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1.
J Ophthalmol ; 2019: 6212745, 2019.
Article in English | MEDLINE | ID: mdl-31312530

ABSTRACT

[This corrects the article DOI: 10.1155/2016/3690140.].

2.
J Ophthalmol ; 2016: 3690140, 2016.
Article in English | MEDLINE | ID: mdl-26885380

ABSTRACT

Zeaxanthin is a nutritional carotenoid with a considerable amount of safety data based on regulatory studies, which form the basis of its safety evaluation. Subchronic OECD guideline studies with mice and rats receiving beadlet formulations of high purity synthetic zeaxanthin in the diet at dosages up to 1000 mg/kg body weight (bw)/day, and in dogs at over 400 mg/kg bw/day, produced no adverse effects or histopathological changes. In developmental toxicity studies, there was no evidence of fetal toxicity or teratogenicity in rats or rabbits at dosages up to 1000 or 400 mg/kg bw/day, respectively. Formulated zeaxanthin was not mutagenic or clastogenic in a series of in vitro and in vivo tests for genotoxicity. A 52-week chronic oral study in Cynomolgus monkeys at doses of 0.2 and 20 mg/kg bw/day, mainly designed to assess accumulation and effects in primate eyes, showed no adverse effects. In a rat two-generation study, the NOAEL was 150 mg/kg bw/day. In 2012, this dosage was used by EFSA (NDA Panel), in association with a 200-fold safety factor, to propose an Acceptable Daily Intake equivalent to 53 mg/day for a 70 kg adult. The requested use level of 2 mg/day was ratified by the EU Commission.

3.
Regul Toxicol Pharmacol ; 75: 5-19, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26713891

ABSTRACT

Synthetic astaxanthin has been extensively tested for safety. Genotoxicity studies including Ames and in vitro Micronucleus Tests show absence of genotoxic potential. Although a long-term mouse study showed no carcinogenicity potential, the rat carcinogenicity study with dietary dosages of 0 (control), 0 (placebo beadlet), 40, 200 and 1000 mg astaxanthin/kg bw/day showed an increased incidence of benign, hepatocellular adenoma in females only, at 200 mg/kg bw/day and above. There was no clear evidence of toxicity during the in-life phase. Discoloration of feces was observed and a reduction in body weight gain in all groups receiving beadlets, probably reflecting a nutritional influence. Blood sampling confirmed systemic exposure and some minor clinical chemistry differences in females at 200 and 1000 mg/kg bw/day. There was no effect on adjusted liver weight. Histopathological examination showed hepatic changes indicative of slight hepatotoxicity and hepatocyte regeneration in females at 200 and 1000 mg/kg bw/day, in addition to the adenoma. Taking into account this pathological background in the female rat, and a wide variety of other supporting information, it is concluded that the hepatocellular adenoma in female rats was secondary to hepatotoxicity and regeneration, and is most probably a species-specific phenomenon of doubtful human relevance.


Subject(s)
Adenoma, Liver Cell/chemically induced , Animals , Carcinogenicity Tests , Female , Male , Mice , Mutagenicity Tests , Rats , Sex Factors , Species Specificity , Xanthophylls/toxicity
4.
J Plast Reconstr Aesthet Surg ; 67(10): 1371-7, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24917373

ABSTRACT

BACKGROUND: Injury to the face can result in the loss of critical specialized structures (the eyelids, lips, ears and nose). Vascularized composite allotransplantation (VCA) allows the surgeon to replace exactly what has been lost. The success of the clinical face transplants suggests the possibility of transplanting specialized units of the face. In this study we explore the neurovascular anatomy and technical specifics for harvest of a functional composite eyelid subunit flap. METHODS: 12 fresh cadaver heads were studied, each yielding two flaps (N = 24). The facial (FA) and superficial temporal arteries (STA) were cannulated and injected with a gelatin/acrylic dye mixture. 6 cadaver heads were evaluated via high-resolution three-dimensional CT scans with contrast. RESULTS: The dye injected into the STA uniformly stained the tissue of the eyelid/periorbital subunit. Injection into the FA resulted in staining of the skin and soft tissues in the medial canthal region and superior eyelid skin in 66% of specimens. CT scan studies confirm our findings with injection into the STA resulting in contrast infiltration of the palpebral arterial arcades in all cases. Injection of the FA resulted in contrast infiltration of the palpebral arterial arcades in 2 of 3 cases. CONCLUSIONS: Based this study, a periorbital flap can be based on the STA. Motor innervation of the flap is via the zygomatic and buccal branches of the facial nerve with sensory innervation via the infraorbital, supraorbital and supratrochlear nerves. FA could be used, but its ability to perfuse the entire flap was inconsistent.


