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31.
32.
Background

Sickle haemoglobin (HbS) is known to offer considerable protection against falciparum malaria. However, the mechanism of protection is not yet completely understood. In this study, we investigate how the presence of the sickle cell trait affects the haematological profile of AS persons with malaria, in comparison with similarly infected persons with HbAA. This study is based on the hypothesis that the sickle cell trait plays a protective role against malaria.

Methods

Children from an endemic malaria transmission area in Yemen were enrolled in this study. Hematological parameters were estimated using manual methods, the percentage of parasite density on stained thin smear was calculated, haemoglobin genotypes were determined on paper electrophoresis, ferritin was measured using enzyme-linked immunosorbent assay, serum iron and TIBC were assayed using spectrophotometer, transferrin saturation index was calculated by dividing serum iron by TIBC and expressing the result as a percentage. Haematological parameters were compared in HbAA- and HbAS-infected children.

Results

Falciparum malaria parasitaemia was confirmed in the blood smears of 62 children, 44 (55.7%) of AA and 18 (37.5%) AS, so there was higher prevalence in HbAA children (P = 0.047). Parasite density was lower in HbAS- than HbAA-infected children (P = 0.003). Anaemia was prominent in malaria-infected children, with high proportions of moderate and severe forms in HbAA (P = 0.001). The mean levels of haemoglobin, packed cell volume, reticulocyte count, platelets count, lymphocytes, eosinophils, and serum iron were significantly lower while total leukocytes, immature granulocytes, monocytes, erythrocyte sedimentation rate, transferrin saturation, and serum ferritin were significantly higher in HbAA-infected children than HbAS-infected children.

Conclusion

Infection with Plasmodium falciparum malaria caused more significant haematological alterations of HbAA children than HbAS. This study supports the observation that sickle cell trait seems to be a beneficial genetic factor that resists malaria, since inheriting it protects against significant haematological consequences of malaria.  相似文献   

33.

Background

Schistosomiasis and soil transmitted infection is a major health problem of children from rural areas of developing countries including Yemen. In an attempt to reduce this burden, the Ministry of Public Health and Population in Yemen established in 2002 a programme for Schistosomal, soil transmitted infection control that aimed to reduce morbidity and prevalence rates of Schistosomiasis, and Soil transmitted helminthes to less than 5% by 2015. The study was conducted to assess the current prevalence and intensity of schistosomal infection among schoolchildren in rural areas of the Taiz governorate after 6 years of running National Control Programme.

Methods

Grade 3 schoolchildren from Shara''b Al-Raona district of Taiz Governorate were examined for infections with Schistosoma mansoni using Modified Kato–Katz method and S. haematobium applying filtration method in 1998/1999, comparing the prevalence and intensity of infection with base line study, which was done 6 years ago.

Results

The S. mansoni prevalence in the study population was 31%, while the prevalence of S. haematobium was 18.6%. This result considerably is similar to the prevalence of base line study. The intensity of mild, moderate and severe infection for S. mansoni reached to 15.9%, 60.6% & 23.5% respectively. The severity of S. haematobium infection was 68.4%. It was exceptionally found that the prevalence of S. haematobium is increased.

Conclusion

The high prevalence of schistosomiasis and low effectiveness of control programme against schistosomal infection in the study area demands consideration of alternative treatment approaches.  相似文献   
34.

Objective

No evidence-based data exist on the availability, accessibility and utilization of healthcare services in Lahej Governorate, Yemen. The aim of this study was to assess the distribution and utilization of curative services in primary healthcare units and centres in Lahej.

Study design

Cross-sectional study (clustering sample).

Method

This study was conducted in three of the 15 districts in Lahej between December 2009 and August 2010. Household members were interviewed using a questionnaire to determine sociodemographic characteristics and types of healthcare services available in the area.

Results

The distribution of health centres, health units and hospitals did not match the size of the populations or areas of the districts included in this study. Geographical accessibility was the main obstacle to utilization. Factors associated with the utilization of curative services were significantly related to the time required to reach the nearest facility, seeking curative services during illness and awareness of the availability of health facilities (P < 0.01).

