Effects of a food supplement rich in arginine in patients with smear positive pulmonary tuberculosis--a randomised trial.

In tuberculosis (TB), the production of nitric oxide (NO) is confirmed but its importance in host defense is debated. Our aim was to investigate whether a food supplement rich in arginine could enhance clinical improvement in TB patients by increased NO production. Smear positive TB patients from Gondar, Ethiopia (n = 180) were randomized to a food supplementation rich in arginine (peanuts, equivalent to 1 g of arginine/day) or with a low arginine content (wheat crackers, locally called daboqolo) during four weeks. The primary outcome was cure rate according to the WHO classification and secondary outcomes were sputum smear conversion, weight gain, sedimentation rate, reduction of cough and chest X-ray improvement as well as levels of NO in urine (uNO) or exhaled air (eNO) at two months. There was no effect of the intervention on the primary outcome (OR 1.44, 95% CI: 0.69-3.0, p = 0.39) or secondary outcomes. In the subgroup analysis according to HIV status, peanut supplemented HIV+/TB patients showed increased cure rate (83.8% (31/37) vs 53.1% (17/32), p < 0.01). A low baseline eNO (<10 ppb) in HIV+/TB patients was associated with a decreased cure rate. We conclude that nutritional supplementation with a food supplement rich in arginine did not have any overall clinical effect. In the subgroup of HIV positive TB patients, it significantly increased the cure rate and as an additional finding in this subgroup, low initial levels of NO in exhaled air were associated with a poor clinical outcome but this needs to be confirmed in further studies.

Photodegradation of melanin by an interferometric technique.

Photodegradation of melanin thin films is investigated for a UVA wavelength of 355 nm and a UVC wavelength of 244 nm. The technique involves interferometric exposure of melanin with two coherent beams from a low-power UV laser. The periodic photodegradation-grating pattern is monitored by diffraction of a second low-power He-Ne laser. Dependence of the photodegradation rate on UV intensity as well as the effect of ambient humidity is investigated and explained with a simple model. The technique has promise for investigating photo-induced effects in other biomolecular substrates as well.

Effect of Ethiopian multiflora honey on fluconazole-resistant Candida species isolated from the oral cavity of AIDS patients.

This study aimed to determine the antifungal effect of Ethiopian multiflora honey against Candida species isolated from the oral cavity of AIDS patients. Oral rinses were obtained from 13 AIDS patients and cultured on CHROMagar plates at 37°C for 48 hours. Candida species were identified by microbiological and molecular techniques. The antifungal effect of the honey sample on Candida was investigated by an agar dilution technique. Susceptibility of the Candida species to fluconazole was tested following a semi-modified microdilution method. Growth of both fluconazole-susceptible and -resistant Candida species was inhibited with a minimum fungicidal concentration (MFC) of 35-40% (v/v) honey. The MFC of different Candida species was not significantly different (P > 0.05). From the total of 25 Candida isolates tested for susceptibility, 11 (44%), eight (32%) and six (24%) of the isolates were sensitive (minimum inhibitory concentrations [MICs] < 8 µg/mL), susceptible (dose-dependent: MICs 16-32 µg/mL) and resistant (MICs > 64 µg/mL) to fluconazole, respectively. Ethiopian multiflora honey has antifungal activity against fluconazole-resistant Candida species isolated from the oral cavity of AIDS patients. This supports the existing folkloric practice of using honey to treat oral lesions. Nevertheless, identification of the bioactive agents in honey, their clinical evaluation and pharmacological standardization are crucial.

Photochemically deposited surface relief gratings of an azo-dye-labeled phospholipid from the aqueous phase.

Surface relief holographic gratings are fabricated on the polybutadiene-coated walls of a cell filled with an aqueous solution of an azo-dye-labeled phospholipid. A low power (2 mW) 488 nm argon ion laser wavelength is used. Laser-excited azo dye reacts to produce a permanent surface-relief pattern on the polybutadiene substrate. Gratings are recorded for varying concentrations of the phospholipid solution as well as laser intensity. Lithographic masks are used to show that the photochemical pattern on the substrate is an exact replica of the light intensity distribution, and so the technique can be used for holographic recording as well as for biomolecular applications.

