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1.
Gangliosides of cultured astroglia 总被引:3,自引:0,他引:3
Michele Sbaschnig-Agler Henri Dreyfus William T. Norton Monique Sensenbrenner Muhammad Farooq Mary C. Byrne Robert W. Ledeen 《Brain research》1988,461(1):98-106
Cultured astrocytes prepared from newborn rat brain and 13-day-old chick embryonic brain were analyzed qualitatively and quantitatively for ganglioside content. All preparations contained approximately the same total level: 2.4-3.4 micrograms N-acetylneuraminic acid (NeuAc)/mg protein. In contrast, the value for primary cultures of neurons from chick embryonic brain was 5.9. The non-hexosamine-containing species, GM3 and GD3, comprised 75-85% of the total in astroglial cultures, the remainder consisting mainly of structural types other than the gangliotetraose series; choleragenoid assay revealed the latter to be virtually absent or to comprise at most a few percent. Deficiency of gangliotetraose synthesizing ability was indicated by the very low level of UDP-GalNac:GM3 N-acetylgalactosaminyltransferase detected in the cells. Treatment of cultured astrocytes with astroglial growth factor 2 or dibutyryl cyclic AMP caused little if any change in quantity or pattern of gangliosides. The large majority of cells stained in a manner characteristic of astrocytes: positive for glial fibrillary acidic protein, negative for galactosyl ceramides. Staining with cholera toxin and anti-GM1 antibody was essentially negative, as was that with tetanus toxin, A2B5 monoclonal antibody, and antibody to GD3. All evidence thus points to cultured astrocytes of rat and chick brain containing appreciable gangliosides, most of which are GM3 and GD3 with the majority of the remainder comprising structures other than the gangliotetraose type. 相似文献
2.
Oumhani K Canossi A Piancatelli D Di Rocco M Del Beato T Liberatore G Aureli A Benjoaud A El Aouad R Adorno D Casciani CU Ben Jouad AE 《Human immunology》2002,63(2):129-138
To examine the genetic diversity in Morocco, the polymorphism at the HLA-DRB1 locus was investigated in two populations: the Metalsa group consisting of Berbers from north Morocco (who speak the Tarifit language and live in the Nador area), and the Chaouya group who are Arabic-speaking people from west Morocco (Atlantic coast) living in the Settat area. The DRB1 alleles of 197 healthy unrelated individuals were identified by direct DNA sequencing of exon 2 using fluorescently-labeled primers. A total of 28 and 29 alleles at DRB1 locus were identified in the Metalsa and Chaouya groups, respectively. The most frequent alleles in the Metalsa group are DRB1*03011 (20.2%), DRB1*0701 (12.12%), and DRB1*1302 (11.11%). In the Chaouya group, DRB1*0701 (16.33%), DRB1*15011 (12.76%), and DRB1*03011 (11.73%) are most common. Each population exhibits some specific variants and some uncommon alleles. The frequency of the DRB1*03011 allele differs significantly between the two populations (p = 0.0311). The DRB1 frequency distributions in the two groups suggest the effects of balancing selection. The interpopulation analysis highlighted a strong relatedness, based on genetic distances, between the two Moroccan groups and the other north Africans (the Moroccans from El Jadida area, Moroccan Souss Berbers, Algerians, and Tunisians), and to a lesser extent with the Iberians, French, and Ethiopians. 相似文献
3.
Jill M. Body Salim I. Butrus Daniel M. Laby M. Farooq Ashraf Andrew I. Rabinowitz D. M. Parenti 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1995,233(6):374-376
Background: Anterior segment findings in AIDS patients presenting with cytomegalovirus (CMV) retinitis have not been specifically addressed in the American literature. Methods: Our study evaluated 21 AIDS patients with CMV retinitis. Results: Nineteen (90%) of these patients exhibited corneal endothelial deposits concurrent with CMV retinitis. The endothelial deposits were microscopic, opaque, linear flecks arranged in a reticular-like fashion. Of 42 eyes evaluated, 32 (76%) demonstrated active CMV retinitis. Corneal endothelial deposits were noted in 26 (81%) of the 32 eyes with retinitis. These corneal endothelial deposits were absent in the eyes which did not have CMV retinitis. Conclusion: Meticulous examination of the retina of an HIV-positive or AIDS patient who presents with reticularly arranged, linear, flecked corneal endothelial deposits should be performed to ensure that the diagnosis of CMV retinitis can be ruled out. 相似文献
4.
