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Biomedical subjects

H Saida

Publications and source records attributed to H Saida.

8 recordsLinked to original sources
PubMed2000

Gram stain index of a natural bacterial community at a nutrient gradient in the freshwater environment.

Species succession of a natural bacterial community was indicated by the Gram stain index (GSI) using an experimental nutrient gradient in an oligotrophic pond created with an in situ gradostat. Various trophic conditions, ranging from eutrophic to mesotrophic, were formed experimentally with continuous inflow of sterile peptone solution in the gradostat, while the water mass outside the gradostat was oligotrophic. The GSI spectra of the natural bacterial populations show different profiles in accordance with the trophic level of the ambient water and the time progression of adaptation to different levels of eutrophication. Therefore, GSI can be used as a potential indicator of organic pollution in aquatic environments.

Journal Article↗
PubMed1998

In situ gradostat for the study of a natural phytoplankton community with an experimental nutrient gradient.

A new in situ gradostat was devised to study the dynamics of natural communities having nutrient gradients within aquatic habitats. This semi-enclosed mesocosm consisted of three components: i.e. three transparent, concentric cylindrical culture chambers, with diameters of 70, 60 and 40 cm, and 20 cm deep, supported by four flotation buoys, a medium reservoir, and a pump to supply the medium to the mesocosm. Water exchange between compartments was achieved via holes in the cylindrical walls, the number and size of the holes being chosen to regulate the rate of exchange. Sterile culture medium was pumped into the central (first) chamber and diffused outwards into the second and third chambers through the perforated walls. Suitable perforations could achieve a concentration gradient of up to 9.5 times between the first and third chambers within 12 h. The system was designed with the following characteristics: (1) an experimental semi-enclosed system in the natural environment; (2) to maintain equivalence with the external water except for the experimental factors; and (3) to form a manipulable gradient of experimental factors across the mesocosm. Using the in situ gradostat, the response of a natural phytoplankton community to a nitrate gradient was determined. A gradient from oligotrophic to eutrophic was maintained for 10 days in an oligotrophic pond. The mean growth rate of phytoplankton was lower in the eutrophic zone than that in the mesotrophic zone, where the highest mean growth rate was observed. The growth rate of each dominant phytoplankter showed its own pattern, but all rates were highest in the mesotrophic environment of the second chamber.

Journal Article↗
PubMed1998

Photometric application of the Gram stain method to characterize natural bacterial populations in aquatic environments.

The Gram stain method was applied to the photometric characterization of aquatic bacterial populations with a charge-coupled device camera and an image analyzer. Escherichia coli and Bacillus subtilis were used as standards of typical gram-negative and gram-positive bacteria, respectively. A mounting agent to obtain clear images of Gram-stained bacteria on Nuclepore membrane filters was developed. The bacterial stainability by the Gram stain was indicated by the Gram stain index (GSI), which was applicable not only to the dichotomous classification of bacteria but also to the characterization of cell wall structure. The GSI spectra of natural bacterial populations in water with various levels of eutrophication showed a distinct profile, suggesting possible staining specificity that indicates the presence of a particular bacterial population in the aquatic environment.

Bacillus subtilis↗
PubMed1996

Acoustic changes in voice after tonsillectomy.

UNLABELLED: The vocal tract from the glottis to the lips is considered to he a resonator and the voice is changeable depending upon the shape of the vocal tract. In this report, we examined the change in pharyngeal size and acoustic feature of voice after tonsillectomy. METHODS: Subjects were 20 patients. The distance between both anterior pillars (glossopalatine arches), and between both posterior pillars (pharyngopalatine arches) was measured weekly. For acoustic measurements, the five Japanese vowels and Japanese conversational sentences were recorded and analyzed. RESULTS: The distance between both anterior pillars became wider 2 weeks postoperatively, and tended to become narrower thereafter. The distance between both posterior pillars became wider even after 4 weeks postoperatively. No consistent changes in F0, F1 and F2 were found after surgery. Although there was a tendency for a decrease in F3, tonsillectomy did not appear to change the acoustical features of the Japanese vowels remarkably. It was assumed that the subject may adjust the shape of the vocal tract to produce consistent speech sounds after the surgery using auditory feedback.

Adult↗
PubMed1995

Acarboxy prothrombin (PIVKA II) as a tumour marker for hepatocellular carcinoma and other liver diseases.

The clinical usefulness of plasma abnormal prothrombin, defined as protein induced by vitamin K absence or antagonist II: (PIVKA II) as a tumour marker for hepatocellular carcinoma (HCC) and other liver diseases has been evaluated. PIVKA II concentrations were determined using an enzyme-linked immunosorbent assay (ELISA) with monoclonal antibody that reacts with PIVKA II but does not cross-react with normal prothrombin. Seventy four patients (74%) out of 100 with HCC had abnormal PIVKA II levels above 0.5 AU/ml (median = 3.4 AU/ml). The level was above 1.0 AU/ml in 66 (66%) of the patients. In contrast the level of PIVKA II was low in patients with bilharzial periportal fibrosis (median = 0.09 AU/ml), patients with liver cirrhosis (median = 0.13 AU/ml), patients with hepatitis (median = 0.025 AU/ml), and essentially undetectable in all the 34 controls. The diagnostic ability of serum alphafoetoprotein (AFP) was also evaluated in these patients. AFP alone can diagnose 51% of the HCC cases. Of the remaining patients with low or negative AFP levels (65%) can be diagnosed using PIVKA II. Abnormal prothrombin is a potential marker for the laboratory diagnosis of hepatocellular carcinoma.

Adult↗
PubMed1990

[A study of voice mutation and physical growth--a longitudinal observation].

Past studies on the relationship between mutational voice change and body growth were generally made on grouped subjects and no exact longitudinal observation was performed. In the present report, a longitudinal study was made on 100 young male students in their puberty, in which voice recordings and measurements of physical parameters including body height and weight were performed twice for each subject with yearly interval. Information on subjective evaluation of voice abnormality was also obtained from each subject. The recorded voice samples were subjected to subsequent analysis for obtaining fundamental frequency (F0) and formant values. The following results were obtained. 1. A negative correlation in the rate of change was observed between F0 and physical parameters such as body height and weight, and sitting height. 2. It was suggested that the mutational period consisted of the rapid and slow phases. The rate of growth in body height and sitting height was more significant in the rapid phase. 3. Subjective voice abnormality and physical growths such as the development of the laryngeal prominence were often noted even before the rapid phase. After the rapid phase was over, all the cases showed secondary sexual characteristics including the laryngeal prominence. 4. Before and during the rapid phase, there was a tendency for the values of F1 and F2 to increase, while that of F3 to decrease. After the rapid phases was over, there was a trend that F1 and F2 increased, while F3 remained unchanged.

Adolescent↗