Clinico-pathological evaluation of tumor budding in the oncological progression of colorectal cancer. / Evaluación clínico-patológica del tumorbudding en la progresión oncológica del cáncer colorrectal.

INTRODUCTION: Tumor budding (TB), defined as the presence of individual neoplastic cells or isolated groups of up to 4 cells at the front of tumor invasion, has become an adverse prognostic marker in colorectal cancer (CRC) in recent decades. The prognostic impact of TB in CRC remains not clearly defined and histological methods for its evaluation vary depending on the center. The objective of this study is to investigate the association between TB and CRC, in terms of oncological evolution and pathological stage. METHODS: A retrospective observational study was conducted, including patients undergoing curative oncological surgery for CRC between January 2017 and December 2022. The effects of TB on disease-free survival (DFS) and overall survival (OS) were evaluated according to the Kaplan-Meier curves. RESULTS: In 78 cases TB was described in the pathology report. TB was present in 56 patients (71.8%), divided into the following categories: low grade in 22 (39.3%), intermediate grade in 17 (30.4%) and high grade in 17 (30.4%). The proportion of patients who presented lymph node metastases, lympho-vascular and perineural invasion was significantly higher in patients with TB (26.8% vs 0%, P=.008; 41.1% vs 4.5%, P=.002; 16.1% vs 0% P=.054; respectively). DFS was 86.3% in low-grade TB, 75.3% in intermediate-grade TB, and 70.3% in high-grade TB. Cases with intermediate and high grade were associated with a shorter OS compared to the low grade group (93.7% and 75.4% vs 100% P=.012, respectively). CONCLUSION: These results suggest that TB expression may be a useful risk factor as a prognostic factor for the detection of lymph node metastasis, local recurrence, and distant metastasis in CRC.

Enfermedad de Paget perianal: un trastorno raro que enmascara un carcinoma anorrectal subyacente / Perianal Paget's disease: A rare disorder masking an underlying anorectal carcinoma

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Absceso hepático por Eikenella corrodens / Liver abscess by Eikenella corrodens

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A soft-surgery approach to minimize hearing damage caused by the insertion of a cochlear implant electrode: a guinea pig animal model.

OBJECTIVE: A "soft surgery" technique was applied, using various types of specifically designed dummy electrodes, to mimic cochlear implantation in a guinea pig model, and the degree of hearing-preservation/cochlear damage was assessed. METHODS: Tricolor guinea pigs were divided into 3 groups: group A were implanted with electrodes without any contacts or wires (soft electrode), group B were implanted with electrodes having a metallic wire inside (stiff electrode), and group C underwent a cochleostomy procedure without implantation. Compound action potentials, in the range of 4 to 32 kHz, were used to assess electrophysiologic changes in the hearing function presurgery and postsurgery. Data were collected before surgery, at times t = 0 (immediately after surgery) and at 3, 7, 14, and 30 days. RESULTS: At low frequencies (4-8 kHz), an immediate elevation of hearing threshold was observed in all 3 groups. Higher threshold shifts were more consistent for group B implanted with a stiff electrode, in comparison to the other 2 groups. Animals from group C presented a recovery from hearing loss, starting 3 days after surgery. At high frequencies (16-32 kHz), the elevation of hearing threshold was higher, as compared with the data from the low frequencies. Group C animals presented oscillatory threshold shifts twice, and the recovery to normal threshold values occurred approximately at t = 14 days. CONCLUSION: The data suggest that cochleostomy is minimally harmful to the inner ear and that a soft electrode might better preserve the inner ear integrity than a rigid electrode.

A new oral otoprotective agent. Part 1: Electrophysiology data from protection against noise-induced hearing loss.