Resting metabolic rate of Vietnamese adolescents.

OBJECTIVE: To evaluate the FAO/WHO/UNU equations for predicting resting metabolic rate (RMR) in Vietnamese adolescents. DESIGN: A cross-sectional study involving healthy subjects was carried out at the Basic Nutrition Department, National Institute of Nutrition, Vietnam. The RMR was measured by indirect calorimetry and anthropometric indices were recorded. Equations derived by linear regression of RMR and body weight were compared to the FAO/WHO/UNU (1985) predictive equations. SUBJECTS: A total of 110 subjects who had normal body mass index (5-85 percentile) and divided into two groups by sex. RESULTS: Mean RMRs (MJ/kg/day) were 0.1146+/-0.0054 for males and 0.1062+/-0.0103 for females. Compared to the FAO/WHO/UNU equation, our findings were 7.8% and 11.7% lower in the two groups, respectively (P<0.001). CONCLUSION: Our findings suggest that the FAO/WHO/UNU equations may overestimate RMR in Vietnamese adolescents. Further studies on establishing reference of daily energy needs for Vietnamese adolescents should be carried out.

Fabrication and characterization of a diffraction-grating transducer in thin polybutadiene rubber film for sensing dynamical strain.

Surface relief gratings are holographically fabricated in thin polybutadiene rubber films produced by both spin coating and dip coating on glass and metal substrates. These thin-film gratings are characterized for their application as efficient transducers for detecting dynamic strain in solids. The performance of these rubber-grating transducers is compared to surface-mounted fiber Bragg gratings for a range of frequencies between 50 Hz and 30 kHz. Dynamic-strain sensitivity around 1 nepsilon/radicalHz is recorded for thin rubber-film grating transducers.

Photopatterning in poly-L-lysine thin films using UV-enhanced hydrophilicity.

Deep UV lithography on poly-L-lysine thin films was used to generate microarrays with enhanced hydrophilicity. This was manifested as adsorption of ambient humidity from air by areas exposed to UV fluence around 5 J/cm2 and was made visible by phase-contrast microscopy. Kinetics of adsorption was investigated by a novel technique involving fabrication of submicrometer hydrophilicity grating by two-beam UV interferometry. In an aqueous colloidal medium, gold and polystyrene microspheres preferentially attach to areas that are relatively less hydrophilic, i.e., those areas not exposed to UV light. This observation provides a method for fabricating micro- and nanoporous arrays with controlled porosity. The technique is demonstrated with microspheres of sizes between 250 nm and 10 microm.

Alterations in serum levels of trace elements in tuberculosis and HIV infections.

OBJECTIVE: To evaluate serum concentrations of trace elements in tuberculosis (TB) patients with or with out human immunodeficiency virus (HIV) coinfection before and after anti-TB chemotherapy. SUBJECTS: A total of 155 TB patients, 74 of which were coinfected with HIV, and 31 healthy controls from Gondar, Ethiopia. METHODS: Serum levels of copper, zinc, selenium and iron were determined using an inductively coupled plasma mass spectrometer from all subjects at baseline and from 44 TB patients (22 with HIV coinfection) at the end of an intensive phase of anti-TB chemotherapy. RESULTS: Compared with the control group, the concentrations of iron, zinc and selenium were significantly lower (P<0.05) while that of copper and copper/zinc ratio was significantly higher (P<0.05) in the serum of TB patients. TB patients with HIV coinfection had significantly lower serum zinc and selenium concentrations and significantly higher copper/zinc ratio compared to that in TB patients without HIV coinfection (P<0.05). The serum concentration of zinc had significantly increased at the end of intensive phase of anti-TB chemotherapy in patients without HIV coinfection (P<0.05). An increase in serum selenium level was observed in TB patients with or without HIV coinfection after therapy. On the contrary, serum copper concentration and copper/zinc ratio declined significantly after anti-TB chemotherapy irrespective of HIV serostatus (P<0.05). CONCLUSIONS: The results indicate that TB patients have altered profile of trace elements in their sera. This warrants the need for further investigations so that strategies for trace elements supplementation can be planned in addition to their potential as diagnostic parameters in monitoring responses to anti-TB chemotherapy.

