Effect of polymeric stabilizers on the size and stability of PLGA paclitaxel nanoparticles.

The aim of this study is to formulate polymeric paclitaxel nanoparticles with various stabilizers to improve solubility, enhance stability, maximize therapeutic efficacy and minimize detrimental toxicities of paclitaxel. In this study, trastuzumab-guided poly lactic-co-glycolic acid (PLGA)-loaded paclitaxel nanoparticles were formulated with pluronic F-127, polyvinyl alcohol (PVA), poloxamer 407, Tween-80, span 20, sodium dodecyl sulfate (SDS), and sodium lauryl sulfate (SLS) at different concentrations (0.5, 1, 1.5 and 2%) using the solvent evaporation method. The nanoparticles were evaluated for physicochemical characteristics and short and long-term stability. The optimum particle size (190 nm ± 12.42 to 350 nm ± 11.1), PDI (0.13 ± 0.02 to 0.2 ± 0.01), surface charge (-19.1mv ± 1.5 to -40.4mv ± 1.6), drug loading (2.43 to 9.5 %) and encapsulation efficiency (greater than 80 %) were obtained with these stabilizers while keeping the polymer concentration, temperature, probe size, amplitude and sonication time constant. The nanoformulations were stably stored at 4 °C. The nanoformulations of paclitaxel with pluronic F-127, polyvinyl alcohol (PVA), and poloxamer 407 were found to be more soluble, stable, uniform in physicochemical properties, and efficient in drug loading and encapsulation for improved therapeutic effects.

Expectations, Fears and Perceptions of doctors during Covid-19 Pandemic.

OBJECTIVES: The aim of this study was to explore the expectations and fears faced by doctors during Covid-19 Pandemic. METHODS: This is a mixed method exploratory survey. A questionnaire exploring expectations of doctors from administration and seniors as well as their fears while working during pandemic, was developed on Google survey Forms. It included eight closed ended questions and four open ended questions. Data was collected through online Google survey Forms during month of March and April 2020. Doctors were approached through email and WhatsApp group. RESULTS: The mean age of participants was 33.58±4.21 years. Female 150(67.5%) and Male 72(32.4%) participated. 29(13.1%) Associate Professor, 34(15.3%) Assistant Professor, 56(25.2%) Senior Residents and 103(46.3%) residents, medical officers and house officers responded to the survey. 134(60.3%) doctors were working in hospitals which were not dealing with Covid-19. Fear included, infecting family members 177(79.7%), rapid spread of disease 140(63%), complications of disease 134(60.3%), becoming a carrier in 64(28.8%) and 62(27.9%) feared missing the diagnosis. More than 80% expected from seniors and administration, of providing PPE, facilitation, continue chain of supply of essential items, ensuring doctor safety, avoiding exposure of all doctors and keeping reserve workforce, limiting routine checkups, avoid panic and 20% had no expectations. CONCLUSION: It was concluded that doctors had their fears and perceptions regarding pandemic which need to be addressed while policy making. They fear wellbeing of their families and contacting Covid-19, if not provided proper PPE. Our study provides insight of expectations, fears and perceptions of our frontline which invariably gives insight of the views of healthcare workers.

Preconcentration and determination of lead and cadmium levels in blood samples of adolescent workers consuming smokeless tobacco products in Pakistan.

The present study was aimed to evaluate the cadmium (Cd) and lead (Pb) levels in the blood samples of adolescent boys, chewing different smokeless tobacco (SLT) products in Pakistan. For comparative purpose, boys of the same age group (12-15 years), not consumed any SLT products were selected as referents. To determine trace levels of Cd and Pb in blood samples, a preconcentration method, vortex-assisted liquid-liquid microextraction (VLLME) has been developed, prior to analysis by flame atomic absorption spectrometry. The hydrophobic chelates of Cd and Pb with ammonium pyrrolidinedithiocarbamate were extracted into the fine droplets of ionic liquid (IL) 1-butyl-3-methylimidazolium hexafluorophosphate, while nonionic surfactant, Triton X-114 was used as a dispersing medium. The main factors affecting the recoveries of Cd and Pb, such as concentration of APDC, centrifugation time, volume of IL and TX-114, were investigated in detail. It was also observed that adolescent boys who consumed different SLT products have 2- to 3-fold higher levels of Cd and Pb in their blood samples as compared to referent boys (p < 0.001).