Conclusion

There is an urgent need to look critically and scientifically at the distribution of healthcare services in the region in order to ensure accessibility and quality of services.  相似文献   
35.
《Pharmaceutical biology》2013,51(2):200-210
Context: The role of natural products as a source for remedies has been recognized since the beginning of mankind. Nevertheless, a minority of folkloricly used medicinal plants have been evaluated for their pharmacological activities.

Objectives: The purpose of this study is to evaluate 33 selected Yemeni plants for their in vitro anticancer, antimicrobial, and antioxidant activities.

Materials and methods: The plants were extracted with methanol and hot water. The obtained 66 extracts were tested for their in vitro cytotoxic activity using the neutral red uptake assay against two cancer cell lines (5637 and MCF-7). The antimicrobial activity was determined using the agar diffusion method and MIC-determination. The DPPH radical method was used for the determination of antioxidant activity.

Results: Interesting cytotoxic activity was observed for Hypoestes forskalei (Vahl) R. Br. (Acanthaceae), Lycium shawii Roem. & Schult. (Solanaceae), Pergularia tomentosa L. (Asclepiadaceae), Psiadia punctulata (DC.) Vatke (Compositae), Pulicaria petiolaris Jaub. & Spach (Compositae) and Rosmarinus officinalis L. (Labiatae) (IC50 values < 50 μg/mL). Antimicrobial activity with MIC values ≤ 125 μg/mL was exhibited against Gram-positive bacteria by Chrozophora oblongifolia (Del.) A.Juss. ex Spreng. (Euphorbiaceae), Myrtus communis L. (Myrtaceae), Phragmanthera regularis (Steud. ex Sprague) M.G. Gilbert (Loranthaceae) and R. officinalis. Antioxidant activity was observed for C. oblongifolia, M. communis, and P. regularis.

