PubMed Health⌕ Search

Biomedical subjects

T Toma

Publications and source records attributed to T Toma.

At least 37 records · Page 2Linked to original sources
PubMed1999

Mark-release-recapture experiment with adult Anopheles minimus (Diptera: Culicidae) on Ishigaki Island, Ryukyu Archipelago, Japan.

Movement of adult An. minimus Theobald between larval habitats and feeding sites was investigated by mark-release-recapture in March 1993 on Ishigaki Island, Ryukyu Archipelago, Japan. Unfed (998 females) and fed (1,485 females) cohorts from a laboratory colony were marked with different colors of fluorescent dye, and released near Nishihama stream where larvae were abundant. Overall, 42 fed (2.82%) and 13 unfed (1.30%) females were recaptured. Among these, 12 females were recaptured at a cowshed, the nearest blood meal source. Most females in the fed cohort recaptured at the release point had developing or matured ovaries, whereas 55% at the cowshed were parous. The movement of released females from larval habitat to the cowshed for blood feeding indicated a flight distance > 1 km.

Animals↗
PubMed1999

Oxidative stress causes enhanced endothelial cell injury in human heme oxygenase-1 deficiency.

The first known human case of heme oxygenase-1 (HO-1) deficiency is presented in this report. The patient is a six-year-old boy with severe growth retardation. He has been suffering from persistent hemolytic anemia characterized by marked erythrocyte fragmentation and intravascular hemolysis, with paradoxical increase of serum haptoglobin and low bilirubin. An abnormal coagulation/fibrinolysis system, associated with elevated thrombomodulin and von Willebrand factor, indicated the presence of severe, persistent endothelial damage. Electron microscopy of renal glomeruli revealed detachment of endothelium, with subendothelial deposition of an unidentified material. Iron deposition was noted in renal and hepatic tissue. Immunohistochemistry of hepatic tissue and immunoblotting of a cadmium-stimulated Epstein-Barr virus-transformed lymphoblastoid cell line (LCL) revealed complete absence of HO-1 production. An LCL derived from the patient was extremely sensitive to hemin-induced cell injury. Sequence analysis of the patient's HO-1 gene revealed complete loss of exon-2 of the maternal allele and a two-nucleotide deletion within exon3 of the paternal allele. Growth retardation, anemia, iron deposition, and vulnerability to stressful injury are all characteristics observed in recently described HO-1 targeted mice. This study presents not only the first human case of HO-1 deficiency but may also provide clues to the key roles played by this important enzyme in vivo.

Animals↗
PubMed1999

Age-dependent increase of IgE-binding and FcepsilonRI expression on circulating basophils in children.

Peripheral blood basophils are sparse in the circulation, but they express high-affinity receptors for IgE (FCepsilonRI) and bind IgE efficiently. The present study was performed to elucidate the role of IgE bound on the basophil surface in the development of allergic responses during infancy and early childhood. IgE-binding and FcepsilonRI expression on basophils were evaluated by two-color flow cytometry. Basophil-bound IgE increased rapidly and reached adult levels during infancy in atopic patients, while it gradually increased with advancing age in parallel with serum IgE in normal controls. IgE-binding and FcepsilonRI expression in atopic children were higher than in normal controls among various age groups. They correlated with serum IgE levels but reached a plateau when serum IgE exceeded 300 ng/mL. A low, but significant level of FcepsilonRI expression was observed on cord blood basophils, although IgE-binding was usually undetectable. Incubation of cord blood with IgE rapidly saturated the preexisting IgE receptors and basophil-bound IgE levels increased. When neonatal basophils were cultured for 48 h with IgE, FcepsilonRI expression was upregulated dose-dependently and IgE-binding increased further. The up-regulation of FcepsilonRI was completely inhibited by cycloheximide, indicating that it was dependent on de novo protein synthesis. These results suggest that IgE-binding on basophils serves as a sensitive indicator of allergic sensitization, and that IgE functions as a positive regulator of FcepsilonRI expression in vivo.

Adolescent↗
PubMed1997

Description of Topomyia irianensis n. sp. and new records of To. papuensis from Maluku and Irian Jaya, Indonesia (Diptera:Culicidae).

