Quantitative evaluation of the therapeutic effects of antibiotics using silkworms infected with human pathogenic microorganisms

The injection of bacteria (Staphylococcus aureus, Stenotrophomonas maltophilia) or true fungi (Candida albicans, Candida tropicalis) that are pathogenic to humans into the silkworm hemolymph leads to death of the larvae within 2 days. Antibiotics used for clinical purposes have therapeutic effects on silkworms infected with these pathogens. The 50% effective doses obtained by injection into the silkworm hemolymph are consistent with those reported for mice. Injection of vancomycin and kanamycin into the silkworm hemolymph was effective, but oral administration was not. Chloramphenicol, which is effective by oral administration, appeared in the silkworm hemolymph soon after injection into the midgut, whereas vancomycin did not. Isolated midgut membranes were impermeable to vancomycin. Thus, the ineffectiveness of oral administration of vancomycin to silkworms is due to a lack of intestinal absorption.     

Compared effects of calcium and sodium polystyrene sulfonate on mineral and bone metabolism and volume overload in pre-dialysis patients with hyperkalemia

Background

Hyperkalemia is prevalent in end-stage renal disease patients, being involved in life-threatening arrhythmias. Although polystyrene sulfonate (PS) is commonly used for the treatment of hyperkalemia, direct comparison of effects between calcium and sodium PS (CPS and SPS) on mineral and bone metabolism has not yet been studied.

Methods

In a randomized and crossover design, 20 pre-dialysis patients with hyperkalemia (>5 mmol/l) received either oral CPS or SPS therapy for 4 weeks.

Results

After 4-week treatments, there was no significant difference of changes in serum potassium (K) from the baseline (ΔK) between the two groups. However, SPS significantly decreased serum calcium (Ca) and magnesium (Mg) and increased intact parathyroid hormone (iPTH) values, whereas CPS reduced iPTH. ΔiPTH was inversely correlated with ΔCa and ΔMg (r = ?0.53 and r = ?0.50, respectively). Furthermore, sodium (Na) and atrial natriuretic peptide (ANP) levels were significantly elevated in patients with SPS, but not with CPS, whereas ΔNa and ΔANP were significantly correlated with each other in all the patients. We also found that ΔNa and Δ(Na to chloride ratio) were positively correlated with ΔHCO₃ ^?. In artificial colon fluid, CPS increased Ca and decreased Na. Furthermore, SPS greatly reduced K, Mg, and NH₃.

Conclusion

Compared with SPS, CPS may be safer for the treatment of hyperkalemia in pre-dialysis patients, because it did not induce hyperparathyroidism or volume overload.

     

Histogenesis of metaplastic breast carcinoma and axillary nodal metastases

A 40-year-old breast-feeding woman presented with left breast swelling. On physical examination a 7 cm mass was found in the breast. Because biopsy demonstrated malignant tissue, mastectomy with axillary nodal dissection was performed. Pathological findings were consistent with metaplastic breast carcinoma with nodal metastases. The primary tumor consisted of three types of invasion: ductal, squamous, and sarcomatous. Furthermore, three morphological transitions were observed: ductal–squamous, ductal–sarcomatous, and squamous–sarcomatous. Ductal–squamous (12/18 microscopy slides) and squamous–sarcomatous transitions (10/18) were more commonly observed than ductal–sarcomatous transition (3/18). Furthermore, immunohistochemistry showed loss of epithelial marker (cytokeratin) and acquisition of mesenchymal markers (vimentin and α-smooth muscle actin) in the sarcomatous component. These findings suggested that epithelial–mesenchymal transition had occurred in the tumor and that two pathways, ductal–squamous–sarcomatous and ductal–sarcomatous transition, were involved in progression of metaplastic breast carcinoma. The main pathway appeared to be ductal–squamous–sarcomatous transition. Regarding the nodal metastases, of 13 positive nodes, ductal, squamous, and sarcomatous components were observed in 13, seven, and two nodes, respectively. Moreover, as in the primary tumor, ductal–squamous and squamous–sarcomatous transitions were observed. This suggested that the ductal component metastasized to the nodes and that epithelial–mesenchymal transition subsequently occurred within the nodes.     

