Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “CAMELS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,513 records · Page 84Linked to original sources
PubMed1983

Investigation by photochemically-induced dynamic nuclear polarization and nuclear Overhauser enhancement 1H-NMR of the interaction between beta-endorphin and phospholipid micelles.

The photochemically-induced dynamic nuclear polarization technique has been used to investigate the access of a photoexcited flavin dye to tyrosyl and histidyl residues in [Met]enkephalin and human and camel beta-endorphins, both alone and in the presence of n-dodecylphosphorylcholine micelles. The results indicate that the mode of binding of Tyr-1, but not of residue 27, is similar in the two endorphins and differs from that of Tyr-1 in [Met]enkephalin. In human beta-endorphin, accessibility and mobility of Tyr-27 are strongly reduced in the presence of lipid at physiological pH, whereas in camel beta-endorphin His-27 becomes immobilized only at high pH. Moreover, nuclear Overhauser enhancement experiments suggest a rigidifying influence of the peptide on the polar head groups of the micelles.

Amino Acid Sequence↗
PubMed1994

An assessment of the relationships among species of Camelidae by satellite DNA comparisons.

Tandem satellite arrays and interspersed repetitive DNA components of the New World camelids guanaco, llama, alpaca, and vicuña and the Old World bactrian camel have been identified and compared. Southern hybridizations, using camel restriction fragments as probes, indicated that satellite DNAs in all camelids examined have been conserved since the last common ancestor about 5-10 MY ago. The hybridization profiles, however, varied from totally identical (MspI-sat) to highly differentiated (PstI-sat and EcoRI-sat) between Old and New World species. Repetitive DNA patterns specific of South American camelids were identified by most of the vicuña and guanaco probes and (a) llama and guanaco have undifferentiable patterns, supporting the view that the former is a domesticated form of the latter; (b) vicuña patterns were species-specific and in agreement with its position in a separate taxonomic unit; (c) the presence in alpaca of BamHI, TaqI and EcoRI patterns that are intermediate between those of the species above, suggested that the origin of the alpaca may be found in a cross-breed between the guanaco and vicuña.

Animals↗
PubMed1985

The blood rheology of man and various animal species.

A comparative study has been made of the blood rheology, and its component factors, in horse, sheep, cattle, goat, camel, pig, dog, rabbit and man. The erythrocyte flexibility of horse red cells is high relative to man, that of pig, dog, camel and rabbit comparable, but less flexible, and sheep, cattle and goat relatively inflexible. The erythrocyte flexibility of horse, sheep, cattle and goats does not vary with the plasma fibrinogen level, as occurs with human and rabbit cells. Washing erythrocytes and then suspending them in isotonic saline makes the erythrocytes of all species relatively inflexible. There is a factor in horse plasma, which is not fibrinogen, that makes horse and human erythrocytes suspended in it very flexible. The blood viscosity of all species is comparable at high shear rates (230 s-1) due to the shape of the cells compensating for their flexibility. The variations of blood viscosity at low shear rates (11.5 s-1) were also found to depend on the erythrocyte flexibility, and only influenced indirectly by the fibrinogen concentration. There is no significant effect of temperature on the erythrocyte flexibility of horse, sheep, cattle, goat and a small number of human subjects. This is reflected in the way the viscosity of these bloods varies with temperature.

Animals↗
PubMed2005

Application of monoclonal antibodies in functional and comparative investigations of heavy-chain immunoglobulins in new world camelids.

Of the three immunoglobulin G (IgG) isotypes described to occur in camelids, IgG2 and IgG3 are distinct in that they do not incorporate light chains. These heavy-chain antibodies (HCAbs) constitute approximately 50% of the IgG in llama serum and as much as 75% of the IgG in camel serum. We have produced isotype-specific mouse monoclonal antibodies (MAbs) in order to investigate the roles of HCAbs in camelid immunity. Seventeen stable hybridomas were cloned, and three MAbs that were specific for epitopes on the gamma chains of llama IgG1, IgG2, or IgG3 were characterized in detail. Affinity chromatography revealed that each MAb bound its isotype in solution in llama serum. The antibodies bound to the corresponding alpaca IgGs, to guanaco IgG1 and IgG2, and to camel IgG1. Interestingly, anti-IgG2 MAbs bound three heavy-chain species in llama serum, confirming the presence of three IgG2 subisotypes. Two IgG2 subisotypes were detected in alpaca and guanaco sera. The MAbs detected llama serum IgGs when they were bound to antigen in enzyme-linked immunosorbent assays and were used to discern among isotypes induced during infection with a parasitic nematode. Diseased animals, infected with Parelaphostrongylus tenuis, did not produce antigen-specific HCAbs; rather, they produced the conventional isotype, IgG1, exclusively. Our data document the utility of these MAbs in functional and physiologic investigations of the immune systems of New World camelids.

