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1.
Int J Toxicol ; 43(1): 19-26, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37787596

RESUMO

D-PLEX100 (D-PLEX) is a novel product candidate made of a polymer-lipid-based matrix (PLEX platform) which contains doxycycline that is being released at a constant rate for 30 days. D-PLEX was developed to prevent surgical site infections, which are a major global health challenge. Previous studies have shown its safety in adult humans, adult swine, and adult rabbits. The aim of this study was to assess the toxicity and safety of D-PLEX also in juvenile animals to support future clinical trials in pediatric patients. Yucatan miniature swine were selected as a model, primarily due to their relatively larger mass. D-PLEX or placebo (formulation without doxycycline) was administered locally to abdominal incisions, and the animal's safety parameters were followed for 9 months and compared to sham-control swine. There was no evidence of any systemic safety concern or local toxicity at the incision site in D-PLEX-treated animals. D-PLEX was detected after 1 month and was fully resorbed at the 3-month time point. The surgical incision sites were fully healed at the 6-month time point in all D-PLEX-treated animals. Toxicokinetic (TK) assessments revealed that doxycycline exhibited low Cmax and therefore minimal systemic exposure following a single dose of local administration. This study provides evidence for the safety of D-PLEX and PLEX-based formulation in juvenile miniature swine and supports its further testing in clinical pediatric population. In addition, it can be used as a reference for future preclinical studies aiming to evaluate the safety of other PLEX-based product candidates for the pediatric population.


Assuntos
Doxiciclina , Porco Miniatura , Animais , Doxiciclina/efeitos adversos , Toxicocinética
2.
Pharmaceutics ; 15(12)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38140085

RESUMO

Prostate cancer is a significant health concern for men, emphasizing the need for effective treatment strategies. Dose-escalated external beam radiotherapy shows promise in improving outcomes but presents challenges due to radiation effects on nearby structures, such as the rectum. Innovative techniques, including rectal spacers, have emerged to mitigate these effects. This study comprehensively assessed tissue responses following the implantation of the Bioprotect biodegradable fillable balloon as a rectal spacer in a rat model. Evaluation occurred at multiple time points (4, 26, and 52 weeks) post-implantation. Results revealed localized tissue responses consistent with the expected reaction to biodegradable materials, characterized by mild to moderate fibrotic reactions and encapsulation, underscoring the safety and biocompatibility of the balloon. Importantly, no other adverse events occurred, and the animals remained healthy throughout the study. These findings support its potential clinical utility in radiotherapy treatments to enhance patient outcomes and minimize long-term implant-related complications, serving as a benchmark for future similar studies and offering valuable insights for researchers in the field. In conclusion, the findings from this study highlight the safety, biocompatibility, and potential clinical applicability of the Bioprotect biodegradable fillable balloon as a promising rectal spacer in mitigating radiation-induced complications during prostate cancer radiotherapy.

3.
Oral Dis ; 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37983887

RESUMO

OBJECTIVE: The familial type of oral lichen planus (OLP) is rare, with a paucity of data regarding its clinical significance. Our objective was to characterize patients with familial OLP. METHODS: Families with at least two members diagnosed with OLP were included. Clinical and demographic data and medical history were recorded. RESULTS: Twenty families, 19 Jewish and 1 Arab, were identified. Of the Jewish families, 57.8% were non-Ashkenazi, originating mainly from central Asia. Of those with OLP there were 14 males and 23 females with an average age of 49.1. Dyslipidemia, cardiovascular, and thyroid disorders (27.7%, 22.2%, and 16.6%, respectively) were the most common comorbidities. Five patients from five distinct families had oral cancer, two with second primary. CONCLUSIONS: To the best of our knowledge, this is the largest study describing familial OLP. The predominant and common ethnicity of the families with multiple members diagnosed with OLP may imply an ethnic tendency. The higher tendency of hypothyroidism and the high percentage of OSCC among familial OLP patients might be connected to familial OLP and the latter suggests that this population is predisposed to malignant transformation. Thus, this group should be considered as a high-risk group.