Tisungane Mvalo Hillary M. Topazian Portia Kamthunzi Jane S. Chen Isobel Kambalame Pilirani Mafunga Noel Mumba Msandeni Chiume Khadija Paseli Gerald Tegha Wiza Kumwenda J. Brett Heimlich Graham Ellis Nigel Key Satish Gopal Irving Hoffman Kenneth I. Ataga Kate D. Westmoreland 《Pediatric blood & cancer》2019,66(11)
5.
6.
Asad Ur Rehman Khan Muhammad Ramzan Muhammad Faisal Iqbal Muhammad Hafeez Mohammed M. Fadhali Hamoud H. Somaily Muhammad Javid Muhammad Waqas Mukhtar Muhammad Farooq Saleem 《Materials》2022,15(22)
Zinc sulfide (ZnS) thin films with variable structural, optical, electrical, and thermoelectric properties were obtained by changing the source-to-substrate (SSD) distance in the physical-vapor-thermal-coating (PVTC) system. The films crystallized into a zinc-blende cubic structure with (111) preferred orientation. The films had a wide 3.54 eV optical band gap. High-quality homogenous thin films were obtained at 60 mm SSD. The sheet resistance and resistivity of the films decreased from 1011 to 1010 Ω/Sq. and from 106 to 105 Ω-cm, when SSD was increased from 20 mm to 60 mm, respectively. The phase and band gap were also verified by first principles that were in agreement with the experimental results. Thermoelectric characteristics were studied by using the semi-classical Boltzmann transport theory. The high quality, wide band gap, and reduced electrical resistance make ZnS a suitable candidate for the window layer in solar cells. 相似文献
7.
Gomaa Mostafa-Hedeab Manal Ewaiss Hassan Taher F. Halawa Farooq Ahmed Wani 《Saudi Pharmaceutical Journal》2022,30(9):1293
Chronic liver disease is a worldwide health problem. Carbon tetra hydrochloride is an environmental toxin which is regarded as highly toxic and a potential human carcinogen. It can cause liver damage through the generation of metabolites and production of free radicals. Green tea contains catechins such as Epigallocatechin gallate which has been found to reduce the inflammation, oxidative stress, and fibrosis in experimental animal models. Hence, it represents a good source to prevent or ameliorate several chronic diseases. Silymarin is extracted from milk thistle seeds and has been found to be an effective agent to reduce the oxidative stress and free radical production and thereby exert protective effects in chronic liver conditions. The present study was planned to keep in view the above-mentioned facts. We included thirty rats in our study and divided them into five groups, each having six rats and the study continued for 8 weeks. Group I received normal saline; Group 2 received i.p. CCl4 injections; Group 3 received CCl4 i.p. injection and Epigallocatechin gallate (EGCG) oral gavage, Group 4 received CCl4 i.p. injection and silymarin by oral gavage; and Group 5 received CCl4 i.p. injection and combined EGCG + silymarin by oral gavage. The study found that in group 2, CCl4 induced significant elevation of ALT and MDA and reduced GSH thereby signifying increased oxidative stress. CCl4 also significantly increased inflammatory (TNFα, NFκB, IL1β, and TGFβ) as well as fibrotic markers (p-ERK and p-Smad1/2 protein expression). EGCG and silymarin significantly reversed the previously mentioned parameters either alone or in combination; however, the effect was more pronounced in case of EGCG. We conclude that EGCG and silymarin possess liver protective effects through their antioxidant, anti-inflammatory, and antifibrotic action. 相似文献
8.
