Zwitterionic gold nanorods: low toxicity and high photothermal efficacy for cancer therapy.

Novel "zwitterionic" gold nanorods (Au NRs) were constructed through a facile ligand exchange process between cetyltrimethylammonium bromide (CTAB)-Au NRs and the zwitterionic block polymer {poly(2-methacryloyloxyethyl phosohorylcholine)-b-poly(lipoic methacrylate) (pMPC-b-pLA)}. In vitro, they exhibited low dark cytotoxicity and a high therapeutic efficacy to cancer cells. Their blood circulation half-life in vivo (t1/2, ∼10 h) was 20-fold longer than that of CTAB-Au NRs (t1/2, <30 min). After intravenous administration, they accumulated in tumour sites via an enhanced permeability and retention (EPR) effect and enabled destruction of human xenograft tumours in mice after exposure of the tumour location to NIR laser irradiation at 808 nm. These studies showed that the "zwitterionic" Au NRs had low toxicity and high photothermal efficacy both in vitro and in vivo due to the suprahydrophilic, biocompatible zwitterionic polymer coating layer. They may have the potential to be a promising NIR PTT agent in the biomedical field.

Effect of irrigation with Tetraclean on bacterial leakage of obturated root canals.

The purpose of the study presented here was to evaluate the effect of Tetraclean, Hypoclean, Chlor-XTRA, 2% chlorhexidine and 6% sodium hypochlorite/17% EDTA as a final irrigant on bacterial leakage of the root canal. One hundred and fifty-five extracted human maxillary central incisors were randomly divided into five experimental groups of 25 teeth each and two control groups of 15 teeth each. The root canals in each group were irrigated with 2 ml of the relevant irrigant between each filing. The root canals in group 5 were irrigated with 5 ml of 17% EDTA at the end of root canal preparation. The teeth in each group were obturated with gutta-percha and AH-26 sealer. Positive control teeth were obturated with a single gutta-percha cone without sealer, and negative controls were obturated in the same way as experimental groups. The coronal portion of each root was placed in contact with inoculum of Enterococcus faecalis in Brain Heart Infusion (BHI) culture media. Findings showed that the mean number of days for bacterial penetration in the Tetraclean group was greater than for other experimental groups. On the other hand, the Chlor-XTRA Vista group showed the fewest mean number of days for bacterial leakage.

Capsulorrhaphy in the management of liver hydatid cyst.

INTRODUCTION: Hydatid disease is a major health problem in some parts of the world. There are several nonoperative and operative ways to treat hydatic disease. The aim of this retrospective study is to assess the rate of postoperative complications, mortality rate, hospitalization period, and recurrence for capsulorrhaphy method, and to compare it with other hydatic cyst management techniques. MATERIAL AND METHODS: An open surgical procedure using capsulorrhaphy technique was performed on 250 patients (130 men and 120 women) with uncomplicated hydatic cysts in the Northwest of Iran, between 1989 and 2011. RESULTS: The patients stayed in the hospital between 4 and 10 days, with an average of 5 days. Of the patients, 233 (93.2%) were discharged without any complications, 9 (3.6%) developed a wound infection in the abdominal wall, and 7 (2.8%) developed pulmonary atelectasis. Those who developed an infection or an atelectasis stayed in the hospital for few more days for conservative treatments. One of the patients (0.4%) had external biliary fistula and bile leak, which was treated with surgery and Roux-en-Y cystojejunostomy. During follow-ups (13.2 ± 8.5 months), incisional hernias occurred in 5 (2%) patients and hydatid cyst recurrence affected 7 (2.8) patients. The mortality rate was zero amongst the studied patients. CONCLUSION: Compared to other techniques in the literature, the results presented in the current work indicate that capsulor-rhaphy is an efficient method in terms of decreased postoperative complications, recurrence, and hospitalization period, and is a safe method with low morbidity and zero mortality rates.

Residual activity of cetrimide and chlorhexidine on Enterococcus faecalis-infected root canals.

