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1.
Colloids Surf B Biointerfaces ; 75(2): 490-5, 2010 Feb 01.
Article in English | MEDLINE | ID: mdl-19833487

ABSTRACT

Gum kondagogu (Cochlospermum gossypium), a naturally occurring tree biopolymer, is exploited as a biosorbent to remove metal ions from aqueous solutions. The removal efficiency of toxic metals by gum kondagogu was determined quantitatively in the order Cd2+ > Cu2+ > Fe2+ > Se2+ > Pb2+ > total Cr > Ni2+ > Zn2+ > Co2+ > As2+ at pH 5.0+/-0.1 and temperature 25+/-2 degrees C by inductively coupled plasma-mass spectrometry (ICP-MS). The biosorption (%) of various metal ions tested was found to be in the range of 97.3-16.7%, at pH 5.0. The morphological and mechanisms of interaction of toxic metal ions with gum kondagogu were assessed by scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM-EDXA) and X-ray diffraction (XRD) spectrum. The analysis indicated that biosorption process included morphological changes, precipitation, complexation and ion exchange mechanism for the removal of metal ions by the gum. XRD analysis indicated the amorphous nature of gum kondagogu, which facilitate metal biosorption. The metal ions adsorption leads to its deposition on the gum kondagogu matrix in a crystalline state.


Subject(s)
Bixaceae/chemistry , Colloids/chemistry , Metals, Heavy/isolation & purification , Metals, Heavy/toxicity , Plant Gums/chemistry , Water Pollutants, Chemical/isolation & purification , Water Pollutants, Chemical/toxicity , Adsorption/drug effects , Biodegradation, Environmental/drug effects , Microscopy, Electron, Scanning , Spectrometry, X-Ray Emission , Spectrophotometry, Atomic , X-Ray Diffraction
2.
Biol Trace Elem Res ; 131(3): 255-62, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19352596

ABSTRACT

Element contents of teeth elucidate exposure nature, but less is known about association of tooth element concentrations of diabetics and hypertensives with exposure profile. Present study aims to estimate copper, chromium, iron, zinc, nickel, and lead concentrations in the permanent teeth of control, diabetic, and hypertensive subjects from Mysore. The results show that lead levels of teeth (Pb-T) are higher in the hypertensives and diabetics, whereas copper levels of teeth (Cu-T) are lower in the hypertensives and users of stainless steel utensils than that of controls and users of mixed utensils. The elevated Cu-T levels found in the users of mixed utensils that being made of several metals are ascribed to leaching effect of sour and spicy food of Indian cuisine. The element levels were influenced by diet (Zn-T), place of living, sex and income (Pb-T) of the subjects, but not by age, drinking water from different sources, and certain habits viz., smoking, alcohol consumption, chewing betel, and nut. Thus, it is evident that high Pb-T and low Cu-T levels may be related with diabetes and hypertension and high Pb-T and Cu-T levels, respectively, in the urbanites, and the users of mixed utensils may show different exposure profiles from environment and utensils.


Subject(s)
Diabetes Mellitus/metabolism , Hypertension/metabolism , Tooth/chemistry , Trace Elements/analysis , Adult , Aged , Aged, 80 and over , Case-Control Studies , Cooking and Eating Utensils , Copper/analysis , Copper/toxicity , Environmental Exposure , Female , Humans , India , Lead/analysis , Lead/toxicity , Male , Middle Aged , Trace Elements/toxicity
3.
Sci Total Environ ; 372(2-3): 474-9, 2007 Jan 01.
Article in English | MEDLINE | ID: mdl-17140638

ABSTRACT

Specific elements are bioconcentrated in human hair and nails, which have unique advantages of application in population monitoring studies thereby, recognized as biological tools for disease diagnosis and prevention. However, investigations are meager for relative element profile in hair and nails of same subjects. In this study, hair and nails were analyzed to find effects of age, sex, smoking habit, diet, urban and rural exposure gradients, occupation, and health on element levels. Scalp hair and fingernails were sampled along with a questionnaire from urban and rural subjects of New Delhi; patients of hypertension, coronary heart disease, and diabetes were identified clinically. Cadmium, chromium, copper, nickel, lead and zinc concentrations were determined by AAS in both the samples; CRM (human hair powder) analysis showed acceptable precision and accuracy in element measurement. In comparison to controls, Cr-H and Zn-H levels were lower respectively in female hypertensive and total hypertensive subjects, whereas, Zn-N and Cu-N were lower respectively in total CHD and diabetic subjects, and hypertensive and CHD urban subjects. Cd concentrations were higher in both the samples of tobacco smoking rural subjects than that of non-smokers. Farmers had lower Pb-H than rural businessmen did. Cr, Cu, Ni, and Zn concentrations were different due to rural and urban gradient but not to the influence of age, sex, and diet. Pb value was alone correlated between the paired samples. Thus, higher Cd levels in the smokers and lower Cr, Cu and Zn levels in the patients were observed.


