Interruption of pulmonary arterial flow with inadequate ventilation leads to pulmonary infarction

We examined the effect of interruption of pulmonary arterial flow and inadequate ventilation on the development of pulmonary infarction in rats. Pulmonary arterial flow was blocked by the injection of agar into the inferior vena cava and inadequate ventilation was produced by obstructing the left main bronchus with a polypropylene tip. Histological and angiographic examination of the lung demonstrated that: pulmonary artery embolism alone does not induce pulmonary infarction; obstruction of a bronchus does not induce significant changes, but that pulmonary infarction develops when pulmonary artery embolism and obstruction of a bronchus occur simultaneously. It has been thought that pulmonary infarction is caused by acute obstruction of a pulmonary artery, however, the alveolar walls are supplied with oxygen by both the pulmonary circulation and by ventilation. Interruption of pulmonary arterial flow alone is probably not sufficient to induce pulmonary infarction, which is probably caused by deficiency of oxygen supply to the alveolar walls by a synergy between interruption of pulmonary arterial flow and inadequate ventilation.     

Vipoma of the Pancreas Complicating Ulcerative Colitis

We report a case of vipoma of the pancreas in conjunction with ulcerative colitis in a 20-yr-old woman. Twenty months after the onset of ulcerative colitis, the patient complained of watery diarrhea and was found to have an electrolyte disorder. A pancreatic tumor was detected by ultrasonography and computed tomography, along with an elevation of serum vasoactive intestinal polypeptide (VIP). The secretory diarrhea diminished dramatically, and the serum VIP level decreased into the normal range immediately after resection of the pancreatic tumor. Immunohistochemical staining revealed a pancreatic vipoma. Despite removal of the vipoma, she underwent restorative proctocolectomy and ileal J-pouch anal anastomosis 2 yr later due to progression of the ulcerative colitis. Postoperative course was uneventful, with excellent functional results. Knowledge of this rare condition accompanying ulcerative colitis may help in the management of the patient with an atypical clinical course.     

Creation of Straight-Chain Cationic Polysaccharide-Based Bile Salt Sequestrants Made from Euglenoid β-1,3-Glucan as Potential Antidiabetic Agents

Purpose

The objective of this work was to evaluate the potential of polymeric spherical and aspherical invasive nanocarriers, loaded with antibiotic, to access and treat intracellular bacterial infections.

Methods

Aspherical nanocarriers were prepared by stretching of spherical precursors, and both aspherical and spherical nanocarriers were surface-functionalized with the invasive protein InvA497. The relative uptake of nanocarriers into HEp-2 epithelial cells was then assessed. Nanocarriers were subsequently loaded with a preparation of the non-permeable antibiotic gentamicin, and tested for their ability to treat HEp-2 cells infected with the enteroinvasive bacterium Shigella flexneri.

Results

InvA497-functionalized nanocarriers of both spherical and aspherical shape showed a significantly improved rate and extent of uptake into HEp-2 cells in comparison to non-functionalized nanocarriers. Functionalized and antibiotic-loaded nanocarriers demonstrated a dose dependent killing of intracellular S. flexneri. A slight but significant enhancement of intracellular bacterial killing was also observed with aspherical as compared to spherical functionalized nanocarriers at the highest tested concentration.

Conclusions

InvA497-functionalized, polymer-based nanocarriers were able to efficiently deliver a non-permeable antibiotic across host cell membranes to affect killing of intracellular bacteria. Functionalized nanocarriers with an aspherical shape showed an interesting future potential for intracellular infection therapy.

     

Huntingtin-interacting protein-1-related protein of rat (rHIP1R) is localized in the postsynaptic regions

We cloned a rHIP1R (GenBank Accession No., AB005052) encoding a Sla2/huntingtin-interacting protein (HIP1) family protein from a rat brain cDNA library. Localization of rHIP1R was investigated in the rat brain using an antibody specific to the HIP1R antibody. The rHIP1R protein was enriched in the synaptic plasma membrane fraction along with huntingtin, a synaptic protein and a causal protein for Huntington's disease. The electron microscopic examination revealed that HIP1R was localized at postsynaptic spines. Localization of HIP1R in the small vesicular structures in the spine, possible sites of vesicular transport of synaptic proteins, together with the structure-based analysis, suggested a role of HIP1R for vesicle trafficking through interaction with F-actin and working together with huntingtin and HIP1 at the synaptic sites.     