Effective final irrigation regimen is an important step in order to achieve better disinfection and ensure residual antimicrobial effects after root canal preparation. The aim of this study was to compare the residual antimicrobial activity of 0.2% cetrimide, and 0.2% and 2% chlorhexidine in root canals infected with Enterococcus faecalis. Biofilms of E. faecalis were grown on uniradicular roots for 4 weeks. After root canal preparation, root canals were irrigated with 17% ethylenediaminetetraacetic acid (EDTA) to remove the smear layer. The roots were randomly divided into three experimental groups (n=26) according to the final irrigating solution: Group I, 5 mL 0.2% cetrimide; Group II, 5 mL 0.2% chlorhexidine; and Group III, 5 mL 2% chlorhexidine. Samples were collected for 50 days to denote the presence of bacterial growth. The proportion of ungrown specimens over 50 days was evaluated using the nonparametric Kaplan-Meier survival analysis. Differences among groups were tested using the log-rank test and the level of statistical significance was set at P<0.05. The highest survival value was found with 2% chlorhexidine, showing statistically significant differences from the other two groups. At 50 days, E. faecalis growth was detected in 69.23% specimens in Groups I and II, and in 34.61% specimens of Group III. There were no significant differences between 0.2% cetrimide and 0.2% chlorhexidine. Final irrigation with 2% chlorhexidine showed greater residual activity than 0.2% chlorhexidine and 0.2% cetrimide in root canals infected with E. faecalis.

Evaluation of the antifungal activity of four solutions used as a final rinse in vitro.

The aim of the study was to compare the antifungal activity of 1.3% sodium hypochlorite (NaOCl), 2% chlorhexidine (CHX), MTAD and Tetraclean as a final rinse against Candida albicans in a human tooth model in vitro. Ninety extracted human maxillary central and lateral incisor teeth were randomly divided into four groups each with 20 teeth, a positive and a negative control each with five teeth. After preparing the root canals, teeth were inoculated with Candida albicans (ATCC 10261) and incubated for 72 h. Teeth were divided into four experimental groups according to the irrigation solution as follows: NaOCl, CHX, MTAD and Tetraclean. After culturing aliquots from the experimental teeth on Sabouraud 4% dextrose agar, colony-forming units were counted. The results showed that 1.3% NaOCl and 2% CHX were equally effective and significantly superior to MTAD and Tetraclean (P < 0.05). Furthermore, antifungal efficacy of Tetraclean was significantly superior to MTAD (P < 0.05).

Photodynamic inactivation of chlorin e6-loaded CTAB-liposomes against Candida albicans.

BACKGROUND AND OBJECTIVES: Antimicrobial photodynamic inactivation (PDI) is a promising therapeutic modality for the treatment of local infections. To increase the efficacy of PDI, chlorine e6 (Ce6) was encapsulated in cationic CTAB-liposomes composed of various ratios of dimyristoyl-sn-glycero-phosphatidylcholine (DMPC) and the cationic surfactant, cetyltrimethyl ammonium bromide (CTAB). The PDI efficacy of the liposomal-Ce6 was assessed in vitro against susceptible and drug-resistant clinical isolates of Candida albicans (C. albicans) as well as in infected burn wounds. STUDY DESIGN/MATERIALS AND METHODS: Ce6 was encapsulated in CTAB-liposomes by the film hydration method. Particle size distribution and zeta potential of the cationic liposomes were measured using a Zetasizer Nano-ZS. UV-visible spectra were used to measure lipid/Ce6 (L/C) ratio and drug entrapment efficiency while differential scanning calorimetry (DSC) was used to study the thermotropic behavior of DMPC liposomes upon CTAB addition. In vivo PDI efficacy was carried out in an infected burn wound using a rat model. RESULTS: The increase in zeta potential and a shift in the phase transition temperature (Tm ) upon CTAB addition confirmed its entrapment within the lipid bilayers of the liposome. Meanwhile, the CTAB addition did not affect the Ce6 entrapment efficiency and physical attributes of the liposomes. In vitro studies showed that the PDI effect of the Ce6-loaded CTAB-liposomes was dependent on the lipid to Ce6 molar ratio (L/C), particle size and the concentration of CTAB in the liposomes. The lower L/C ratio and smaller liposomes exerted significantly higher PDI effects. In addition, an increase in the CTAB to lipid ratio led to a significant increase in the PDI effect of Ce6 against susceptible and drug-resistant clinical isolates of C. albicans after light illumination. CONCLUSIONS: Our results indicate that a low L/C ratio, high positive charge, and small particle size of CTAB-liposomes significantly enhances their PDI efficacy against C. albicans.

Potential use of cetrimonium bromide as an apoptosis-promoting anticancer agent for head and neck cancer.

