swab specimens of healthy pigs in this age population, we were able to isolate SIVs at a higher incidence (5.3%) than those of previous reports. Nucleotide sequencing and phylogenetic analysis of the hemagglutinin (HA) genes revealed that the isolated SIVs have circulated and evolved in pigs but not have been recently introduced from humans, implying that a large number of SIV lineages may remain “undiscovered” in the global porcine populations. We propose that the 90-day-old growing pig-targeted nasal swab collection presented in this study facilitates global SIV surveillance and contributes to the detection and control of SIV infection.     

Capsule Switching and Antimicrobial Resistance Acquired during Repeated Streptococcus pneumoniae Pneumonia Episodes

Streptococcus pneumoniae colonizes the nasopharyngeal mucus in healthy people and causes otitis media, pneumonia, bacteremia, and meningitis. In this study, we analyzed an S. pneumoniae strain that caused 7 repeated pneumonia episodes in an 80-month-old patient with cerebral palsy during a period of 25 months. A total of 10 S. pneumoniae strains were obtained from sputum samples, and serotype 6B was isolated from samples from the first 5 episodes, whereas serotype 6A was isolated from samples from the last 2. Whole-genome sequencing showed clonality of the 10 isolates with 10 single nucleotide polymorphisms (SNPs) in the genomes. Among these SNPs, one single point mutation in the wciP gene was presumed to relate to the serotype switching from 6B to 6A, and the other mutations in parC and gyrA were related to fluoroquinolone resistance. These results suggested that an S. pneumoniae strain, which asymptomatically colonized the patient''s nasopharynx or was horizontally transmitted from an asymptomatic carrier, caused the repeated pneumonia events. Phenotypic variations in the capsule type and antimicrobial susceptibility occurred during the carrier state. Hyporesponsiveness to serotypes 6B and 6A of S. pneumoniae was found even after vaccination with the 7-valent pneumococcal conjugate vaccine and the 23-valent pneumococcal polysaccharide vaccine. After an additional vaccination with the 13-valent pneumococcal conjugate vaccine, opsonic activities for both serotypes 6A and 6B significantly increased and are expected to prevent relapse by the same strain.     

Detection of active schistosome infection by cell-free circulating DNA of Schistosoma japonicum in highly endemic areas in Sorsogon Province,the Philippines

The current status of schistosomiasis in highly endemic areas is difficult to determine by ovum detection because of the superficially low parasite load after mass drug administration, whereas the parasite transmission rates are still high. Cell-free parasite DNA is fragments of parasite-derived DNA existing in the host's body fluids. We conducted population-based studies to test the presence of cell-free schistosome DNA in endemic areas of Sorsogon Province, the Philippines. Schistosome DNA in the serum and urine of Kato–Katz (KK)-positive subjects was detected by PCR (100% sensitivity). Schistosome DNA was also detected from KK-negative subjects (9/22 serum and 10/41 urine samples). Schistosome DNA was found to be network echogenic pattern (NW)-positive (serum 53.3%, urine 42.9%) or NW-negative (serum 25.5%, urine 20.8%) and enzyme-linked immunosorbent assay (ELISA)-positive (serum 47.1%, urine 40%) or ELISA-negative (serum 33.3%, urine 13.3%). These results indicate that cell-free schistosome DNA is a promising diagnostic marker for active schistosome infection in the case of light infection.     

Low frequency of PAX8‐PPARγ rearrangement in follicular thyroid carcinomas in Japanese patients

Paired‐box gene 8 (PAX8)‐peroxisome proliferator‐activated receptor‐γ (PPARγ) gene fusion has been identified at significant frequency in follicular thyroid carcinomas (FTCs) with cytogenetically detectable translocation t(2;3)(q13;p25). This represents a possible specific molecular marker for follicular carcinoma. In this study, we examined PAX8‐PPARγ rearrangement in 24 FTC samples from Japanese patients by reverse transcribed‐polymerase chain reaction (RT‐PCR) using two upstream PAX8 primers located in exons 7 and 8 and a downstream primer in exon 1 of PPARγ. The fusion gene was detected in only one of 24 FTCs (4%). The FTC with PAX8‐PPARγ rearrangement from a 56‐year‐old man showed a product consistent with fusion between exon 8 of PAX8 and exon 1 of PPARγ. It was confirmed by direct sequencing. This FTC was histologically encapsulated, composed of trabeculae and small follicles and had complete penetration of the capsule by tumor tissues (minimally invasive type). The frequency of the fusion gene in this study was much lower than the 29–63% noted in reports from other countries suggesting that FTCs in Japanese patients may have a special genetic background, and that the high iodine intake from a typical Japanese diet might influence the frequency of the fusion gene in FTCs.