Enzymatic properties and localization of motopsin (PRSS12), a protease whose absence causes mental retardation

Motopsin (PRSS12) is a mosaic protease expressed in the central nervous system. Truncation of the human motopsin gene causes nonsyndromic mental retardation. Understanding the enzymatic properties and localization of motopsin protein in the central nervous system will help identify the molecular mechanism by which the loss of motopsin function causes mental retardation. Recombinant motopsin showed amidolytic activity against the synthetic substrate benzyloxycarbonyl-l-phenylalanyl-l-arginine 4-methyl-coumaryl-7-amide. Motopsin activated the single-chain tissue plasminogen activator precursor and exhibited gelatinolytic activity. This enzymatic activity was inhibited by typical serine protease inhibitors such as aprotinin, leupeptin, and (4-amidinophenyl) methanesulfonyl fluoride. Immunocytochemistry using anti-motopsin IgG revealed that both human and mouse motopsin proteins were distributed in discrete puncta along the dendrites and soma as well as axons in cultured hippocampal neurons. In the limbic system, including the cingulate and hippocampal pyramidal neurons and piriform cortex, high level of motopsin protein was expressed at postnatal day 10, but a very low level at 10-week-old mice. Motopsin and tissue plasminogen activator were co-expressed in the cingulate pyramidal neurons at postnatal day 10 and were distributed along dendrites of cultured pyramidal neurons. In cranial nuclei, a moderate level of motopsin protein was detected independently on the developmental stage. Our results suggest that motopsin has multiple functions, such as axon outgrowth, arranging perineuronal environment, and maintaining neuronal plasticity, partly in coordination with other proteases including tissue plasminogen activator.     

Ectopic pleural thymoma presenting as a giant mass in the thoracic cavity

We describe a rare case of a giant thymoma that developed in the right thoracic cavity, and seemed to originate from the visceral pleura. We believe that there have been few reports of thymoma developing from such an unusual origin.     

Weekly paclitaxel therapy is curative for patients with retroperitoneal liposarcoma

In March 2004, we resected a giant retroperitoneal liposarcoma and the transverse colon, spleen and left kidney in a 58-year-old woman. In July, recurrence was detected in the right pelvis and left upper abdomen; therefore, we resected the tumor. In September 2004, computed tomography (CT) revealed multiple recurrences in the right lower abdomen, left upper abdomen, front of the left lobe of the liver, and at the back of the stomach. In October 2004, we started mesna, doxorubicin, ifosfamide, and dacarbazine therapy (MAID); however, after 1 course, the disease progressed, and the patient developed edema in the bilateral legs due to inferior vena cava (IVC) compression. In November 2004, we started weekly paclitaxel therapy (100 mg/m(2), once a week for 3 weeks followed by 1 drug-free week). CT revealed no change as a result of chemotherapy; however, IVC compression had improved, and leg edema had decreased. In August 2005, chemotherapy was stopped; therefore,the patient's condition worsened. She died in September 2005. We performed weekly paclitaxel therapy for the patient with recurrent liposarcoma. This improved her symptoms and quality of life (QOL). Therefore,we consider weekly paclitaxel therapy to be effective for liposarcoma treatment.     

Relationship between the loss of heterozygosity and tobacco smoking in pulmonary adenocarcinoma

A loss of heterozygosity (LOH) is a major cause of lung carcinogenesis, and it is considered to be related to tobacco smoking in central type lung cancer. We investigated the relationship between LOH in lung adenocarcinoma and tobacco smoking. In a consecutive series of 50 patients with lung adenocarcinoma who underwent a surgical resection, cancer tissue specimens and corresponding normal peripheral lung and central bronchial tissue specimens were analyzed for LOH at the regions of D3S1234 (FHIT), D3S1300 (FHIT), D9S171 (CDKN2), and D17S796 (p53) by polymerase chain reaction using four fluorescence-labeled dinucleotide markers. To examine how cells are influenced by smoking, the A549 cell line was exposed to benzo[a]pyrene (B[a]P) for 24 weeks and then was subjected to the above analysis. The LOH in cancer tissue was thus detected in four (17%) patients at D3S1234, six (14%) at D3S1300, and seven (18%) at D17S796, but no LOH was detected in any normal tissue specimens. The incidence of LOHs in cancer tissue specimens from active smokers was 21% at D3S1234, 11% at D3S1300, and 19% at D17S796, whereas that of LOHs from nonactive smokers was 0% at D3S1234, 19% at D3S1300, and 14% at D17S796. Analyzing the relationship between the pack-year index and the presence of LOH, a significant difference was found among the active smokers. Besides, in the A549 cell line exposed to B[a]P, LOH was de novo detected in one (D2S123) of the nine regions examined. The incidence of LOH could be influenced by tobacco smoking in lung adenocarcinoma, thus suggesting the presence of an important event in the carcinogenesis of this disease.     