Speciation of vanadium in coal mining, industrial, and agricultural soil samples using different extractants and heating systems.

A fast microwave-assisted extraction procedure was developed for the speciation of vanadium (V) species in soil samples collected from the vicinity of the Lakhra coal power plant (situated near a coal mining area) and industrial and agricultural areas. Soil samples were treated with two extracting reagents, (NH4)2HPO4 (0.2-1 M) and Na2CO3 (0.1-0.5 M), and heated by conventional and microwave methods for different time intervals to extract V+5 species. The V+4 and total V were extracted from filtration residue and the same subsamples of soil by treating with the acid mixture of HNO3-HCl-HClO4-H2SO4 (1:1:1:1, v/v/v/v). No significant difference between V+5 contents obtained by conventional heating and microwave-assisted extraction was observed (P = 0.485). The extraction efficiency of 0.6 M (NH4)2HPO4 for V+5 was lower (4-7%) than that obtained by 0.2 M Na2CO3 solution. The levels of V+5 were higher in soil samples collected from the vicinity of the Lakhra coal power plant and industrial areas, compared to those obtained from agricultural soil.

COVID-19 pandemic and financial market volatility: A quantile regression approach.

The study examined the nexus between the COVID-19 pandemic and the market volatility of the global markets. For this purpose, a 30-country sample was used based on the most COVID-19 cases and deaths during the study period, from January 1 to December 12, 2020. We employed panel quantile regression and Panel Estimated Generalized Least Square (Panel-EGLS) frameworks to analyze the influence of COVID-19 on volatility in the whole sample and subsamples of emerging and developed markets. Our results of Panel-EGLS showed that the new cases and deaths positively impact volatility in the naïve and control models. The results from quantile regression also illustrated that new deaths and cases have positively influenced market volatility at the 50th and 75th quantiles. From the subsamples, our results demonstrate almost similar signs and significance for the impact of COVID-19 on market volatility in developed and emerging markets in both the naïve and control models. Both the results illustrate that any increase in COVID-19 positively caused volatility in the whole and subsamples at the mean and upper quantile levels. Our results necessitate coordinated global government actions to stabilize markets, mitigate volatility's impact by proactive policies in future health crises, and underscore a monetary policy for stability.

Biosynthesized Silver Nanoparticles Using Alnus nitida Leaf Extract as a Potential Antioxidant and Anticancer Agent.

Biogenic synthesis of silver nanoparticles (AgNPs) using plant extracts is gaining attention as a substitute to the conventional physical and chemical synthesis methods. This study reports a facile, cost-effective, and ecofriendly synthesis of AgNPs using leaf extract of Alnus nitida (A. nitida) and their antioxidant and antiproliferative activities. The biosynthesized AgNPs were characterized using various analytical techniques including UV-visible spectroscopy, energy-dispersive spectrometry, scanning electron microscopy (SEM), Fourier transform infrared (FTIR), X-ray diffraction (XRD), and dynamic light scattering. The antioxidant and cytotoxic potential of the extract and AgNPs was evaluated using different in vitro models. The UV-vis analysis revealed a surface plasmon resonance peak of 400 nm corresponding to the synthesis of AgNPs. SEM analysis confirmed the formation of heterogeneously dispersed particles of nano size, while the XRD and FTIR spectra confirmed the crystallinity and existence of different functional groups that helped in capping and stability of AgNPs. The antioxidant activity of AgNPs and extract, studied by 1,1-diphenyl 2-picryl hydrazyl (DPPH), fluorescence recovery after photobleaching (FRAP), 2, 2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and H2O2 scavenging assays, showed a dose-dependent effect. The AgNPs at 1000 µg/mL significantly scavenged DPPH, FRAP, ABTS, and H2O2 by 66.45, 74.65, 78.81, and 72.56% with an average IC50 value of 33.31, 18.50, 16.46, and 15.65 µg/mL, respectively. The cytotoxic potential investigated by MTT assay revealed promising antiproliferative effects against different cancer cell lines. The IC50 values of AgNPs on MDA-MB-231, A549, and Hep-G2 cells were 14.88, 3.6, and 5.38 µg/mL, respectively. The results showed that AgNPs were more effective against lung and hepatocellular carcinoma. The selectivity index showed that AgNPs remained highly selective in retarding the growth of A549 and Hep-G2 cells as compared to normal cell lines HPAEpiC and HRPTEpiC. Overall, this study showed that biosynthesized AgNPs were associated with considerable antioxidant and cytotoxic effects. Our work suggests that A. nitida-mediated AgNPs should be evaluated further in order to develop safe and effective formulations for the treatment of different degenerative diseases.

