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Indications of Potential Toxic/Mutagenic Effects of World Trade Center Dust on Human Lung Cell Cultures

Problem statement: Respiratory complications have been linked with exposure to dust particulates after the tragedy of September 11th, 2001 at the World Trade Center (WTC) site. Approach: The purpose of these experiments was to investigate the extent of cellular damage resulting from WTC dust exposure. Results: This research project was conducted with human lung fibroblast cells exposed to WTC dust. To determine if cell proliferation levels were affected, cultured cells were exposed to WTC dust at various concentrations in simulated physiological stress environments via decreased serum levels. Results indicated that cell proliferation levels decreased as WTC dust concentrations increased. This pattern persisted regardless of serum level. The serum concentrations used were 10% Fetal Bovine Serum (FBS), which represented a non-stressed system, with 2.5 and 1% FBS concentrations used to simulate stressed environments. Assessment for apoptosis, programmed cell death, resulted in higher than baseline levels in cells exposed to WTC dust in both MRC-5 and WI-38 human lung fibroblasts. Conclusion/Recommendations: In summary, results showed that exposure to WTC dust led to decreased cell proliferation and increased apoptosis levels. These findings evidence need for future research regarding mutagenic properties of World Trade Center dust.

Microanatomy and Histochemistry of the Salt Glands of the Kentish Plover, Charadrius alexandrines (Aves, Charadriidae)

Problem statement: Histological and histochemical investigations on the salt glands of birds are very limited. The present study was performed to characterize the microanatomy and histochemistry of the salt glands of the Kentish plover (Charadrius alexandrines). Approach: Salt glands of the bird under study were fixed, dehydrated, cleared, impregnated and blocked out by paraffin wax. Paraffin sections were utilized in histological and histochemical examinations to characterize the structure and chemical contents of these glands. Results: The Kentish plover had a well developed bilateral seromucous salt glands lie in the supraorbital depression of the frontal bone. Each gland is about 0.18 g and had lobular arrangement consisted of one cell thick secretory tubules enmeshed in tiny blood capillaries. The tubules radiate from central canals that drain in a main duct of 3-4 mm in length and opens into the external nares. The secretory tubules were lined by a single layer of principal cells and opens in intercalated ducts followed by striated ducts. The employed histochemical tests indicated that seretory tubules elaborate proteins and acid mucosubstances but are devoid of glycogen and neutral mucosubstances while the intertubular stroma showed metachromatic, alcianophilic and PAS reactivity. Conclusion/Recommendations: The results of the present study revealed that salt glands of Kentish plover are active adaptive tool of osmoregulation to control the amount of water needed by this bird. More research is needed to understand the adaptation of the seabirds to the physiological stress of the salt load.

Characteristics of a Novel Highly Thermostable and Extremely Thermophilic Alkalitolerant Amylase from Hyperthermophilic Bacillus Strain HUTBS71

Problem statement: This study reported the purification and characterization of a novel highly thermostable alkaline amylase from a newly isolated Bacillus strain HUTBS71. Approach: The enzyme was purified using ammonium sulfate precipitation, ion exchange and gel filtration chromatography. Results: Maximum amylase activity (72 U mL^-1) was obtained at 100�C after 10 min of incubation. The enzyme was purified 24 fold with 12.5% yield and showed a monomer band with a molecular weight of 58.8 kDa by SDS-PAGE. This enzyme exhibited maximum activity at pH and temperature, 7.8 and 100�C, respectively. It performed stability over a broad range of pH and temperature, 5.2-10.0 and 80-115�C, respectively. The half-life of the enzyme at 90 and 100�C was estimated to be 3 h. The activation energy of denaturation of purified enzyme was 2.53 kJ moL^-1. The enzyme was activated by 5 mM of CoCl₂, MgSO₄, MnCl₂, ZnSO₄ and MnSO₄ (relative activity was 133, 126, 133, 106.6 and 103%, respectively). It was strongly inhibited by CuSO₄ and CdCl₂ but less affected by NaCl, CaCl₂, FeCl₃, ZnCl₂ and EDTA. Conclusion: The present purified amylase therefore could be defined as a highly thermostable, extremely hyperthermophilic and alkalitolerant with new properties make the present enzyme applicable for many starch processing and food industries.