Serological diversity demonstrable by a set of monoclonal antibodies to eight serotypes of the mutans streptococci.

A set of monoclonal antibodies were prepared by the conventional cell fusion of myeloma cells (SP2/0-Ag14) with spleen cells from BALB/c mice immunised with whole cells of a strain of mutans streptococci. Their specificities were examined against 35 reference strains of mutans streptococci, 34 reference strains of other oral streptococci and 8 reference strains of other microorganisms often inhabiting the oral cavity. Specificity was examined by enzyme immunoassay using whole cells. A total of 52 strains, consisting of 19 strains isolated in Japan, 19 strains isolated in Italy and 14 strains isolated in England, were characterised by conventional physiological and biochemical tests and then serotyped by the use of 8 monoclonal antibodies with different specificities. They were also confirmed by guanine-plus-cytosine contents of their nucleic acid and DNA-DNA hybridisation test. The results indicated that all monoclonal antibodies are useful for identification of 8 serotypes of the mutans streptococci responsible for dental caries. They also suggest the existence of more serological varieties among mutans species.

Prevalence of dental caries and sugar consumption among 6-12-y-old schoolchildren in La Trinidad, Benguet, Philippines.

OBJECTIVE: To determine the prevalence of dental caries and the level of sugar consumption among 6-12-y-old schoolchildren in La Trinidad, Benguet, Philippines. DESIGN: A Cross-sectional study as a baseline survey for a later intervention program. A questionnaire was distributed to obtain information on dental history and total consumption of food with sugar. Caries were diagnosed based on the WHO recommendation. RESULTS: A total of 1200 schoolchildren, aged 6-12 y were included. The prevalence of dental caries in primary dentition was 71.7% and in the permanent dentition, 68.2%. The mean total decayed, extracted due to caries and filled primary teeth (DMFT) and decayed, missing and filled permanent teeth (DMFT) were 4.12 (s.d. 4.03) and 2.40 (s.d. 2.57), respectively. As age increased the mean DMFT increased. Majority (70%) had tooth brushing practices, and less than half (42.5%) had a dental visit only when necessary. Their sugar intake was twice more than the WHO recommendation with a mean daily total intake of 59 g per person. Most common sources of dietary sugar were hard candies (89%), banana cue (84.9%), camote cue (84.9%) and soft drinks (84.4%). No significant correlation was found between sugar intake and dental caries. CONCLUSION: The results indicate that dental caries is highly prevalent and increase with augmented sugar consumption. This maybe due to a widespread neglect of oral health and an increased availability of refined sugary products. Caries rates mirrored those of the developing countries with untreated lesions dominating all ages. The high level of untreated caries in all age groups is a cause for concern.

Photoinduced grating formation in azo-dye-labeled phospholipid thin films by 244-nm light.

Holographic gratings are recorded in azo-dye nitrobenzoxazole-labeled phospholipid thin films by use of 244-nm UV light. The gratings continue to grow for more than 1 h, even after the recording light is removed. The diffraction efficiency of these gratings shows extreme sensitivity to humidity and can increase reversibly by 2 orders of magnitude in air that is saturated with water vapor. This effect is related to the unique characteristics of phospholipid molecules that undergo hydration-dependent structural reorganization and self-assembly.

Serum IgE levels of tuberculosis patients in a tropical setup with high prevalence of HIV and intestinal parasitoses.

Tuberculosis remains a major health problem worldwide in the era of HIV/AIDS. Co-infection with intestinal parasites has been suggested to worsen the outcome of infection by polarizing the immune response towards Th2. This study investigated serum IgE levels of 241 tuberculosis patients and compared the IgE profiles in the tuberculosis patients either with or without intestinal helminthic infection and/or HIV infection. The serum levels of IgE in tuberculosis patients before initiation of antimycobacterial chemotherapy were found to be 1722 +/- 1290 IU/ml (Mean +/- SD) in HIV seronegatives and 2366 +/- 1849 IU/ml in HIV seropositives. Further, the IgE level was significantly higher in patients coinfected with intestinal helminthes and HIV compared to those infected with helminthes or without coinfection (P < 0.05). Anti-tuberculosis chemotherapy significantly reduced serum IgE levels in HIV seronegative tuberculosis patients (P < 0.05). These findings might indicate an active role of therapy in shifting the immune response towards Th1 which is crucial for prognosis in tuberculosis patients.

