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611.
612.
Very little research has been conducted in the Himalayan and Karakorum Highlands of northern Pakistan on the aspects of biodiversity and conservation. The present research was carried out within the scope of the Pakistan–German Research Project, Culture Area Karakorum which aims to highlight the Problems and Prospects of High-Mountain Research in northern Pakistan. Naltar Valley, IUCN Management Category no. 4, located in the western Karakorums, is a remote area with difficult access. The current venture is two-fold; first, it describes the floral biodiversity of this remote area in northern Pakistan and second, discusses its exploitation by various entities with certain management implications to follow. Collection of species, their preservation and dialogue with the local, rural communities offered information on the plant biodiversity, providing the first extensive list of flora at the primary-valley level including their altitude range, habit and month of occurrence. In total, 153 plant species belonging to 38 families and 113 genera have been recorded after extensive field research in the area. Dominance has been observed for Asteraceae, Polygonaceae, Saxifragaceae and Rosaceae. Twenty-four plant species from Naltar emerged as ethnobotanically important for local medicinal uses and some commercial uses. Indeed, Thymus serpyllum, Gentiana tianshanica, Stellaria graminea, Geranium wallichianum and Capparris spinosa are the most important medicinal plants and their demand has increased, leading to over-exploitation. Cedrus deodara has completely disappeared from Naltar and Willow Salix sp. has almost been eradicated, except in the sub-alpine belts. The diversity of plant species within this remote area is very important for its obvious contribution to a sound mountain ecosystem. Prior to the present venture, not much was known about the floral aspects of this mountainous region of northern Pakistan. Many species are new additions to the plant list in this area. The species are distributed within the altitude range of 1,700–4,000 m and above, and are further explored for their ethnobotanical uses. It is recorded that some species are extensively used by the indigenous communities, some plant collectors from the lowlands and foreigners as well. Extensive grazing, uprooting of plants and soil-slope erosion intensify the environmental problems. A few species are further used for curing diseases through direct usage or marketing in the lowlands. Unfortunately, due to minor local conflicts, the area has been given low priority for its inclusion in the development and conservation programmes going on in other parts of these mountains. On the other hand, hospitable populations have a greater potential for the success of conservation and the wise usage of programmes. Concerted efforts are required to broaden our understanding of the dynamics of floral values as well as local concepts in this remote part of the world, and to check species decline. For sustainable use, in situ and ex situ conservation, controlled harvesting and aforestation may be the solution. Further extensive field conservation/management research is needed. 相似文献
613.
O'Hara R Mumenthaler MS Davies H Cassidy EL Buffum M Namburi S Shakoori R Danielsen CE Tsui P Noda A Kraemer HC Sheikh JI 《Annals of general hospital psychiatry》2002,1(1):1
OBJECTIVES: (a) To determine the quantity and quality of behavioral problems in older hospitalized patients on acute care units; (b) to determine the burden of these behaviors on staff; and (c) to identify predictors of behavioral problems. METHODS: Upon admission, patients performed the Mini-Mental State Exam (MMSE), the Geriatric Depression Scale (GDS), and information was obtained on age, ethnicity, level of education, living arrangement, and psychiatric history. Two days post-admission, a clinical staff member caring for each patient, performed the Neuropsychiatric Inventory-Questionnaire (NPI-Q) to assess patients' behavioral problems and staff distress. PARTICIPANTS AND SETTING : Forty-two patients, over 60 years of age, admitted to medical and surgical units of the Veterans Affairs Hospitals in Palo Alto and San Francisco, participated. RESULTS: Twenty-three of 42 (55%) patients exhibited behavioral problems. Anxiety, depression, irritability, and agitation/aggression were the most frequently observed behaviors. The severity of the behavioral problems was significantly correlated with staff distress. Lower performance on the MMSE at admission was significantly associated with higher NPI-Q ratings. Specifically, of those cases with scores less than or equal to 27 on the MMSE, 66% had behavioral problems during hospitalization, compared to only 31% of those with scores greater than 27. CONCLUSION: Behavioral problems in older hospitalized patients appear to occur frequently, are a significant source of distress to staff, and can result in the need for psychiatric consultation. Assessment of the mental status of older adults at admission to hospital may be valuable in identifying individuals at increased risk for behavioral problems during hospitalization. 相似文献
614.
Parvez S Sayeed I Pandey S Ahmad A Bin-Hafeez B Haque R Ahmad I Raisuddin S 《Biological trace element research》2003,93(1-3):237-248
Effect of the low level of copper exposure on nonenzymatic antioxidants was studied in a freshwater fish Channa punctatus (Bloch.). Fish were exposed to cupric chloride at the concentration of 10 ppb for 4 wk (28 d) in a static culture condition.
