Sum Frequency Generation Spectroscopic Studies on Phase Transitions of Phospholipid Monolayers Containing Poly(ethylene oxide) Lipids at the Air−Water Interface

Vibrational sum frequency generation (SFG) spectroscopy was applied to study the phase transitions of the mixed monolayers of l-alpha-distearoyl phosphatidylethanolamine (DSPE) and DSPE covalently coupled with poly(ethylene oxide) at the amino head group (DSPE-EO(45), DSPE with 45 ethylene oxide monomers) at the air-water interface. The SFG spectra were measured for the mixed monolayers with the mole fractions of DSPE-EO(45) of 0, 1.3, 4.5, 9.0, 12.5, and 16.7% at the surface pressures of 5, 15, and 35 mN/m. The monolayer compression isotherms indicated that the mixed monolayers at 5, 15, are 35 mN/m are mainly in the so-called "pancake", "mushroom", and "brush" states, respectively. The SFG spectra in the OH stretching vibration region give rise to SFG bands near 3200 and 3400 cm(-1). The mean molecular amplitude of the former band due to the OH stretching of the "icelike" water molecules associated mainly with the hydrophilic poly(ethylene oxide) (PEO) chains, exhibits appreciable decrease on compression of the mixed monolayers from 5 to 15 mN/m. The result corroborates the model for the pancake-mushroom transition, which presumes the dissolution of the PEO chains from the air-water interface to the water subphase. Further compression of the mixed monolayers to 35 mN/m causes a slight decrease of the line amplitude, which can be explained by considering a squeezing out of water molecules from the hydrophilic groups of DSPE-EO(45) in the brush state, where the PEO chains strongly interact with each other to form a tight binding state of the hydrophilic groups. The relative intensities of the SFG bands due to the CH3 asymmetric and symmetric vibrations were used to estimate the tilt angles of the terminal methyl group of DSPE, indicating that the angle increases with increasing the mole fraction of DSPE-EO(45). The angles almost saturate at the mole fraction larger than 10%, the saturation angle being nearly 90 degrees at 5 mN/m, ca. 60 degrees at 15 mN/m, and ca. 47 degrees at 35 mN/ m. Then, the introduction of the hydrophilic PEO head group causes a large tilting of the alkyl groups of DEPE in the mixed monolayers.

Ikaros is a mutational target for lymphomagenesis in Mlh1-deficient mice

Deficiencies in DNA mismatch repair (MMR) result in replication errors within key tumor suppressor genes or oncogenes, and cause hereditary nonpolyposis colorectal cancer (HNPCC). Hematological malignancy with microsatellite instability is also associated with defective MMR, but little is known about the target genes for MMR. Here we identified Ikaros, a master transcription factor of lymphoid lineage commitment and differentiation, as a mutational target in spontaneous and radiation-induced T-cell lymphomas in Mlh1-deficient mice. Three quarters of lymphomas lacked Ikaros protein expression, which resulted from a frameshift mutation that created a stop codon. Mononucleotide repeat sequences at 1029-1034(C)6 and 1567-1572(G)6 in Ikaros were mutational hot spots with a one-base deletion occurring with a frequency of 45 and 50%, respectively. Point mutations and splicing alterations were also observed. In total, 85% of the lymphomas showed aberrations in Ikaros. The characteristic of Mlh1-deficient lymphomas is harboring of multiple mutations simultaneously in the same tumor, displaying a combination of two frameshift mutations at different repeats, frameshift and point mutations, and/or deletion mutations. This is the first report of Ikaros mutations coupled with Mlh1 deficiency in lymphomagenesis.

Intracellular-diced dsRNA has enhanced efficacy for silencing HCV RNA and overcomes variation in the viral genotype

RNA interference (RNAi) can be used to inhibit viral replication in mammalian cells and therefore could be a powerful new antiviral therapy. Small interfering RNA (siRNA) may be effective for RNAi, but there are some technical problems that must be solved in each case, for example, predicting the effective siRNA target site and targeting heterogeneous sequences in a virus population. We show here that diced siRNA generated from long double-stranded RNA (dsRNA) is highly effective for inducing RNAi in HuH-7 cells harboring hepatitis C virus (HCV) replicons and can overcome variations in the HCV genotype. However, in mammalian cells, long dsRNA induced an interferon response and caused cell death. Here we describe an improvement of this method, U6 promoter-driven expression of long hairpin-RNA with multiple point mutations in the sense strand. This can efficiently silence HCV RNA replication and HCV protein expression without triggering the interferon response or cell death normally caused by dsRNA. In conclusion, intracellular-diced dsRNA efficiently induces RNAi, and, despite the high rate of mutation in HCV, it should be a feasible therapeutic strategy for silencing HCV RNA.