A potential therapeutic agent for human head and neck cancer (HNC), cetrimonium bromide (CTAB), was identified through a cell-based phenotype-driven high-throughput screen (HTS) of 2000 biologically active or clinically used compounds, followed by in vitro and in vivo characterization of its antitumor efficacy. The preliminary and secondary screens were performed on FaDu (hypopharyngeal squamous cancer) and GM05757 (primary normal fibroblasts), respectively. Potential hit compounds were further evaluated for their anticancer specificity and efficacy in combination with standard therapeutics on a panel of normal and cancer cell lines. Mechanism of action, in vivo antitumor efficacy, and potential lead compound optimizations were also investigated. In vitro, CTAB interacted additively with gamma radiation and cisplatin, two standard HNC therapeutic agents. CTAB exhibited anticancer cytotoxicity against several HNC cell lines, with minimal effects on normal fibroblasts; a selectivity that exploits cancer-specific metabolic aberrations. The central mode of cytotoxicity was mitochondria-mediated apoptosis via inhibition of H(+)-ATP synthase activity and mitochondrial membrane potential depolarization, which in turn was associated with reduced intracellular ATP levels, caspase activation, elevated sub-G(1) cell population, and chromatin condensation. In vivo, CTAB ablated tumor-forming capacity of FaDu cells and delayed growth of established tumors. Thus, using an HTS approach, CTAB was identified as a potential apoptogenic quaternary ammonium compound possessing in vitro and in vivo efficacy against HNC models.

Evaluation of different chemical agents on the germinative layer of sheep hydatid cyst after implantation to peritoneal cavity of BALB/c.

In spite of the use of protoscolocidal agents during hydatid cyst surgery, a notable rate of disease recurrence in postoperation patients is still observed. The question remains whether living protoscolices lead to recurrence or the recurrence is due to the remainder of the germinative layer in the peritoneal cavity. The aim of this study was in vivo evaluation of different chemical (protoscolicidal) solutions on the germinative layer of the hydatid cyst. The germinative layer of sheep hydatid cyst was separated under sterile condition, divided into 0.25-cm(2) parts, and exposed to 0.5% cetrimide, 0.5% silver nitrate, 20% hypertonic saline, 15% dextrose and 25% dextrose, and normal saline as negative control for 2 min. The exposed germinative layers were implanted into the peritoneal cavity of 90 Balb/C mice (15 mice in each group). After nine months, the peritoneum was evaluated macroscopically as well as microscopically for the presence of any hydatid cyst. No hydatid cyst was observed in the peritoneal cavity of the exposed mice. The role of the germinative layer for inducing hydatid cysts in mice is questionable. However, the present study showed that the germinative layer had no role in the induction of hydatid cyst in these laboratory animals.

Preoperative antiseptics in clean/contaminated maxillofacial and oral surgery: prospective randomized study.

In order to show the effectiveness of preoperative antiseptic mouthwash the authors undertook a prospective study in 120 patients who underwent elective surgery under general or local anesthesia. Patients were allocated toone of 4 groups, depending on whether the oral cavity was washed preoperatively with 1% cetrimide, chlorhexidine, povidon-iodine or sterilized normal saline solution (control group). Aerobic and anaerobic bacterial samples were taken from the inferior vestibulum mucosa before surgery, 5 min after the start of the operation and at the end of the procedure. The results show a statistically significant reduction in bacterial counts during procedures in which antiseptics are used to wash the oral cavity preoperatively. 1% cetrimide solution was the most successful in reducing intra-oral bacterial counts and produced the longest lasting antiseptic effect. Chlorhexidine is a good option for procedures longer than 1 hour, while povidon-iodine is recommended for procedures lasting up to 1 hour. Normal saline reduced bacterial counts in the specimen taken 5 min after washing but this short-lasting effect is due to mechanical cleansing rather than the antiseptic effect.

Hydatid disease of bone.

A case of primary hydatid disease of the right femur is reported that presented with pathological fracture and was diagnosed at the time of exploration for biopsy. The patient was treated by removal of all cysts, irrigation with scolicidal solution, bone grafting and immobilisation of the fracture followed by four cycles of oral Albendazole. Eosinophilia and serological tests reverted to normal but the patient died due to acute myocardial infarction six months later. This uncommon condition should be considered in the differential diagnosis of pathological fractures, bone pain or osteolytic lesions, especially in patients of rural and farmer background.

Hepatic hydatid cyst rupturing into sub-diaphragmatic space and pericardial cavity.

A ten-year-old male child presented with a large hepatic hydatid cyst which ruptured into the sub-diaphragmatic space and pericardial cavity, giving rise to a pericardial effusion. This communication between the hydatid cyst and the pericardium was documented on computerised tomographic scan of the chest and abdomen. The cyst was aspirated carefully and then enucleated. There was an associated right-sided reactionary pleural effusion. The pericardial effusion and pleural effusion resolved on albendazole therapy and did not require surgical intervention.

Metabolic acidosis induced by cetrimide-chlorhexidine solution in hydatid cyst surgery.