A new regimen for TS-1 therapy designed to minimize adverse reactions by introducing a one-week interval after each two-week dosing session

It has been reported that the response rate to TS-1 of advanced recurrent gastric cancer was the highest rate (46.5%) of effectiveness among anti-cancer agents, but the incidence of adverse reactions to this drug has been found to be as high as 83.2%, with grade 3 or severer reactions occurring in 20.3% of patients. Taking into consideration the post-marketing survey finding that adverse reactions to the drug first appear 2-3 weeks after the start of oral TS-1 therapy, we attempted a new dosing regimen for this drug, wherein each session of therapy lasted for 2 weeks, with a one-week interval between two consecutive sessions (herein-after called "the 2-week regimen"). This regimen was employed based on the expectation that the adverse reactions to the drug would be minimized and that the consecutive dosing period could be prolonged, while keeping the anti-cancer potency at a level similar to that expected with the 4-week dosing regimen with a 2-week interval between sessions (the 4-week regimen). The subjects were 38 patients with advanced or recurrent stomach cancer who were treated with TS-1 at our center between September 1999 and November 2001. Twenty-four patients treated using the 4-week method until January 2001 were taken as a historical control, and compared with 14 patients treated using the 2-week method from February 2001 and afterwards. The incidence of adverse reactions was 71% in the 2-week regimen group against 92% in the 4-week regimen group. The incidence of grade 3 or severe adverse reactions was 8% in the 2-week group and 21% in the 4-week group. Thus, the incidence of adverse reactions was lower in the 2-week group. The percentage of patients who complied with the dosing instructions completely during a 6-month period, as evaluated by the Kaplan-Meier method, was 86% in the 2-week group and 58% in the 4-week group. The response rate, as calculated in patients whose lesions could be evaluated, was 25% in the 2-week group and 19% in the 4-week group. These results suggest that the 2-week regimen may allow safer outpatient drug therapy using TS-1 and merits a trial when considering the QOL of patients. We propose conducting a phase-II multi-center clinical study of this regimen in the near future.     

A novel scaffold protein, TANC, possibly a rat homolog of Drosophila rolling pebbles (rols), forms a multiprotein complex with various postsynaptic density proteins

We cloned from the rat brain a novel gene, tanc (GenBank Accession No. AB098072), which encoded a protein containing three tetratricopeptide repeats (TPRs), ten ankyrin repeats and a coiled-coil region, and is possibly a rat homolog of Drosophila rolling pebbles (rols). The tanc gene was expressed widely in the adult rat brain. Subcellular distribution, immunohistochemical study of the brain and immunocytochemical studies of cultured neuronal cells indicated the postsynaptic localization of TANC protein of 200 kDa. Pull-down experiments showed that TANC protein bound PSD-95, SAP97, and Homer via its C-terminal PDZ-binding motif, -ESNV, and fodrin via both its ankyrin repeats and the TPRs together with the coiled-coil domain. TANC also bound the alpha subunit of Ca2+/calmodulin-dependent protein kinase II. An immunoprecipitation study showed TANC association with various postsynaptic proteins, including guanylate kinase-associated protein (GKAP), alpha-internexin, and N-methyl-D-aspartate (NMDA)-type glutamate receptor 2B and AMPA-type glutamate receptor (GluR1) subunits. These results suggest that TANC protein may work as a postsynaptic scaffold component by forming a multiprotein complex with various postsynaptic density proteins.     

Expression of adhesion molecules by sphingosine 1-phosphate and histamine in endothelial cells

We investigated the effects of sphingosine 1-phosphate and histamine on the expression of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and E-selectin, and their signaling pathways in human umbilical vein endothelial cells. Sphingosine 1-phosphate increased the mRNA and protein level of VCAM-1, and the mRNAs of E-selectin and ICAM-1. The effects of sphingosine 1-phosphate were inhibited by the pertussis toxin and the respective inhibitors (10 μM 1-[6-[[(17β)-3-methoxyestra-1,3,5(10)-trien-17-yl]amino]hexyl]-1H-pyrrole-2,5-dione (U73122) for phosphoinositide-specific phospholipase C; 10 μM 4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)-1H-imidazole (SB203580) for p38 mitogen-activated protein kinase (MAPK); 1 μM 12-(2-cyanoethyl)-6,7,12,13-tetrahydro-13-methyl-5-oxo-5H-indolo(2,3-a)pyrrolo(3,4-c)-carbazole (Gö6976) for the α form of protein kinase C (PKC-α)), but not by a PKC-δ inhibitor (1 μM rottlerin). Histamine, which alone showed no effect, enhanced the sphingosine 1-phosphate-induced expressions via histamine H₁ receptor. The histamine response decreased by U73122 and rottlerin, but not by SB203580 and Gö6976. The effects of sphingosine 1-phosphate with and without histamine were abolished by the higher concentrations of PKC inhibitors and in the PKC-depleted cells. Sphingosine 1-phosphate and histamine alone stimulated phosphorylation of p38 MAPK in a phosphoinositide-specific phospholipase C-dependent but not in a PKCs-independent manner. These findings suggest that sphingosine 1-phosphate-induced expression of adhesion molecules was mediated by phosphoinositide-specific phospholipase C and preferentially by PKC-α and p38 MAPK, and the histamine response was mediated by phosphoinositide-specific phospholipase C and PKC-δ in human umbilical vein endothelial cells.     