Tamoxifen-Loaded Eudragit Nanoparticles: Quality by Design Approach for Optimization of Nanoparticles as Delivery System.

Nanoparticles have numerous applications as drug carriers in drug delivery. The aim of the study was to produce tamoxifen nanoparticles with a defined size and higher encapsulation for efficient tissue uptake with controlled drug release. The quality by design approach was utilized to produce tamoxifen-loaded Eudragit nanoparticles by identifying the significant process variables using the nanoprecipitation method. The process variables (amount of drug, polymer, and surfactant) were altered to analyze the influence on particle size (PS), % encapsulation efficiency (EE). The results showed that the drug and polymer individually as well as collectively have an impact on PS, while the surfactant has no impact on the PS. The %EE was influenced by the surfactant individually and in interaction with the drug. The linear regression model was endorsed to fit the data showing high R2 values (PS, 0.9146, %EE, 0.9070) and low p values (PS, 0.0004, EE, 0.0005). The PS and EE were confirmed to be 178 nm and 90%, respectively. The nanoparticles were of spherical shape, as confirmed by SEM and TEM. The FTIR confirmed the absence of any incompatibility among the ingredients. The TGA confirmed that the NPs were thermally stable. The in vitro release predicted that the drug release followed Higuchi model.

Evaluation of calcium, magnesium, potassium, and sodium in biological samples (scalp hair, serum, blood, and urine) of Pakistani referents and arthritis patients of different age groups.

BACKGROUND: Rheumatoid Arthritis is a chronic inflammatory disease resulting in joint inflammation (particularly joints of hands, wrists, feet, knees, ankles, and shoulder) that is manifested by swelling and functional impairment. METHODS: This study was designed to compare the levels of calcium (Ca), magnesium (mg), potassium (K), and sodium (Na) in four biological samples (scalp hair, serum, blood, and urine) of patients with rheumatoid arthritis (RA) as compared to referent subjects of both genders who do have not arthritis problems. All patients and referents were divided in two age groups, (46-60) and (61-75) years. A microwave assisted wet acid digestion procedure was used for acid digestion of biological samples. The digests of all biological samples were analysed for Ca, Mg, K, and Na by flame atomic absorption spectrometry (FAAS). The proposed method was validated by using conventional wet digestion of the same sub samples and certified reference samples of hair, serum, blood, and urine. RESULTS: The results indicated significantly lower levels of Ca, Mg, and K in the biological samples (blood, serum, and scalp hair) of male and female rheumatoid arthritis patients when compared to referents of both genders, whereas the levels of Na were found to be high in blood and urine samples of patients as compared to nonrheumatic referents. CONCLUSIONS: These data represent a guide for clinicians and other professionals who will be investigating the deficiency of essential micronutrients in biological samples (scalp hair, serum, and blood) of rheumatoid arthritis patients.

Interaction between selenium and arsenic in biological samples of psoriasis patients.

