scholarly journals Decompression sickness risk in rats by microbial removal of dissolved gas

1998 ◽  
Vol 275 (3) ◽  
pp. R677-R682 ◽  
Author(s):  
Susan R. Kayar ◽  
Terry L. Miller ◽  
Meyer J. Wolin ◽  
Eugenia O. Aukhert ◽  
Milton J. Axley ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
High Pressures ◽  
Decompression Sickness ◽  
Body Burden ◽  
The Body ◽  
Dissolved Gas ◽  
Hyperbaric Chamber ◽  
Methanobrevibacter Smithii ◽  
Water Rate ◽  
Microbial Removal

We present a method for reducing the risk of decompression sickness (DCS) in rats exposed to high pressures of H2. Suspensions of the human colonic microbe Methanobrevibacter smithii were introduced via a colonic cannula into the large intestines of the rats. While the rats breathed H2in a hyperbaric chamber, the microbe metabolized some of the H2diffusing into the intestine, converting H2and CO2to methane and water. Rate of release of methane from the rats, which was monitored by gas chromatography, varied with chamber H2pressure. This rate was higher during decompression than during compression, suggesting that during decompression the microbe was metabolizing H2stored in the rats’ tissues. Rats treated with M. smithii had a 25% (5 of 20) incidence of DCS, which was significantly lower ( P < 0.01) than the 56% (28 of 50) incidence of untreated controls, brought on by a standardized compression and decompression sequence. Thus using a microbe in the intestine to remove an estimated 5% of the body burden of H2reduced DCS risk by more than one-half. This method of biochemical decompression may potentially facilitate human diving.

Hyperbaric treatment for decompression sickness: current recommendations

2019 ◽  
pp. 685-693
Author(s):  
Richard E. Moon ◽  
◽  
Simon Mitchell ◽  
◽  
Keyword(s):  
Decompression Sickness ◽  
Ambient Pressure ◽  
Dissolved Gas ◽  
Hyperbaric Chamber ◽  
Hyperbaric Treatment ◽  
Hypobaric Chamber ◽  
Rapid Ascent ◽  
Gas Pressures

Rationale Decompression sickness (DCS, “bends”) is caused by formation of bubbles in tissues and/or blood when the sum of dissolved gas pressures exceeds ambient pressure (supersaturation) [1]. This may occur when ambient pressure is reduced during any of the following: • ascent from a dive; • depressurization of a hyperbaric chamber; • rapid ascent to altitude in an unpressurised aircraft or hypobaric chamber; • loss of cabin pressure in an aircraft [2] and • during space walks.

scholarly journals Maternal Body Burden of Organochlorine Pesticides and Dioxins

1999 ◽  
Vol 82 (3) ◽  
pp. 716-724 ◽  
Author(s):  
Reiko Nakagawa ◽  
Hironori Hirakawa ◽  
Takao Iida ◽  
Takahiko Matsueda ◽  
Junya Nagayama
Keyword(s):  
Gas Chromatography ◽  
Breast Milk ◽  
Organochlorine Pesticides ◽  
Body Burden ◽  
Food Habit ◽  
The Body ◽  
Electron Capture Detection ◽  
Polychlorinated Dibenzofuran ◽  
High Resolution Gas Chromatography ◽  
Mother’S Age