Animals↗
PubMed1997

Comparison of recent trends in adolescent and adult cigarette smoking behaviour and brand preferences.

OBJECTIVE: To compare trends in smoking behaviour and use of cigarette brands by adults and adolescents. DESIGN: Data analysed in this paper come from tobacco use surveys of adults and teenagers conducted in 18 communities in the United States, as part of the National Cancer Institute's Community Intervention Trial for Smoking Cessation. Data on adult smoking behaviour were obtained from two cross-sectional telephone surveys, one conducted from January to May 1988 (n = 99348), and the second conducted between August 1993 and January 1994 (n = 79890). Data on adolescent smoking behaviour were obtained from two school-based surveys of ninth-grade students (aged 13-16 years), one conducted in autumn 1990 (n = 7097), and the second conducted in autumn 1992 (n = 7277). OUTCOME MEASURES: Adult cigarette smoking prevalence was estimated as the percentage of adults (18+ years) who were identified either by interview or by proxy as a current smoker. Among adolescents, current smokers were defined as those who reported having smoked on one or more of the 30 days preceding the interview. Cigarette brand use by adults was measured by asking current smokers to report the six digit UPC code on the side of the pack of their current cigarettes. A master list of UPC code numbers was developed so that reported codes could be associated with specific brand names. Among adolescents, cigarette brand use was measured by asking current smokers who reported that they usually buy their own cigarettes: "What brand do you usually buy?" RESULTS: In ninth-grade students, smoking prevalence rates increased between 1990 and 1992 in 13 of the 18 communities. Among adults, smoking rates declined between 1988 and 1993 in 17 out of 18 communities. Within the same communities, cigarette brand use was found to be much more tightly concentrated in adolescent smokers compared with adults, with teenage smokers more likely to report using the most heavily advertised cigarette brands--Marlboro, Newport, and Camel. CONCLUSIONS: Smoking prevalence rates have increased among teenagers, but have dropped among adults in the same communities. Among adolescents who smoke, and buy their own cigarettes, the three most heavily advertised brands--Marlboro, Camel, and Newport--have a substantially higher market concentration than among adult smokers.

Adolescent↗
PubMed1998

Recognition of cigarette brand names and logos by primary schoolchildren in Ankara, Turkey.

OBJECTIVE: To assess the smoking behaviour of primary schoolchildren and their ability to recognise brand names and logos of widely advertised cigarettes, compared with other commercial products intended for children. DESIGN: Cross-sectional survey in classroom settings using a questionnaire designed to measure attitudes towards smoking and the recognition of brand names and logos for 16 food, beverage, cigarette, and toothpaste products. SETTING: Ankara, Turkey. SUBJECTS: 1093 children (54.6% boys, 44.4% girls) aged 7-13 years (mean = 10, SD = 1), from grades 2-5. The student sample was taken from three primary schools--one school in each of three residential districts representing high, middle, and low income populations. MAIN OUTCOME MEASURES: Prevalence of ever-smoking, recognition of brand names and logos. RESULTS: Prevalence of ever-smoking was 11.7% overall (13.9% among boys and 9.1% among girls; p < 0.05). Children aged eight years or less had a higher prevalence of ever-smoking (19.6%) than older children (p < 0.002). Ever-smoking prevalence did not differ significantly across the three school districts. Ever-smoking prevalence was higher among children with at least one parent who smoked (15.3%) than among those whose parents did not (4.8%) (p < 0.001). Brand recognition rates ranged from 58.1% for Chee-tos (a food product) to 95.2% for Samsun (a Turkish cigarette brand). Recognition rates for cigarette brand names and logos were 95.2% and 80.8%, respectively, for Samsun; 84.0% and 90.5%, respectively, for Camel; and 92.1% and 69.5%, respectively, for Marlboro. The Camel logo and the Samsun and Marlboro brand names were the most highly recognised of all product logos and brand names tested. CONCLUSIONS: The high recognition of cigarette brand names and logos is most likely the result of tobacco advertising and promotion. Our results indicate the need to implement comprehensive tobacco control measures in Turkey.

Adolescent↗
PubMed1986

Studies on the association of Aspergillus fumigatus with ocular infections in animals.