Copper significantly (p < 0.001) increased the serum ceruloplasmin level and total iron-binding capacity. A significant (p < 0.05) increase in reduced glutathione level was recorded in all of the tissues. With regard to nonprotein thiols, copper
decreased their level in the liver, but increased it in the gill. The protein-bound thiols remained unaltered except for an
increase in the liver. Metallothionein (MT) induction was observed in liver only. Copper exposure had no significant effect
on the ascorbic acid level and induced no lipid peroxidation over control values. It is suggested that by modulating the ceruloplasmin
level, copper indirectly protects the fish, as it facilitates conversion of pro-oxidant iron to nonoxidant iron. It also induces
an array of antioxidants that may be beneficial to fish in the case of oxidative stress resulting from chemical pollutants. 相似文献
615.
Sheikh AM Chauhan V Tsiouris JA Mehta PD Burguess K Fenko MD Spivack W Vaughan M Malik M 《Biochimie》2003,85(10):1027-1032
Bear serum alpha(2) macroglobulin (alpha(2)M) was purified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and partially characterized by tryptic digestion of alpha(2)M and analysis of the peptides by peptide mass fingerprinting. The molecular weight of bear serum alpha(2)M was 181 kDa, same as for human serum alpha(2)M, on SDS-PAGE. However, the MALDI mass spectrum of the tryptic digested bear serum alpha(2)M showed that it is different from human alpha(2)M or other data bank proteins. Liquid chromatography (LC)/mass spectrometry (MS)/MS of the proteolytic products of bear serum alpha(2)M showed eight peptides that had similarities to human alpha(2)M suggesting that the protein of interest was indeed alpha(2)M of bear. The polyclonal antibody against bear serum alpha(2)M recognized only one protein from the western blot of bear serum proteins. It also recognized human alpha(2)M. The levels of serum alpha(2)M were significantly increased during hibernating state as compared to active state of bears indicating its protective role from the consequences of the metabolic depression during hibernation. 相似文献
616.
The effects of six flavonoids viz., apigenin, genistein, morin, naringin, pelargonidin and quercetin on the susceptibility of low-density lipoprotein (LDL) to oxidative modification were investigated. Flavonoids were added to plasma and incubated for 3 hr at 37 degrees C, and the LDL fraction was separated by ultracentrifugation. Oxidizability of LDL was estimated by measuring conjugated diene (CD), lipid peroxides and thiobarbituric acid-reactive substances (TBARS), after cupric sulfate solution was added. Quercetin and morin significantly (P<0.01 by ANOVA) prolonged the lag time before initiation of oxidation reaction in dose-dependent manner. They also suppressed the formation of lipid peroxides and TBARS more markedly than other flavonoids. The ability to prolong lag time and suppression of lipid peroxides and TBARS formation was in the following order: quercetin >morin >pelargonidin >genistein >naringin >apigenin. LDL exposed to flavonoids reduced oxidizability. These findings suggest that flavonoids may have a role in ameliorating atherosclerosis. 相似文献
617.
BACKGROUND: The occurrence of Loa loa encephalopathy following mass treatment of onchocerciasis with Mectizan(R) has adversely affected onchocerciasis control efforts in central Africa. Persons with very high densities of L. loa microfilaremia are at increased risk of encephalopathy, but little is known about the geographic distribution of these persons within central Africa. RAPLOA, a new technique that correlates the proportion of community members reporting a history of eyeworm with the prevalence of high-intensity L. loa microfilaremia in that community, may be useful for rapid assessment of areas at potential risk of treatment-related L. loa encephalopathy. Validation of RAPLOA is ongoing. The operational and risk-reduction advantages of RAPLOA over the current technique of village-by-village rapid epidemiologic assessment for onchocerciasis (REA) are unknown. METHODS: We developed a decision model to compare four strategies for minimizing sequelae of L. loa encephalopathy following mass treatment with Mectizan(R) in areas co-endemic for onchocerciasis and loiasis: REA; RAPLOA with threshold eyeworm prevalences of 40% and 20% (RAPLOA-40 and RAPLOA-20, respectively); and combined REA/RAPLOA-40. RESULTS: In the model, all four strategies significantly reduced risk of death and neurologic complications from L. loa encephalopathy, but RAPLOA-20 and REA resulted in half as many such cases as did RAPLOA-40 or combined REA/RAPLOA-40. CONCLUSION: RAPLOA is likely to be useful programmatically in reducing risk of L. loa encephalopathy following mass treatment with Mectizan(R). It also may be cost-saving. Before full-scale implementation, additional data are needed on geographic clustering of high-density L. loa microfilaremia and on RAPLOA's reliability and cost. 相似文献
618.
