Oral Iron Absorption of Ferric Citrate Hydrate and Hepcidin-25 in Hemodialysis Patients: A Prospective, Multicenter, Observational Riona-Oral Iron Absorption Trial

Oral ferric citrate hydrate (FCH) is effective for iron deficiencies in hemodialysis patients; however, how iron balance in the body affects iron absorption in the intestinal tract remains unclear. This prospective observational study (Riona-Oral Iron Absorption Trial, R-OIAT, UMIN 000031406) was conducted at 42 hemodialysis centers in Japan, wherein 268 hemodialysis patients without inflammation were enrolled and treated with a fixed amount of FCH for 6 months. We assessed the predictive value of hepcidin-25 for iron absorption and iron shift between ferritin (FTN) and red blood cells (RBCs) following FCH therapy. Serum iron changes at 2 h (ΔFe2h) after FCH ingestion were evaluated as iron absorption. The primary outcome was the quantitative delineation of iron variables with respect to ΔFe2h, and the secondary outcome was the description of the predictors of the body's iron balance. Generalized estimating equations (GEEs) were used to identify the determinants of iron absorption during each phase of FCH treatment. ΔFe2h increased when hepcidin-25 and TSAT decreased (-0.459, -0.643 to -0.276, p = 0.000; -0.648, -1.099 to -0.197, p = 0.005, respectively) in GEEs. FTN increased when RBCs decreased (-1.392, -1.749 to -1.035, p = 0.000) and hepcidin-25 increased (0.297, 0.239 to 0.355, p = 0.000). Limiting erythropoiesis to maintain hemoglobin levels induces RBC reduction in hemodialysis patients, resulting in increased hepcidin-25 and FTN levels. Hepcidin-25 production may prompt an iron shift from RBC iron to FTN iron, inhibiting iron absorption even with continued FCH intake.

Background model for the NaI(Tl) crystals in COSINE-100

The COSINE-100 dark matter search experiment is an array of NaI(Tl) crystal detectors located in the Yangyang Underground Laboratory (Y2L). To understand measured backgrounds in the NaI(Tl) crystals we have performed Monte Carlo simulations using the Geant4 toolkit and developed background models for each crystal that consider contributions from both internal and external sources, including cosmogenic nuclides. The background models are based on comparisons of measurement data with Monte Carlo simulations that are guided by a campaign of material assays and are used to evaluate backgrounds and identify their sources. The average background level for the six crystals (70 kg total mass) that are studied is 3.5 counts/day/keV/kg in the (2-6) keV energy interval. The dominant contributors in this energy region are found to be 210 Pb and 3 H.

ASXL1 and DNMT3A mutation in a cytogenetically normal B3 thymoma

The molecular drivers of thymoma are poorly understood. Outside of the identification of rarely occurring epidermal growth factor receptor and v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog mutations via candidate gene sequencing, mutations in common cancer genes have yet to be observed. Only a single thymoma genome sequence has been previously reported, with no mutations in known cancer genes identified. Thus, we attempted to identify somatic driver mutations in a cytogenetically normal thymoma. A stage IVB type B3 thymoma from a 47-year-old male of Asian descent with no history of myasthenia gravis or other autoimmune condition was genomically evaluated. Exome sequencing and low-pass whole-genome sequencing was performed to identify somatic point mutations, copy number changes and structural variants. Mutations in known tumor suppressors DNMT3A (p.G728D) and ASXL1 (p.E657fs), consistent with mutations of known consequence in acute myeloid leukemia, were identified. Contrary to a previous report, this finding suggests the genetic etiology of thymomas may not be fundamentally distinct from other tumor types. Rather, these findings suggest that further sequencing of cytogenetically normal thymoma samples should reveal the specific molecular drivers of thymoma.

In vitro contraction of the canine corpus cavernosum penis by direct perfusion with prolactin or growth hormone

PURPOSE

It is well established that hyperprolactinemia, most typically seen in prolactinoma patients, causes hypogonadism and impotence. There seems to be a good possibility that hyperprolactinemia causes impotence, at least partially via some intrinsic property of prolactin (PRL), rather than through its suppressive effects on the hypothalamic-pituitary-gonadal testosterone dynamics. In the present investigation, we used an in vitro canine model to attempt to clarify whether direct action of PRL on the corpus cavernosum penis may lead to erectile insufficiency. Growth hormone (GH) and placental lactogen (PL), both having close structural and functional homologies to PRL, were also studied.

