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Biomedical subjects

A Sano

Publications and source records attributed to A Sano.

At least 55 records · Page 3Linked to original sources

Atypical Cryptococcus neoformans isolate from an HIV-infected patient in Brazil.

Cryptococcus neoformans is an important fungal pathogen in immunocompromised hosts. Capsulation, urease and melanin synthesis activity of the fungus are well known virulence factors. Although artificial melanin-deficient mutants of Cr. neoformans have been investigated, the clinical mutant is rare. We found a Cr. neoformans isolate in the cerebrospinal fluid of an AIDS patient which produced a light tan colony on a caffeic acid cornmeal agar (CACA) plate. The mycological feature of the isolate was as follows; normal capsulation, defective inositol assimilation ability, serotype A; urease-positive; mating type alfa; haploid; extremely slow growth in RPMI 1640 medium, Sabouraud dextrose broth, brain heart infusion broth and yeast nitrogen base; lower production of melanin with L-DOPA substrate; and low virulence to ddY mice. We also investigated the partial DNA sequence of CNLAC1 gene between the 3085th to 3623rd base. There were many substitutions, 3 insertions and 3 deletions in the isolate compared with GenBank accession number L22866. The result indicated some functional disorder in the gene. Although the CACA plate is an excellent selective medium for Cr. neoformans, other identification methods should also be used.

Acquired Immunodeficiency Syndrome↗

[Two cases of canine histoplasmosis in Japan].

Histoplasmosis is distributed in tropical, subtropical and temperate zones of the world. The disease is one of the imported mycoses in Japan. To date, although more than 30 human and one canine case of histoplasmosis have been reported in Japan, some including that of the canine might have been infected domestically, since the patients have no history of going abroad. The pathogen of histoplasmosis is thus believed to be present in our country. We examined skin biopsies from two dogs in Tokyo and Kumamoto, and found fungal elements 1-2 or 2-4 microEm in diameter in the macrophages. The homology of DNA sequences for the ITS rRNA gene were correspondent to Ajellomyces capsulatus at a rate of more than 97.4%. Therefore, the two dogs were diagnosed as having been infected with Histoplasma capsulatum which is the anamorph of A. capsulatus. Since the dogs had no history of having been outside Japan and had not been brought from an endemic area, they might have been infected domestically. Further epidemiological surveys on canine histoplasmosis may be able to estimate autochthonous human cases in Japan.

Animals↗

Detection of gp43 and ITS1-5.8S-ITS2 ribosomal RNA genes of Paracoccidioides brasiliensis in paraffin-embedded tissue.

Paracoccidioidomycosis (PCM) is a deep mycosis caused by the thermo-dependent dimorphic fungus Paracoccidioides brasiliensis and is prevalent in Latin American countries. An increase in PCM has been reported in recent years and the disease is now recognized as one of the imported fungal infections in Japan. To date, more than 15 cases of PCM have been reported in our country, and five of them were diagnosed by clinical and histopathological findings without mycological study. We applied 2 nested polymerase chain reaction (PCR) amplification methods for detecting P. brasiliensis genes from paraffin-embedded tissue specimens. Successfully amplified were: a 473 base pairs fragment of gp43 gene of P. brasiliensis (located from 741st to 1,213rd base), and a 418 base pairs fragment of 5.8S ribosomal RNA gene of P. brasilienisis which included internal transcribed spacers (ITS) 1 and 2 (located from 131st at ITS1 to 195th at ITS2) in paraffin-embedded murine tissues infected with P. brasiliensis yeast cells. The authenticity of the PCR products was confirmed by nucleotide sequence analysis. These results indicate that the two nested PCR methods may be useful for diagnosis of PCM.

Animals↗

Localization of primordial germ cells or their precursors in stage X blastoderm of chickens and their ability to differentiate into functional gametes in opposite-sex recipient gonads.