Detection of Phytoplasma on Indian Fig (Opuntia ficus-indica Mill) in Mexico Central Region

Problem statement: The Indian fig (a species of prickly pear cactus), has been known as Nopal, comprises an approximate area of 100,000 ha, in plantations used for human consumption. �Pyramids� Indian fig area located in the northeastern State of Mexico has been an important Indian-fig area in the country, with 15810 ha, where a phytoplasma has been consistently present in symptomatic plant. Approach: An unknown symptomatology in the Indian fig (prickly pear cactus) (Opuntia ficus-indica Mill) was analyzed through grafting and a nested-PCR reaction and graft on healthy plants grown in a greenhouse. Results: The symptoms found, deforming, buds proliferation, thickening and heart-shaping in cladodes, with arrested plant growth and deep yellowing of cladodes, were all attributed to the presence of a phytoplasma given the amplification of a 1200 pb fragment of the 16S rRNA gene using primers R16 F2/R2 and R16F2n/R2 and 80% of phytoplasma transmission efficiency of successful grafts. Conclusion: Although the symptoms observed did not completely match those described for this organism in the region, a 1200 pb fragment was amplified and PCR products restriction analysis leading us to assume that the phytoplasma corresponds to subgroup 16Srll, previously reported for other crops in others world regions.

Four Dimensional (4-D) BioChemInfoPhysics Models of Cardiac Cellular and Sub-Cellular Vibrations (Oscillations)

Problem statement: Cardiovascular Diseases (CVD) continued to be the leading cause of death. Failure or abnormal cardiac cellular or sub-cellular vibrations (oscillations) could lead failure or abnormal heart beats that could cause CVD. Understanding the mechanisms of the vibrations (oscillations) could help to prevent or to treat the diseases. Scientists have studied the mechanisms for more than 100 years. To our knowledge, the mechanisms are still unclear today. In this investigation, based on published data or results, conservation laws of the momentum as well as the energy, in views of biology, biochemistry, informatics and physics (BioChemInfoPhysics), we proposed our models of cardiac cellular and sub-cellular vibrations (oscillations) of biological components, such as free ions in Biological Fluids (BF), Biological Membranes (BM), Ca++H+ (Ca++ and Na+K+) ATPases, Na+Ca++ exchangers (NCX), Ca++ carriers and myosin heads. Approach: Our models were described with 4-D (x, y, z, t or r, , z, t) momentum transfer equations in mathematical physics. Results: The momentum transfer equations were solved with free and forced, damped, un-damped and over-damped, vibrations (oscillations). The biological components could be modeled as resonators or vibrators (oscillators), such as liquid plasmas, membranes, active springs, passive springs and active swings. Conclusion: We systematically provided new insights of automation (ignition and maintain), transportation, propagation and orientation of the cardiac cellular and sub-cellular vibrations (oscillations) and resonances, with our BioChemInfoPhysics models of 4-D momentum transfer equations. Our modeling results implied: Auto-rhythmic cells (Sinoatrial Node Cells (SANC), Atrioventricular Node Cells (AVNC), Purkinje fibers), non-Auto-rhythmic ventricular myocytes and their Sarcoplasmic Reticulums (SR) work as Biological Liquid Plasma Resonators (BLPR). The resonators were biological clocks and mainly made of BF, BM and BM Transporters (BMT) that had mutually adapted and produced Biological Liquid Plasma Resonance Frequencies (BLPRF) for the resonators during their natural evolution. The resonators naturally vibrate (oscillate) near the SANC SR BLPRF that had the highest BLPRF among them.

Enhanced Survival and Nodule Occupancy of Pigeon pea Nodulating Rhizobium sp. ST1 expressing fegA Gene of Bradyrhizobium japonicum 61A152