Conclusion: The results justified the use of some investigated plants in the Yemeni ethnomedicine. These findings demonstrated that some of the investigated plants could be a source of new cytotoxic and antibiotic compounds; however, further work is needed.  相似文献   
36.
Background: Oral cancer presents with high mortality rates, and the likelihood of survival is remarkablysuperior when detected early. Dental professionals have an important role and responsibility in prevention andearly detection of oral cancer. Purpose: The aim of this study was to assess the knowledge, practices and opinionsregarding oral cancer among dentists in Yemen. Materials and Methods: A cross-sectional survey was conductedusing a self-administered questionnaire involving private and public dental practitioners, working in differentgovernorates in Yemen. Results: Of the 800 dentists surveyed, a total of 221 questionnaires were completed andreturned (response rate 27.6%). A vast majority of dentists (96.38%) identified tobacco as the major risk factorfor oral cancer, and 82.8% knew that squamous cell carcinoma is the most common form. While 47.1% of thedentists agreed that they were adequately trained in oral cancer screening, the majority (86%) believed that theyneed further training in oral cancer screening. Conclusions: These results suggest that additional training andcontinuing educational programs on prevention and early detection of oral cancer for dentists are to be highlyrecommended.  相似文献   
37.
The traditional medicine still plays an important role in the primary health care in Yemen. The current study represents the investigation of 16 selected plants, which were collected from different localities of Yemen. The plants were dried and extracted with two different solvents (methanol and hot water) to yield 34 crude extracts. The obtained extracts were tested for their antimicrobial activity against three Gram-positive bacteria, two Gram-negative bacteria, one yeast species and three multiresistant Staphylococcus strains using agar diffusion method, for their antioxidant activity using scavenging activity of DPPH radical method and for their cytotoxic activity using the neutral red uptake assay. In addition, a phytochemical screening of the methanolic extracts was done. Antibacterial activity was shown only against Gram-positive bacteria, among them multiresistant bacteria. The highest antimicrobial activity was exhibited by the methanolic extracts of Acalypha fruticosa, Centaurea pseudosinaica, Dodonaea viscosa, Jatropha variegata, Lippia citriodora, Plectranthus hadiensis, Tragia pungens and Verbascum bottae. Six methanolic extracts especially those of A. fruticosa, Actiniopteris semiflabellata, D. viscosa, P. hadiensis, T. pungens and V. bottae showed high free radical scavenging activity. Moreover, remarkable cytotoxic activity against FL-cells was found for the methanolic extracts of A. fruticosa, Iris albicans, L. citriodora and T. pungens. The phytochemical screening demonstrated the presence of different types of compounds like flavonoids, terpenoids and others, which could be responsible for the obtained activities.  相似文献   
38.
INTRODUCTION: Fusobacterium nucleatum represents one of the predominant anaerobic species in the oral microbiota. Penicillin-resistant F. nucleatum have been isolated from intra- and extraoral infections. This study aimed to assess ampicillin resistance in F. nucleatum by investigating the synthesis of resistance-associated proteins. METHODS: Ampicillin-resistant and ampicillin-susceptible F. nucleatum isolates were obtained from 22 dental plaque samples. Two-dimensional gel electrophoresis and mass spectrometry were used to investigate bacterial protein synthesis. Proteins exhibiting statistically significant quantitative changes between sensitive and resistant isolates were identified using peptide mass mapping and matrix-assisted laser desorption/ionization - time of flight/time of flight (MALDI-TOF/TOF) mass spectrometry. RESULTS: Twenty-three F. nucleatum isolates were recovered from plaque samples and their ampicillin minimum inhibitory concentrations ranged between 0.125 microg/ml and 256 microg/ml. Analysis of the bacterial cellular proteins by two-dimensional gel electrophoresis resolved 154-246 distinct protein spots (mean 212, n = 9). Between 32% and 83% of the protein spots were common for the F. nucleatum isolates. Comparisons of the protein profiles of sensitive and resistant isolates revealed the presence of a 29 kDa protein and significant increases in the synthesis of two proteins at 37 and 46 kDa in the ampicillin-resistant F. nucleatum isolates. These proteins were identified as a class D beta-lactamase, ATP-binding cassette (ABC) transporter ATP-binding protein and enolase, respectively. CONCLUSION: Synthesis of a class D beta-lactamase by ampicillin-resistant F. nucleatum isolates could complicate antimicrobial treatment because these enzymes might confer resistance to many classes of beta-lactam antibiotics. The differences observed in protein synthesis between ampicillin-resistant and ampicillin-susceptible F. nucleatum may contribute to the antibiotic resistance and virulence of these bacteria.  相似文献   
39.
40.
Background: Breast cancer is the most common cancer of women and the principal cause of death in middleaged women. The objective of this study was to describe the trend of breast cancer and its management in Adenand adjacent south-eastern governorates of Yemen during the last 20 years. Patients and Methods: This is aretrospective analysis of previous studies on patients with breast cancer in Aden and adjacent south-easterngovernorates, Yemen (January 1989 through December 2007). The studied variables were: sex, age, time andtype of presentation, disease stage, pathological types and the performed surgical treatment. The sources ofinformation were the treatment registry of Aden health office, archives of Al-Gamhouria teaching hospital; majorreferral and other public and private hospitals in Aden and Aden Cancer Registry. Results: The total numberof patients was 476, 99% being females. The age range was 19-88 years. The most affected age was 30-50 years(60.5%), 95% presenting after one month of having breast symptoms. Forty-five percent presented with signsof advanced local disease, while 59.2% had palpable axillary lymph nodes on presentation. Early breast cancer(stages I-II) occurred in 47%, and late breast cancer (stages III-IV) in 51.5%. Invasive ductal carcinoma was thecommonest pathology (89.3%). The main surgical treatment was mastectomy (modified radical mastectomy(50%). Conclusion: Breast cancer is predominantly a disease of young with late presentation and advanceddisease. Improving health awareness and earlier diagnosis of the disease by health education, encouragingbreast self-examination, and providing the mammography equipment and mammary clinics in hospitals arerecommended. Establishment of oncology and radiotherapy centers in Aden is a necessity.  相似文献   
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