Flavonoids from Acacia pennata and their cyclooxygenase (COX-1 and COX-2) inhibitory activities

Two new flavonoids quercetin 4'-O-alpha-L-rhamnopyranosyl-3-O-beta-D-allopyranoside (1) and apigenin 6-C-[2'-O-(E)-feruloyl- beta-D-glucopyranosyl]-8-C-beta-glucopyranoside (2), along with the known isorhamnetin 3-O-alpha-L-rhamnopyranoside (3), kaempferol 3-O-alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranoside (4), and isovitexin (5) were isolated from the leaves of Acacia pennata Willd. (Mimosaceae) and tested for their anti-inflammatory activity. Their structures were determined by 1D and 2D NMR and mass spectrometry. They were tested for an inhibitory effect on COX-1 and COX-2, showing 60-90% inhibition at 10(-4) g/mL and 5-14% inhibition at 10(-4) g/mL, respectively.     

Ophthalmic Artery Flow Pattern-related Stump Pressure and Ischemic Tolerance during Balloon Test Occlusion of the Internal Carotid Artery

Very few studies have described the blood flow pattern in the ipsilateral ophthalmic artery (OphA) during internal carotid artery (ICA) balloon test occlusion performed to estimate the risk of cerebral ischemia associated with therapeutic ICA sacrifice. This study aimed to investigate the relationship between ipsilateral OphA flow patterns just after ICA temporary occlusion and balloon test occlusion findings. We retrospectively reviewed 32 balloon test occlusion procedures performed at our institution between 2010 and 2019, and analyzed the OphA flow patterns and the conventional balloon test occlusion assessment items: neurological symptoms, stump pressure, stump-pressure ratio, collateral circulations, and venous phase delay. The flow patterns were categorized as type I (retrograde flow reaching the middle cerebral artery [MCA]), type II (retrograde flow to the ICA not reaching the MCA), or type III (no retrograde flow). Tolerance to balloon test occlusion was observed in 4/21 patients (19.0%), 4/6 patients (66.7%), and all five patients with types I, II, and III flows, respectively. The mean pressure ratios during balloon test occlusion in flow types I, II, and III were 35.6% ± 3.5%, 56.4% ± 6.5%, and 69.4% ± 7.1%, respectively (P <0.001). The mean stump pressures in flow types I, II, and III were 36.2 ± 3.6 mmHg, 46.6 ± 6.7 mmHg, and 66.6 ± 7.3 mmHg, respectively (P = 0.003). The mean venous phase delay in flow types I, II, and III were 0.99 ± 0.14 s, 0.25 ± 0.25 s, and 0.0 ± 0.28 s, respectively (P = 0.004). All the above variables showed significant flow-related differences. These results suggest that the OphA flow patterns may provide an additional diagnostic criterion for balloon test occlusion.     

Level, distribution and correlates of platelet-derived microparticles in healthy individuals with special reference to the metabolic syndrome

Platelet-derived microparticles (PDMPs), a procoagulant factor, are reportedly elevated in type 2 diabetes mellitus and acute coronary syndrome. The metabolic syndrome (MS) is strongly associated with cardio- and cerebrovascular disease-related atherothrombotic events. To clarify the level, distribution and correlates of PDMPs with special reference to MS, we conducted a cross-sectional study of 467 healthy Japanese volunteers without signs, symptoms, or a history of cardio- or cerebrovascular disease. They were 211 men and 256 women (median age 39 and 35 years, respectively). Using an ELISA kit and monoclonal antibodies against CD42b and CD42a (glycoprotein Ib and IX) we assayed the PDMP levels. Total cholesterol, low-density and high-density lipoprotein cholesterol, remnant cholesterol, triglycerides, C-reactive protein, and traditional cardiovascular risk factors were also recorded. There was a significant difference in the level of PDMPs between men and women. The median value and the interquartile range of PDMPs was 8.3 IU/ml and 6.2-10.5 IU/ml and 6.8 IU/ml and 5.2-8.6 IU/ml, respectively, in men and women. PDMPs were significantly associated with MS criteria in men (p < 0.001) and women (p = 0.040). Logistic regression analysis revealed a significant odds ratio of 3.9 [95% confidence interval (CI): 1.4-10.5] in men and of 4.2 [95% CI: 1.6-10.7] in the entire study population. Our results suggest that PDMPs identified by glycoprotein CD42b and CD42a are positively associated with MS.