Problem statement: Rhizobial isolates belonging to genera (Rhizobium sp. and Mesorhizobium sp.) in our laboratory produced only catecholate type of siderophores. Although FhuA and FegA (ferrichrome receptors) homologs were found to be present in the sequenced genomes of few rhizobia (e.g., 1 in R. etli and 2 in Mesorhizobium sp. BNC1), laboratory isolates of the corresponding genera failed to utilize ferrichrome, a siderophore which is present in nanomolar concentrations in the soil. This inability was considered as a negative fitness factor with respect to rhizospheric colonization by these rhizobia. Approach: The 2.4 kb fegA gene (encoding ferrichrome receptor) was amplified along with its native promoter from Bradyrhizobium japonicum 61A152 and cloned in a broad host range plasmid vector pUCPM18. The plasmid construct pFJ was transferred by conjugation into Rhizobium sp. ST1 to give transconjugant ST1pFJ12. The consequence of FegA expression on the transconjugant was tested under lab and soil conditions, using physiological experiments. Results: Ability of the transconjugant ST1pFJ12 to utilize ferrichrome and expression of a 79 kD protein band on the outer membrane of the transconjugant confirmed FegA expression. Transconjugant ST1pFJ12 exhibited increased growth rate as compared to the parent strain ST1, in minimal media containing ferrichrome as the sole iron source, confirming the positive effect of FegA expression. Inoculation of pigeon pea seedlings with transconjugant ST1pFJ12 led to a marked increase in plant growth parameters as compared to plants inoculated with the parent strain ST1, the effect being more pronounced when Ustilago maydis, a ferrichrome producer was co-inoculated in the systems. Nodule occupancy on pigeon pea plant when inoculated with the transconjugant ST1pFJ12 alone was 57% which increased to 66% when co-inoculated with U. maydis as compared with 37 and 30% respectively, seen with parental strain ST1 inoculation. Conclusion: The clear increase in nodule occupancy and higher rhizospheric colonization by the fegA transconjugants, presented in this study together with the previous research reported from our laboratory, led us to conclude that ferrichrome utilization ability played an important role in the rhizospheric colonization of the bioinoculant strains. Testing the ability to utilize hydroxamate siderophores therefore, holds prime importance in selecting an efficient biofertilizer strain.

Epidemiology of Human Herpesvirus Type 8 Infection in Cardiopathic Patients

Problem statement: The possible contribution of viruses to vascular pathology is still a controversial issue. Human herpesvirus type 8 (HHV-8) has been suggested to participate to the pathogenetic events associated with atherosclerotic lesion establishment and progression. Recently, a high incidence of infection of HHV-8 (11%) has been verified in the island of Sardinia. The aim of this study was to evaluate a possible relationship between the HHV-8 infection and cardiovascular diseases in the South of Sardinia. Approach: The presence of HHV-8 genome was detected in DNA extracted from peripheral leucocytes, by nested-PCR and Southern blotting, in either acute or chronic cardiopathic patients (n = 180); healthy blood donors were examined as controls (n = 108). Results: The results demonstrated a significant increase (p = 0.035) in HHV-8 DNA isolation from cardiopathic patients (22.8%) in comparison to healthy controls (12.0%). Conclusion: HHV8 infection can be considered, among others, as an additional risk factor for cardiovascular disease development, although it was not necessarily the starting cause. More extensive studies were needed to define the exact role of HHV-8 infection in cardiopathic patients.

Arthropods the Medicinal Importance in Brazil: Retrospective Epidemiological Information about Accidents Involving these Animals

Kidney Function Indices in Mice after Long Intake of Agaricus brasiliensis Mycelia (=Agaricus blazei, Agaricus subrufescens) Produced by Solid State Cultivation

The Hypoglycemic Properties of BAE Maca Max Preparation

Bheri-A Unique Example of Biological Complex System

Problem statement: This study is a unique attempt to characterize Bheri (shallow flat bottom waste water fed fishery) as a complex biological system. Approach: The characterization was done both at the qualitative and the quantitative levels. The diverse microbial community and the associated emergent behaviors resulting in integrated resource recovery by the Bheris were analyzed under the lens of complexity to gain an understanding about the qualitative features. To carry out quantitative characterization, ideas of scaling and power law relationships were emphasized through statistical analysis of observed data. Results: On comparing the plankton diversity of the Bheris with rain water and waste water fed ponds located within Calcutta (India) as well as Dhaka (Bangladesh), the former indicated clear evidence of exhibiting power law behavior (which is a strong signature of complexity). The adequacy of observations was reflected in the saturation of the curves obtained on plotting the number of observations against the Operational Taxonomic Unit (OTU). Conclusion: This study clearly reveals Bheri as a biological complex system both at qualitative and quantitative levels as compared to rain water as well as waste water fed ponds.