BACKGROUND: Data from animal studies show that antioxidants can compensate against noise-induced stress and sensory hair cell death. The aim of this study was to evaluate the otoprotection efficacy of various versions of orally administered Acuval 400 against noise damage in a rat animal model. MATERIAL/METHODS: Fifty-five Sprague Dawley rats were divided into 4 groups: A) noise-exposed animals; B) animals exposed to noise and treated with the Acuval; C) animals exposed to noise and treated with a combination of Coenzyme Q10 and Acuval; D) animals treated only with Acuval and Coenzyme Q10 and with no exposure to noise. All solutions were administered orally 5 times: 24 and 2 hrs prior to noise exposure, and then daily for 3 days. The auditory function was assessed by measuring auditory brainstem responses (ABR) in the range from 2 to 32 kHz at times =1, 7, 14 and 21 days after noise exposure. RESULTS: At low frequencies (click and 4 kHz) animals from both A and B groups showed significant threshold shifts in the majority of the tested frequencies and tested times. For the same frequencies, animals from group C presented threshold levels similar to those from group D. At frequencies ≥ 8 kHz the protective performance of the 2 Acuval groups is more clearly distinguished from the noise group A. At 32 kHz the 2 Acuval groups perform equally well in terms of otoprotection. Animals in Group D did not show any significant differences in the hearing threshold during the experiment. CONCLUSIONS: The data of this study suggest that a solution containing Coenzyme Q10 and Acuval 400, administered orally, protects from noise-induced hearing loss.

Dose-dependent protection on cisplatin-induced ototoxicity - an electrophysiological study on the effect of three antioxidants in the Sprague-Dawley rat animal model.

BACKGROUND: Sprague-Dawley rats were used as an acute cisplatin ototoxicity model to compare the chemo-protective efficacy of 2 sulphur-containing antioxidants (D-methionine, N-L-acetylcysteine) and 1 seleno-organic compound (ebselen). Each putative chemo-protective agent was tested at 3 different dosages in order to assess the influence of dose on auditory preservation. MATERIAL/METHODS: A total of 40 Sprague-Dawley albino male rats were used in the study. Animals were divided into 10 groups, 3 groups of different doses for each protective agent and a cisplatin-treated control group. The animals were weight-matched before drug exposure to ensure similar weights in all groups. Auditory function was assessed with auditory brainstem responses and distortion product otoacoustic emissions at time zero and at 96 hours post-treatment. RESULTS: At the post-treatment follow-up no significant threshold change at 8 kHz was found in the D-Met- and NAC-treated groups. All ebselen-treated animals presented significant threshold elevations. At 12 and 16 kHz, only the groups treated with 300, 450 mg/kg of D-Met and 475 mg/kg of NAC presented thresholds comparable to the pre-treatment ABR data. The ebselen-treated animals presented significant threshold shifts and showed the highest threshold elevations. The DPOAE data analysis showed that only the animals from the 350 mg/kg D-met group presented lack of statistical differences between the pre and post recordings. CONCLUSIONS: Considering the outcome from the ABR and DPOAE analyses together, only the 350 mg/kg D-met group presented a complete auditory preservation against the 14 mg/kg cisplatin administered i.v. Data from ebselen pre-treated Sprague-Dawley albino male rats demonstrate that ebselen dosages up to 12 mg/kg given by i.p. administration lack auditory preservation in this species.

Effect of noise conditioning on cisplatin-induced ototoxicity: a pilot study.