The occurrence and aetiological significance of Aspergillus fumigatus, an opportunistic pathogen, have been studied in 93 animals with various ophthalmological problems. A total of 93 eye swabs collected from 35 mules, 26 dogs, 13 fowl, 11 cattle, five buffaloes and three camels were investigated mycologically for the presence of A fumigatus. The pathogen was isolated in pure and heavy growth from the swabs from two dogs, one bull, one mule and one fowl. The fungus was also demonstrated directly in clinical material by the potassium hydroxide technique. A fumigatus could not be cultured from the buffaloes and camels. All the five cases had been treated with broad spectrum antibiotics and cortisone and two had received traumatic injury to the eyes (one mule and a bull). The organism was not isolated in pure culture from the conjunctival swabs of 22 apparently healthy animals (11 dogs, six mules, three fowl and two cattle). Many other saprophytic fungi were recovered in mixed cultures but were considered to be contaminants. The clinical signs and diagnostic criteria of oculomycosis have been discussed.

Animals↗
PubMed2001

Incorporation of long CDR3s into V domains: implications for the structural evolution of the antibody-combining site.

Available data suggest that 'primitive' antibody-combining sites often include longer than average HCDR3s. Long HCDR3 sequences have been reported in diverse vertebrates, including humans, cattle, camels and sharks. These long HCDR3 segments contain unusual sequence features such as stretches of Gly or Pro residues and multiple Cys residues. We examined how longer than average HCDR3s were accommodated in the V domains of human, murine and camel antibodies with known three-dimensional structures. The main conclusions were that (1) HCDR3s longer than 12 residues should protrude outward from the V domains; (2) descending HCDR3 polypeptides may utilize VL (including LCDR3) constituents as a platform, supporting the protruding segments; (3) intra- and inter-HCDR disulfides are frequently formed to rigidify the structure of HCDR3 or the combining site, and (4) V and C domains were possibly more similar in primordial antibodies than they are in their present day counterparts.

Amino Acid Sequence↗
PubMed2002

The immunodiagnostic potential of protoscolex antigens in human cystic echinococcosis and the possible influence of parasite strain.

The results of ELISA, SDS-PAGE and western blotting indicated that the protoscolex antigens of Echinococcus granulosus (of 10-125 kDa) included antigens recognized by sera from human cases of cystic echinococcosis (CE). Some of the latter antigens (of approximately 79, 59, 45, 38, 31 and 29 kDa) exhibited cross-reactivity with sera from humans with other parasitic infections, including alveolar echinococcosis, cysticercosis and African trypanosomiasis. The 31-kDa antigen recognized by IgG antibodies in human CE sera only appeared to be present in the extracts of protoscoleces from sheep, and not in the corresponding extracts from horse or camel cysts. In contrast, the human CE sera recognized a 45-kDa protoscolex antigen only present in the horse cysts and a 125-kDa antigen present in the camel and horse (but not sheep) cysts. Extracts of protoscoleces from different species of hosts might therefore provide a source of strain-specific diagnostic antigens for human CE.

Animals↗
PubMedDate not supplied

Trypanosoma evansi sialidase: surface localization, properties and hydrolysis of ghost red blood cells and brain cells-implications in trypanosomiasis.

A membrane-bound sialidase was isolated from blood stream (BS) Trypanosoma evansi partially purified and characterized. The enzyme is a glycosyl phosphatidyl inositol (GPI) membrane anchored protein. It was solubilized from T. evansi cells recovered from infected camel blood by detergent treatment with Triton CF 54 and partially purified by a series of chromatography steps. The enzyme was optimally active at pH 5.5 and 37 degrees C. It had a KM and Vmax values of 4.8 x 10(-6) M and 3.75 x 10(-6) mol/min x mg protein with Neu5Acalpha2, 3lac as substrate respectively. The KM and Vmax values with fetuin (4-nitrophenyl-oxamic acid) as substrate were 2.9 x 10(-2) M and 4.2 x 10(-3) mol/min x mg protein in the same respect. Kinetic analysis with methly umbelliferyl sialate (MU-Neu5Ac) gave KM and Vmax values of 0.17 mM and 0.84 mmol/min x mg protein respectively. The T. evansi SD could hydrolyse internally linked sialic acid residues of the ganglioside GM2, but was inactive towards colomic acid, and NeuSAc2, 6. lac. When ghost red blood cell (RBC) was used as substrate, it desialylated the RBC in the following order of efficiency; mouse, rat, camel, goat, and dog. Similarly, cerebral cells isolated from BalbC mouse was desialylated by the T. evansi SD. Inhibition studies using 2-deoxy-2, 3 didehydro-N-acetyl neuraminic acid (NeuAc2, 3en) against MU-Neu5Ac revealed a competitive inhibition pattern with Ki of 5.8 microM. The enzyme was also inhibited non-competitively by parahydroxy oxamic acid (pHOA), and competitively by N-ethylmaleimide and N-bromosuccinate with Ki values of 25, 42, and 53 microM, respectively. It was activated by Mg2+ ion and inhibited by Cu2+ and Zn2+.