Does Predator Go for Size Selection or Preferential Toxic-Nontoxic Species Under Limited Resource?

Problem statement: electivity is common in predator-prey interaction but the selection mechanism is still unexplored and a debatable issue in modern theoretical and experimental ecology for numerous species across the globe. In present investigation we emphasized the hypothesis that the zooplankton is less inclined to opt the food based on size selectivity criteria than the preferential selectivity for the safe non-toxic food species. Approach: As a test bed we select one nontoxic phytoplankton (Chaetocerous gracilis), one toxic phytoplankton (Microcystis aeruginosa) and one zooplankton (Artemia salina). Initially the experiment is setup through the small batch cultures of Nontoxic (NTP) and toxic Phytoplankton (TPP). Both the strains of phytoplankton are collected from the deltaic region of river Subarnarekha (87�31�E and 21�37�N) and the isolation is done in the laboratory. Similarly batches of zooplankton (Brand: Red Top, USA) are also hatched and maintained at optimal conditions in the laboratory. We set off the experiments with the physical parameters viz. Photo period: 12: 12 L: D cycle, Temperature: 26-27�C, Salinity: 10 ppt and pH of the medium 7.5. To evaluate our hypothesis in restricted environment we have introduced the zooplankton in a 3 liter beaker with 75: 25 (TPP: NTP) food ratio. Biological activities (feeding) are monitored for each of the species with regular recorded biomass count on each experimental day till the predator population goes to extinct. Results: The mean biomass profile of zooplankton remains more or less constant at the initial stage but a sharp decline trend has been observed after the 4th day of the experiment. A similar trend has been observed for the mean biomass profile of NTP leading the population toward extinction after 6th experimental day. The entire mean biomass profile trend of TPP can be interpreted as a convolution of three growth pulses viz., initially positive, followed by a negative and terminating with a positive growth. To evaluate the bias in the result of experiment we have estimated the variance levels of sample biomasses for each of the experimental time points for each of the three species. Conclusion: The observed stable nature of the zooplankton biomass may be due to initial NTP uptakes but a sudden decline suggests that they are forced to feed on the TPP for survival. In absence of grazing pressure, TPP initially showed a mild positive growth but when the predator switch to TPP for food it shows a negative growth and finally due to rapid mortality of zooplankton and excretal nutrient input the growth rate again kicks up. In summary we conclude that the zooplankter (Artemia salina) can discriminate toxic and nontoxic food species and more inclined toward the non-toxic species if the resource available. But shortage of nontoxic species, force them to feed on toxic one, in spite of drastic adverse effect on its survival.

Complexity in Human Perception of Brightness: A Historical Review on the Evolution of the Philosophy of Visual Perception

Problem statement: The �eye-brain� complex, which contributes maximally to visual perception, is no doubt a very interesting object for complexity study. In this review we shall try to present some of its aspects in perceiving brightness. It is a well-known fact that the perceived brightness of any surface depends on the brightness of the surfaces that surround it, a phenomenon termed as brightness induction. Several studies reveal that brightness contrast and brightness assimilation are two opposite phenomena in brightness induction. The former can be explained through the microscopic neural circuits that emanate from the retinal ganglion cells and converge on to primary visual cortex i.e. through a bottom-up approach, something which however fails till date to account for the later. In search of a unified theory of brightness induction, a top-down approach has often been suggested. However, the mechanism of brightness induction evident in several optical illusions, is not yet understood even after 200 years of intense research that saw George Berkeley, Maxwell, Helmholtz and the modern Gestalt school, that include both the intrinsic image theorists as well as the anchoring model theorists, following the �top-down� approach on one hand and Weber, Fechner, Mach, succeeded by the modern contrast theorists following the �bottom-up� approach on the other. Approach: In this review, we presented a historical perspective of the evolution of human concepts about the perception of brightness. We tried to capture the two essential philosophical trends among the scientists in understanding the phenomenon of brightness induction. The problems with idealist approach as well as the limitations of the mechanical materialist approach, have been pointed out in the light of the facts that, nature in general and complex systems in particular, are intrinsically dialectic in nature. Results: A proposal had been put forward that the path of dialectical materialism is the possible way out for the present philosophical crisis. Conclusion: Lateral inhibition based contrast theories need to be substantiated not only by the basic law of dialectics on which it rests upon viz., the unity of opposites, but also through the incorporation of the other dialectical laws like connectivity, quantity-quality transition and negation of the negation, so as to challenge all sorts of mysticisms in vision science and in brightness perception domain. Some recent researches both in experimental psychophysics as well as in mathematical modeling, that have been discussed or referred to in this review, are showing signs of such a development. In order to ensure that such synthesis should be dialectic and not eclectic, it would require identifying the proper mathematics towards quantitatively representing complex phenomena, a mathematics that can quantify the interaction between the part and the whole, through dialectical rules.