Clinical application of carbon fibre reinforced plastic leg orthosis for polio survivors and its advantages and disadvantages

A prospective study was carried out on the clinical application and features of a carbon fibre reinforced plastic leg orthosis (carbon orthosis) for polio survivors. The subjects comprised 9 polio survivors, and 11 carbon knee-ankle-foot orthoses (KAFOs) were prescribed, fabricated, and checked out at the authors' post-polio clinic. Walking was classified based on the functional ambulatory category, and the features of walking with a carbon orthosis were self-evaluated by using a visual analogue scale. The period from modelling a cast to completion was 55 +/- 25 days; the weight of a carbon KAFO was 27.8% lighter than that of the ordinary KAFO; the standard carbon KAFO was 50% more expensive than the ordinary KAFO. The carbon KAFO remained undamaged for at least 2 years. It improved the scores in the functional ambulation categories, but there was no difference between walking with an ordinary and with a carbon KAFO. The self-evaluation of walking with a carbon KAFO revealed that the subjects using a carbon KAFO were satisfied with their carbon KAFO. The carbon KAFO is lightweight, durable, slim and smart, and is positively indicated for polio survivors.

Frequent involvement of ras-signalling pathways in both polypoid-type and flat-type early-stage colorectal cancers

The development of colorectal neoplasms proceeds mainly via the adenoma-carcinoma sequence. BRAF and RASSF1A are members of Ras-signaling pathways, but the roles of their aberrations in colorectal carcinogenesis remain unclear. The authors studied mutations of the BRAF and K-ras genes, RASSF1A promoter methylation, and p53 overexpression in 43 polypoid-type and 30 flat-type early-stage colorectal cancers. No tumor simultaneously showed any combination of K-ras mutations, BRAF mutations, and RASSF1A promoter methylation. Three of the 73 tumors (4.1%) had BRAF mutations. All BRAF mutation-positive tumors were flat-type cancers, not associated with coexisting adenoma or p53 overexpression. RASSF1A promoter methylation was detected in 12 out of 73 tumors (16.4%), and the proportion of positive cases was similar in polypoid-type and flat-type cancers. BRAF mutations, K-ras mutations, and RASSF1A promoter methylation independently participate in early-stage colorectal carcinogenesis. BRAF mutations are involved only in flat-type cancers, whereas RASSF1A promoter methylation is involved in both polypoid-type and flat-type cancers. Thus, BRAF mutations most likely participate in de novo colorectal carcinogenesis, K-ras mutations in the adenoma-carcinoma sequence of colorectal carcinogenesis, and RASSF1A promoter methylation in both cascades.

Fermi surface and anisotropic spin-orbit coupling of Sb(111) studied by angle-resolved photoemission spectroscopy

High-resolution angle-resolved photoemission spectroscopy has been performed on Sb(111) to elucidate the origin of anomalous electronic properties in group-V semimetal surfaces. The surface was found to be metallic despite the semimetallic character of bulk. We clearly observed two surface-derived Fermi surfaces which are likely spin split, demonstrating that the spin-orbit interaction plays a dominant role in characterizing the surface electronic states of group-V semimetals. The universality or dissimilarity of the electronic structure in Bi and Sb is discussed in relation to the granular superconductivity, electron-phonon coupling, and surface charge or spin density wave.

Optimal dose for stage IIIB adenocarcinoma of the uterine cervix on the basis of biological effective dose

PURPOSE

Prognosis of uterine cervical adenocarcinoma in locally advanced stage treated with radiation therapy has been considered to be much worse than that of squamous cell carcinoma because the optimal dose for the former one has not been determined. Thus, the current study was performed to investigate the optimal dose for Stage IIIB, locally advanced stage, adenocarcinoma of the uterine cervix on the basis of the biological effective dose (BED).

METHODS

One-hundred and seventy-nine patients with Stage IIIB carcinoma of the uterine cervix were treated with curative intended therapy at Kitasato University Hospital between 1976 and 2000. Out of them, 13 patients had an adenocarcinoma component in pathological findings. Nine patients were diagnosed with adenocarcinoma and four patients were diagnosed with adenosquamous cell carcinoma. All patients were treated with external radiation therapy combined with intracavitary radiation therapy. The total BED10 (T-BED10) was caluculated from the BED of the external beam radiation therapy (E-BED10) plus the BED of the intra-cavitary radiation therapy (A-BED).

RESULTS

Overall survival rate was 51%. Stratified by T-BED10 overall survival rate of the T-BED10 > or = 100 Gy group was 57% and that of the T-BED10 < 100 Gy group was 30%. There was a trend toward a better survival rate of the T-BED10 > or = 100 Gy group than the T-BED10 < 100 Gy group.

CONCLUSION

The current study suggested that the optimal dose for Stage IIIB adenocarcinoma of the uterine cervix might be T-BED10 > or = 100 Gy.