Farooq Anwar Ali Abbas Tahir Mehmood Anwarul‐Hassan Gilani Najeeb‐ur Rehman 《Phytotherapy research : PTR》2019,33(10):2548-2570
The genus Mentha comprises several aromatic species, which are cultivated world‐over due to their distinct aroma and commercial value. In addition to traditional food flavoring uses, Mentha are well recognized for their folk medicinal uses, especially to treat cold, fever, and digestive and cardiovascular disorders. A number of biological activities such as antioxidant, antimicrobial, biopesticidal, antitumor, anticancer, antiviral, antiallergic, antiinflammatory, antihypertensive, and urease inhibitory activity have been ascribed to Mentha. The traditional pharmacological attributes of Mentha herbs can be linked to the occurrence of bioactive phytochemicals such as terpenoids, alcohols, rosmarinic acid, and antioxidant phenolics among others. A rich source of bioactives, different species of Mentha, can be explored as a promising candidate for the development of nutra‐pharmaceuticals. This review covers the nutritional, phytochemical, and traditional medicinal aspects and multiple biological activities of some commonly available species of Mentha so as to explore their potential applications for nutra‐pharmaceutical and cosmo‐nutraceutical industry. Detailed chemical profile and pharmaceutical attributes of various Mentha essential oils are also covered. Moreover, based on computational analysis, quantitative chemical component–antioxidant activity relationship model is reviewed to predict and correlate structure–activity relationship of potential bioactives in selected Mentha essential oils leading to discovery and developmenmt of novel natural drugs. 相似文献
9.
Sameen Ahmed Ayesha Vajeeha Muhammad Idrees Abrar Hussain Rakhtasha Munir Gulshan Zaidi Khadija Zahid Rizwan Ahmed Zareen Fatima Shazia Rafique Niaz M. Achakzai 《Medicine》2023,102(2)
High-risk-human papillomavirus (HR-HPV)-induced cervical cancer is the second most common cause of death among females worldwide. HPV16 is the most prevalent HR-HPV infection worldwide. This study found the genotypic distribution of HR-HPV in the local population and investigated the sequence variations among the E6 and E7 oncogenes of the local HPV16 genotype to the E6 and E7 oncogenes of the foreign HPV16 genotypes and constructed a phylogenetic relationship based on nucleotide sequence comparison among the variants identified in our study along with previously reported isolates that were obtained from different regions of the world. The samples were collected from patients with cervical cancer. Genomic DNA was extracted, and HR-HPV genotypes were determined using real-time PCR. The HPV16 E6 and E7 genes were amplified and sequenced. A HPV16 phylogenetic tree was constructed using the maximum likelihood method with MEGA 7. HPV16 was the most prevalent human papillomavirus (HPV) type identified in the present study. HPV16 isolates belonged to the A1 sublineage of the European branch. Twenty-one nucleotide sequences were included in this analysis. The first, second, and third codon positions are also included. The final dataset included 776 positions. 相似文献
10.
Farooq Ahmed Najma Iqbal Malik Nudra Malik Madeeha Gohar Qureshi Muhammad Shahzad Muhammad Shahid Sidra Zia Kun Tang 《Nutrients》2022,14(13)
Severe Acute Malnutrition (SAM) is a serious public health problem in many low- and middle-income countries (LMICs). Therapeutic programs are often considered the most effective solution to this problem. However, multiple social and structural factors challenge the social inclusion, sustainability, and effectiveness of such programs. In this article, we aim to explore how poor and remote households face structural inequities and social exclusion in accessing nutrition-specific programs in Pakistan. The study specifically highlights significant reasons for the low coverage of the Community Management of Acute Malnutrition (CMAM) program in one of the most marginalized districts of south Punjab. Qualitative data are collected using in-depth interviews and FGDs with mothers and health and nutrition officials. The study reveals that mothers’ access to the program is restricted by multiple structural, logistical, social, and behavioral causes. At the district level, certain populations are served, while illiterate, and poor mothers with lower cultural capital from rural and remote areas are neglected. The lack of funding for nutrition causes the deprioritization of nutrition by the health bureaucracy. The subsequent work burden on Lady Health Workers (LHWs) and the lack of proper training of field staff impact the screening of SAM cases. Moreover, medical corruption in the distribution of therapeutic food, long distances, traveling or staying difficulties, the lack of social capital, and the stigmatization of mothers are other prominent difficulties. The study concludes that nutrition governance in Pakistan must address these critical challenges so that optimal therapeutic coverage can be achieved. 相似文献