4.
Food Chem Toxicol ; 176: 113734, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36935076

RESUMO

In this combined chronic toxicity/carcinogenicity study of gardenia blue as a natural food color additive, Sprague Dawley rats were administered 0.5%, 2.5%, or 5.0% gardenia blue via the feed or carrier diet (0.0% gardenia blue) for 12 (chronic toxicity cohort) or 24 (carcinogenicity cohort) months. No abnormal clinical, ophthalmological, neurotoxicity or clinical pathology changes were attributed to treatment, and there was no increase in mortality due to gardenia blue exposure. The only treatment-related change was grossly observed blue discoloration of the stomach, intestines, and mesenteric lymph nodes as well as reversible dark discoloration of the kidneys all without associated histopathology. The no-observed-adverse-effect level (NOAEL) for gardenia blue exposure via the diet for one or two years was determined to be 5.0% (2175.3 mg/kg body weight/day in male rats and 3075.4 mg/kg body weight/day in female rats).


Assuntos
Gardenia , Ratos , Feminino , Masculino , Animais , Ratos Sprague-Dawley , Dieta , Rim , Peso Corporal
5.
Regul Toxicol Pharmacol ; 140: 105343, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36773715

RESUMO

alpha-Glycosyl isoquercitrin (AGIQ) is a flavonoid that possesses antioxidant and tumor suppressive capabilities and is marketed as a food additive in Japan. The aim of this study was to assess the potential for oral chronic toxicity and carcinogenicity of AGIQ in male and female Sprague Dawley rats following up to 5.0% dietary exposure. In the chronic toxicity study, rats were exposed to AGIQ or vehicle for one year with a 6-month interim termination point; for the carcinogenicity study, rats were treated for 24 months. No signs of AGIQ-related toxicity clinically or histologically were observed for up to one year except for yellow discoloration of bone. In the carcinogenicity study, a statistically significant increase in the incidence of malignant glioma of the brain or spinal cord was observed in female rats exposed to 5.0% AGIQ compared to those exposed to control feed. A Scientific Advisory Panel of experienced neuropathologists reviewed the gliomas (routine stains and glial cell markers) and concluded that the gliomas were a rare, spontaneous, rat-specific neoplasm: malignant microglial tumor. The lesions could not definitively be attributed to AGIQ exposure and have limited implications with respect to predicting human cancer risk.


Assuntos
Glioma , Quercetina , Ratos , Masculino , Feminino , Humanos , Animais , Ratos Sprague-Dawley , Quercetina/toxicidade , Antioxidantes , Glioma/induzido quimicamente
6.
J Toxicol Pathol ; 36(1): 11-19, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36683728

RESUMO

Laser resurfacing may be accompanied by unwanted side effects. The micro coring technology, designed to remove small skin columns, was developed to avoid the thermal injury associated with lasers. However, very limited data are available on its pre-clinical efficacy and safety. The novel robotic, fractional micro-coring device, AimeTM, was tested on four pigs, each treated in 12 sites, at 6 time-points, over the course of 28 days. Macroscopic and microscopic evaluation was performed at each of the 6 time-points during the 28-day follow-up. Macroscopically, treatment resulted in erythema and mild edema that quickly resolved. Microscopically, there was progressive re-coverage of the tested sites with complete, well differentiated, newly formed epidermis, associated with efficient elimination of the underlying excised dermis, which was replaced by maturing fibroplasia. Some of the sites demonstrated complete healing already after 7 days. No significant adverse events were noted with the use of the device. The use of the micro-coring device AimeTM in a porcine model for skin fractional micro-excision and resurfacing was effective and safe. The comprehensive gradual healing process shown in this study with detailed histopathological images can also serve as a basis for future pre-clinical studies of fractional ablative devices.