This study was performed to determine the distribution of primordial germ cells and their precursors in stage X blastoderm of chickens. The blastoderm (Barred Plymouth Rock chickens) isolated from the yolk was separated into three portions: the central disc, the marginal zone and the area opaca. The dissociated blastodermal cells derived from the central disc, marginal zone and area opaca were transferred into a recipient blastoderm (White Leghorn chicken) from which a cell cluster was removed from the centre of the central disc. The manipulated embryos were cultured in host eggshells until hatching. The chicks were raised until sexual maturity and test mated with Barred Plymouth Rock chickens to assess the donor cell contribution to the recipient germline. Germline chimaeric chickens were produced efficiently (46.7%, 7/15) when the blastodermal cells derived from the central disc were transferred into recipient embryos of the same sex, whereas no germline chimaeric chickens were produced when the blastodermal cells derived from the marginal zone or area opaca were transferred into recipient embryos of the same sex (0/12). Germline chimaeric chickens were also produced by transfer of blastodermal cells derived from the central disc (6.7%, 1/15), marginal zone (10.0%, 1/10) or area opaca (11.1%, 1/9) into recipient embryos of the opposite sex. It is concluded that primordial germ cells are induced during or shortly after stage X and that the cells derived from the central disc have the highest potential to give rise to germ cells. Cells derived from the marginal zone and area opaca can also give rise to germ cells, although the frequency is low.

Animals↗

[Two cases of visceral larva migrans due to Ascaris suum showing a migratory nodular shadow].

The number of cases of visceral larva migrans caused by the pig ascarid, Ascaris suum has recently been increasing. We have encountered two cases of visceral larva migrans due to A. suum with a nodular shadow on the chest radiograph and eosinophilia in the peripheral blood. Patient 1 was a 26-year-old man who had been admitted to our hospital for an elective minor operation. His chest radiology and chest computed tomography revealed a nodule in the left lung field. Peripheral blood eosinophil counts and serum IgE values were elevated. Radiological abnormality disappeared without treatment. Patient 2 was a 57-year-old man who had been admitted to our hospital because of a migratory nodule on chest radiography and eosinophilia in the peripheral blood. The diagnosis of visceral larva migrans caused by A. suum was made because the serum of both patients was positive for an antibody against A. suum. Patient 1 and patient 2 were accustomed to eating the raw flesh of wild boar and deer, and of chicken and turkey, respectively. Treatment with albentazole was effective in these patients.

Adult↗

[Clinical features in twenty-three patients with paragonimiasis westermani].

We assessed the clinical features in twenty-three cases diagnosed as paragonimiasis westermani from April 1988 to May 2000 in our clinic at Miyazaki Medical College Hospital. Twenty-one patients had eaten wild boar or crab meat. Their symptoms included productive cough, chest pain and hemosputum. The findings of radiography and computed tomography (CT) were nodules, masses, infiltrative shadows and pleural effusion. The percentages of eosinophils in the peripheral blood were elevated in 16 of 23 patients, and the serum IgE values were elevated in 12 of 18 patients. Serologic tests, which are very helpful for diagnostic purposes were performed on the blood sera of all patients, and on the pleural effusions of five patients. It is often difficult to diagnose paragonimiasis westermani in patients in whom eosinophilia or increased serum IgE is not present. However, paragonimiasis westermani should also be considered as a possible diagnosis when abnormal shadows are found in chest radiographs and chest CT.

Adolescent↗

A surrogate method for assessment of beta(2)-integrin-dependent adhesion of human eosinophils to ICAM-1.

We have developed and validated an inexpensive and equivalent method for measuring eosinophil adhesion by beta(2)-integrin to endothelial ICAM-1 using bovine serum albumin (BSA) as a surrogate for the immunoglobulin supergene. The number of adherent eosinophils on BSA or ICAM-1 coated microplates was quantified by residual eosinophil peroxidase activity. Non-stimulated eosinophils did not adhere to either BSA or ICAM-1. However, after IL-5 stimulation, either BSA or ICAM-1 caused comparable and concentration-dependent adhesion of eosinophils. Eosinophil adhesion was rapid and occurred within 15 to 30 min of incubation for either BSA or ICAM-1. Preincubation of cells with CD11b or CD18 antibody specifically decreased adhesion to either BSA or ICAM-1. IL-5, PAF and fMLP all induced adhesion of eosinophils to either BSA or ICAM-1 in a concentration-dependent manner, and the optimal IL-5, fMLP and PAF concentrations for adhesion to BSA were the same as for adhesion to ICAM-1. BSA-binding was specific for beta(2)-integrin; neither alpha-CD49d mAb directed against the alpha(4)-chain or alpha-CD29 directed against the common beta(1)-chain of VLA-4 blocked adhesion to BSA or ICAM-1 controls. The protein tyrosine kinase inhibitor, genistein, the phosphatidylinositol 3-kinase (PI-3 kinase) inhibitor, wortmanin, and mitogen-activated protein kinase kinase (MEK) inhibitor, U0126, all inhibited IL-5-induced eosinophil adhesion to either BSA or ICAM-1 comparably. These results indicate that BSA is a reliable and economical surrogate ligand for ICAM-1 adhesion to beta(2)-integrin-dependent adhesion to ICAM-1. Ligation characteristics of BSA are identical to those for soluble ICAM-1, and the assay is suitable for assessment of signal transduction pathways mediating adhesion.