Overexpression and purification of Aspergillus aculeatus beta-mannosidase and analysis of the integrated gene in Aspergillus oryzae

An expression plasmid for the manB gene encoding Aspergillus aculeatus beta-d-mannosidase (MANB) was constructed by using an expression vector carrying an improved promoter. After transformation of A. oryzae by the plasmid, several transformants formed colonies emitting fluorescence on a plate containing 4-methylumbelliferyl beta-d-mannopyranoside (MU-Man) under UV-irradiation. The transformant that displayed the strongest fluorescence, named A. oryzae BMN1, produced about 270 mg MANB/l in liquid culture. Recombinant MANB overproduced in BMN1 was purified by two steps of column chromatography to a single protein band on SDS-polyacrylamide gel electrophoresis and had a molecular weight of 130,000. Analyses by Southern blotting and genomic PCR demonstrated that a single copy of the plasmid was integrated into the chromosome by recombination at the niaD locus.

Cloning, nucleotide sequence and expression of the beta-N-acetylglucosaminidase gene from Aeromonas sp. no. 10S-24

The beta-GlcNAcase gene of Aeromonas sp. no. 10S-24 was cloned and sequenced. The gene consisted of 2505 bp encoding 835 amino acid residues. The amino acid sequence of the gene shares sequence homology with beta-GlcNAcases of Vibrio vulnificus (37.4%), Serratia marcescens (36.4%), V. harveyi (36.4%), V. parahemolyticus (33.5%), Alteromonas sp. strain O-7 (27.0%), and Candida albicans (28.6%). The beta-GlcNAcase gene of Aeromonas sp. no. 10S-24 was about 630-fold overexpressed in Escherichia coli compared to that in Aeromonas sp. no. 10S-24. The cloned beta-GlcNAcase had almost the same enzymatic properties as beta-GlcNAcase from no. 10S-24. The carbohydrate chain of beta-GlcNAcase from Aeromonas sp. no. 10S-24 was found to contain mannose, galactose, fucose, N-acetylglucosamine, N-acetylgalactosamine and several other unknown saccharides.

FIV-infected cats respond to short-term rHuG-CSF treatment which results in anti-G-CSF neutralizing antibody production that inactivates drug activity

The hematological and virological effects of recombinant human granulocyte colony-stimulating factor (rHuG-CSF) were evaluated in feline immunodeficiency virus (FIV)-infected cats. Six age-matched, FIV-infected cats used in this cross-over study were injected subcutaneously with 5 microg/kg of rHuG-CSF daily for 3 weeks, while six control cats received a placebo. Five of six rHuG-CSF-treated cats had significant increases in neutrophil counts that peaked on days 11-21 of treatment. All rHuG-CSF-treated cats exhibited an increase in myeloid:erythroid ratios of the bone marrow cells without significant changes in lymphocyte, CD4 counts, CD4/CD8 ratios, RBC counts, FIV antibody titers, and FIV loads in peripheral blood, and without clinical and hematological toxicities. Five of six rHuG-CSF-treated cats developed antibodies to rHuG-CSF by 14-21 days of treatment, which correlated with decreasing neutrophil counts and increasing neutralizing antibodies to rHuG-CSF. Three cats re-treated with rHuG-CSF rapidly developed neutralizing antibodies to rHuG-CSF, while one cat also developed neutralizing antibodies to recombinant feline G-CSF (rFeG-CSF). Overall, rHuG-CSF treatment increased neutrophil counts in FIV-infected cats without affecting the infection status of cats. However, long-term use of rHuG-CSF is not recommended in cats because of the neutralizing antibody production to rHuG-CSF that affects the drug activity. In addition, a preliminary finding suggests that repeated treatment cycle can also induce cross-neutralizing antibodies to rFeG-CSF, which may potentially affect the homeostasis of endogenous FeG-CSF.

Correlation of retinal sensitivity measured with fundus-related microperimetry to visual acuity and retinal thickness in eyes with diabetic macular edema

AIM

To determine whether significant correlations exist between retinal sensitivity measured by fundus-related microperimetry and the visual acuity and the foveal thickness measured by optical coherence tomography (OCT) in eyes with diabetic macular edema (DME).

METHODS

A retrospective chart review of 32 eyes with DME and 17 normal healthy eyes that had undergone fundus-related microperimetry and OCT. The macular sensitivity was measured using the recently introduced fundus-related microperimeter, Micro Perimeter 1. The mean retinal sensitivities within the central 2 degrees and 10 degrees were correlated with the best-corrected visual acuity and OCT-measured foveal retinal thickness.

RESULTS

The mean sensitivities in the central 2 degrees and 10 degrees were significantly lower in patients with DME than in normal subjects (P<0.0001). The mean retinal sensitivities in the central 2 degrees and 10 degrees were inversely correlated with visual acuity (r(2)=0.623, P<0.0001; r(2)=0.581, P<0.0001) and foveal thickness (r(2)=0.581, P<0.0001; r(2)=0.551, P<0.0001).

CONCLUSIONS

The mean retinal sensitivities measured with fundus-related microperimetry were significantly lower in eyes with DME than in normal eyes. Because a significant correlation of the microperimeter-determined retinal sensitivity to visual acuity and foveal thickness was observed, the retinal sensitivities obtained by fundus-related microperimetry may be another measure that can be used to assess the effects of DME.