Abstract To investigate the body burden of organochlorine pesticides and dioxins in Japanese women,125 milk samples were collected from 41 mothers in 1994, 42 in 1995, and 42 in 1996. Ofthe 125 samples, 82 were from primipara mothers (first delivery) and 43 were from multipara mothers (second or later delivery). By using capillary gas chromatography with electron capture detection, β-HCH and p,p′-DDE were detected as the major chlorine pesticides in human milk. Average levels of β-HCH and p,p′-DDE were 475 and 368 ng/g lipid, respectively, in primipara breast milk, 314 and 259 ng/g lipid in multipara breast milk, and 420 and 330 ng/g lipid in total breast milk. Dieldrin, heptachor epoxide, oxychlordane, trans-chlordane, and cis-chlordane were detected at lower average levels of 3, 4, 34, 41, and 5 ng/g lipid, respectively. By using high-resolution gas chromatography with mass spectrometric detec tion, dioxins were detected in all samples. Average levels of total polychlorinated dibenzo-p-dioxin (PCDD), total polychlorinated dibenzofuran (PCDF), total PCDD + PCDF, total coplanar polychlorinatedbiphenyl (CoPCB), and total dioxin were 10.0, 7.8, 17.7, 9.9, and 27.5 TEQ (toxic equivalent) pg/g lipid, respectively, in primipara breast milk; 7.0, 5.8, 12.8, 7.3, and 20.1 TEQ pg/g lipid in multipara breast milk; and 8.9, 7.1, 16.1, 8.9, and 25.0 TEQ pg/g lipid in total breast milk. In primipara breast milk, significant correlations were found among levels of β-HCH, p,p’-DDE, total PCDD-TEQ, total PCDF-TEQ, total CoPCB-TEQ, and total TEQ except for less correlation between p,p’-DDE and total PCDF-TEQ. Levels of these analytes also significantly increased depending on mother’s age, except for total Co-PCB-TEQ. For the correlation with food habit, the only positive correlation was between total PCDF-TEQs and fish intake.

Fast Method for the Determination of Residual Solvents in Radiopharmaceutical Products

2017 ◽  
Vol 68 (4) ◽  
pp. 666-670 ◽  
Author(s):  
Mirela Mihon ◽  
Catalin Stelian Tuta ◽  
Alina Catrinel Ion ◽  
Dana Niculae ◽  
Vasile Lavric
Keyword(s):  
Gas Chromatography ◽  
Control Method ◽  
Limit Of Detection ◽  
The Body ◽  
Biologically Active ◽  
Injection Technique ◽  
Fast Method ◽  
Residual Solvent ◽  
Residual Solvents

The aim of this work was the development and validation of a fast analytical method to determine the residual solvents content in radiopharmaceuticals such as: 18F-Fluorodeoxyglucose (18F-FDG), 18F-Fluoroestradiol (18F-FES), 18F-Fluorothymidine (18F-FLT),18F-Fluoromisonidazole (18F-FMISO). Radiopharmaceuticals are radioactive preparations for medical purposes used in nuclear medicine as tracers in diagnostic imaging and treatment of certain diseases. Positron Emission Tomography (PET) is a medical imaging technique that consists in introducing into the body of a small amount of a biologically active chemical compound labelled with a short lived positron-emitting radioisotope (18F, 11C, 68Ga). Residual solvents are critical impurities in radiopharmaceuticals that can affect labelling, stability and physicochemical properties of drugs. Therefore, the determination of these solvents is essential for quality control of radiopharmaceuticals. Validation of the control method for residual solvents by gas chromatography is referred by the European Pharmacopoeia using a special injection technique (head space). The parameters of the method, which comply with International Conference on Harmonization guidelines, are: accuracy, precision, linearity, limit of detection, limit of quantification and robustness. The proposed method (direct gas chromatography injection) proved to be linear, precise, accurate and robust. Good linearity was achieved for all the solvents and correlation coefficients (R2) for each residual solvent were found more than 0.99.

