55 research outputs found
Systematic Review of Potential Health Risks Posed by Pharmaceutical, Occupational and Consumer Exposures to Metallic and Nanoscale Aluminum, Aluminum Oxides, Aluminum Hydroxide and Its Soluble Salts
Aluminum (Al) is a ubiquitous substance encountered both naturally (as the third most abundant element) and intentionally (used in water, foods, pharmaceuticals, and vaccines); it is also present in ambient and occupational airborne particulates. Existing data underscore the importance of Al physical and chemical forms in relation to its uptake, accumulation, and systemic bioavailability. The present review represents a systematic examination of the peer-reviewed literature on the adverse health effects of Al materials published since a previous critical evaluation compiled by Krewski et al. (2007).
Challenges encountered in carrying out the present review reflected the experimental use of different physical and chemical Al forms, different routes of administration, and different target organs in relation to the magnitude, frequency, and duration of exposure. Wide variations in diet can result in Al intakes that are often higher than the World Health Organization provisional tolerable weekly intake (PTWI), which is based on studies with Al citrate. Comparing daily dietary Al exposures on the basis of “total Al”assumes that gastrointestinal bioavailability for all dietary Al forms is equivalent to that for Al citrate, an approach that requires validation. Current occupational exposure limits (OELs) for identical Al substances vary as much as 15-fold.
The toxicity of different Al forms depends in large measure on their physical behavior and relative solubility in water. The toxicity of soluble Al forms depends upon the delivered dose of Al+ 3 to target tissues. Trivalent Al reacts with water to produce bidentate superoxide coordination spheres [Al(O2)(H2O4)+ 2 and Al(H2O)6 + 3] that after complexation with O2•−, generate Al superoxides [Al(O2•)](H2O5)]+ 2. Semireduced AlO2• radicals deplete mitochondrial Fe and promote generation of H2O2, O2 • − and OH•. Thus, it is the Al+ 3-induced formation of oxygen radicals that accounts for the oxidative damage that leads to intrinsic apoptosis. In contrast, the toxicity of the insoluble Al oxides depends primarily on their behavior as particulates.
Aluminum has been held responsible for human morbidity and mortality, but there is no consistent and convincing evidence to associate the Al found in food and drinking water at the doses and chemical forms presently consumed by people living in North America and Western Europe with increased risk for Alzheimer\u27s disease (AD). Neither is there clear evidence to show use of Al-containing underarm antiperspirants or cosmetics increases the risk of AD or breast cancer. Metallic Al, its oxides, and common Al salts have not been shown to be either genotoxic or carcinogenic. Aluminum exposures during neonatal and pediatric parenteral nutrition (PN) can impair bone mineralization and delay neurological development. Adverse effects to vaccines with Al adjuvants have occurred; however, recent controlled trials found that the immunologic response to certain vaccines with Al adjuvants was no greater, and in some cases less than, that after identical vaccination without Al adjuvants.