Animals↗
PubMedDate not supplied

Conserved and non-conserved loci of the glucagon gene in old world ruminating ungulates.

The homology and diversification of genomic sequence encoding glucagon gene among native Egyptian buffalos, camel and sheep were tested using cattle as model. Oligodeoxynucleotide primers designed from the available GenBank data were used for PCR probing of the glucagon gene encoding sequence at different loci. The DNA oligomer probes were constructed to flank either the whole gene encoding sequence or different intra-gene encoding sequences. The PCR products were visualized using agarose gel electrophoresis. All species showed a same size band of prepro-glucagon when PCR was used to amplify the whole gene encoding sequence. In contrary, amplifications of different intra-gene loci failed to give the same results. The results indicated variable degrees of diversity among old world ruminating ungulates in the glucagon gene encoding sequence. Compared with other ruminants, the variation appears predominantly in camel. Surprisingly, the similarity in size between both amplification products of whole gene encoding sequence and the proposed size of glucagon cDNA definitely excludes the possibility of large intervening introns spanning the genomic sequence of the glucagon gene in these species. This indicates that, in contrast to other tested mammals, the glucagon gene includes an essentially full-length copy of glucagon mRNA. The study revealed a possible new aspect of glucagon gene evolution in order to correlate its corresponding protein function among different ruminant species.

Amino Acid Sequence↗
PubMed1988

A study of the genital organs of the female dromedary (Camelus dromedarius).

Camels (416 pregnant, 118 non-involuted post partum and 730 non-pregnant) were examined post mortem. Large follicles (greater than 10 mm), small follicles (5-10 mm) and non-functional ovaries were observed in 144 (20.7%), 127 (18.3%) and 424 (61.0%) respectively out of 695 normal non-pregnant organs. Season did not exert any significant influence on the frequency of these groups. Recently formed and regressing CL after sterile mating were occasionally seen. Corpora albicantia (3-15 mm) were the most frequent structures observed in non-pregnant organs of parous camels as well as in pregnant tracts, together with the CL of pregnancy: 17% of ovaries contained more than one luteal structure. Pregnancy was easily recognized as early as 40-45 days of gestation because of the marked swelling of the left uterine horn in which 99.52% of the pregnancies were located.

Animals↗
PubMed1996

Husbandry and diseases of camelids.

Camels of the Old World and the New World have provided the indigenous human population with meat, milk, fibre and fuel, also serving as beasts of burden to carry loads, for millennia. With the advent of motorized vehicles, the use of camelids became obsolete except in isolated situations. The numbers of camelids diminished dramatically. A reversal of that trend is now occurring, with a recognition that these animals still function in their respective environments better than any other species of livestock. Camelids have always been popular animals in zoos. Camels and two of the South American camelids are domestic animals which adapt well to contained management. They have a unique ability to obtain nourishment from harsh forages. Their reproductive physiology is different from that of any other livestock species.

Animal Husbandry↗
PubMed1980

Gastrointestinal osmolality electrolyte and organic acid composition in five species of East African herbivorous mammals.

inherent differences observed in ionic composition of gastrointestinal contents due to diet, feeding regimen and (or) site along the length of the digestive tract were controlled so that a clearer understanding of species differences could be obtained. Three species of ruminants (i.e., Zebu cattle, sheep and goat), a pseudo-ruminant (camel) and a nonruminant (donkey) were compared. Specific differences were observed in organic acid concentration, pH and electrolyte composition at various sites along the length of the tract. In general, Zebu cattle exhibited major differences in colonic volatile fatty acid, sodium and chloried concentrations when compared to other species. Donkeys, camels, sheep and goates were generally similar in their gastrointestinal ionic composition.

Animals↗
PubMed1983

An active intermediate host role for man in the life cycle of Echinococcus granulosus in Turkana, Kenya.