MATERIALS AND METHODS

Isometric tension measurement with cavernous strips was performed in the presence or absence of 10(-5) to 10(-9) M. PRL, GH, or PL in the perfusion medium. The tension change induced by the test substances was normalized relative to that induced by 120 mEq KCl.

RESULTS

Both PRL and GH produced dose-related elevations (p < 0.01) of the cavernous tension, whereas PL and thiol-cleaved PRL in comparable doses were without effect (p > 0.05). When the tension rise produced by 120 mEq KCl was taken as 100%, the maximum contractions produced by PRL and GH were 80% and 110%. The minimum effective concentration was 10(-8) to 10(-7) M. for both PRL and GH. Pretreatment with indomethacin (10(-5) M.), but not tetrodotoxin (10(-5) M., partially suppressed (p < 0.05) the effects of PRL.

CONCLUSION

These results suggest that PRL and GH directly and specifically produced contraction of the corpus cavernosum penis, resulting in erectile insufficiency, and that the effect of PRL is partially mediated by prostaglandin.

Cloning and sequence analysis of the gene encoding 3-hexulose-6-phosphate synthase from the methylotrophic bacterium, Methylomonas aminofaciens 77a, and its expression in Escherichia coli

A DNA fragment of 550 bp was specifically amplified by PCR with primers based on the N-terminal sequence of the purified 3-hexulose-6-phosphate synthase from Methylomonas aminofaciens 77a and on that of a lysyl endopeptidase-derived peptide. Using this PCR product as a probe, a gene coding for 3-hexulose-6-phosphate synthase in M. aminofaciens 77a chromosomal DNA was cloned in Escherichia coli JM109. Sequencing analysis revealed that the gene encoding 3-hexulose-6-phosphate synthase contained a 624-bp open reading frame, encoding a protein composed of 208 amino acid residues with a calculated relative molecular mass of 21,224.

Participation of vasoactive intestinal polypeptide (VIP) as a humoral mediator in the erectile response of canine corpus cavernosum penis

The ability of anti-vasoactive intestinal peptide (anti-VIP) serum to suppress the electrically induced relaxation of the corpus cavernosum was evaluated in vitro to define the role of VIP in penile erection. Strips of canine corpora cavernosa were placed in 5-ml organ chambers containing oxygenated Krebs-Ringer solution. They were stretched and fixed in place at both ends and pretreated with 2 x 10(-7)M noradrenaline (NA). NA was given to produce an optimal state of isometric smooth muscle contraction so that subsequent electrical field stimulation (EFS) could induce a good range of measurable relaxation response. This response was deemed to be an in vitro representation of penile erection. After NA treatment the cavernous tension rose markedly by 2-2.5 g; it then declined by up to 1-1.2 g upon EFS. Anti-VIP serum (1:16) or atropine sulfate (10(-6)M) was added at various time points between NA administration and EFS. When anti-VIP serum was administered, subsequent EFS-induced relaxation was attenuated by 20%-55% compared to the control EFS treatments. The degree of attenuation depended upon the frequency of EFS applied, being 20.6% +/- 4.0% at 20 Hz and 54.7% +/- 6.3% at 2 Hz. Atropine administered additionally following anti-VIP serum produced no further attenuation. However, atropine alone was capable of producing up to 23.7% +/- 3.5% attenuation. When anti-VIP serum was administered following atropine, the degree of attenuation that ensured was the sum of the attenuations produced by each of the two substances independently.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of renal liposarcoma]

A-48-year-old male was admitted to our hospital with a right renal tumor. He received radical nephrectomy immediately. Histological examination of surgical specimen revealed renal liposarcoma, which consisted of mixed type of pleomorphic and well differentiated subtypes. Multiple tumorous lesions were scattered in the renal parenchyma. He has been alive without disease for 2 years and 7 months after surgery. Only 23 cases of renal liposarcoma have been reported in Japan.

[Analysis of brain CT in 120 patients with human cysticercosis]

A study on brain CT was made in 120 patients of human cysticercosis, which is a rare disease in Japan and clinical symptoms and laboratory data for the diagnosis were also discussed. From the point of therapeutic view, we proposed a new differentiation on brain CT of human cysticercosis, which is divided into two groups according to the alive or dead parasite. Furthermore, we proposed a new type named multiple large and small cysts type on brain CT. The idea of diagnostic standard was made integrating brain CT image, clinical symptoms and laboratory data.