Androstadienes↗

Development of new drug delivery system for protein drugs using silicone (I).

A novel technique, by which protein drugs effective in small doses can be released over a long period, was developed using silicone and a water-soluble substance. In this study, interferon (IFN) was used as a model of the protein drugs. The IFN-silicone formulation released IFN over long periods of time in vitro and suppressed tumor growth in nude mice for about 100 days after a single administration. This indicates that physiologically active IFN is released over a prolonged period of time from the IFN-silicone formulation in vivo. Silicone formulations are expected to be a practically feasible sustained-release formulation.

Animals↗

The crystal structure of a Dcp-containing peptide.

We have investigated the conformational preferences of a newly synthesized C(alpha,alpha) symmetrically disubstituted glycine, namely alpha,alpha-dicyclopropylglycine (Dcp). We report here the crystal structure of a fully protected dipeptide containing Dcp, namely Z-Dcp(1)-Dcp(2)-OCH(3). Both Dcp residues are in a folded conformation. The overall peptide structural organization corresponds to an alpha-pleated sheet conformation, similar to that observed in linear peptides made up of alternating D- and L-residues and in Z-Aib-Aib-OCH(3) (Aib: alpha,alpha-dimethylglycine). These preliminary data suggest that the Dcp could represent an alternative as molecular tool to stabilize folded conformations.

Crystallography, X-Ray↗

Pentobarbital stimulates the activity of the GnRH pulse generator interacting with opioid neurons in rats in proestrus.

In order to investigate the possibility that i.p. injection of pentobarbital sodium (PB, 32 mg/kg bw) potentiates the GnRH pulse generator activity, effects of i.v. infusions of an opiate receptor antagonist naloxone (NAL, 2 mg/h) on the pulsatile LH secretion were compared in saline (SAL)- and PB-injected rats in proestrus and diestrus 1. In SAL-injected rats in proestrus, NAL infusions significantly increased both the frequency and amplitude of LH pulses, and also the overall mean LH concentration. In PB-injected rats in proestrus, all the parameters of the pulsatile LH secretion were similar to those in SAL-injected rats in proestrus. The NAL infusion in PB-injected rats caused an increase in the frequency, but it was similar to that in SAL-injected rats. But, increases in the amplitude and the overall mean LH observed during NAL infusions in PB-injected rats were greater than in SAL-injected rats. In SAL-injected rats in diestrus 1, NAL infusions increased all the parameters, as in rats in proestrus. In PB-injected rats in diestrus 1, LH secretion was severely suppressed. NAL infusions recovered the pulsatile LH secretion, but the frequency and the overall mean LH of the secretion were smaller than those obtained during NAL infusions in SAL-injected rats. In addition, characteristic increases in the MUA (volleys), which occur in association with the initiation of an LH pulse and thus are considered to represent an increased activity of the GnRH pulse generator, appeared more frequently during NAL infusions in PB-injected rats in proestrus than in SAL-injected rats. These results suggest that the GnRH pulse generator in rats in proestrus, but not in rats in diestrus 1, is refractory to PB and further is potentiated by PB in the response to NAL. Together with the fact that this dosage of PB blocks the surge of LH secretion in rats in proestrus, the concept of the existence of separate neuronal mechanisms responsible for the surge and pulsatile secretion of LH are supported.

Action Potentials↗

Controlled local application of basic fibroblast growth factor (FGF-2) accelerates the healing of GBR. An experimental study in beagle dogs.