Small-cell carcinoma of the uterine cervix: a clinicopathologic study of 11 cases

We report the clinical profiles and immunohistochemical features of small-cell carcinoma of the uterine cervix. Eleven cases that we have encountered at the Department of Gynecology, Kitasato University Hospital, between 1971 and 2003 are presented. Of 1370 invasive carcinomas of the uterine cervix, the incidence of small-cell carcinoma was 0.8%. Patient ages ranged between 32 and 65 years, with a mean age of 46.3 years. The clinical stages at diagnosis were Ib in four patients, IIb in three, IIIb in three, and IVb in one. All patients presented with abnormal vaginal bleeding. Two patients who are alive with no evidence of disease for 12 years and 3 years 6 months, while eight patients died of primary carcinoma between 4 and 25 months after treatment. Histopathologic findings showed solid nests with marked peripheral palisading pattern and rosette formation. Small tumor cells with scant cytoplasm demonstrated a very high nuclear/cytoplasm ratio and indistinct cell borders. The nuclei were round to oval and demonstrated increased but fine granular chromatin. Nucleoli were indistinct in all cases. Immunohistochemical findings were positive in 81.8% each for neuron-specific enolase and protein gene product 9.5, 72.7% for synaptophysin, 63.6% for chromogranin A, and 54.5% for neural cell adhesion molecule. All specimens were positive for at least one of the above. In conclusion, small-cell carcinoma of the uterine cervix revealed poor prognosis. Making an accurate diagnosis of small-cell carcinoma before performing treatment is of great significance but often difficult. Immunohistochemical analysis using several kinds of neuroendocrine markers is helpful in establishing the correct diagnosis in addition to focusing on characteristic histo- and cytopathologic features.

Small-cell carcinoma of the uterine cervix: a clinicopathologic study of 11 cases

We report the clinical profiles and immunohistochemical features of small-cell carcinoma of the uterine cervix. Eleven cases that we have encountered at the Department of Gynecology, Kitasato University Hospital, between 1971 and 2003 are presented. Of 1370 invasive carcinomas of the uterine cervix, the incidence of small-cell carcinoma was 0.8%. Patient ages ranged between 32 and 65 years, with a mean age of 46.3 years. The clinical stages at diagnosis were Ib in four patients, IIb in three, IIIb in three, and IVb in one. All patients presented with abnormal vaginal bleeding. Two patients who are alive with no evidence of disease for 12 years and 3 years 6 months, while eight patients died of primary carcinoma between 4 and 25 months after treatment. Histopathologic findings showed solid nests with marked peripheral palisading pattern and rosette formation. Small tumor cells with scant cytoplasm demonstrated a very high nuclear/cytoplasm ratio and indistinct cell borders. The nuclei were round to oval and demonstrated increased but fine granular chromatin. Nucleoli were indistinct in all cases. Immunohistochemical findings were positive in 81.8% each for neuron-specific enolase and protein gene product 9.5, 72.7% for synaptophysin, 63.6% for chromogranin A, and 54.5% for neural cell adhesion molecule. All specimens were positive for at least one of the above. In conclusion, small-cell carcinoma of the uterine cervix revealed poor prognosis. Making an accurate diagnosis of small-cell carcinoma before performing treatment is of great significance but often difficult. Immunohistochemical analysis using several kinds of neuroendocrine markers is helpful in establishing the correct diagnosis in addition to focusing on characteristic histo- and cytopathologic features

Secondary erythrocytosis associated with distal renal tubular acidosis

AIMS

Diagnosis and classification of renal tubular acidosis (RTA) have traditionally been made on the basis of functional studies. Despite recent expanding knowledge about the molecular abnormalities involved in renal bicarbonate (HCO3-) and H+ transport, the pathophysiology of secondary erythrocytosis in association with distal RTA remains obscure.

CASE HISTORY

A 2-month-old boy with severe hyperchloremic metabolic acidosis with positive urine anion gap was diagnosed with distal RTA. Replacement therapy with sodium bicarbonate and potassium citrate succeeded in improving his metabolic acidosis and growth. His renal function remained normal. He had persistent erythrocytosis.

CONCLUSION

Secondary erythrocytosis is a rarely reported association of distal RTA. It may increase the risk of thromboembolism.