The scientific literature on the adverse health effects of Al is extensive. Health risk assessments for Al must take into account individual co-factors (e.g., age, renal function, diet, gastric pH). Conclusions from the current review point to the need for refinement of the PTWI, reduction of Al contamination in PN solutions, justification for routine addition of Al to vaccines, and harmonization of OELs for Al substances
Physical Attractiveness, Altruism and Cooperation in an Ultimatum Game
Explaining cooperative tendencies through an evolutionary lens has been problematic for theorists. Traditional explanations derive from theories of reciprocity, biological markets, and more recently via partner choice and sexual selection. The sexual selection hypothesis has been tested within game-theoretic frameworks gaining empirical sup- port in explaining the evolution of altruism. Males have been found to be more altruistic towards attractive females. However, previous research has predominantly adopted a design where participants are not engaging with ‘real people’. Instead, participants make decisions when viewing images or hypothetical scenarios without visual cues. The present study aimed to investigate the sexual selection hypothesis using a face-to-face game theoretic framework. One hundred and thirty-eight participants played a 2-round ultimatum game with chocolate coins as the monetary incentive. We find, that physical attractiveness had no influence on generosity and cooperation when participants play a face-to-face ultimatum game. Instead, proposers were fair when allocating stakes, offering an average of half the endowment to responders. This study refutes the link between the sexual selection hypothesis and generosity when playing economic games with real people. Fairness appeared to drive generosity and cooperation
Myometrial contractility influences oxytocin receptor (OXTR) expression in term trophoblast cells obtained from the maternal surface of the human placenta
A model to explain specific cellular communications and cellular harmony:- a hypothesis of coupled cells and interactive coupling molecules
Skin Biopsy Techniques for the Internist
OBJECTIVE: To review three commonly performed skin biopsy procedures: shave, punch, and excision. DATA SOURCES: English-language articles identified through a MEDLINE search (1966 –1997) using the MeSH headings skin and biopsy, major dermatology and primary care textbooks, and cross-references. STUDY SELECTION: Articles that reviewed the indications, contraindications, choice of procedure, surgical technique, specimen handling, and wound care. DATA EXTRACTION: Information was manually extracted from all selected articles and texts; emphasis was placed on information relevant to internal medicine physicians who want to learn skin biopsy techniques. DATA SYNTHESIS: Shave biopsies require the least experience and time but are limited to superficial, nonpigmented lesions. Punch biopsies are simple to perform, have few complications, and if small, can heal without suturing. Closing the wound with unbraided nylon on a C-17 needle will enhance the cosmetic result but requires more expertise and time. Elliptical excisions are ideal for removing large or deep lesions, provide abundant material for many studies, and can be curative for a number of conditions, but require the greatest amount of time, expertise, and office resources. Elliptical excisions can be closed with unbraided nylon using a CE-3 or FS-3 needle in thick skin or a P-3 needle on the face. All specimens should be submitted in a labeled container with a brief clinical description and working diagnosis. CONCLUSIONS: Skin biopsies are an essential technique in the management of skin diseases and can enhance the dermatologic care rendered by internists
Monkeypox Virus Infection in Humans across 16 Countries - April-June 2022
Background: Before April 2022, monkeypox virus infection in humans was seldom reported outside African regions where it is endemic. Currently, cases are occurring worldwide. Transmission, risk factors, clinical presentation, and outcomes of infection are poorly defined. Methods: We formed an international collaborative group of clinicians who contributed to an international case series to describe the presentation, clinical course, and outcomes of polymerase-chain-reaction.confirmed monkeypox virus infections. Results: We report 528 infections diagnosed between April 27 and June 24, 2022, at 43 sites in 16 countries. Overall, 98% of the persons with infection were gay or bisexual men, 75% were White, and 41% had human immunodeficiency virus infection; the median age was 38 years. Transmission was suspected to have occurred through sexual activity in 95% of the persons with infection. In this case series, 95% of the persons presented with a rash (with 64% having ≤10 lesions), 73% had anogenital lesions, and 41% had mucosal lesions (with 54 having a single genital lesion). Common systemic features preceding the rash included fever (62%), lethargy (41%), myalgia (31%), and headache (27%); lymphadenopathy was also common (reported in 56%). Concomitant sexually transmitted infections were reported in 109 of 377 persons (29%) who were tested. Among the 23 persons with a clear exposure history, the median incubation period was 7 days (range, 3 to 20). Monkeypox virus DNA was detected in 29 of the 32 persons in whom seminal fluid was analyzed. Antiviral treatment was given to 5% of the persons overall, and 70 (13%) were hospitalized; the reasons for hospitalization were pain management, mostly for severe anorectal pain (21 persons); soft-tissue superinfection (18); pharyngitis limiting oral intake (5); eye lesions (2); acute kidney injury (2); myocarditis (2); and infection-control purposes (13). No deaths were reported. Conclusions: In this case series, monkeypox manifested with a variety of dermatologic and systemic clinical findings. The simultaneous identification of cases outside areas where monkeypox has traditionally been endemic highlights the need for rapid identification and diagnosis of cases to contain further community spread
CRF2 Signaling Is a Novel Regulator of Cellular Adhesion and Migration in Colorectal Cancer Cells
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