[Transference of antibiotics into prostatic tissues: sampling method by transurethral resection for the measurement of the concentration of antibiotics in prostatic tissue]

The transeference of two antibiotics, i.e. cefmetazole (CMZ) and fosfomycin (FOM), into prostatic tissues was examined. Prostatic tissue samples were obtained from patients with benign prostatic hyperplasia while undergoing open prostatectomy or transurethral resection of the prostate (TUR-P). 2 g of CMZ or 4 g of FOM was intravenously administered within about 10 minutes starting 1 hour before the removal or resection of the prostate, and blood samples were collected at the end of the administration and during surgery. In TUR-P, resected prostatic tissues were washed with the TUR perfusate and the antibiotic in the tissue was presumed to be released into the perfusate. The following preliminary experiments were, therefore, carried out. The removed prostate was divided into three segments, i.e. urethral region, central region and capsular region, and the CMZ or FOM level in each tissue was measured. The remaining tissues were cut into small pieces for immersion in the TUR perfusate for 10-90 minutes. The tissue fragments were removed every 10 minutes to measure the tissue concentration of CMZ or FOM. The concentration of CMZ or FOM in the prostatic tissues did not vary among the three regions, however it markedly decreased with increase in the period of immersion. This suggested that the concentration of these agents into the prostatic tissues was represented by the concentration in the tissues near the urethra obtained immediately after the start of TUR-P.(ABSTRACT TRUNCATED AT 250 WORDS)

[A case of ureteral disruption caused by a traffic accident]

Disruption of the ureter is very rarely caused by a blunt trauma, only 12 cases having been reported in Japan. A 20-year-old male suffered from a blunt abdominal trauma in a traffic accident. Although his urinalysis showed no abnormalities, a dull pain in the left flank region persisted for over a week after the injury. Under the suspicion of renal or ureteral injury, an excretory urogram (DIP) was conducted. The form of renal pelvis and calyces was almost normal on both sides, while extravasation of contrast medium was recognized around the lower pole of the left kidney. The retrograde pyelogram of the left side revealed that catheterization was possible up to 30 cm from the ureteral orifice, but the injected medium leaked into the retroperitoneal space making it impossible to visualize the left renal pelvis and calyces. An operation was performed under the diagnosis of left ureteral injury on the 19th day after trauma. The left ureter was completely disrupted 2 cm distally from the ureteropelvic junction. An end to end anastomosis of the ureter was done with 6-0 Dexon sutures. The DIP taken on the 25th day after the operation showed slight dilatation of the left pelvis and calyces. However, the renogram conducted 6 months after the operation demonstrated a normal pattern on both sides.

[A case of occult testicular tumor]

A 43-year-old male presented with a left supraclavicular mass as well as an upper abdominal mass. Biopsy of the supraclavicular mass revealed seminoma with components of both embryonal carcinoma and choriocarcinoma. Right orchiectomy was performed because physical examination showed that the left testis was normal but the right testis was slightly atrophic. The primary tumor which was approximately 1 cm in diameter was found in the right testis and histological examination revealed seminoma. When germ cell tumor is found in a region other than the gonads, either primary extragonadal germ cell tumor or occult testicular tumor is considered. To differentiate between the two, it is imperative to make careful histological exploration of the testes.

[Clinical value of testicular lymphangiography in diagnosis of retroperitoneal metastases]

Testicular lymphangiography was performed before retroperitoneal lymph node dissection in 20 patients with testicular tumor. The clinical value of testicular lymphangiography in the diagnosis of retroperitoneal metastases was evaluated retrospectively in comparison with the findings obtained by retroperitoneal lymph node dissection. In 12 patients who had no metastasis in the primary lymph nodes of the testis, testicular lymphangiography showed the lymph vessels to be diverged into 2 to 6 vessels (mean: 3.5) at the level between L2 and L4, and 4 to 10 lymph nodes (mean: 6.2) at the level between L1 and L4 were filled with contrast medium. On the other hand, in 8 patients who had metastases in the primary lymph nodes, several abnormal findings were observed in both lymph vessels and nodes, i.e., discontinuity, extravasation of contrast medium, dilatation, displacement and reflux to the distal side in the lymph vessels, and decrease in number (less than 2), non-visualization, filling defect, displacement and contrastfilling in the contralateral side in lymph nodes. Three to 5 of these abnormal findings were usually found in each case. The extravasation of contrast medium was not a finding specific to cases with lymph node metastases, because it was also found in a few cases without metastases. Testicular lymphangiography is a valuable method to detect primary lymph node metastases from testicular tumor. However, the combination of testicular and foot lymphangiography is imperative to demonstrate wide spread lymph node involvement in the retroperitoneum.