Cellular immune responses to feline immunodeficiency virus (FIV) induced by dual-subtype FIV vaccine

Vaccine-induced T cell responses to FIV were assessed by measuring FIV-specific cytokine and cytotoxic-effector molecule production. A total of 22 cats at 10-12 weeks of age received either dual-subtype FIV vaccine (n=12), uninfected cell lysate (n=5) consisting of cells used to produce vaccine viruses, or no immunization (n=5). Significant increases in mRNA and protein production of T-helper 1 (Th1) cytokines (IL-2, IFNgamma), mRNA production of a cytotoxic-effector molecule (perforin), and lymphoproliferation response were observed in peripheral blood mononuclear cells (PBMC) from dual-subtype FIV-vaccinated cats after in vitro stimulation with inactivated FIV. In contrast, no statistically significant increase in FIV-stimulated mRNA production of Th2 cytokines (IL-4, IL-6) or other cytotoxic-effector molecules (TNFalpha, FasL) was observed in the PBMC from dual-subtype vaccinated cats. Moreover, no FIV-specific increases in the IFNgamma, IL-2, and perforin mRNA productions and in the IFNgamma bioactivity and lymphoproliferation responses were observed in the PBMC from cell-immunized cats. These observations suggest that IFNgamma induction, lymphoproliferation, and significant portion of IL-2 and perforin productions in the PBMC from dual-subtype vaccinated cats are clearly specific for viral antigens. Overall, dual-subtype FIV vaccine elicited strong Th1 response (IFN(, IL-2), which may contribute to the vaccine protection by enhancing the perforin-mediated cytotoxic-cell activity against FIV.

Rapid epidemiologic assessment of glucose-6-phosphate dehydrogenase deficiency in malaria-endemic areas in Southeast Asia using a novel diagnostic kit

We recently reported a new rapid screening method for glucose-6-phosphate dehydrogenase (G6PD) deficiency. This method incorporates a new formazan substrate (WST-8) and is capable of detecting heterozygous females both qualitatively and quantitatively. Here, we report its evaluation during field surveys at three malaria centres and in malaria-endemic villages of Myanmar and Indonesia, either alone or in combination with a rapid on-site diagnosis of malaria. A total of 57 severe (45 males and 12 females) and 34 mild (five males and 29 females) cases of G6PD deficiency were detected among 855 subjects in Myanmar whilst 30 severe (25 males and five females) and 23 mild (six males and 17 females) cases were found among 1286 subjects in Indonesia. In all cases, severe deficiency was confirmed with another formazan method but due to limitations in its detection threshold, mild cases were misdiagnosed as G6PD-normal by this latter method. Our results indicate that the novel method can qualitatively detect both severely deficient subjects as well as heterozygous females in the field. The antimalarial drug, primaquine, was safely prescribed to Plasmodium vivax-infected patients in Myanmar. Our new, rapid screening method may be essential for the diagnosis of G6PD deficiency particularly in rural areas without electricity, and can be recommended for use in malaria control programmes.

Induction of immune tolerance by neonatal intravenous injection of human factor VIII in murine hemophilia A

Inhibitory antibody formation is the most serious complication of factor (F)VIII replacement therapy in hemophilia A patients. FVIII-deficient mice were used to study new approaches for induction of immune tolerance. Neither antiFVIII inhibitory antibodies nor antiFVIII IgGs were observed in 13 of 14 adult mice that received 0.05 U g(-1) body weight of human FVIII intravenously within 24 h after birth and repeated injections as adults. In contrast, high FVIII antibody titers (>50 Bethesda Units mL(-1)) developed in seven of 13 mice injected on day 3 postpartum and in all adult mice not treated neonatally. One of nine mice and three of 17 mice developed high-titer antiFVIII inhibitory antibody when they were treated initially with 2-fold (0.1 U g(-1) body weight) and 10-fold higher doses (0.5 U g(-1) body weight) FVIII on day 0, respectively. A human FVIII-specific T-cell proliferative response was absent in splenocytes from neonatally treated mice. The tolerance was FVIII specific because antitoxoid antibodies developed after immunization with tetanus toxoid. Splenocytes failed to proliferate or produce interferon (IFN)-gamma in response to FVIII stimulation, yet still secreted interleukin-2. A proliferative response was restored with exogenous IFN-gamma or interleukin-12, suggesting that lack of inhibitor to FVIII was due to IFN-gamma-dependent anergy. Thus, exposure on day 0 to physiological levels of FVIII antigen might be important for induction of immune tolerance. This immune tolerance model may provide a basis for new approaches to prevention of FVIII inhibitors during replacement therapy.

Influence of occlusal contact on cervical muscle activity during submaximal clenching

The aim of this study was to clarify the relationship between changes in the occlusal contact area and cervical muscle activity. A decreases in the occlusal contact area using bite planes (stage 1: full contact bite plane, stage 2: bilateral molar removed from contact, and stage 3: bilateral molar and premolar removed from contact) was experimentally simulated in seven subjects (aged 23-25 years) with normal dentition, and muscle activity of the sternocleidomastoid muscle (SCM) and trapezius muscle (TRM) during 50 and 10% of maximum voluntary contraction (MVC) was measured by surface electromyography. The SCM activity during 50% MVC was stage 1: 31.2 +/- 9.4 microV and stage 3: 35.3 +/- 12.3 microV. The TRM activity during 50% MVC was stage 1: 15.2 +/- 0.7 microV and stage 3: 18.3 +/- 2.9 microV. At the 50% MVC, stage 3 showed significant differences in comparison with stage 1 (P < 0.05, anova). These findings suggested that the sternocleidomastoid and TRM play roles in the exertion of occlusal force, and decreases in the occlusal contact area influence the amount of SCM and TRM activity.