BACKGROUND: Cisplatin is a platinum-based chemotherapeutic agent that is highly effective in the treatment of cancer. Ototoxicity is an important dose-limiting adverse effect of cisplatin, in addition to nephrotoxicity. Studies have shown that cisplatin-induced ototoxicity is mainly a result of generated reactive oxygen species. Sulfur-containing compounds such as L-N acetylcysteine (L-NAC) and D-methionine (D-MET) have shown promising results as potent otoprotectors against cisplatin-induced ototoxicity in animal studies. MATERIAL/METHODS: In this study, we investigated a method to increase the efficacy of L-NAC and D-MET without increasing dose. Sprague Dawley rats were noise conditioned for 15 minutes immediately after intraperitoneal injection of 275 mg/kg L-NAC or 300 mg/kg D-MET. Another set of rats received 275 mg/kg L-NAC or 300 mg/kg D-MET alone, and 1 group underwent noise conditioning alone. All 5 groups were administered 14 mg/kg cisplatin intravenously 1 hour after otoprotector injection or 45 minutes after noise conditioning. RESULTS: Otoprotectors and noise conditioning, alone or in combination, were analyzed for their ability to reduce cisplatin-induced ototoxicity. The results indicated that the combination of 275 mg/kg L-NAC and noise conditioning afforded more otoprotection than 275 mg/kg L-NAC alone. In the case of D-MET, 300 mg/kg plus noise conditioning was little better than 300 mg/kg D-MET alone. In addition, we found that noise conditioning alone showed otoprotection against cisplatin-induced ototoxicity. CONCLUSIONS: The ability of noise conditioning to protect against cisplatin-induced ototoxicity requires additional study.

Cochlear repair by transplantation of human cord blood CD133+ cells to nod-scid mice made deaf with kanamycin and noise.

We investigated the fate of human cord blood CD133+ hematopoietic stem cells (HSC) transplanted intravenously (IV) into irradiated nod-scid mice previously made deaf by ototoxic treatment with kanamycin and/ or intense noise, to verify whether HSC engraft the cochlea and contribute to inner ear restoration, in vivo. We tested the presence of HLA.DQalpha1 by PCR, used for traceability of engrafted cells, finding evidence that HSC migrated to various host tissues, including the organ of Corti (OC). By histology, antibody and lectin-staining analysis, we confirmed that HSC IV transplantation in mice previously damaged by ototoxic agents correlated with the repair process and stimulation ex novo of morphological recovery in the inner ear, while the cochlea of control oto-injured, nontransplanted mice remained seriously damaged. Dual color FISH analysis also provided evidence of positive engraftment in the inner ear and in various mouse tissues, also revealing small numbers of heterokaryons, probably derived from fusion of donor with endogenous cells, for up to 2 months following transplantation. These observations offer the first evidence that transplanted human HSC migrating to the inner ear of oto-injured mice may provide conditions for the resumption of deafened cochlea, emerging as a potential strategy for inner ear rehabilitation.

Different strategies in treating noiseinduced hearing loss with N-acetylcysteine.

BACKGROUND: The cellular mechanisms leading to noise-induced hearing loss (NIHL) involve the generation of reactive oxygen species (ROS). Recent studies on glutathione (GSH) and N-acetylcysteine (NAC) show that they can protect the cochlea from ROS-derived damage, increasing the levels of endogenous cellular defences. The purpose of this study was to verify NAC's oto-protective efficacy and determine if drug administration timing influences the degree of oto-protection. MATERIAL/METHODS: Forty male Sprague Dawley albino rats were divided in four groups exposed to 8-kHz 105-dB SPL continuous noise. The groups were treated with diverse NAC administration modalities: group A received 4 injections during 48 hours (pre- and post-noise exposure), group B 1 injection prior to exposure, group C 1 injection 24 h after exposure, and group D served as untreated controls. The single injection dosage was 375 mg/kg; the controls received an equal volume of saline solution. Cochlear function was assessed by pre- and post-noise (after 168 hours) recordings of distortion product otoacoustic emissions (DPOAEs) and auditory brainstem responses (ABR). DPOAEs were obtained by three different asymmetric protocols (P1=60-50, P2=50-40, P3=40-30 dB SPL) for frequencies of 4-16 kHz. ABR responses were elicited by tone-bursts at 8 and 16 kHz. RESULTS: The most important outcome of the study was that the administration of NAC significantly reduced the threshold shifts in the treated animals. NAC provided different degrees of threshold reduction according to the timing of the drug injection. CONCLUSIONS: The role played by the timing of NAC injection was important for the OHC protection index. From a DPOAE perspective, the best protection scheme was observed in the group receiving NAC after noise exposure, but full recovery of cochlear function was not observed in any of the tested groups.