BACKGROUND: Psoriasis is a noncontagious, chronic skin disease affecting 1 in 50 people worldwide. METHODS: The aim of present study was to compare the levels of arsenic (As) and selenium (Se) in samples of whole blood, urine, and scalp hair of 418 psoriasis patients of both genders aged 25 - 55 years. All psoriatic patients lived in the vicinity of a cement factory, and were categorized as mild, moderate, and severe. For comparison purposes, 395 healthy age-matched referent/control subjects, residents of industrial and non-industrial areas, were selected. The concentrations of essential trace and toxic elements were measured by electrothermal atomic absorption spectroscopy after microwave-assisted acid digestion. The validity and accuracy of methodology was checked by using certified reference materials (CRMs) and the conventional wet acid digestion method on the same CRMs and real samples. RESULTS: The observed mean values of As were significantly higher in scalp hair, blood, and urine samples of patients with mild and severe psoriasis as compared to the controls (p = 0.01 - 0.001), while the concentrations of Se were lower in the scalp hair and blood, but higher in the urine samples of psoriasis patients of all categories. CONCLUSIONS: The deficiency of Se in psoriatic patients may undoubtedly be caused by the toxic element exposures via dust produced by the cement factory.

Tannic acid inhibits lipopolysaccharide-induced cognitive impairment in adult mice by targeting multiple pathological features.

Tannic acid (TA) is a natural compound present abundantly in fruit such as grapes and green tea. In this study, we have evaluated the therapeutic efficacy of TA against Lipopolysaccharide (LPS)-induced oxidative stress-mediated memory impairment, neuroinflammation, insulin signaling impairment, and Amyloid Beta (Aß) deposition in adult male mice. The LPS was administered once per week and TA twice a week to adult male mice for three months consecutively. Behavioral studies were performed using different behavioral models such as balance beam, novel object recognition (NOR), Morris water maze (MWM), and Y-maze tests. The protein expression of different mediators such as TNF-α, p-JNK, pIRS636, BACE1, APP, and Aß was evaluated through western blot and immunofluorescence staining techniques. Biochemical assays were carried out to assess the antioxidant activities of TA. The computational study was conducted to predict the binding mode of TA with target sites of TNF-α. Behavioral studies showed that the TA-treated mice exhibited gradual memory improvement. TA significantly inhibited BACE1 activity and reduced production and accumulation of Aß in the hippocampus of mice brains. Moreover, the TA significantly inhibited LPS-induced ROS production and enhanced the glutathione levels. Furthermore, we have shown via the computational method for the first time that TA inhibits LPS-triggered TNF-á½° and its downstream signaling to reduce AD pathology including memory impairment, neuroinflammation, insulin signaling impairment, and Aß deposition in adult mice. Taken together our current study demonstrates that TA is a potential candidate for the abrogation of LPS-induced neurotoxicity and AD pathology in rodent's models.

Factors and Predictors of Health Related Quality of Life of the General Population of Pakistan.

Background and Objective: The standards of living, improvement in public health, and medical care in Pakistan are increasing day by day, health-related quality of life (HRQoL) has been increasingly acknowledged in various patient's reported outcomes in Pakistan. However, a large-scale general population-based study on assessing HQRoL in Pakistan was not conducted. Therefore, this study aimed to evaluate HRQoL for the general Pakistani population. Material and Methods: A cross-sectional study with a population sample (n = 16,672) was selected from all Pakistan provinces using a stratified sampling approach. The EQ-5D-3L tool was used to measure the HRQoL of the general population of Pakistan. The descriptive and inferential statistics have been done by using SPSS version 20. Results: Overall, 121 health states were reported in this study. EQ-5D index and EQ-VAS scores were 0.74 ± 0.32 and 0.75 ± 0.25, respectively. The percentage of people responding to any problems increased with age. Males have better health as compared to females in all age groups. All demographics were significantly associated (P < 0.01) with the mean EQ5D index and VAS scores except residence (p > 0.05). The regression model reported that age was the best predictor of the EQ-5D index scores after adjusting for the covariates (beta = 0.19; p < 0.001). This study provides Pakistani population HRQoL data measured by the EQ-5D tool, based on a national representative sample. Conclusion: The current study concluded that Age, City, Gender, Education, Occupation, Residence, and House occupancy are significantly affecting HRQOL. The socioeconomically deprived groups and females have inferior health status than more advantaged. The trends detected in high-income nations were usually similar to Pakistan.

Initial experience with a new fenestrated stent graft.