Twum-Danso NA 《Filaria journal》2003,2(Z1):S7
Of the 207 Serious Adverse Events (SAEs) following treatment with Mectizan® (ivermectin, Merck, Sharpe &; Dohme) that were reported from 1989 to 2001 through the passive SAE surveillance system required of all onchocerciasis mass treatment programs, 65 were cases of 'Probable' or 'Possible' Loa loa Encephalopathy temporally Related to treatment with Mectizan® (PLERM).A retrospective analysis of these 65 PLERM cases revealed that 97% were from southern Cameroon, 85% were male and 93% were being treated with ivermectin for the first time. The mean time to onset of symptoms was 1.7 days (95% CI: 1.3, 2.2) but the mean time to receiving medical attention after the onset of symptoms was 2.0 days (95% CI: 1.5, 2.6). Hospitalization was reported in 53 cases with a mean duration of 27.5 days (95% CI: 13.3, 41.6, n = 35). Clinical outcome was reported in 34 cases: 64.7% recovered fully, 11.8% had partial neurologic deficit and 23.5% died. For the 32 cases where quantitative L. loa data were reported, the arithmetic means with 95% confidence intervals were for 1) peripheral blood: pre-treatment – 164,250 mf/ml (79,537, 248,963; n = 4); post-treatment within 1 month – 3926 mf/ml (2,128, 5,725; n = 21) and within 5 to 6 months – 7800 mf/ml (3417, 12,183; n = 7); and for 2) cerebrospinal fluid: 32 mf/ml (7, 37; n = 10) within 1 month post-treatment.Pending further research on practical methods to exclude individuals with high intensity L. loa infection from onchocerciasis mass treatment programs, more emphasis should be placed on surveillance and monitoring to ensure early recognition, referral and management of SAEs, during the first 2 years when majority of the population is presumably naïve to ivermectin. 相似文献
619.
Naz S Giguere CM Kohrman DC Mitchem KL Riazuddin S Morell RJ Ramesh A Srisailpathy S Deshmukh D Riazuddin S Griffith AJ Friedman TB Smith RJ Wilcox ER 《American journal of human genetics》2002,71(3):632-636
We have identified five different homozygous recessive mutations in a novel gene, TMIE (transmembrane inner ear expressed gene), in affected members of consanguineous families segregating severe-to-profound prelingual deafness, consistent with linkage to DFNB6. The mutations include an insertion, a deletion, and three missense mutations, and they indicate that loss of function of TMIE causes hearing loss in humans. TMIE encodes a protein with 156 amino acids and exhibits no significant nucleotide or deduced amino acid sequence similarity to any other gene. 相似文献
620.
Hansen JL Theilade J Haunsø S Sheikh SP 《The Journal of biological chemistry》2004,279(23):24108-24115
The 7-transmembrane or G protein-coupled receptors relay signals from hormones and sensory stimuli to multiple signaling systems at the intracellular face of the plasma membrane including heterotrimeric G proteins, ERK1/2, and arrestins. It is an emerging concept that 7-transmembrane receptors form oligomers; however, it is not well understood which roles oligomerization plays in receptor activation of different signaling systems. To begin to address this question, we used the angiotensin II type 1 (AT(1)) receptor, a key regulator of blood pressure and fluid homeostasis that in specific context has been described to activate ERKs without activating G proteins. By using bioluminescence resonance energy transfer, we demonstrate that AT(1) receptors exist as oligomers in transfected COS-7 cells. AT(1) oligomerization was both constitutive and receptor-specific as neither agonist, antagonist, nor co-expression with three other receptors affected the bioluminescence resonance energy transfer 2 signal. Furthermore, the oligomerization occurs early in biosynthesis before surface expression, because we could control AT(1) receptor export from the endoplasmic reticulum or Golgi by using regulated secretion/aggregation technology (RPD trade mark ). Co-expression studies of wild type AT(1) and AT(1) receptor mutants, defective in either ligand binding or G protein and ERK activation, yielded an interesting result. The mutant receptors specifically exerted a dominant negative effect on Galpha(q) activation, whereas ERK activation was preserved. These data suggest that distinctly active conformations of AT(1) oligomers can couple to each of these signaling systems and imply that oligomerization plays an active role in supporting these distinctly active conformations of AT(1) receptors. 相似文献