Excision of pseudotumour in a patient with haemophilia A and inhibitor managed with recombinant factor VIIa

We describe a patient with haemophilia A and factor VIII inhibitor who underwent surgical excision of a large pseudotumour in the left femoral region. Haemostasis was successfully maintained with bolus doses of recombinant factor VIIa at 2-h intervals and anti-fibrinolytic therapy, and the pseudotumour was removed. Subsequently, the dose interval was gradually prolonged to 8 h for a total of 18 days. Although a spontaneous haemorrhage was observed on postoperative day 8, haemostasis was achieved by reducing the dosage interval. No adverse event occurred during the course of treatment.

The dynamics of interactions between Plasmodium and the mosquito: a study of the infectivity of Plasmodium berghei and Plasmodium gallinaceum, and their transmission by Anopheles stephensi, Anopheles gambiae and Aedes aegypti

Knowledge of parasite-mosquito interactions is essential to develop strategies that will reduce malaria transmission through the mosquito vector. In this study we investigated the development of two model malaria parasites, Plasmodium berghei and Plasmodium gallinaceum, in three mosquito species Anopheles stephensi, Anopheles gambiae and Aedes aegypti. New methods to study gamete production in vivo in combination with GFP-expressing ookinetes were employed to measure the large losses incurred by the parasites during infection of mosquitoes. All three mosquito species transmitted P. gallinaceum; P. berghei was only transmitted by Anopheles spp. Plasmodium gallinaceum initiates gamete production with high efficiency equally in the three mosquito species. By contrast P. berghei is less efficiently activated to produce gametes, and in Ae. aegypti microgamete formation is almost totally suppressed. In all parasite/vector combinations ookinete development is inefficient, 500-100,000-fold losses were encountered. Losses during ookinete-to-oocyst transformation range from fivefold in compatible vector parasite combinations (P. berghei/An. stephensi), through >100-fold in poor vector/parasite combinations (P. gallinaceum/An. stephensi), to complete blockade (>1,500 fold) in others (P. berghei/Ae. aegypti). Plasmodium berghei ookinetes survive poorly in the bloodmeal of Ae. aegypti and are unable to invade the midgut epithelium. Cultured mature ookinetes of P. berghei injected directly into the mosquito haemocoele produced salivary gland sporozoites in An. stephensi, but not in Ae. aegypti, suggesting that further species-specific incompatibilities occur downstream of the midgut epithelium in Ae. aegypti. These results show that in these parasite-mosquito combinations the susceptibility to malarial infection is regulated at multiple steps during the development of the parasites. Understanding these at the molecular level may contribute to the development of rational strategies to reduce the vector competence of malarial vectors.

Reduction of viral myocarditis in mice lacking perforin

Cellular immunity plays an important role and contributes to morbidity and mortality in the development of cardiomyopathy secondary to acute myocarditis. Lymphocytotoxicity has been proposed as due to infiltrated cytotoxic T lymphocytes (CTLs). Perforin is thought to be a major factor responsible for the cytolytic properties of the CTLs. To investigate whether mice lacking perforin have enhanced severity of viral myocarditis and acceleration of myocardial apoptosis, perforin knockout (KO) mice were infected with encephalomyocarditis virus. The average cardiac viral titer in perforin KO mice was not significantly different from that in the wild type mice. The heart weight/body weight ratio in perforin KO mice on days 4 and 12 were the same in the wild type mice (n=4 of each). Hearts in perforin KO mice were smaller than that in perforin + mice and grades of myocardial necrosis and lymphocyte infiltration were significantly reduced than in perforin + mice on day 12 after viral inoculation. In the perforin KO mice, the number of apoptotic cells was significantly higher than in wild type on day 4. Perforin blockade induced the early induction of myocardial apoptosis and suppressed the late onset of myocardial injury by cellular autoimmunity. Blockade of perforin gene expression at an early stage may limit viral myocarditis for therapeutic intervention.

A mouse model of the atopic eczema/dermatitis syndrome by repeated application of a crude extract of house-dust mite Dermatophagoides farinae

BACKGROUND

We cultured Dermatophagoides farinae (Df), one of the most common mites in house dust and the most important allergen among natural allergens. With this material, we attempted to produce an animal model of the atopic eczema/dermatitis syndrome (AEDS).

METHODS

We cultured Df mites in high density and prepared a crude extract of Df (DfE) together with the culture medium. We applied the extract to the back skin of NC/Nga and BALB/c mice three times per week for 8 weeks.