A patient with a large hydatid cyst of the left lobe of the liver developed metabolic acidosis following rather liberal use of cetrimide-chlorhexidine solution as a scolicidal agent. The progress and management of this complication are described in the patient is being reported.

Results of laparoscopic treatment of hydatid cysts of the liver.

BACKGROUND: We have previously reported on the laparoscopic treatment of hydatid cysts of the liver. We now report the successful treatment of 18 cysts in 12 patients with a median follow-up of 12 months. METHODS: The standard treatment in the open technique was performed laparoscopically. The main concern was to prevent spillage of the hydatid fluid, for which the puncture and evacuation of the cyst is carried under scolicidal agents cover using 1% cetrimide, thus decreasing the chances of recurrence. RESULTS: In this group of patients we had one biliary leak that ceased spontaneously and one recurrence of hydatid cyst but not in the same lobe. CONCLUSIONS: We conclude that laparoscopic evacuation of hydatid cysts is a successful operation comparable to the open technique, with the added advantages of the laparoscopic approach.

Efficacy of tumoricidal agents in vitro and in vivo.

Implantation of exfoliated tumour cells can give rise to local recurrence of colorectal cancer and it has been recommended that the bowel lumen be lavaged with a tumoricidal agent. This study identified which tumoricidal agents are currently used in Scotland and investigated their efficacy in vitro and in vivo. Cytotoxic efficacy was tested in vitro by a clonogenic assay and in vivo by a rat model with viable intraluminal tumour cells. Overall 70 per cent of surgeons used a tumoricidal agent during colorectal cancer surgery. Povidone-iodine, sodium hypochlorite and chlorhexidine-cetrimide were all effective at killing tumour cells in vitro but were all inactivated by the presence of 25 per cent whole blood in vitro. With 10(5) cells in vivo povidone-iodine and sodium hypochlorite significantly (P < 0.02) reduced the incidence of tumour growth while chlorhexidine-cetrimide had no significant effect. With 10(6) cells povidone-iodine had no effect on the incidence of tumour growth. Tumoricidal agents have effective cytotoxicity in vitro but are only weakly cytotoxic in vivo.

[Bacterial vaginosis during chemotherapy for gynecological neoplasms. A therapeutic proposal]. / La vaginosi batterica in corso di chemioterapia per tumori ginecologici. Proposta terapeutica.

Bacterial vaginosis (BV) is a well characterized disease, defined Amsel's criteria, whose incidence is significantly increased during chemotherapy for gynecologic malignancies, as previously reported by the authors. Nine patients out of 14 (64%) who were receiving adjuvant chemotherapy for gynecologic tumors showed a clinical and laboratory evidence of bacterial vaginosis and were treated with cetyltrimethilammonium naproxenate vaginal douches. Results were analyzed up to the completion of oncologic chemotherapy: a high efficacy and tolerability for the topical treatment was demonstrated in all cases.

Laparoscopic treatment of hydatid cysts of the liver.

We report for the first time treatment of hydatid cyst of the liver laparoscopically. The patient is a 27-year-old man who presented to our hospital with a 6-week history of recurrent right-upper-quadrant pain with abdominal ultrasound findings compatible with hydatid cyst of the liver. The cyst was approached laparoscopically using the same hydatid asepsis as in open surgery. The cyst was evacuated laparoscopically and marsupialized, and its remaining cavity was packed with omentum. The patient did well postoperatively and was discharged home on the third postoperative day. He had minimal biliary leak that ceased spontaneously on the fifth postoperative day.

The efficacy of agents employed to prevent anastomotic recurrence in colorectal carcinoma.

Forty-eight of 72 surgeons canvassed in the South West of England (67%) routinely use an intraluminal cytotoxic agent to prevent suture-line recurrence following partial resection of the large bowel for cancer. The most popular agents are chlorhexidine-cetrimide preparations (n = 14), mercuric perchloride (12), povidone-iodine (7) and water (12); noxythiolin, sodium hypochlorite and silver nitrate are used occasionally. The mean duration of treatment is 2 minutes. When assayed for cytotoxity against tumour cells freshly prepared from human colorectal carcinomas (n = 10), both chlorhexidine-cetrimide and povidone-iodine were rapidly lethal at a wide range of concentrations (5-100%). Mercuric perchloride (0.2%) was similarly effective, but up to 20% of tumour cells remained viable after exposure to noxythiolin and nearly 30% with water alone. Chlorhexidine-cetrimide and povidone-iodine are the agents of choice to kill malignant cells exfoliated into the colorectal lumen.