This animal study was performed to ascertain whether the regeneration of membrane-protected bone defects can be accelerated by the controlled application of basic fibroblast growth factor (FGF-2) using a new drug delivery system. Standardized alveolar bone defects were made surgically in 9 beagle dogs, and FGF-2 was administered using specially made collagen minipellets. A minipellet containing either 0.15 microgram FGF-2 (FGF) or 0 microgram FGF-2 (placebo) was placed in the defect or no minipellet was used (control), and bone regeneration was evaluated radiologically, histologically, and histometrically 8 weeks after the operation. Radiographs showed a surprisingly large radiopaque region in FGF sites compared with placebo or control sites. Histologically, mature bone filled the majority of the inner space of the membrane-protected defect in FGF sites. New bone formation was also seen in the control and the placebo sites, however, it filled less than half the area of the defect. Histometrically, the area of regenerated bone in FGF sites was significantly higher than in the other sites (P < 0.01). These results demonstrate that the controlled application of FGF-2 accelerates bone regeneration in membrane-protected bone defects in the canine model.

Alveolar Process↗

The human serotonin transporter gene linked polymorphism (5-HTTLPR) shows ten novel allelic variants.

The serotonin transporter (5-HTT) gene is a promising candidate for introducing the heritability of interindividual variation in personality and the genetic susceptibility for various psychiatric diseases. Transcription of the gene is modulated by a common polymorphism in its upstream regulatory region (5-HTT gene-linked polymorphic region: 5-HTTLPR). The 5-HTTLPR consists of variation of the repetitive sequence containing GC-rich, 20-23-bp-long repeat elements. A deletion/insertion in the 5-HTTLPR was first reported to create a short (S) allele and a long (L) allele (14- and 16-repeats, respectively). Three other kinds of alleles (18-, 19- and 20-repeats) in addition to the S and L alleles in 5-HTTLPR have been reported. In the present study, we examined the 5-HTTLPR polymorphism in detail and identified ten novel sequence variants, concluding that the alleles reported as S and L are divided into four and six kinds of allelic variant, respectively. Subsequently, we developed a method for genotyping. The total number of alleles (14-A, 14-B, 14-C, 14-D, 15, 16-A, 16-B, 16-C, 16-D, 16-E, 16-F, 19, 20 and 22) in the 5-HTTLPR was 14 in our populations (Japanese: n = 131; Caucasian: n = 74) in the present study. In addition, a significant ethnic difference between Japanese and Caucasian populations was observed for distributions of alleles and genotypes (P < 0.0001 and P < 0.0001, respectively). Our results suggest that the analyses of the 5-HTTLPR should be revised by genotyping with a more complete subdivision of alleles. Molecular Psychiatry (2000) 5, 32-38.

Alleles↗

Development of a rapid positive/absent test for coliforms using sensitive bioluminescence assay.

We have developed a sensitive bioluminescence assay for beta-galactosidase using a luminescent substrate, D-luciferin-O-beta-galactopyranoside (LuGal). The detection limit for beta-galactosidase was 3 x 10-20 mol per assay, which was approximately 50-fold more sensitive than the test using a fluorescent substrate. This assay was applied to a positive/absent (P/A) test for coliforms. Observations made after 7 h of culture followed by a 10-min enzyme assay using LuGal were comparable to those made after a 22-24-h culture by the current method. Therefore, the LuGal method allows a rapid P/A test for coliforms.

Bacteriological Techniques↗

A new PCR primer for the identification of Paracoccidioides brasiliensis based on rRNA sequences coding the internal transcribed spacers (ITS) and 5 x 8S regions.

Internal transcribed spacer (ITS) genes including the 5.8S ribosomal (r)RNA of Paracoccidioides brasiliensis were amplified and the DNA sequences were determined. Based on a comparison of the sequence information, a new polymerase chain reaction (PCR) primer pair was designed for specific amplification of DNA for P. brasiliensis. This primer pair amplified a 418-bp DNA sequence and was 100% successful in identifying 29 strains of P. brasiliensis (including the reference strains) isolated from the regions of Brazil, Costa Rica, Japan, Argentina or from different sources. The results of specificity tests of these primers to compare the fungus with those of Aspergillus fumigatus, Blastomyces dermatitidis, Candida albicans, Cryptococcus neoformans, Histoplasma capsulatum and Penicillium marneffei are also reported.