RESULTS

In the NC/Nga group, dryness or scaling appeared on the skin, and scratching behavior increased at the second week in the DfE-treated group. Skin erosion and hemorrhage occurred at the fourth week. The epidermis thickened and deepened into the upper dermis, in which mast cells were highly accumulated, corresponding with the skin lesion of AEDS patients. Specific IgE and IgG to DfE and total IgE were elevated in the sera. Mice treated with an extract of mite culture medium did not develop skin lesions. In the BALB/c group, mice developed specific IgE and IgG to DfE, however, no typical skin lesions appeared. Mast cells in the upper dermis did not increase.

CONCLUSIONS

Repeated painting of Dermatophagoides extract produced IgE-associated AEDS-like lesions on the skin of NC mice.

Findings of pelvic musculature and efficacy of laparoscopic muscle stimulator in laparoscopy-assisted anorectal pull-through for high imperforate anus

BACKGROUND

Laparoscopic findings of levator muscle and the efficacy of laparoscopic muscle stimulator (LMS) in infants with high imperforate anus have not been reported.

METHODS

Twelve patients underwent laparoscopically assisted anorectoplasty for high imperforate anus. Following laparoscopic dissection of the distal rectum and division of the fistula, levator muscles in the pelvic floor were stimulated with a 5-mm-diameter LMS. Dilatation was done by inserting a guidewire and balloon catheter through the center of the levator muscle sling and muscle complex. Rectal pull-through and anastomosis between the rectum and anus were successfully completed.

RESULTS

LMS showed good contraction of levator muscles and enhanced accurate midline placement of pull-through rectum. LMS was particularly useful in observing weak muscles in infants with rectovesical fistula.

CONCLUSIONS

Laparoscopy and LMS offer excellent visualization of the pelvic musculature and precise tract of rectal pull-through. Fecal continence will be assessed by long-term follow-up.

Common cell-surface antigens functioning in self-recognition reactions by both somatic cells and gametes in the solitary ascidian Halocynthia roretzi

The "contact reaction" is an extremely rapid allogeneic cytotoxic reaction (ACR) mediated by hemocytes in the solitary ascidian Halocynthia roretzi. It has been proposed that regulation of the alloreactivity of hemocytes may be involved in preference for fertilization or self-sterility in this species. To identify the receptors and target ligands involved both in self-recognition by somatic cells and self-discrimination by gametes, we produced monoclonal antibodies (mAbs) that inhibit the ACR mediated by hemocytes and tested their effects on fertilization. Six different mAbs that inhibit the ACR were prepared and categorized into three groups. Although all three mAbs seemed to have the same ability to inhibit the ACR, almost constant and statistically significant inhibition (CRB1.1) and infrequent but significant inhibition (CRB2.1, and CRB3.1) of the ACR were observed in the same pairs of animals. Pretreatment of the unfertilized eggs with CRB1.1, CRB2.1, and CRB3.1, resulted in the constant and statistically significant inhibition, infrequent but significant inhibition, and no inhibition, respectively, of fertilization. Antigens recognized by CRB1.1 (CRB1.1 antigens) were detected on the cell surface of all types of hemocytes and on the vitelline coat and follicle cells of unfertilized eggs. CRB2.1 and CRB3.1 antigens were detected on the surface of certain types of hemocytes and follicle cells, but not on the vitelline coat. CRB mAbs were directed against different epitopes in the N-linked glycan on glycoproteins. These common carbohydrate antigens on somatic cells and gametes may function in some recognition processes in ACR and fertilization in H. roretzi.

[Mitral valve stenosis associated with a floating ball thrombus in the left atrium; report of a case]

A floating ball thrombus in the left atrium is relatively a rare case. A 70 year-old female patient who showed a symptom of heart failure was admitted to our hospital. By echocardiography, the mass in the dilated left atrium was appeared to be a floating ball thrombus, and the patient was diagnosed to be mitral valve stenosis. Following the treatment of heart failure, the patient underwent mitral valve replacement and the ball thrombus was successfully removed. Because of the high risk of sudden death with strangulated ball thrombus and systemic embolization, surgical removal of the ball thrombus should be done immediately after the diagnosis was established.

Cytokine production induced by a 67-kDa fimbrial protein from Porphyromonas gingivalis

Fimbriae have been reported to play an important role in the adherence of Porphyromonas gingivalis to oral surfaces and possibly in triggering host responses. P. gingivalis ATCC 33277 has two distinctly different fimbriae expressed on the cell surface. The 67-kDa fimbriae differ in size and antigenicity from the earlier reported FimA, a major 41-kDa fimbrial component of P. gingivalis. Expression of the 67-kDa fimbriae on the cell surface of a fimA mutant was investigated by electron microscopy. The 67-kDa fimbrial protein was purified from the fimA mutant by sonication, precipitation, and chromatography on a DEAE Sepharose CL-6B column. The N-terminal amino acid sequence of the 67-kDa fimbrillin was distinct from that of the 41-kDa fimbrillin. Moreover, we have found that the 67-kDa fimbrial protein from P. gingivalis ATCC 33277 induced IL-1alpha, IL-beta, IL-6 and TNFalpha cytokine expression in mouse peritoneal macrophages. These results suggest that P. gingivalis 67-kDa fimbriae may play a part in the inflammatory response during the development of periodontal diseases.