Hydatid material removed at operation from 97 Turkana was compared for fertility and viability with hydatid material removed from camels, cattle, sheep, and goats. The results showed that the human material was extremely fertile and viable, as was material from the camels, goats, and sheep. Cattle cysts were invariably sterile, and the protoscoleces, when present, were comparatively less viable. The high incidence and fertility of hydatid cysts in the Turkana, together with the lack of burial customs thus allowing dogs to have ready access to infected human corpses, means that the Turkana are potential biological participants in the cyclic transmission of Echinococcus granulosus in this region. This is a unique situation, for elsewhere in the world man is regarded as an accidental host who plays no role in the parasite's life cycle.

Adolescent↗
PubMed1995

Antibodies to hemorrhagic fever viruses in domestic livestock in Niger: Rift Valley fever and Crimean-Congo hemorrhagic fever.

A repository of domestic animal sera collected in Niger between 1984 and 1988 was assayed for antibody against two zoonotic hemorrhagic fever viruses known to be present in the West African Sahel. A total of 2,540 serum samples from 2,324 cattle, sheep, goats, and camels were tested by an IgG-specific enzyme-linked immunosorbent assay (ELISA) and the 80% plaque reduction neutralization test (PRNT80) for Rift Valley fever (RVF) virus antibody. Of the 2,540 sera tested for RVF-specific IgG antibody, 1,676 sera from cattle, sheep, and goats were examined for RVF-specific IgM antibody by ELISA. A subset of 2,263 sera were examined for evidence of Crimean-Congo hemorrhagic fever (CCHF) virus antibody by an IgG-specific ELISA. Antibody against CCHF virus was found to be most prevalent in adult cattle (422 of 732 or 57.7% positive) sampled at nine locations in the Niamey area. The highest prevalence for RVF neutralizing antibodies was found in camels from the Agadez Department with 67 (47.5%) of 141 positive. The results indicate that both CCHF and RVF viruses are circulating in Niger and are potential zoonotic health risks.

Animals↗
PubMed1998

Indication of the presence of two distinct strains of Echinococcus granulosus in Iran by mitochondrial DNA markers.

Sixteen isolates of Echinococcus granulosus, collected from Iranian patients at surgery, and from domestic animals, including sheep, goats, cattle, and camels at slaughterhouses in Tehran and central and southern Iran were analyzed for DNA nucleotide and predicted amino acid sequence variation within regions of the mitochondrial cytochrome c oxidase I (COI) and NADH dehydrogenase subunit I (NDI) genes. A polymerase chain reaction-restriction fragment length polymorphism method, based on the DNA sequence variation in the NDI gene, was also used to rapidly survey the E. granulosus isolates. The isolates were categorized into two distinct and uniform genotype groupings. The analysis clearly indicated that the camel/dog strain (G6 genotype) of E. granulosus as well as the cosmopolitan, common sheep strain (G1 genotype) occur in Iran. The G1 genotype was found present in all four human isolates examined and it was more prevalent in domestic animals than the camel-restricted G6 genotype. In E. granulosus-endemic areas of Iran it is evident, therefore, that the majority of E. granulosus-infected livestock animals can potentially act as reservoirs of human infection, and this has important implications for hydatid control and public health.

Amino Acid Sequence↗
PubMed2002

Cryptosporidiosis among animal handlers and their livestock in Basrah, Iraq.

OBJECTIVE: To investigate the prevalence of cryptosporidiosis among groups at risk (animal handlers) and among domestic animals. DESIGN: Comparative study with zoonotic aspect. METHOD: Stool samples were collected from 60 animal handlers, 175 non-animal handlers and 198 domestic animals (60 cows, 45 sheep, 45 goats, 25 horses and 23 camels). Direct smear method and then formalin-ether sedimentation method were carried out for stool samples to detect intestinal parasites. Faecal smears were prepared from the sediment and stained by the modified Ziehl-Neelsen method for the recovery of red-pink oocysts of Cryptosporidium. RESULTS: Out of the 60 animal handlers, 30 (50%) were found to be positive for intestinal parasites compared to 26 (14.8%) of non-animal handlers (P < 0.01). Cryptosporidium oocysts were found to be excreted by three (5%) animal handlers and two (1.14%) of the non-animal handlers (P > 0.05). Cryptosporidiosis was also diagnosed in 20%, 13.3%, 17.7% and 12% of cattle, sheep, goats and horses respectively. No single positive case was detected among the examined camels. CONCLUSION: Veterinarians, butchers and breeders should be aware of the disease among farm animals in order to avoid great losses and to prevent its transmission to humans.

Adolescent↗