Role of incidental and/or cured intestinal parasitic infections on profile of CD4+ and CD8+ T cell subsets and activation status in HIV-1 infected and uninfected adult Ethiopians.

Intestinal parasitic infections have been suggested to cause persistent immune activation leading to an unbalanced immune state. Such a state has been proposed to be a major factor in the pathogenesis of AIDS in an African context. The present study investigated the effect of incidental parasitic infection and treatment on the profile of T cell differentiation and activation markers on CD4+ and CD8+ T cells from HIV-1 infected and uninfected adult Ethiopians. Cryopreserved PBMCs from 64 subjects (41 HIV-negative and 23 HIV-positive) with follow-up visits at 6-monthly intervals were used to compare the effect of incidental intestinal parasites and their treatment upon T cell subset profiles and activation status. The samples were stained with antibodies to various T cell differentiation and activation markers allowing naive, memory, effector, memory/effector, activated and resting CD4+ and CD8+ T cell subsets to be quantified by triple-colour FACScan. Incidental intestinal parasitic infections resulted in a significant increase in memory CD4+ T cell numbers both in HIV-negative and HIV-positive subjects (P < 0.05). There was also a significant increase in the percentage of CD8+ HLA-DR+ T cells (P < 0.05) in HIV-positive subjects co-infected with parasites. In HIV-negative subjects, a significant decline in activated cells and a significant increase in resting CD8+ T cells (P < 0.05) was observed after treatment for parasites. These data suggest that intestinal parasitic infections could result in the alteration of T cell subset counts and also in the up-regulation of T cell activation markers in peripheral blood. Treatment of parasitic infections showed a tendency to reduce the activation suggesting that, together with other community based intervention strategies, such treatment could be used to down-regulate immune activation and hence protect the host from being easily attacked by HIV.

Distribution of lymphocyte subsets in healthy human immunodeficiency virus-negative adult Ethiopians from two geographic locales.

Immunological values for 562 factory workers from Wonji, Ethiopia, a sugar estate 114 km southeast of the capital city, Addis Ababa, Ethiopia, were compared to values for 218 subjects from Akaki, Ethiopia, a suburb of Addis Ababa, for whom partial data were previously published. The following markers were measured: lymphocytes, T cells, B cells, NK cells, CD4(+) T cells, and CD8(+) T cells. A more in depth comparison was also made between Akaki and Wonji subjects. For this purpose, various differentiation and activation marker (CD45RA, CD27, HLA-DR, and CD38) expressions on CD4(+) and CD8(+) T cells were studied in 60 male, human immunodeficiency virus-negative subjects (30 from each site). Data were also compared with Dutch blood donor control values. The results confirmed that Ethiopians have significantly decreased CD4(+) T-cell counts and highly activated immune status, independent of the geographic locale studied. They also showed that male subjects from Akaki have significantly higher CD8(+) T-cell counts, resulting in a proportional increase in each of the CD8(+) T-cell compartments studied: naïve (CD45RA(+)CD27(+)), memory (CD45RA(-)CD27(+)), cytotoxic effector (CD45RA(+)CD27(-)), memory/effector (CD45RA(-)CD27(-)), activated (HLA-DR(+)CD38(+)), and resting (HLA-DR(-)CD38(-)). No expansion of a specific functional subset was observed. Endemic infection or higher immune activation is thus not a likely cause of the higher CD8 counts in the Akaki subjects. The data confirm and extend earlier observations and suggest that, although most lymphocyte subsets are comparable between the two geographical locales, there are also differences. Thus, care should be taken in extrapolating immunological reference values from one population group to another.

Antimicrobial sensitivity of Neisseria gonorrhoea in Gondar, Ethiopia.