Stability Analysis of a Class of Three-Neuron Delayed Cellular Neural Network

Problem statement: In this study linear stability of a class of three neuron cellular network with transmission delay had been studied. Approach: The model for the problem was first presented. The problem is then formulated analytically and numerical simulations pertaining to the model are carried out. Results: A necessary and sufficient condition for asymptotic stability of trivial steady state in the absence of delay is derived. Then a delay dependent sufficient condition for local asymptotic stability of trivial, steady state and sufficient condition for no stability switching of trivial steady for such a network are derived. Numerical simulation results of the model were presented. Conclusion/Recommendations: From numerical simulation, it appears that there may be a possibility of multiple steady states of the model. It may be possible to investigate the condition for the existence of periodic solutions of the non-linear model analytically.

Asymptotic Behavior of an Artificial Neural Network Defined on Multipartite Directed Graph

Problem statement: Artificial Neural Network (ANN) are simple models to mimic some essential features of the complex central nervous system. ANN models are realistic due to their inherent stochastic nature of neural computation and strong synchronicity. Different ANN models are associated with directed and signed graphs. The present study proceeded by relaxing certain simplifying assumptions in the ANN model. Approach: It was assumed that the connected graph associated with the ANN is a multipartite directed graph whose connection comprising of four blocks and two blocks are either both symmetric or both anti symmetric. The convergence of such network was studied in the present research with the help of Lyapunov functional. Results: Attractors (fixed points) of such ANN and also limit cycles of different orders are investigated. Bounds of transient length of the neural network were also calculated. Numerical simulation in support of the results was also depicted. Conclusion: It was shown that under synchronous updating rule such networks converge to a fixed point or to a limit cycle of period 2 or 4. The bound of transient length was discussed. Conclusions were drawn from the simulation studies carried out in support of the results.

Hypoglycaemic Effects of Dietary Intake of Ripe and Unripe Lycopersicon esculentum (Tomatoes) on Streptozotocin-Induced Diabetes Mellitus in Rats

Ripe and unripe tomatoes have been implicated in prevention of chronic diseases such as cancer probably due to their antioxidant, antibiotic, antifungal and anti-inflammatory properties. Problem statement: This study was designed to investigate whether ripe and unripe tomatoes will have hypoglycaemic effect in a chronic disease such as diabetes mellitus that has been characterized with hyperglycaemia. Approach: Twenty albino Wistar rats were divided into 4 groups (2 control and 2 test groups) of 5 rats each. The normal and diabetic control groups were given citrate buffer (intraperitoneally) and normal rat chow and 65 mg kg^-1 streptozotocin (intraperitoneally) and normal rat chow respectively. The test groups were given 65 mg kg^-1 streptozotocin via intraperitoneal route and either a mixture of ripe or unripe tomato and normal rat chow. In all groups, the blood samples were obtained at the tail vein of the animals and the fasting blood glucose level were monitored and determined on the 1st, 3rd and 14th day of consumption of different feed combinations. Results: There was significant difference in blood glucose level in animals fed on ripe and unripe Lycopersicon esculentum (tomato) compared to the normal and diabetic control groups on the 3rd and 14th day without significant difference on the 1st day. Conclusion: Both high-lycopene ripe tomato and high-tomatine unripe tomato have hypoglycaemic effect in diabetic mellitus at short period of dietary intake therefore this suggest that consumers may benefit by not only eating high-lycopene ripe tomatoes, but also high-tomatine unripe tomatoes.