Subject(s)
Composite Tissue Allografts , Facial Transplantation/methods , Tissue and Organ Harvesting/methods , Vascularized Composite Allotransplantation/methods , Composite Tissue Allografts/blood supply , Composite Tissue Allografts/innervation , Dissection/methods , Humans , Temporal Arteries
5.
Food Chem Toxicol ; 47(9): 2170-82, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19505523

ABSTRACT

trans-Resveratrol is a naturally occurring polyphenolic compound found in a variety of foods, but predominantly in grapes. Safety studies were conducted on high-purity trans-resveratrol (Resvida), including skin and eye irritation, dermal sensitization, subchronic and reproductive toxicity, genotoxicity, and absorption, metabolism and excretion. Resvida was non-irritating to skin and eyes and non-sensitizing. It was non-mutagenic in a bacterial reverse mutation assay in Salmonella typhimurium and Escherichia coli, but exhibited clastogenic activity in a chromosomal aberration test in human lymphocytes. However, in an in vivo bone marrow micronucleus test in rats, Resvida was non-genotoxic. In a 28-day study, Resvida caused no adverse effects in rats at 50, 150 and 500 mg/kg bw/day. Similarly, in a 90-day study, Resvida did not cause any adverse effects in rats at up to 700 mg/kg bw/day; the highest dose tested. Resvida did not induce any adverse reproductive effects in an embryo-fetal toxicity study in rats at a dose of 750 mg/kg bw/day. Also, in vitro and in vivo absorption, metabolism, and excretion studies in Caco-2 cells, rat primary hepatocytes and male and female rats (in vivo) show that Resvida is readily absorbed, metabolized and excreted. These studies provide evidence that Resvida is well tolerated and non-toxic.


Subject(s)
Antioxidants/toxicity , Stilbenes/toxicity , Toxicity Tests , Animals , Antioxidants/pharmacokinetics , Chromosome Aberrations , Embryo, Mammalian/drug effects , Embryo, Mammalian/embryology , Embryonic Development/drug effects , Eye/drug effects , Eye/pathology , Female , Humans , Local Lymph Node Assay , Male , Micronucleus Tests , Pregnancy , Rabbits , Rats , Rats, Sprague-Dawley , Rats, Wistar , Reproduction/drug effects , Resveratrol , Salmonella typhimurium/drug effects , Salmonella typhimurium/genetics , Skin Irritancy Tests , Stilbenes/pharmacokinetics
6.
J Burn Care Res ; 30(2): 243-8, 2009.
Article in English | MEDLINE | ID: mdl-19165108

ABSTRACT

Severe burn injury results in a systemic inflammatory response that leads to increased capillary permeability and fluid leak into the interstitium. This global systemic capillary leak can be attributed, at least in part, to inflammatory mediators produced as a result of cellular injury. Plasma exchange has been used in the management of a number of illnesses with a significant inflammatory component, and, therefore, may have a role in the early management of burn injury. The purpose of this study was to review our institutional experience using plasma exchange in the management of severe burn injury. We performed a retrospective review of all patients receiving plasma exchange at our burn center between 2001 and 2005. Data collected included the following: burn size, presence of inhalation injury, resuscitation fluid received, urine output, lactate levels, base deficit levels, and hematocrit before and after the exchange procedure. A total of 37 patients underwent plasma exchange during the 5-year study period and seven patients underwent two plasma exchange treatments. Average TBSA burned was 48.6% (range 18-82) and 73% of patients sustained an inhalation injury. After plasma exchange, hourly fluid volume received significantly decreased (P < .05) and base deficit, lactate, and hematocrit levels significantly improved. Plasma exchange in the early resuscitation period was associated with decreased fluid administration, as well as increased urine output in the period during and immediately after the procedure. These data suggest that plasma exchange may provide a useful tool in the management of severe burn injury.


Subject(s)
Burns/therapy , Plasma Exchange , Adult , Body Surface Area , Female , Humans , Male , Retrospective Studies , Treatment Outcome
7.
Food Chem Toxicol ; 44(1): 56-80, 2006 Jan.
Article in English | MEDLINE | ID: mdl-16213646