7.
Int J Toxicol ; 42(4): 334-344, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36634266

RESUMO

Thyrotropin-releasing hormone (TRH) and TRH-like peptides carry a therapeutic potential for neurological conditions. Nanoparticles (NP) made of the biodegradable polymer, Poly(Sebacic Anhydride) (PSA), have been developed to carry TRH, intended for intranasal administration to patients. There is limited information on the safety of biodegradable polymers when given intranasally, and therefore, we have performed two preclinical safety and toxicity studies in cynomolgus monkeys and rats using TRH-PSA nanoparticles. The rats and monkeys were dosed intranasally for 42 days or 28 days, respectively, and several animals were followed for additional 14 days. Animals received either placebo, vehicle (PSA), or different concentrations of TRH-PSA. No systemic adverse effects were seen. Changes in T3 or T4 concentrations were observed in some TRH-PSA-treated animals, which did not have clinical or microscopic correlates. No effect was seen on TSH or prolactin concentrations. In the monkey study, microscopic changes in the nasal turbinates were observed, which were attributed to incidental mechanical trauma caused during administration. Taken together, the TRH-loaded PSA NPs have proven to be safe, with no local or systemic adverse effects attributed to the drug loaded nanoparticles. These findings provide additional support to the growing evidence of the safety of peptide-loaded NPs for intranasal delivery and pave the way for future clinical trials in humans.


Assuntos
Nanopartículas , Hormônio Liberador de Tireotropina , Hormônio Liberador de Tireotropina/administração & dosagem , Animais , Ratos , Macaca fascicularis , Administração Intranasal , Masculino , Feminino
8.
Photodermatol Photoimmunol Photomed ; 39(3): 256-262, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36052749

RESUMO

BACKGROUND: Ultraviolet (UV) A1 phototherapy is considered a beneficial treatment for various inflammatory, sclerotic, malignant, and other skin conditions. However, the available data regarding its efficacy for different indications, the potential side effects, and the recommended treatment protocols are sparse. OBJECTIVES: To assess the efficacy of UVA1 phototherapy and identify correlation between different indications and treatment protocols to response rates. METHODS: We performed a retrospective study of a cohort of 335 patients treated with UVA1 phototherapy at the Department of Dermatology at Hadassah Medical Center, Jerusalem, Israel, between 2008 and 2018. RESULTS: The study population included 163 patients with inflammatory diseases (mainly atopic dermatitis and other types of eczema), 67 patients with sclerotic diseases (morphea and graft versus host disease), nine patients with neoplastic diseases (cutaneous T cell lymphoma), and 188 patients with other cutaneous disorders. Response rates ranged between 85% and 89% across indications, without differences in response rates among the indication groups (p = .941). In a multivariant logistic regression model, increased number of treatments and higher maximal dosages were associated with response to treatment (p < .001). Using ROC analysis, a cut-off of 8 UVA1 phototherapy treatments was chosen as predictive for beneficial response (86.4% sensitivity, 78% specificity). A cut-off of 40 J/cm2 was chosen as an optimal maximal dosage for differentiating between responders and non-responders (51.1% sensitivity, 83.1% specificity). CONCLUSIONS: UVA1 phototherapy is an effective treatment for a variety of skin conditions. In most patients, at least eight treatments of a medium-high dosage are required for clinical response.


Assuntos
Esclerodermia Localizada , Neoplasias Cutâneas , Terapia Ultravioleta , Humanos , Terapia Ultravioleta/efeitos adversos , Estudos Retrospectivos , Centros de Atenção Terciária , Esclerodermia Localizada/etiologia , Esclerodermia Localizada/patologia , Resultado do Tratamento , Neoplasias Cutâneas/etiologia , Fototerapia
9.
Toxicol Pathol ; 50(2): 211-217, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34965791

RESUMO

One of the challenging aspects of minimal invasive surgery (MIS) is intracorporal suturing, which can be significantly time-consuming. Therefore, there is a rising need for devices that can facilitate the suturing procedure in MIS. Su2ura Approximation Device (Su2ura Approximation) is a novel device developed to utilize the insertion of anchors threaded with stitches to allow a single action placement of a suture. The objective of this study was to evaluate the long-term safety and tissue approximation of Su2ura Approximation in comparison to Endo Stitch + Surgidac sutures in female domestic pigs. All incision sites were successfully closed by both methods. Firm consolidation within and around the incision site was noted in several animals in both treatment groups, which corresponded histopathologically to islands of ectopic cartilage or bone spicules within the fibrotic scar. These changes reflect heterotopic ossification that is commonly seen in the healing of abdominal operation sites in pigs. No other abnormal findings were observed throughout the study period. In conclusion, the use of Su2ura Approximation under the present experimental conditions revealed no safety concerns.