DNA Primers↗

Electrical activity of the pulse generator of gonadotropin-releasing hormone in 26-month-old female rats.

To know whether age-related changes occur in the activity of the pulse generator of gonadotropin-releasing hormone (GnRH), old (26 months) and young (3 months) female rats were examined by recording multiunit activity (MUA) in the median eminence region of the hypothalamus, concurrently with blood samplings through an intra-atrial cannula at 6-min intervals to determine serum luteinizing hormone (LH) concentrations. We have regarded the MUA showing intermittent increases (volleys) at 20-30 min intervals, followed by LH pulses, as the electrical activity of the GnRH pulse generator. We were successful in recording MUA in 18 (26%) of 69 old ovariectomized rats and in 8 (32%) of 25 young ovariectomized rats. The overall mean (+/-SE) of the interval between MUA volleys in old ovariectomized rats was 35.1 +/- 2.0 min (n = 18), which was significantly longer than that of 22.5 +/- 1.5 min (n = 8) in young ovariectomized rats. The mean interval between LH pulses in old ovariectomized rats was 32.2 +/- 3.6 (n = 10), also being significantly longer than that of 23.3 +/- 1.0 (n = 8) in young ovariectomized rats. Further, the LH pulse amplitude in old rats (0. 95 +/- 0.07 ng/ml) was significantly smaller than in young rats (3. 40 +/- 0.36 ng/ml). The present study also confirmed that the increase in serum LH after intravenous injection of 50 ng GnRH was much smaller in old ovariectomized rats. These results show that the electrical activity of the GnRH pulse generator is certainly reduced with age. Taken together with findings suggesting an age-dependent decrease in stimulated transmitter release, attenuation in both frequency and amplitude of GnRH pulses as well as in pituitary responsiveness to GnRH pulses may account for the decreased pulsatile LH secretion observed in aging rats.

Aging↗

The depressor function of biceps on the head of the humerus in shoulders with tears of the rotator cuff.

We investigated the function of biceps in 18 patients (19 shoulders) with lesions of the rotator cuff. Their mean age was 59 years. Another series of 18 patients (19 shoulders) with normal rotator cuffs as seen on MRI acted as a control group. Their mean age was 55 years. A brace was used to maintain contraction of biceps during elevation. Anteroposterior radiographs were obtained with the arm elevated at 0 degrees , 45 degrees and 90 degrees with and without contraction of biceps. The distance between the centre of the head of the humerus and the glenoid was compared in the two groups. We found that in the group with tears there was significantly greater proximal migration of the head of the humerus at 0 degrees and 45 degrees of elevation without contraction of biceps but depression of the head of the humerus at 0 degrees, 45 degrees and 90 degrees when biceps was functioning. We conclude that biceps is an active depressor of the head of the humerus in shoulders with lesions of the rotator cuff.

Adult↗

Isolation of Candida dubliniensis from the oral cavity of an HIV-positive child in Brazil.

Candida dubliniensis is a newly-recognized Candida species and an important infectious pathogen, particularly for HIV-positive patients. >From oral smear samples from the radix linguae of 173 HIV-positive children, we obtained four yeast isolates which took a blue-green color on CHROMagar Candida plate at 37 degrees C for 48 hours from one HIV-positive 3-year-old boy in Brazil. The isolates were difficult to grow on potato dextrose agar plate at 42 degrees C, produced abundant chlamydospores on a cornmeal agar plate with Tween 80, and sprouted germ tubes in saline with horse serum, and the antigenic profile by CANDIDA CHECK test was useless. Carbohydrate assimilation tests by ID32C showed no reference code number in the reference book. The isolates were subjected to molecular biological assay of the DNA sequence of the large-subunit ribosomal DNA region (D1/D2) and randomly amplified polymorphic DNA (RAPD). The DNA sequence agreed with those of standard C. dubliniensis strains, and therefore, the isolates were identified as C. dubliniensis. RAPD band pattern analysis indicated that the clinical isolates might summarize one genotype. Although the child did not present oral lesions, the fungus might be latent for opportunistic infection.

Brazil↗