OBJECTIVES: To determine the antimicrobial susceptibility pattern of Neisseria gonorrheae and to obtain epidemiological information on resistance of Neisseria gonorrheae in Gondar town. DESIGN: A cross sectional study. SETTING: Gondar Health Centre. SUBJECTS: One hundred and seventy eight male patients presented with urethral discharge and who volunteered to participate in the study were included. RESULTS: A total of 142 strains of N. gonorrhoeae were isolated from 168 cultures received. The sensitivity of gonococcal isolates ranges from 98.6% to chloramphenicol to 7.7% to cotrimoxazole. Multiple drug resistance was reported in 87.5% of isolates and only four isolates were sensitive to all antibiotics. One strain of N. gonorrheae was resistant to as many as eight antibiotics (tetracycline, penicillin, ampicillin, kanamicin, methicilin, carbenicillin, cotrimoxazole and ceftriaxone). More than eighty five per cent of the isolated strains were penicillinase-producing Neisseria gonorrhoeae (PPNG). CONCLUSION: Gonococcal resistance is a significant public health problem in Gondar region and the drugs recommended for treatment of gonococcal cases by the national sexually transmitted diseases (STDs) control programme need to be revised.

Ethnomedical aspects of the commonly used toothbrush sticks in Ethiopia.

OBJECTIVE: To determine the botanical identity, cytotoxicity, and antibacterial property of the commonly used toothbrush sticks in Ethiopia. SETTING: Research laboratories of the departments of Biology and Chemistry, Addis Ababa University between December 1993 and May 1995. METHODS: The study was performed by purchasing the commonly used toothbrush sticks from street markets in various towns of Ethiopia. Voucher specimens were collected and their botanical identity was determined following floral keys. The toothbrush sticks were ground in a mill and soaked in absolute methanol for 24 hours and filtered. The filtrates were dried in a rotary evaporator and the crude extracts were stored at 4 degrees C. The crude methanol extracts were used to test their antibacterial activity by impregnating into filter paper discs and placing on test plates of Staphylococcus aureus and Bacillus cerues. Their lethality to brine shrimp (Artemia salina) was performed following standard procedures. RESULTS: Twenty different species of plant used as toothbrush were collected and their botanical identity determined. Crude methanol extracts of only Agave sisalana, Birbira and Hypericum revolutum test concentrations up to 500 micrograms/ml showed weak toxicity to brine shrimp. All the extracts showed antibacterial activity against Staphylococcus aureus and Bacillus cereus by agar diffusion method. CONCLUSION: Toothbrush sticks can be used by the vast majority of people who cannot afford buying the commercial toothbrush and toothpaste. The toothbrush sticks may be important for the oral and dental hygiene of the users and hence may be useful in decreasing dental caries. Further studies should focus on the effect of the toothbrush sticks against other common bacteria that are associated with dental diseases.

Laboratory services in health centres within Amhara region, north Ethiopia.

OBJECTIVE: To identify current problems in laboratory services and elicit suggestions from the technicians aimed at improving the services in health centres within Amhara region, north Ethiopia. DESIGN: Cross-sectional study using a pre-tested questionnaire. SETTINGS: Twenty seven health centres in Amhara region, north Ethiopia. PARTICIPANTS: Twenty seven laboratory technicians. RESULTS: Physical facilities were seriously lacking, consisting of only one room in 85.2% of the health centres. Supply of electricity was never continuous. Whereas virtually all the health centres had up to five medical doctors each, laboratory manpower was grossly below the ideal requirement. Over half of the health centres had only one technician each, resulting into heavy workload. Laboratory reagents were insufficient, equipment lacking, and maintenance and repair were not accorded adequate attention. Eighty different tests were offered by the health centres in various combinations. Twenty categories of suggestions were advanced by the respondents. CONCLUSION: There is a great shortage of manpower, equipment, chemicals and other supplies to provide adequate laboratory services in the health centres within the region. Consequently, the laboratories are functioning below capacity.

Pattern of outpatient laboratory service consumption in a teaching hospital in Gondar, Ethiopia.

A one year laboratory service analysis for outpatient service consumers of Gondar College of Medical Sciences Hospital was done. Data were gathered through a daily registry prospectively. 17,471 patients visited the laboratory between October 1994 and September 1995. 47.9% were from Gondar town. 72.5% paid for the services. Children under 15 made up only 11.8% of service consumers. In the year, a total of 27,982 laboratory tests were requested, 48% of which were in urinalysis and parasitology. Most of the requests could be handled by upgraded peripheral laboratories leaving room for the unit to act as a training and back-up centre.