Subject(s)
Coronary Disease/metabolism , Diabetes Mellitus/metabolism , Hair/chemistry , Hypertension/metabolism , Metals/analysis , Nails/chemistry , Adolescent , Adult , Aged , Case-Control Studies , Environmental Monitoring/methods , Female , Humans , Male , Middle Aged , Rural Population , Scalp , Urban Population
4.
Int J Epidemiol ; 35(6): 1522-9, 2006 Dec.
Article in English | MEDLINE | ID: mdl-16997852

ABSTRACT

INTRODUCTION: India is undergoing rapid epidemiological transition as a consequence of economic and social change. The pattern of mortality is a key indicator of the consequent health effects but up-to-date, precise, and reliable statistics are few, particularly in rural areas. METHODS: Deaths occurring in 45 villages (population 180 162) were documented during a 12-month period in 2003-04 by multipurpose primary healthcare workers trained in the use of a verbal autopsy tool. Algorithms were used to define causes of death according to a limited list derived from the international classification of disease version 10. Causes were assigned by two independent physicians with disagreements resolved by a third. RESULTS: A total of 1354 deaths were recorded with verbal autopsies completed for 98%. A specific underlying cause of death was assigned for 82% of all verbal autopsies done. The crude death rate was 7.5/1000 (95% confidence interval, 7.1-7.9). Diseases of the circulatory system were the leading causes of mortality (32%), with similar proportions of deaths attributable to ischaemic heart disease and stroke. Second was injury and external causes of mortality (13%) with one-third of these deaths attributable to deliberate self harm. Third were infectious and parasitic diseases (12%). Tuberculosis and intestinal conditions each caused one-third of deaths within this category. HIV was assigned as the cause for 2% of all deaths. The fourth and fifth leading causes of death were neoplasms (7%) and diseases of the respiratory system (5%). CONCLUSION: Non-communicable and chronic diseases are the leading causes of death in this part of rural India. The observed pattern of death is unlikely to be unique to these villages and provides new insight into the rapid progression of epidemiological transition in rural India.


Subject(s)
Chronic Disease/mortality , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Autopsy , Cardiovascular Diseases/mortality , Cause of Death , Child , Child, Preschool , Communicable Diseases/mortality , Female , HIV Infections/mortality , Humans , India/epidemiology , Infant , Intestinal Diseases/mortality , Male , Middle Aged , Myocardial Ischemia/mortality , Neoplasms/mortality , Parasitic Diseases/mortality , Population Surveillance/methods , Respiratory Tract Diseases/mortality , Rural Health , Self-Injurious Behavior/mortality , Sex Distribution , Stroke/mortality , Tuberculosis/mortality , Wounds and Injuries/mortality
5.
J Phys Condens Matter ; 18(17): 4427-42, 2006 May 03.
Article in English | MEDLINE | ID: mdl-21690793

ABSTRACT

In this paper, we examine the possible influence of extrinsic factors on the electrical and magnetotransport of La(0.67)Ca(0.33)Mn(1-x)Ru(x)O(3) (x≤0.10). Ru substitution results in double metal-insulator transitions (MITs) at T(MI1) and T(MI2), both exhibiting magnetoresistance (MR). No additional magnetic signal corresponding to a second low-temperature maximum (LTM) at T(MI2) could be observed, either in ac susceptibility (χ(')) or in specific heat (C(p)). Typical grain sizes of ∼18 000-20 000 nm, as estimated from the scanning electron microscope (SEM) micrographs, are not so small as to warrant an LTM. The absence of additional peaks in the high statistics powder x-ray diffraction (XRD), a linear systematic increase of the unit cell parameters, close matching of the transition temperatures in resistivity, χ(') and C(p) and their linear systematic decrease with x, and an homogeneous distribution of Mn, Ru and O at arbitrarily selected regions within and across the grains exclude chemical inhomogeneity in the samples. The insensitivity of grain boundary MR at 5 K to Ru composition indicates that the grain boundary is not altered to result in an LTM. Oxygen stoichiometry of all the compounds is close to the nominal value of 3. These results not only exclude the extrinsic factors, but also establish that double MITs, both exhibiting MR, are intrinsic to Ru substituted La(0.67)Ca(0.33)MnO(3).

6.
Rev Environ Contam Toxicol ; 175: 47-78, 2002.
Article in English | MEDLINE | ID: mdl-12206054

ABSTRACT

Hair, as a biological tissue, is unique in that it remains isolated from human metabolic activities and indicates concentration profiles of elements in an individual at a particular time period. However, hair concentrations of elements are affected by different factors that are also specific to certain regions and subjects. Many causal factors have been reported for element level changes in hair; however, in the future more new factors are likely to be reported. All the factors causing change in the hair levels of elements are grouped under four main categories: biological factors, personal factors, environmental factors, and analytical and methodological factors. Comparison of results of element levels in hair for certain factors shows different (positive, negative, or specific) trends because of regional variation. Regarding certain factors (age, sex, health, occupation, etc.), the influence causing the change in element levels is obvious, whereas the influence of other factors (structure of hair, height and weight of the subject, etc.) is obscure. It is very important to consider all the factors at the time of investigation for effective interpretation, validity, and application of results of hair analysis.