The adults, male genitalia, pupa, and larva of Topomyia (Topomyia) irianensis n. sp. from Irian Jaya, Indonesia, are described and illustrated. The new species is compared to closely related species, Topomyia dejesusi Baisas and Feliciano, 1953, and Topomyia argyropalpis Leicester, 1908. Topomyia (Suaymyia) papuensis Marks was recorded for the first time from Maluku and Irian Jaya. This is the first record of the genus Topomyia from Maluku and Irian Jaya, Indonesia.

Animals↗
PubMed1997

Breeding habitats of Aedes aegypti (L) and Aedes. albopictus (Skuse) in villages of Barru, South Sulawesi, Indonesia.

The breeding habitats of the dengue vector, Aedes aegypti and Aedes albopictus, were studied using larval collection method inside and outside houses in 6 villages of Barru, South Sulawesi, Indonesia from July 1994 to August 1995. Aedes aegypti was the dominant species, being abundant indoors especially in the coastal areas. Aedes albopictus was breeding primarily in outdoor containers in the hill and mountain areas. Earthen jar was the most common breeding habitat of Aedes aegypti in all villages surveyed. Drum can was the most common outdoor breeding habitat of Aedes albopictus in the hill and mountain areas. The high Breteau indices of Aedes aegypti and Aedes albopictus suggests that these species may play an important role in the transmission of dengue hemorrhagic fever in Barru where epidemics of the fever occur occasionally.

Adolescent↗
PubMed1996

Occurrence of Aedes (Stegomyia) spp. mosquitoes (Diptera: Culicidae) in Halmahela villages, Indonesia.

Aedes (Stegomyia) spp. mosquitoes breeding in containers in and around human houses were surveyed in Halmahela villages, the North Moluccas, Indonesia. Adults reared from larvae found in containers and those reared from eggs collected by ovitraps revealed the dominance of Aedes scutellaris (Walker) in residential areas. Breeding of Aedes aegypti (L.) and Aedes albopictus (Skuse) was confirmed in a few coastal villages with high human densities.

Aedes↗
PubMed1996

Diurnal changes in leaf gas exchange characteristics in the uppermost canopy of a rain forest tree, Dryobalanops aromatica Gaertn. f.

Dryobalanops aromatica Gaertn. f. is a major tropical canopy species in lowland tropical rain forests in Peninsular Malaysia. Diurnal changes in net photosynthetic rate (A) and stomatal conductance to water vapor (g(s)) were measured in fully expanded young and old leaves in the uppermost canopy (35 m above ground). Maximum A was 12 and 10 micro mol m(-2) s(-1) in young and old leaves, respectively; however, because of large variation in A among leaves, mean maximum A in young and old leaves was only 6.6 and 5.5 micro mol m(-2) s(-1), respectively. Both g(s) and A declined in young leaves when T(leaf) exceeded 34 degrees C and leaf-to-air vapor pressure deficit (DeltaW) exceeded 0.025, whereas in old leaves, g(s) and A did not start to decline until T(leaf) and DeltaW exceeded 36 degrees C and 0.035, respectively. Under saturating light conditions, A was linearly related to g(s). The coefficient of variation (CV) for the difference between the CO(2) concentrations of ambient air and the leaf intercellular air space (C(a) - C(i)) was smaller than the CV for A or g(s), suggesting that maximum g(s) was mainly controlled by mesophyll assimilation (A/C(i)). Minimum C(i)/C(a) ratios were relatively high (0.72-0.73), indicating a small drought-induced stomatal limitation to A and non-conservative water use in the uppermost canopy leaves.

Journal Article↗
PubMed1996

[Assessment by flow cytometric method of IgE-binding state of basophils in allergic disorders].

