Laboratory Diagnosis of Intrathecal Synthesis of Immunoglobulins: A Review about the Contribution of OCBs and K-index.

The diagnosis of MS relies on a combination of imaging, clinical examinations, and biological analyses, including blood and cerebrospinal fluid (CSF) assessments. G-Oligoclonal bands (OCBs) are considered a "gold standard" for MS diagnosis due to their high sensitivity and specificity. Recent advancements have involved the introduced of kappa free light chain (k-FLC) assay into cerebrospinal fluid (CSF) and serum (S), along with the albumin quotient, leading to the development of a novel biomarker known as the "K-index" or "k-FLC index". The use of the K-index has been recommended to decrease costs, increase laboratory efficiency, and to skip potential subjective operator-dependent risk that could happen during the identification of OCBs profiles. This review aims to provide a comprehensive overview and analysis of recent scientific articles, focusing on updated methods for MS diagnosis with an emphasis on the utility of the K-index. Numerous studies indicate that the K-index demonstrates high sensitivity and specificity, often comparable to or surpassing the diagnostic accuracy of OCBs evaluation. The integration of the measure of the K-index with OCBs assessment emerges as a more precise method for MS diagnosis. This combined approach not only enhances diagnostic accuracy, but also offers a more efficient and cost-effective alternative.

Long-standing gustatory and olfactory dysfunction in COVID-19 patients: a prospective study.

PURPOSE: Our study aimed to describe recovery of gustatory dysfunction (GD) and olfactory dysfunction (OD) in COVID-19 patients, and to analyze variables associated with early or late recovery. METHODS: Telephone surveys were administered during an 18-month follow-up after COVID-19 diagnosis. One hundred and thirty-two included patients rated olfactory and gustatory function at each follow-up. RESULTS: One hundred and twenty-nine patients reported GD, of whom 91 (70.5%) reported severe GD, and 99 patients reported OD, of whom 84 (84.9%) reported severe OD. Seventy-two/129 (55.8%) and 52/99 (52.5%) patients reported an improvement in GD and in OD during the first 7 days from the onset, respectively. At 3-month follow-up, 110/120 patients (85.3%) recovered from GD, while 80/99 patients (80.8%) recovered from OD. At 18-month follow-up, a total of 120/129 patients (93.0%) recovered from GD and 86/99 patients (86.9%) recovered from OD; while 10 patients (7.0%) still reported GD and 13 patients (13.1%) still reported OD. Severe GD/OD at presentation were associated with late complete recovery of taste/smell (p = 0.019 and p = 0.034, respectively). Improvement over the first 7 days from onset was significantly associated with faster recovery (p < 0.001). CONCLUSIONS: More than 80% of patients reported complete recovery of olfactory/gustatory function in the first 3 months after symptom onset. At 18-month follow-up, patients reporting complete recovery of gustatory and olfactory function were 93% and 87%, respectively. Severity of chemosensory dysfunction at the onset was negatively correlated to recovery, and improvement of taste and/or smell function within the first 7 days from symptom onset was significantly associated with early resolution.

The development of National Safety and Quality Digital Mental Health Standards.

OBJECTIVE: Digital mental health services offer innovative ways for individuals to access services but are not without risk. Our objective was to develop National Safety and Quality Digital Mental Health (NSQDMH) Standards that improve the quality of digital mental health service provision and protect service users from harm. METHOD: The NSQDMH Standards were developed by adapting the National Safety and Quality Health Service (NSQHS) Standards and adding components highlighted through a national consultation process as critical to the safety and quality of services. Further public consultation and pilot testing assisted in refining the NSQDMH Standards. RESULTS: The NSQDMH Standards comprise three standards-Clinical and Technical Governance, Partnering with Consumers, and Model of Care-and were launched in November 2020. CONCLUSIONS: The NSQDMH Standards provide a quality assurance mechanism to improve digital mental health care in Australia.

The attraction trick: males in early stages of disease become more chemically attractive to Nile tilapia (Oreochromis niloticus) females.

In aquatic systems, olfaction plays an important role in acquiring information about the social environment and influences important behaviours in various contexts, including predator avoidance, foraging, aggressive and reproductive behaviour and mate selection. As the presence of diseases might modify individual odour, fish may use the variability in conspecifics' odours as an indicator of the health status and infectious load of potential mates. Here, female Nile tilapia were tested for their ability to detect infected males and discriminate between bacterial infected and uninfected individuals by means of chemical cues. Females were allowed to choose between the odours of males infected by Aeromonas hydrophila bacteria and uninfected males. The findings show that female Nile tilapia initially showed a preference for infected males in terms of their first choice in a dichotomous choice test, but the total duration of time spent with the stimulus from infected males was not longer than that for the uninfected males. This may indicate that males at early stages of infection, i.e., without advanced clinical signs of infection, emit odours that allow them to enjoy the benefits of socialization when the infection is not yet detected by conspecifics. Thus, in the context of reproduction, males might attract female partners and have some chance of reproducing, before being avoided.

A systematic review of different treatment strategies for the squamous cell carcinoma of the posterior pharyngeal wall.