OBJECTIVES: The Anaconda fenestrated stent graft (Vascutek, Inchinnan, United Kingdom) is a new device that can easily be repositioned during deployment. This study evaluated its feasibility for treating abdominal aortic aneurysms with inadequate infrarenal sealing zones. METHODS: Patients undergoing stent graft placement at two institutions in the United Kingdom were recruited. RESULTS: A total of 12 visceral vessels were accommodated with 8 fenestrations for renal arteries and 4 superior mesenteric artery valleys/scallops in 4 patients. One type Ib endoleak was identified at the 1-month follow-up and successfully treated. CONCLUSIONS: The Anaconda fenestrated stent graft device can be used for the repair of abdominal aortic aneurysms with hostile anatomy and has acceptable immediate and short-term results.

Effects of selenium supplementation on iodine and thyroid hormone status in a selected population with goitre in Pakistan.

BACKGROUND: Selenium (Se) has an essential role in thyroid hormone metabolism. It has the potential to play a major part in the outcome of iodine (I) deficiency The aim of the present study was to evaluate the Se and I status of biological samples (serum and urine) of 160 goitrous male (GMPs) and 195 female patients (GFPs). The supplemental effects of Se (200 microg/day) and I (100 - 125 microg/day) were evaluated after 6 months. For comparison purposes, non-goitrous subjects of both genders (n = 440) with same age group and socioeconomic status were also selected. METHODS: Hydride generation atomic absorption spectrometry (HGAAS) was used to investigate the Se concentration in the biological samples, prior to microwave assisted acid digestion. Quality control for the methodology was established by comparing the results obtained with certified samples with those obtained by conventional wet acid digestion method on the same CRMs and real samples. RESULTS: The mean serum Se concentration was significantly lower, while urinary Se was higher in GMPs and GFPs as compared to control subjects (p < 0.005 and < 0.007, respectively). The levels of I, free tri-iodothyronine, and thyroxin were found in goitrous patients of both genders were low compared to age matched healthy controls (p < 0.015, < 0.006, and < 0.002, respectively). On the other hand, high levels of thyroid stimulating hormone were observed in GMPs and GFPs (p < 0.009). CONCLUSIONS: It was observed that Se in biological samples of hypothyroid patients can play an important role in determining the severity of the hypothyroidism associated with iodine deficiency. A wide-scale epidemiological study is recommended together with the examination of the potential preventive role of Se supplementation in endemic goiter regions.

Evaluation of status of calcium, magnesium, potassium, and sodium levels in biological samples in children of different age groups with normal vision and night blindness.

BACKGROUND: The most common cause of blindness in developing countries is vitamin A deficiency. The World Health Organization (WHO) estimates 13.8 million children have some degree of visual loss related to vitamin A deficiency. The causes of night blindness in children are multifactorial and particular consideration has been given to childhood nutritional deficiency, which is the most common problem found in underdeveloped countries. Such deficiency can result in physiological and pathological processes that in turn influence biological sample composition. Vitamin and mineral deficiency prevents more than two billion people from achieving their full intellectual and physical potential. METHODS: This study was designed to compare the levels of magnesium (Mg), calcium (Ca), potassium (K), and sodium (Na) in scalp hair, serum, blood, and urine of night blindness children in two age groups, (1-5) and (6-10) years, of both genders comparing them to sex- and age-matched controls. A microwave assisted wet acid digestion procedure was developed as a sample pretreatment for the determination of Mg, Ca, K, and Na in biological samples of children with night blindness. The proposed method was validated by using conventional wet digestion and certified reference samples of hair, serum, blood, and urine. The digests of all biological samples were analysed for Mg, Ca, K, and Na by flame atomic absorption spectrometry (FAAS) using an air/acetylene flame. RESULTS: The results indicated significantly lower levels of Mg, Ca, and K in the biological samples (blood, serum, and scalp hair) of male and female children with night blindness and higher values of Na compared with control subjects of both genders. CONCLUSIONS: These data present guidance to clinicians and other professionals investigating deficiency of essential mineral elements in biological samples (scalp hair, serum, and blood) of children with night blindness.

Evaluation of calcium, magnesium, potassium, and sodium in biological samples of Pakistani viral hepatitis (A-E) patients and controls.