Basophils, as well as mast cells, express Fc epsilon RI on the surface. It is known that activation of basophils and mast cells leads to induction of chronic allergic inflammation. In this study, levels of IgE bound to the surface of peripheral blood basophils were measured using a flowcytometry, and their clinical relevance was evaluated. Peripheral whole blood samples were stained with FITC-conjugated anti-IgE. The fluorescence intensity of the FITC-positive cells within mononuclear cell region was determined. Basophil-bound IgE levels increased along with age and reached invariably high levels of adults. The levels of basophil-bound IgE were higher among allergics than normal controls, in early infancy. In addition, many of the infants with repeated wheezing episodes also exhibited high levels of it. These findings suggest that early exposure of predisposed infants to antigens leads to early sensitization of circulating basophils. Basophil-bound IgE levels correlated well with serum IgE concentration, but they remained constant when IgE concentrations exceeded 300 ng/ml, suggesting that IgE-binding capacity of basophils become saturated at this IgE level. In conclusion, it is shown that flowcytometric measurement of basophil-bound IgE provides a useful method of analyzing this rare cell population within the peripheral circulation, and it serves as a critical parameter to evaluate the allergic inflammation in vivo.

Adolescent↗
PubMed1996

[Survey of allergic diseases in 3-year old children in Okinawa City].

A questionnaire survey was conducted between September 1993 and March 1994 to ascertain the presence of allergic diseases among 3-year old children in Okinawa City of Okinawa Prefecture. Nine hundred and twenty-two questionnaires were sent to caretakers of 3-year old children, with 697 responses of which five invalid cases were deleted for a total of 692 responses which were analyzed. About 30% of these children had allergic diseases as diagnosed by the medical doctor. Among the respondents 15.1% had experience of atopic dermatitis, while 13.9% had experience of asthma. The incidence of atopic dermatitis in this survey was lower than those reported in other prefectures of Japan. Symptoms for atopic dermatitis were more severe during summer. About 15% of the children had been on a diet regimen for prevention or treatment of allergic diseases since the time of conception. Eighteen percent of the respondents used a vacuum cleaner on their bedding. A high proportion of respondents (65.9%) obtained information from newspapers or magazines about allergic diseases.

Asthma↗
PubMed1996

Historical review of mosquito control as a component of malaria eradication program in the Ryukyu Archipelago.

In the Ryukyu Archipelago, where malaria used to be endemic, eradication of the disease was achieved by the year 1962, as a consequential effect of a planned malaria eradication program in the area. This achievement was facilitated by concerted efforts in controlling vector mosquitos and treatment of all detected and presumptive cases of malaria infections. Anopheles minimus Theobald and An. sinensis Wiedemann were common in all areas endemic for malaria. Knowledge of the biology and bionomics of the mosquitos in malaria endemic areas formed the basis for formulating strategies for the control of vectors and subsequent surveillance activities. Insecticide residual spray, larvivorous fishes and environmental management were the basic strategies for vector control. The whole program was augmented by an active community participation in all eradication activities.

History, 19th Century↗
PubMed1995

Mosquito (Diptera: Culicidae) and predator abundance in irrigated and rain-fed rice fields in north Sulawesi, Indonesia.

Immature mosquito species composition and abundance were studied in irrigated and rain-fed rice fields of North Sulawesi, Indonesia. Irrigated rice fields were characterized by the prevalence of aquatic macrophytes and cyprinodont larvivorous fish, Aplocheilus panchax (Hamilton), but abundance per dip of most aquatic insect predators was lower than that in rain-fed rice fields. Anopheles peditaeniatus (Leicester), Culex vishnui Theobald, and Culex tritaeniorhynchus Giles, were dominant in both irrigated and rain-fed fields, but the abundance of the Culex species was lower in irrigated fields. The effect of irrigation system introduction on regional mosquito abundance cannot be evaluated by the enlarged surface water area alone. Changes in habitat quality, expressed as the abundance per dip (index of density per unit water area), also need to be considered.

Aedes↗
PubMed1995

Age structure of Anopheles subpictus (Diptera:Culicidae) collected by a light trap in Halmahela, Indonesia.

Age structure of Anopheles subpictus Grassi was studied at a Halmahela village, Indonesia. Ovary development of females reared with 2% sugar solution after emergence ceased at Stage I and their ovary size remained small (mean length x width = 0.68 x 0.18 mm). Females with such small ovaries occupied 21.2% of unfed Stage I females in cattle-bait samples. The remaining unfed Stage I or II females had cleary larger ovaries (mean 1.17 x 0.39 mm). Unfed Stage I or II females collected by the outdoor light trap all had large ovaries (mean 1.42 x 0.34 mm) irrespective of stages and parity. The parous rate of unfed stage I or II females collected by the light trap (86.6%) was significantly higher than that of cattle-bait samples (69.6%). Feasibility of using outdoor light trapping in malaria entomology was discussed.