Newly developed immobilized polymyxin B fibers improve the survival of patients with sepsis

BACKGROUND

Sepsis and septic shock are still major causes of morbidity and mortality in spite of the availability of powerful and broadly active antibiotics.

METHODS

A prospective, open and randomized trial of the effect of immobilized polymyxin fibers (PMX-F) on the survival of patients with sepsis throughout a follow-up period of 28 days or until discharge, if earlier, was carried out. Ninety-eight patients were included who met at least 4 of the criteria for systemic inflammatory response syndrome due to infection. The patients were classified into three groups based on their Acute Physiology and Chronic Health Evaluation (APACHE) II score.

RESULTS

The overall survival rate was significantly improved by using PMX-F compared to the control group (41 vs. 11%) (p = 0.002). In patients with an APACHE II score less than 20, treatment with PMX-F was shown to improve outcome (65 vs. 19%) (p = 0.01). In cases of more severe sepsis with an APACHE II score of 20-29, PMX-F still maintained efficacy in improving outcome (40 vs. 11%) (p = 0.04). However, PMX-F treatment did not improve the survival rate in patients with an APACHE II score of greater than 30 (survival rate 7 vs. 0%) (p = 0.59).

CONCLUSION

From these results, it is concluded that treatment with PMX-F in patients with sepsis is effective and prolongs the survival rate when applied at an early stage of sepsis. However, in severe sepsis, this therapy does not improve the survival rate.

N-methyl-1-deoxynojirimycin (MOR-14), an alpha-glucosidase inhibitor, markedly improves postischemic left ventricular dysfunction

We examined whether pharmacological inhibition of glycogenolysis by N-methyl-1-deoxynojirimycin (MOR-14), a new compound which reduces the glycogenolytic rate by inhibiting the alpha-1,6-glucosidase activity of the glycogen-debranching enzyme, can protect the heart against postischemic left ventricular dysfunction. The hearts of male Sprague-Dawley rats were excised, and perfused on a Langendorff apparatus with Krebs-Henseleit solution with a gas mixture of 95% O2 and 5% CO2. The hearts were paced at 320 beats/min except during the ischemia. Left ventricular developed pressure (LVDP, mmHg), +/-dP/dt (mmHg/s), and coronary flow (ml/min) were continuously monitored. All hearts were perfused for a total of 120 min including a 30-min preischemic period followed by a 30-min episode of global ischemia and 60 min reperfusion. with or without 0.5 or 2 mM of MOR-14 during the 30-min preischemic period or the first 30 min of reperfusion. In another series of experiments, the myocardial content of glycogen and lactate was measured during the 30-min episode of ischemia in groups treated with and without 2mM of MOR-14. Preischemic but not postischemic treatment with MOR-14 significantly improved LVDP and +/-dP/dt without altering coronary flow during reperfusion in a dose-dependent manner. MOR-14 significantly preserved the glycogen content and significantly attenuated the lactate accumulation during the 30-min episode of ischemia. Preischemic treatment with MOR-14 is protective against postischemic left ventricular dysfunction through the inhibition of glycogenolysis in the isolated rat heart.

Ground-glass hepatocytes in fibrinogen storage disease in Japanese Black calves

This paper reports the occurrence of large intracytoplasmic inclusions observed in the hepatocytes of six Japanese Black calves showing clinical illness. These inclusions were round to elongated polyhedral in shape, with a consistently homogeneous glassy appearance. Hepatocytes with the inclusions had a ground-glass appearance. The inclusions were negative for the periodic acid-Schiff reaction and methenamine silver stain. Immunohistochemically, they were strongly positive for fibrinogen. Electron microscopy revealed that the inclusions consisted of granular material, showing moderate electron density and bounded by a unit membrane. On the external surface of the unit membrane, there were direct connections to cellular organelles, including the ribosomes and rough-surfaced endoplasmic reticulum. The results showed these inclusions to be entirely consistent with fibrinogen inclusions described in man. Hepatocellular fibrinogen storage disease, as identified in this study, has not previously been described in animals.

Treatment with sheng-mai-san reduces myocardial infarct size through activation of protein kinase C and opening of mitochondrial KATP channel

Sheng-mei-san (SMS), a traditional Chinese formulation comprising Radix Ginseng, Radix Ophiopogonis and Fructus Schisandrae, has long been used for more than 700 years for patients with coronary heart disease. We attempted to clarify 1) whether SMS reduces myocardial infarct size, and 2) whether the infarct size-reducing effect of SMS is related to activation of protein kinase C and the opening of the mitochondrial KATP channels in Japanese white rabbits without collateral circulation. The results indicate that three days treatment but not acute treatment with SMS reduces myocardial infarct size through activation of protein kinase C and opening of the mitochondrial KATP channels.