ABSTRACT

Genistein is a phytoestrogen that occurs naturally in the diet, especially in soy based foods. There is wide spread interest in phytoestrogens as chemopreventive agents for a variety of diseases and cancers based on epidemiologic evidence. Although soy, and its constituents such as genistein, have been consumed at high levels in several Asian populations without apparent adverse effects, concern has been raised about potential adverse effects due to the estrogenic and other activities. Safety studies with genistein were conducted in the Wistar rat including two acute studies, two subchronic (4 weeks and 13 weeks) and a chronic 52-week dietary admix study. In the acute studies, genistein had a low order of toxicity. In the three repeated dose safety studies at doses up to 500 mg/kg/day, genistein was well tolerated. In all of the studies, decreased food consumption and body weight gain were observed at 500 mg/kg/day. The main hematological findings were decreased red blood cell parameters at 500 mg/kg/day with a compensatory increase in reticulocytes. For clinical chemistry, with the exception of a slight increase in gamma glutamyl transferase in male and female rats at the high dose, there were a number of other minor changes considered not toxicologically significant. At necropsy, there were relatively few macroscopic changes; in the 52-week study, dilation of the uterus with fluid at the high dose and cysts of the ovaries in treated animals were observed. Organ weight changes in male rats at the high dose of 500 mg/kg/day included increased kidney, spleen, adrenal and testes weights and for females included, increased liver, kidney, spleen, ovary and uterus weights. After 4 and 13 weeks of treatment with genistein, there were no treatment related histopathologic findings. After 26 and 52 weeks of treatment, histological changes were seen in the female reproductive organs (ovaries and uterus), and in males (epididymides and prostate), and bone, kidneys, heart, liver and spleen in both sexes. After 52 weeks of treatment of males, vacuolation of the epididymal epithelium at 500 mg/kg/day and inflammation of the prostate were recorded at a higher incidence at 50 and 500 mg/kg/day. In females, cytological changes in the uterus, squamous metaplasia at 50 and 500 mg/kg/day and hyperplasia at 500 mg/kg/day were observed. Furthermore, hydrometra of the uterus and findings in the vagina consisting of anestric or diestrus vaginal mucosa with vaginal mucification, hyperplastic epithelium and multifocal cystic degeneration were noted at 500 mg/kg/day. Atrophy of the ovaries increased in severity in animals at 50 and 500 mg/kg/day. Osteopetrosis (hyperostosis) was observed in male and female rats at 50 and 500 mg/kg/day along with a compensatory increase in extramedullary hemopoiesis in the spleen; females were more affected than males. Hepatocellular hypertrophy and minimal bile duct proliferation were recorded at a higher incidence in animals at 500 mg/kg/day. It is concluded that almost all of the treatment related findings in these studies are related to the estrogenic properties of genistein as a phytoestrogen and would be expected to occur with a compound with estrogenic activity. The hormonally related changes were considered to be functional in nature and thus not adverse effects. Most of the findings in these studies were limited to the high dose of 500 mg/kg/day and were reversible. The few findings observed at 50 mg/kg/day were relatively minor and in view of the functional (hormonally mediated) nature of the effects, were considered not adverse effects. The increased incidence of minimal bile duct proliferation and slightly increased gamma glutamyl transferase are indicative of a mild hepatic effect at the high dose of 500 mg/kg/day. The no observed adverse effect level (NOAEL) of genistein is considered to be 50 mg/kg/day based on the presence of mild hepatic effects at the high dose of 500 mg/kg/day. The no observed effect level (NOEL) is considered to be 5 mg/kg/day based on the hormonally induced functional changes at higher doses.


Subject(s)
Anticarcinogenic Agents/toxicity , Genistein/toxicity , Phytoestrogens/toxicity , Administration, Oral , Animals , Anticarcinogenic Agents/classification , Anticarcinogenic Agents/pharmacokinetics , Dose-Response Relationship, Drug , Erythrocytes/drug effects , Erythrocytes/pathology , Female , Genistein/classification , Genistein/pharmacokinetics , Male , No-Observed-Adverse-Effect Level , Organ Size/drug effects , Phytoestrogens/classification , Phytoestrogens/pharmacokinetics , Rats , Rats, Wistar , Recovery of Function , gamma-Glutamyltransferase/blood
8.
Endocr Pathol ; 3(3): 116-128, 1992 Sep.
Article in English | MEDLINE | ID: mdl-32138394

ABSTRACT

Thirty-two adrenocortical neoplasms in children and adolescents were evaluated for prognostic factors including clinical and morphological parameters and DNA ploidy. The patients were segregated into two groups according to clinical outcome: group A, represented by patients with clinically benign neoplasms (n = 15), and group B, patients with clinically malignant tumors as evidenced by local recurrence, metastases, or fatal outcome (n = 17). Clinical and morphological parameters in these two groups were evaluated using appropriate statistical methods. Parameters with a significant predictive value in terms of prognosis were age [p = .04], tumor size (p = .0003), median tumor weight (p = .0001), mitotic count (p = 0.04), and 25% tumor necrosis or more (p = .03). Twenty-three cases were studied for DNA ploidy: 10 cases by image analysis and 13 by both image analysis and flow cytometry. By ploidy analysis, 17 of 23 cases-12 of 14 in group A and 5 of 9 in group B-were found to be aneuploid. Multiple aneuploid peaks were found in 5 of 23 cases-4 of 14 cases in group A and 1 of 9 cases in group B. In tumors studied by both image analysis and flow cytometry, there was no discrepancy between results of ploidy analysis. There was no statistically significant association demonstrated between clinical outcome and DNA ploidy pattern. DNA ploidy heterogeneity, characterized by multiple aneuploid populations of cells, was also detected in both benign and malignant neoplasms. Based on our results, aneuploidy is relatively frequent in pediatrie adrenocortical tumors and does not appear to have predictive value for biological behavior.

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