Assuntos
Técnicas de Sutura , Suturas , Animais , Feminino , Suínos
10.
J Toxicol Pathol ; 34(3): 181-211, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34290474

RESUMO

Herbal products have been in use for many years, but they are becoming more and more popular in recent years, and they are currently in widespread use throughout the world. In this review article we describe the histopathologic findings found after exposure to 12 dietary herbals in studies conducted in rodent model systems. Clear or some evidence for carcinogenic activity was seen with 6 herbals, with the liver being the most common organ affected. The intestine was affected by two herbals (aloe vera nondecolorized extract and senna), three had no clear evidence for carcinogenic activity and one was cardiotoxic (Ephedrine and Ephedra in combination with caffeine). Information from these studies can help to better understand potential target organs for further evaluation from exposure to various herbal products.

12.
Toxicol Pathol ; 49(5): 1062-1076, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33576321

RESUMO

Oral cancer is the seventh most common malignancy worldwide, and lifestyle factors participate in its development. Rodent studies can help identify substances that contribute to its development and provide information on the early stages of carcinogenicity. The National Toxicology Program (NTP) has conducted more than 500 short-term and 2-year toxicology and carcinogenicity studies in rodents, and some of the tested compounds resulted in oral cancer. Our goal was to review the NTP carcinogenic studies to describe those chemicals that have oral carcinogenic outcome in rodents. For this project, we reviewed the results from all NTP carcinogenicity studies and a board-certified veterinary pathologist reviewed the slides from all neoplasms in the oral cavity that were considered treatment related. We have identified 26 chemicals with an adverse effect in the oral cavity. Fourteen chemicals demonstrated clear evidence of carcinogenicity in the oral cavity. We provide information on the carcinogenic findings in rodents together with a detailed description of the morphologic aspects of the oral cancers and speculate that the carcinogenic effects can be induced by different pathological modes of action. The findings reviewed here provide indicators for potential oral carcinogenesis processes in rodent models, which can be further investigated in future mechanistic studies.


Assuntos
Neoplasias de Células Escamosas , Neoplasias , Animais , Testes de Carcinogenicidade , Carcinógenos/toxicidade , Humanos , Roedores
15.
Toxicol Pathol ; 48(5): 677-685, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32525456

RESUMO

Surgical site infections (SSIs) are a common surgical-related complication. To avoid these complications, a new biodegradable polymer-lipid encapsulation matrix that provides controlled release of doxycycline (doxycycline/polymer-lipid encapsulation matrix [D-PLEX]) has been developed. The aim of this comprehensive study was to evaluate the potential safety of D-PLEX100 in abdominal surgical site. D-PLEX100 was administered into incisions of abdominal surgical site in Yucatan miniature swine, which were followed for up to 6 months and compared to sham-control swine. The D-PLEX100 mass did not migrate from the incisional site, and there was no evidence for systemic toxicity or other safety concerns. Surgical incision sites, including the peritoneal surface, were fully healed at 6 months in all animals. Most of the D-PLEX100 mass was absorbed during the first 3 months, and by 6 months, D-PLEX100 was fully absorbed. Toxicokinetic evaluation revealed that doxycycline concentrations were evident at 30 minutes and persisted to 8 days (71 mg/kg) or at least 15 days (284 mg/kg) and were no longer present in plasma by day 29. This study supports the safety of D-PLEX100 and its favorable degradability profile. A clinical study is being performed to assess the safety and the efficacy of D-PLEX100 to prevent human abdominal SSIs.