Effect of Sample Storage Conditions on Body Burden Analysis of Organic Contaminants in Unionid Mussels

1992 ◽  
Vol 27 (4) ◽  
pp. 833-844 ◽  
Author(s):  
Micheline Hanna
Keyword(s):  
Organic Contaminants ◽  
Body Burden ◽  
Storage Conditions ◽  
The Body ◽  
Sample Storage ◽  
Pcb Congeners ◽  
Unionid Mussels ◽  
Group A ◽  
The Difference ◽  
Group B

Abstract In order to quantitatively assess the effect of sample storage conditions on the body burden analysis of organic contaminants, a comparative analysis was carried out on the unionid mussel Elliptic complanata. The mussels were divided into two groups, each with distinct storage conditions, while Group A was kept in the freezer at −20°C, Group B was kept in the refrigerator for five days at 5°C. All the compounds present in the control were also present in Group B samples. Analysis of the organic contaminants in each of these two groups showed that for total PCB concentrations, the two treatments were not significantly different; however when compared individually 6 of the 13 PCB congeners showed significant differences. The observed differences were relatively small for individual PCB congeners (7.1 to 15.3%), higher for chlorobenzenes (10.5 to 36.4%), and yet higher for HCE (44.1%); the difference for HCE, although large is nevertheless not significant, even if only marginally so.

Abdominal decompression illness following repetitive diving: a case report and review of the literature

2019 ◽  
pp. 211-215
Author(s):  
Peter Beale ◽  
Levi Kitchen ◽  
W.R. Graf ◽  
M.E. Fenton ◽  
Keyword(s):  
Case Report ◽  
The Body ◽  
Decompression Illness ◽  
Review Of The Literature ◽  
Hyperbaric Chamber ◽  
Foreign National ◽  
Biochemical Effects ◽  
Elapsed Time ◽  
Nitrogen Bubbles ◽  
Abdominal Decompression

The complete pathophysiology of decompression illness is not yet fully understood. What is known is that the longer a diver breathes pressurized air at depth, the more likely nitrogen bubbles are to form once the diver returns to surface [1]. These bubbles have varying mechanical, embolic and biochemical effects on the body. The symptoms produced can be as mild as joint pain or as significant as severe neurologic dysfunction, cardiopulmonary collapse or death. Once clinically diagnosed, decompression illness must be treated rapidly with recompression therapy in a hyperbaric chamber. This case report involves a middle-aged male foreign national who completed three dives, all of which incurred significant bottom time (defined as: “the total elapsed time from the time the diver leaves the surface to the time he/she leaves the bottom)” [2]. The patient began to develop severe abdominal and back pain within 15 minutes of surfacing from his final dive. This case is unique, as his presentation was very concerning for other medical catastrophes that had to be quickly ruled out, prior to establishing the diagnosis of severe decompression illness. After emergency department resuscitation, labs and imaging were obtained; abdominal decompression illness was confirmed by CT, revealing a significant abdominal venous gas burden.

scholarly journals Fuzzy Algorithm for Power Transformer Diagnostics

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Nitin K. Dhote ◽  
Jagdish B. Helonde
Keyword(s):  
Gas Chromatography ◽  
Fuzzy Inference System ◽  
Fuzzy Inference ◽  
Power Transformer ◽  
Gas Analysis ◽  
Transformer Oil ◽  
Dissolved Gas ◽  
Inference System ◽  
Incipient Faults ◽  
The World

Dissolved gas analysis (DGA) of transformer oil has been one of the most reliable techniques to detect the incipient faults. Many conventional DGA methods have been developed to interpret DGA results obtained from gas chromatography. Although these methods are widely used in the world, they sometimes fail to diagnose, especially when DGA results fall outside conventional methods codes or when more than one fault exist in the transformer. To overcome these limitations, the fuzzy inference system (FIS) is proposed. Two hundred different cases are used to test the accuracy of various DGA methods in interpreting the transformer condition.

scholarly journals Human Body Burden of Heavy Metals and Health Consequences of Pb Exposure in Guiyu, an E-Waste Recycling Town in China

2021 ◽  
Vol 18 (23) ◽  
pp. 12428
Author(s):  
Wenlong Huang ◽  
Xiaoling Shi ◽  
Kusheng Wu
Keyword(s):  
Heavy Metals ◽  
Body Burden ◽  
Local Environment ◽  
Waste Recycling ◽  
The Body ◽  
Health Consequences ◽  
Long Term Effects ◽  
Adaptive Immune ◽  
Pb Exposure