Age Distribution↗
PubMed1994

Prevalence of intestinal helminthic infections in Kao District, north Halmahera, Indonesia.

A parasitological survey was conducted on the inhabitants of six villages of Kao District, Halmahera Island, North Maluku, Indonesia, in July 1993. A total of 422 fecal samples were examined by using Kato-Katz thick smear, modified Harada-Mori culture and formalin ether concentration techniques. Seven nematode species, ie Ascaris lumbricoides, Trichuris trichiura, Necator americanus, Ancylostoma duodenale, Strongyloides stercoralis, Enterobius vermicularis and unidentified rhabditoids of free-living nature, were detected. Trematode and cestode infection was not proven. Necator americanus was the predominant species of hookworm. Soil-transmitted nematode infections were highly prevalent. Among the young inhabitants aged less than 15, positive rates of Ascaris, Trichuris and hookworm infections were 32.7, 52.7 and 68.6%, respectively. Among the people aged 15 or more, the positive rate for hookworm (85.9%) was much higher than that for Ascaris and Trichuris (13.5 and 40.5%, respectively). Egg count revealed that more than 90% of inhabitants with Trichuris or hookworm had light infections. The latrines in the surveyed area seemed to have only limited effects on the improvement of the parasitological status because the prevalence of Trichuris infections was much higher in a village where most houses were provided with latrines. These conflicting conditions were considered to have been caused by many factors including the inadequate structure of the latrines.

Adolescent↗
PubMed1993

[Expression of surface CD11b antigen and eosinophil activation].

Recent evidences suggest that the expression of adhesion molecules on eosinophils and endothelial surface play pivotal roles in the migration of activated eosinophils to the site of allergic inflammation. Among these, CD11b/ICAM-1 system is known to be responsible for at least part of the eosinophil/endothelial adhesion. CD11b expression on the surface of circulating eosinophils is significantly elevated in various allergic disorders, including atopic dermatitis and bronchial asthma. Various eosinophilopoietic cytokines, including IL-3, IL-5 and GM-CSF induced rapid upregulation of CD11b expression on eosinophils in vitro. These observations suggest that surface CD11b may serve as a useful parameter of eosinophil activation and may reflect the in vivo level of eosinophilopoietic cytokines.

Cell Adhesion Molecules↗
PubMed1993

Intestinal parasitic infections in Campalagian district, south Sulawesi, Indonesia.

Intestinal parasitic infections were surveyed in the inhabitants of 3 coastal and 2 inland villages of Campalagian District, South Sulawesi, Indonesia, in July 1992. A total of 398 fecal samples were examined by using Kato-Katz thick smear, Harada-Mori culture and agar-plate culture techniques. Protozoan cysts were examined by formalin ether concentration technique on 380 fecal samples. Soil-transmitted helminth infections were highly prevalent with the overall positive rates as follows: Ascaris lumbricoides 25.3%, Trichuris trichiura 59.3%, hookworm 68.3% and Strongyloides stercoralis 2.3%. Eight species of protozoan were detected with the overall prevalence as follows: Entamoeba histolytica 10.9%, E. hartmanni 16.3%, E. coli 31.9%, Endolimax nana 12.5%, Iodamoeba buetschlii 5.4%, Giardia lamblia 4.6%, Chilomastix mesnili 0.8% and Blastocystis hominis 18.0%. In the inland villages, prevalence of hookworm infection was higher than Ascaris and Trichuris infections, while in the coastal villages Trichuris infection was predominant. Egg count revealed that the infection level was light in most of the hookworm and Trichuris carriers. Prevalence of lavatories among houses appeared to be inversely proportional to the prevalence of hookworm infection. Meanwhile, the incomplete structure of the lavatories might result in contamination of environment with Ascaris and Trichuris eggs. Harada-Mori culture was the most efficient method in the detection of hookworm infection compared to other techniques. Both Necator americanus and Ancylostoma duodenale were found in all villages, but the former was the predominant species. An adult pinworm was detected by agar-plate culture of feces. Two types of pinworm males, corresponding to Enterobius vermicularis and E. gregorii, were observed.

Adolescent↗