Assuntos
Doxiciclina/administração & dosagem , Sistemas de Liberação de Medicamentos , Modelos Animais , Infecção da Ferida Cirúrgica , Animais , Humanos , Suínos , Porco Miniatura
16.
Toxicol Pathol ; 48(5): 686-693, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32431233

RESUMO

Information on the safety of energy-based dermatological surgical devices in domestic pigs, and fractional radiofrequency (RF) devices in particular, is very limited. The aim of this study was to evaluate in a GLP-compliant study in domestic pigs the local reaction and performance of a novel fractional RF device. Five female domestic pigs were subjected to fractional RF pulses, using different energy and pulse durations and depth of penetration of the pulses. The animals were evaluated clinically and histologically at different time points (days 0, 1, 3, 7, and 14) postenergy exposure. There were no microscopic or macroscopic local adverse effects in any tested power settings, and there was time-related progressive healing, reaching complete macroscopic and microscopic healing by 7 days postapplication. As expected, there was power-related progressive increase in the incidence of ablation (destruction of skin tissue by vaporization) and coagulative necrosis of the dermis from low to high power setting. This comprehensive study, using multiple power settings (both ablative and coagulative) and several time points, will be of benefit for future studies evaluating new fractional RF devices.


Assuntos
Ablação por Radiofrequência , Pele/patologia , Animais , Feminino , Terapia a Laser , Modelos Animais , Sus scrofa , Suínos
18.
Toxicol Pathol ; 47(4): 483-493, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30898059

RESUMO

Self-adhesive meshes are being developed to avoid complications due to traumatic fixation methods. LifeMesh™ is a novel self-adhesive mesh with a biodegradable gelatin adhesive layer developed for hernia repair. The aim of this study was to assess the safety and biodegradability of LifeMesh in Sprague-Dawley (SD) rats for 6 weeks, in comparison to a bare polypropylene (BPP) mesh fixed with sutures. LifeMesh was tolerated well and its implantation did not result in any adverse local reaction, and its adhesive layer was substantially degraded after 4 weeks. Histopathological examination revealed that the presence of the adhesive contributed to a uniform thickness of the granulation tissue surrounding the mesh, in contrast to a nonuniform granulation tissue with BPP. Nonuniform granulation tissue suggests that there will be poorer integration of the mesh to the abdominal wall. The use of LifeMesh also resulted in less adhesions of internal organs with a smaller surface area of involvement. These findings lend support to the potential benefit of LifeMesh for hernia repair in humans and expand the available information on the typical histopathological findings expected with biodegradable implants in the peritoneal cavity of SD rats.


Assuntos
Implantes Absorvíveis , Telas Cirúrgicas/efeitos adversos , Adesivos Teciduais/efeitos adversos , Parede Abdominal/patologia , Parede Abdominal/cirurgia , Animais , Masculino , Polipropilenos/efeitos adversos , Ratos Sprague-Dawley , Suturas , Aderências Teciduais/etiologia
19.
Toxicol Pathol ; 46(6): 693-705, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30009686

RESUMO

Mastic gum extracts are widely used as herbal remedies and are being tested for several clinical indications. Nevertheless, information on their safety is limited. RPh201 is an extract of the mastic gum, formulated and stabilized in a proprietary method, which is being developed as a novel drug candidate for neurological indications. The aim of this study was to assess the systemic toxic potential of RPh201, administered twice weekly by subcutaneous injections to minipigs, after 39 weeks of administration followed by a recovery period of 6 weeks. No clinical or dose-related signs were observed, but treatment-related findings were seen at the injection sites of the high-dose animals, composed of abscesses, chronic inflammation, and subcutaneous fibrosis. Abscesses >30 mm in size, graded as marked severity, were confined to the high-dose group and were considered as adverse. Minimal-slight subcutaneous and lymph nodes abscesses seen in control, low, and intermediate doses, related to the vehicle (cottonseed oil), were not considered as adverse. Additionally, minimal-to-slight cystic spaces or vacuolation related to the vehicle were observed in the skin, lymph nodes, kidney, and lungs. These findings were considered not to be adverse. The no-observed-adverse-effect level was considered to be 12.5 mg/kg/occasion.


Assuntos
Reação no Local da Injeção/etiologia , Resina Mástique/química , Animais , Relação Dose-Resposta a Droga , Feminino , Hemoglobinas/análise , Reação no Local da Injeção/patologia , Injeções Subcutâneas , Contagem de Leucócitos , Masculino , Neutrófilos/citologia , Nível de Efeito Adverso não Observado , Tamanho do Órgão/efeitos dos fármacos , Suínos , Porco Miniatura , Testes de Toxicidade , Toxicocinética
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