BACKGROUND: The aim of the present study was to compare the level of calcium (Ca), magnesium (Mg), potassium (K), and sodium (Na) in biological samples (serum, blood, urine, and scalp hair) of patients suffering from different types of viral hepatitis (A, B, C, D, and E; n = 521) of both genders, ages ranged between 31-45 years. For comparative study, 255 age-matched subjects of both genders, residing in the same city, were selected as controls. METHOD: The elements in the biological samples were analyzed by flame atomic absorption spectrophotometry prior to microwave-assisted acid digestion. The validity and accuracy of the methodology was checked by using certified reference materials (CRMs) and values obtained by conventional wet acid digestion method on the same CRMs. RESULT: The results of this study showed that the mean value of Na was higher in blood, sera, and scalp hair samples of hepatitis patients, while Ca, Mg and K levels were found to be lower than age-matched control subjects. The urinary levels of these elements were found to be higher in the hepatitis patients than in the age-matched healthy controls (p < 0.05). CONCLUSIONS: These results are consistent with data reported in literature, confirming that the deficiency of essential mineral elements and sodium overload can directly cause lipid peroxidation and eventually hepatic damage.

Evaluation of zinc, copper and iron in biological samples (scalp hair, blood and urine) of tuberculosis and diarrhea male human immunodeficiency virus patients.

BACKGROUND: The consequence of a deficiency in trace elements has been associated with an increased risk of human immunodeficiency virus type 1 (HIV-1) disease progression and mortality. This study examined the association between low scalp hair and blood zinc, copper, and iron concentrations and opportunistic infections in hospitalized patients with the acquired immune deficiency syndrome (AIDS). METHODS: The study was performed on sixty two male HIV+ patients (HIV-1) from different cities in Pakistan. The patients were divided in two groups according to secondary infections (tuberculosis, diarrhea and high fever). The biological samples (scalp hair, blood, and urine) were collected from AIDS patients. For comparative study, 120 healthy subjects (males) of the same age group (31 - 45 years), socio-economic status, localities, and dietary habits were also included. The elements in the biological samples were analyzed by flame atomic absorption spectrophotometry prior to microwave-assisted acid digestion. The validity and accuracy of the methodology was checked using certified reference materials (CRMs) and values obtained by conventional wet acid digestion method of the same CRMs. RESULTS: The results indicated significantly lower levels of Fe and Zn and high levels of Cu in the biological samples (blood and scalp hair) of male HIV-1 patients compared with control subjects. It was observed that the low levels of zinc and iron may be predictors for secondary infections in HIV-1 patients. There was a significant decrease in mean values of Fe and Zn in whole blood and scalp hair samples of three groups of AIDS patients as compared to a control healthy male group (p < 0.001). CONCLUSIONS: Deficiency of Zn and Fe might play a role in the development of AIDS in the subjects of this study.

Evaluation of zinc in scalp hair and blood samples of tuberculosis and diarrhea male human immunodeficiency virus patients.

BACKGROUND: The consequence of zinc (Zn) deficiency has been associated with an increased risk of human immunodeficiency virus type 1 (HIV-1) disease progression and mortality. METHODS: This study examined the association between low scalp hair and blood Zn concentrations and opportunistic infections in hospitalized patients with the acquired immune deficiency syndrome (AIDS). The study was performed on sixty two male HIV+ patients (HIV-1) from different cities in Pakistan. The patients were divided in two groups according to secondary infections (tuberculosis, diarrhea, and high fever). The biological samples (scalp hair and blood) were collected from AIDS patients, and for comparative study, 120 healthy subjects (males) of same age group (31 - 45 years), socio-economic status, localities, and dietary habits were also included. RESULTS: The Zn in biological samples was determined by flame atomic absorption spectrometry prior to microwave assisted acid digestion. The proposed method was validated by a certified sample of human hair BCR 397 and Clincheck control-lyophilized human whole blood. It was observed that the low levels of Zn may be predictors for secondary infections in HIV-1 patients. There was a significant decrease in mean values of Zn in whole blood and scalp hair samples in both groups of AIDS patients as compared to a controlled healthy male group (p < 0.001). CONCLUSIONS: Deficiency of zinc might play a role in the development of AIDS in the subjects of this study.

Evaluation of arsenic, cadmium, lead, nickel, and zinc in biological samples (scalp hair, blood, and urine) of tuberculosis and diarrhea male human immunodeficiency virus patients.