The Relationship between Serum Cotinine Levels and Periodontal Status

Problem statement: Smoking plays a significant role in the development of periodontal disease. Quantitative relation between smoking and increased severity of periodontal disease, by means of biochemical marker has not been described in Malaysian population. The present study was designed to apply serum cotinine measurement as a quantitative method to evaluate smoking levels in Malaysian patients and to correlate these levels with the severity of periodontal disease. Approach: The study group consisted of 80 healthy individuals (20-64) year, Current Smokers 26, Non Smokers 27 and Former Smokers 27. The subjects were then asked to complete a questionnaire including the demographic, socioeconomic status, medical history and history of cigarette smoking. The periodontal variables recorded were amount of Visible Plaque score, gingival bleeding Index and community periodontal index. Samples of blood �10 mL� were obtained in vacutainer tubes containing EDTA for quantitative analysis of serum levels of cotinine. The serum samples were analyzed for cotinine content by means of a competitive-inhibition ELISA technique. Results: Current smokers represent the highest mean cotinine serum level, 95.5 ng mL^-1, compared to former smokers, 35.5 ng mL^-1 and non smokers, 22.9 ng mL^-1. The mean serum cotinine level in periodontally healthy patient showed the highest cotinine level (84 ng mL^-1) followed by the gingivitis patients (68 ng mL^-1) and (50 ng mL^-1) for periodontitis patients. Conclusion: The present observations clearly indicate an association between smoking, periodontal disease clinical parameters �plaque, gingival bleeding scores� and cotinine serum levels in current smokers. Cotinine serum levels doesn�t affected by the existence or the severity of periodontal disease.

The Incidence of Fibromyoma and Polycystic Ovary Syndrome in Women in Trinidad (2000-2003)

Problem statement: Before this study was done there were no reports of similar studies in Trinidad whereas similar study had been reported from other parts of the World including the Caribbean sub-region. The present study was thus designed to investigate the incidence and demographics of leiomyomata and polycystic ovary syndrome in women in two health institutions in Trinidad during the period from 2000-2003, inclusive. The study also sought to establish the prevalence of the established risk factors viz. age, ethnicity, parity and gravidity and to examine their relationship with the two disease conditions. Approach: The study population included only women who were diagnosed with or treated for these conditions at the Mt. Hope Medical Science Complex and San Fernando General Hospital in Trinidad and Tobago during the specified period. Results: The most common presenting complaints were vaginal bleeding and colicky lower abdominal pain for fibroids and polycystic ovarian syndrome respectively. The majority of the fibroid cases were aged between 40 and 49 years. Similarly most of the patients with polycystic ovary were aged between 20 and 29 years. Hysterectomy was the most frequent surgical intervention. Prior to this, patients were placed on haematinics for anaemia and analgesics for pain. Conclusion: The present study has provided the database that could be harnessed in improving the health care delivery system for the population of Trinidad in different ways as discussed in the text of the article.

The Use of Insects as Human Food in Zambia

Problem statement: The life cycle and culture structure of two commonly eaten worms in Zambia (Isoberlinia paniculata and Miombo/Mopani) were evaluated. The worms were grown on an artificial medium to evaluate the potential of producing them on a commercial scale. Approach: An interesting characteristic of the worms studied was that they reached their maximum weight and maximum length at the same time. Results: The larvae started to decrease in weight soon after reaching their maximum size suggesting that they should be harvested shortly before reaching their maximum length (36 days old). Only 10% mortality was observed with the older larvae of the Miombo/Mopani worm. A system where eggs are separated from adults and hatched in separate chambers would alleviate the danger of losing the population due to microbial infection. The high moisture content of the live larvae (60.5-60.9%) could cause handling and storage problems. Drying and grinding the larvae would reduce them to easily manageable forms and would improve their marketability as a novel food. The results obtained from this study showed the potential of using these insects as a protein source for human consumption. They had structured animal protein that contained the essential amino acids, lipids, vitamins, minerals and energy required for human growth and their nutrition contents are comparable to those of conventional foods. These worms are harvested from trees in Africa but the industry is facing droughts and overexploitation that has lead to local extinctions in several areas. Conclusion/Recommendations: Therefore, further research is required to evaluate their growth on low substrates and to assess the effects of environmental parameters such as temperature, relative humidity, CO₂ and heat production on food consumption and protein yield and quality. This information will aid in the design of an optimal commercial insect production system. Appropriate processing and marketing procedures would also insure the sustainability of the industry.