Subject(s)
Hair/chemistry , Trace Elements/analysis , Demography , Environmental Exposure , Hair/anatomy & histology , Hair/growth & development , Hair Preparations , Humans
7.
Biol Trace Elem Res ; 77(2): 139-47, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11101046

ABSTRACT

The levels of seven elements determined in the hair were compared between male controls and industrial workers from Madras (South India). Particularly, the concentrations of Cd, Cr, Cu, Mn, and Ni in the foundry workers and Cu, Mn, and Ni in the workers of a workshop and match factory were observed to be higher than that of controls working in the office. In addition, the occupation, age, and period of service of workers had an influence, but diet, smoking habits, income of family, and hair color had no influence on the element levels in the hair.


Subject(s)
Hair/chemistry , Occupational Exposure , Trace Elements/analysis , Adolescent , Adult , Aging/metabolism , Humans , Male , Middle Aged
9.
Biol Trace Elem Res ; 34(1): 89-97, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1382525

ABSTRACT

The concentrations of Cd, Cr, Cu, Mn, Ni, Pb, and Zn were estimated in hair and nails of urban residents of New Delhi. Particularly, hair levels of Cu and Mn in hypertensive males, Cr and Zn in hypertensive females, and Zn in CHD and diabetic females, and nail levels of Zn in CHD and hypertensive females were significantly lower than controls. Thus, it is observed that there exists some positive correlation between element levels in hair and nails and CHD, hypertension, and diabetes of these subjects.


Subject(s)
Coronary Disease/metabolism , Diabetes Mellitus/metabolism , Hair/chemistry , Hypertension/metabolism , Metals/analysis , Nails/chemistry , Urban Population , Coronary Disease/epidemiology , Diabetes Mellitus/epidemiology , Female , Humans , Hypertension/epidemiology , India/epidemiology , Male
10.
Biol Trace Elem Res ; 34(1): 99-105, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1382526

ABSTRACT

Samples of hair and nails collected from the residents of Wazirpur, a village adjacent to New Delhi, were analyzed for Cd, Cr, Cu, Mn, Ni, Pb, and Zn, and correlated with the residents' rural and urban places of occupations. It was observed that Pb and Cd hair levels of males working in rural areas were lower than in male businessmen and officers working in an urban area of New Delhi, thereby showing the different levels of elements exposure of the rural subjects. Such differences in the hair levels of elements were not observed among female subjects. The tobacco smoking habits of male and female rural subjects using hookah were associated with increased Cd levels in hair and nails.


Subject(s)
Hair/chemistry , Metals/analysis , Nails/chemistry , Occupational Exposure , Rural Population , Smoking/metabolism , Adult , Female , Humans , India , Male , Middle Aged , Urban Population
11.
Sci Total Environ ; 114: 161-8, 1992 Apr.
Article in English | MEDLINE | ID: mdl-1594920

ABSTRACT

The concentrations of Cd, Cr, Cu, Mn, Ni and Pb were analysed by AAS in the hair of male and female, controls and workers from firework cottage industries from Sivakasi, Tamil Nadu. When compared with controls, significantly higher levels of Mn and Cr were found in male healthy workers and unhealthy workers with chronic headaches and dizziness. In the case of female workers, higher Mn and lower Pb levels were found, but the level of any element was not significantly different in the workers with ulcers and asthma. There is a possibility of occupational exposure of both male and female workers to the risk of Cr and Mn pollution.


Subject(s)
Hair/chemistry , Occupational Exposure , Trace Elements/analysis , Body Burden , Cadmium/analysis , Chromium/analysis , Copper/analysis , India , Lead/analysis , Manganese/analysis , Nickel/analysis , Scalp
13.
Br J Surg ; 71(9): 730, 1984 Sep.
Article in English | MEDLINE | ID: mdl-6478171

ABSTRACT

The hydatid thrill is a rare but pathognomic sign of hydatid disease. The physical basis of the thrill was studied in two patients with the disease. The thrill occurs when a mother cyst packed with unruptured daughter cysts is gently percussed. The consistency of the wall of the daughter cyst and the tension of the fluid inside it are responsible for making the cysts vibrate and produce the sensation of a thrill. Free fluid from ruptured daughter cysts dampens the vibrations. It is extremely rare for a mother cyst to have all the daughter cysts in an intact condition.


Subject(s)
Echinococcosis, Hepatic/diagnosis , Percussion , Adult , Female , Humans , Middle Aged , Vibration
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