BACKGROUND: The consequence of a deficiency in trace elements has been associated with an increased risk of human immunodeficiency virus type 1 (HIV-1) disease progression and mortality. This study examined the association between high scalp hair and blood arsenic, cadmium, lead, and nickel concentrations and opportunistic infections in hospitalized patients with the acquired immune deficiency syndrome (AIDS). METHODS: The study was performed on sixty two male HIV+ patients (HIV-1) from different cities of Pakistan. The patients were divided in two groups according to secondary infections (tuberculosis, diarrhea, and high fever). The biological samples (scalp hair, blood, and urine) were collected from AIDS patients, and for comparative study 120 healthy subjects (males) of same age group (31 - 45 years), socio-economic status, localities, and dietary habits were also included. The elements in the biological samples were analyzed by electrothermal atomic absorption spectrophotometry, prior to microwave-assisted acid digestion. The validity and accuracy of the methodology was checked using certified reference materials (CRMs) and with values obtained by conventional wet acid digestion method on same CRMs. RESULTS: The results indicated significantly higher levels of As, Cd, Ni, and Pb in the biological samples (scalp hair, blood, and urine) of male HIV-1 patients, compared with control subjects. It was observed that the high levels of these toxic elements may be predictors for secondary infections in HIV-1 patients. There was a significant increase in mean values of As, Cd, Ni, and Pb in whole blood, scalp hair, and urine samples of three groups of AIDS patients as compared to a controlled healthy male group (p < 0.001). CONCLUSIONS: These data present guidance to clinicians and other professionals investigating toxicity of As, Cd, Ni, and Pb in biological samples of AIDS patients.

The influence of environmental exposure on lead concentrations in scalp hair of children in Pakistan.

In the present study the environmental and occupational exposure of Pb has been assessed by analyzing the scalp hair (SH) of children (both genders), residing in the vicinity of industrial area of Hyderabad, Pakistan. A total of 339 children attending primary schools situated in the industrial area, age ranged 5-10 years, while for comparative purpose children of the same age group from schools located in an area devoid of industries, were selected. The scalp hair was oxidized by acid mixture in a microwave oven prior to determination of Pb by graphite furnace atomic absorption spectrometry. The concentration profile of Pb in SH of children showed that the level changed significantly (44-64%) with changes of living habits or environmental exposure. The influence of age, sex, and family occupation on the children's hair Pb concentration was also evaluated. Significant differences in SH-Pb levels were observed between the exposed (EXC) and non-exposed (NEC) children (p<0.01). The concentration of Pb in boys of exposed (EX) and non-exposed (NEX) area was more than in girls of the corresponding localities. The boys and girls of NEX and EX areas have SH-Pb in the range of 3.97-5.4 and 6.06-13.7 µg g(-1) and 3.41-7.4 and 5.56-11.5 µg g(-1), respectively. The Pb levels increased with age in both study groups.

Development of extraction methods for speciation analysis of selenium in aqueous extracts of medicinal plants.

Advanced extraction methods have been developed for direct speciation of dissolved inorganic and organic selenium (Se) species in aqueous extracts of medicinal plants (MPs). The inorganic species of Se (SeIV and SeVI) were separated from organic forms by adsorbing inorganic Se on alumina, while the organic Se was not retained. The retained inorganic Se species was eluted with 10 mL 0.2 M HCl. The total inorganic Se species was determined after prereduction of SeVI into SeIV with concentrated HCl. The SeIV in the eluent and total inorganic Se species were then complexed with diethyldithiocarbamate. The resultant complexes were entrapped in the nonionic surfactant Triton X-114. The total Se, organic Se, total inorganic Se, and SeIV species were determined by electrothermal atomic absorption spectrometry with a modifier. The SeVI concentration was obtained by subtracting SeIV from total inorganic Se contents. The main factors affecting the methodologies were investigated in detail. Under the optimized experimental conditions, the LOD for SeIV was 50 microg/L. Among dissolved inorganic and organic Se species in aqueous extracts of MPs, organic Se species were present in the range of 74-84%, SeIV 3.62-7.47%, and SeVI 12.4-18.57% of total Se contents.