Possible role of interleukin-6 in PC12 cell death induced by MPP+ and tetrahydroisoquinoline

Interleukin (IL)-6 has been shown to protect neuronal cells from cell death induced by various stimulants. Although neuronal cells including PC12 cells were shown to produce IL-6, little is known about the effects of dopaminergic neurotoxins, 1,2,3,4-tetrahydroisoquinoline (TIQ) and 1-methyl-4-phenylpyridinium ion (MPP(+)), on IL-6 expression in PC12 cells. In the present study, we investigated the role of IL-6 in the TIQ- and MPP(+)-induced cell death in PC12 cells. Treatment with 3.2 mM TIQ for 24 h caused a delayed cell death (lactate dehydrogenase (LDH) leakage and nuclear DNA fragmentation) markedly 72 h after the addition. Addition of 0.4 mM MPP(+) caused LDH leakage and nuclear DNA fragmentation 24 h after the addition. The cell death induced by MPP(+) was inhibited by an inhibitor of caspases, z-Val-Ala-Asp(OMe)-fluoromethylketone. The cell death induced by TIQ or MPP(+) was inhibited by nerve growth factor and 10% serum and significantly enhanced by the treatment with anti-IL-6 antibody. Both neurotoxins decreased the IL-6 mRNA level in PC12 cells without changing the other tested mRNA levels (IL-1 alpha, beta-actin, etc.). These findings suggest that dopaminergic neurotoxins cause cell death in PC12 cells at least partially by changing IL-6 expression.     

TS-1 and lentinan combination immunochemotherapy for advanced or recurrent gastric cancer: a preliminary report

The immunocompetence and nutritional state of patients with advanced or recurrent gastric cancer is low, making it important to conduct chemotherapy while at the same time improving or maintaining their immunocompetence and nutritional state. To reduce the side effects but not the antitumor effect of TS-1, a 2-week regime of TS-1, and 1-week drug-free interval, in combination with the immunotherapeutic agent lentinan (LNT) was started in 5 patients with advanced or recurrent gastric cancer. Toxicity, efficacy, immunocompetence and nutritional state were investigated preliminarily to examine whether or not usefulness of lentinan could be evaluated. The IAP tended to decrease. TS-1 and lentinan combination immunochemotherapy was able to be carried out safely in patients with advanced recurrent gastric cancer. In order to examine the usefulness of combined LNT, it is thought to be necessary to perform a randomized trial using toxicity and not only efficacy but QOL and immunological and nutritional parameters as indicators.     

A new regimen for S-1 therapy aiming at adverse reaction mitigation and prolonged medication by introducing a 1-week drug-free interval after each 2-week dosing session: efficacy and feasibility in clinical practice

Background

The response rate of advanced or recurrent gastric cancer to S-1 (TS-1^®) is 46.5%, which is higher than the response rate of this type of cancer to any other anticancer agent. However, the incidence of adverse reactions to this drug has also been reported to be as high as 83.2%. According to a postmarketing survey, adverse reactions to this drug begin to appear 2–3 weeks after the start of drug administration. With these findings in mind, we recently devised a new dosing regimen for the drug, by which the drug is administered for 2-week periods separated by 1-week drug-free intervals (the 2-week regimen). The aim of this retrospective study was to evaluate the efficacy and feasibility of the 2-week regimen in comparison with a 4-week dosing regimen with a 2-week interval between sessions (the 4-week regimen) as the historical control.

Methods

The subjects were 27 patients with advanced or recurrent gastric cancer who received S-1 therapy at our center between September 1999 and November 2001. Of these patients, 14 who received the 4-week regimen before January 2001 served as historical controls, and the results in these patients were compared with those of the remaining 13 patients, who received the 2-week regimen after February 2001. Patient backgrounds, adverse reactions, compliance, and efficacy were investigated retrospectively.

Results

The incidence of adverse reactions tended to be lower in the 2-week-regimen group (77%) than in the 4-week-regimen group (93%). The percentage of patients who received the drug for 6 months in complete compliance with the dosing schedule, as calculated by the Kaplan-Meier method, was 85% in the 2-week-regimen group and 40% in the 4-week-regimen group. The response rate to the drug was 23% in the 2-week-regimen group and 21% in the 4-week-regimen group.

Conclusion

These results suggest that this 2-week regimen may mitigate adverse reactions and prolong the medication period.