Guiyu accommodates millions of tons of e-waste from overseas and domestic sources each year and is notorious for its e-waste dismantling industry. As a consequence, Guiyu has been described as “the world’s most toxic place” and “junk town”. Informal e-waste recycling activities have caused severe pollution to the local environment and are associated with extensive health problems to the residents. This review provides updated insights on the body burden of heavy metals derived from e-waste and health outcomes resulted from lead (Pb) exposure. The review identified that Guiyu has been highly contaminated by heavy metals, especially Pb. Excessive exposure to Pb has been associated with multi-system and long-term effects in neonates and children, covering nervous, cardiovascular, adaptive immune, and hematologic systems as well as chromosome and DNA damage. Our review indicates strong associations that emphasize the need to develop strong regulations for prevention of exposure and health consequences in Guiyu and similar sites around the world.

Influence of Several Chelating Agents on the Distribution and Binding of Cadmium in Rats

1987 ◽  
Vol 6 (6) ◽  
pp. 451-458 ◽  
Author(s):  
W. Rau ◽  
F. Planas-Bohne ◽  
D.M. Taylor
Keyword(s):  
Molecular Weight ◽  
Binding Site ◽  
High Molecular Weight ◽  
Metal Concentration ◽  
Chelating Agents ◽  
Body Burden ◽  
The Body ◽  
Sprague Dawley ◽  
Sprague Dawley Rats ◽  
Human Use

1 Male Sprague-Dawley rats were injected with 109CdCl2 (3 μmol Cd/kg) and killed between 1 h and 200 d afterwards. Metal concentration in the critical organs, i.e. liver and kidneys decreased very slowly. Within the cells Cd is found mainly in the cytosol and — at very early times — in the nuclei. Within the cytosol of the liver most of the metal is initially bound to proteins with high molecular weight but as early as 3 h after incorporation more than 90% is bound to metallothionein which is always the main binding site in the kidneys. 2 Of the chelating agents tested only BAL and Puchel were able to reduce the body burden significantly. Both are lipophilic substances. Puchel cannot reduce the kidney Cd burden but removes Cd from the liver only while BAL is effective in both organs. Both chelating agents exert their effects at doses which are too near to the LDso to be considered as safe enough for human use.

scholarly journals Exploring the complex interplay in the regulation of cardiac pathophysiological functions by protein kinases and phosphatases

2021 ◽  
Vol 6 (4) ◽  
pp. 165-170
Author(s):  
Dr Chrysanthus Chukwuma Sr
Keyword(s):  
Heart Failure ◽  
Cardiovascular System ◽  
Protein Kinases ◽  
Body Burden ◽  
The Body ◽  
Complex Interplay ◽  
Physiological Processes ◽  
Progressive Heart Failure ◽  
Drug Lead ◽  
Cardiac Excitation

Cardiovascular disease manifests as an intricately complex entity presenting as a derangement of the cardiovascular system. Cardiac or heart failure connotes the pathophysiological state in which deficient cardiac output compromises the body burden and requirements. Protein kinases regulate several pathophysiological processes and are emerging targets for drug lead or discovery. The protein kinases are family members of the serine/threonine phosphatases. Protein kinases and phosphatases are pivotal in the regulatory mechanisms in the reversible phosphorylation of diverse effectors whereby discrete signaling molecules regulate cardiac excitation and contraction. Protein phosphorylation is critical for the sustenance of cardiac functionalities. The two major contributory ingredients to progressive myocardium derangement are dysregulation of Ca2+processes and contemporaneous elevated concentrations of reactive oxygen species, ROS. Certain cardiac abnormalities include cardiac myopathy or hypertrophy due to response in untoward haemodynamic demand with concomitant progressive heart failure. The homeostasis or equilibrium between protein kinases and phosphatases influence cardiac morphology and excitability during pathological and physiological processes of the cardiovascular system.

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