OBJECTIVE: To perform a systematic review of the literature available about the posterior pharyngeal wall squamous cell carcinomas, with a special focus on oncologic outcomes. METHODS: A comprehensive research was performed on PubMed/MEDLINE, Google Scholar, and Cochrane Library datasets for published studies meeting the established criteria. The last search was conducted on December 8, 2019. RESULTS: Eleven studies were included in the review, for a total of 534 patients (median age 60.4; male: n = 359, 67.2%). Six of the studies evaluated the oncologic outcomes of primary surgery, while three studies focused on results achieved through primary radiotherapy. Two studies evaluated both surgery and radiotherapy outcomes for the treatment of early or advanced posterior pharyngeal wall carcinoma. CONCLUSIONS: Primary surgery associated with adjuvant radiotherapy would seem to ensure better oncologic outcomes, especially for locally advanced tumors. Moreover, this systematic review showed that oro- and hypo-pharyngeal wall tumors are similar in terms of clinical and biological behavior.

Gingival crevicular fluid response to protocols of non-surgical periodontal therapy: A longitudinal evaluation.

CONTEXT AND AIM: Gingival crevicular fluid (GCF) volume reflects the level of periodontal inflammation. This secondary analysis aimed to evaluate the GCF volume in patients submitted to non-surgical periodontal therapies under a split-mouth design. MATERIALS AND METHODS: GCF volume of 25 participants (47.24 ± 6.47 years) with moderate-to-severe chronic periodontitis was collected at Days 0, 30, 60, 90, 120, 270, and 450. The participants were submitted to three different non-surgical therapies randomly assigned per quadrant [GI: supragingival control (Supra) as only intervention (one quadrant); GII: Supra plus scaling and root planing (SRP) on Day 0 (two quadrants); GIII: Supra on Day 0 and SRP 30 days later (one quadrant)]. During treatment (0-60 days) and maintenance (90-450 days) participants were submitted to supragingival plaque control reinforcements. GCF volumes were analyzed after logarithmic transformation (log10) and linear models were used for intra- and inter-group comparisons, considering the data dependence. RESULTS: Baseline GCF volumes were similar between groups (GI: 0.39 ± 0.22 µl; GII: 0.42 ± 0.26 µl; GIII: 0.41 ± 0.14 µl;P > 0.05). At Day 60, GCF volumes were significantly reduced (GI: 0.20 ± 0.13 µl; GII: 0.18 ± 0.11 µl; GIII: 0.22 ± 0.13 µl; P < 0.001), without inter-groups differences. These results were maintained along maintenance period (P > 0.05). Even in sites bleeding on probing (BOP) + the means of GCF volume did not differ between groups (P > 0.05). CONCLUSIONS: All therapies determined reductions on the GCF volume along time. Supragingival plaque control modulated the subgingival area during the study, reinforcing the importance of this control over the subgingival inflammatory response.

Selective ϖ-1 oxidation of fatty acids by CYP147G1 from Mycobacterium marinum.

BACKGROUND: Cyp147G1 is one of 47 cytochrome P450 encoding genes in Mycobacterium marinum M, a pathogenic bacterium with a high degree of sequence similarity to Mycobacterium tuberculosis and Mycobacterium ulcerans. Cyp147G1 is one of only two of these cyp genes which are closely associated with a complete electron transfer system. METHODS: The substrate range of the enzyme was tested in vitro and the activity of CYP147G1 was reconstituted in vivo by co-producing the P450 with the ferredoxin and ferredoxin reductase. RESULTS: Substrates of CYP147G1 include fatty acids ranging from octanoic to hexadecanoic acid. CYP147G1 catalysed the selective hydroxylation of linear and ω-2 methyl branched fatty acids at the ω-1 position (≥ 98%). Oxidation of ω-1 methyl branched fatty acids generated the ω and ω-1 hydroxylation products in almost equal proportions, indicating altered position of hydrogen abstraction. CONCLUSIONS: This selectivity of fatty acid hydroxylation inferred that linear species must bind in the active site of the enzyme with the terminal methyl group sequestered so that abstraction at the CH bonds of the ω-1 position is favoured. With branched substrates, one of the methyl groups must be close to the compound I oxygen atom and enable hydroxylation at the terminal methyl group to compete with the reaction at the ω-1CH bond. GENERAL SIGNIFICANCE: Hydroxy fatty acids are widely used for industrial, food and medical purposes. CYP147G1 demonstrates high regioselectivity for hydroxylation at a sub-terminal position on a broad range of linear fatty acids, not seen in other CYP enzymes.

Self-perception of patients after periodontal treatment: A longitudinal study.

AIMS: To investigate the perceptions of subjects regarding nonsurgical periodontal treatment over a period of 1 year. SETTINGS AND DESIGN: This is a secondary analysis of a randomized clinical trial, in a longitudinal observational design. METHODS: Nineteen subjects (47.24 ± 6.47 years) with moderate to severe periodontitis completed a questionnaire at two different times after a nonsurgical periodontal treatment: 30 (T1) and 390 days (T2). The questionnaire with 40 items was divided into three domains: 1-perception of changes in clinical signs of periodontal disease, 2-psychological aspects of the subject regarding their oral health status, and 3-satisfaction with the treatment. STATISTICAL ANALYSIS: Each response on the Likert scale initially showed scores ranging from 1 to 5 points. The results for each question were dichotomized into 1 or 0, respectively, showing if the subject was favorable or unfavorable to treatment. A descriptive data analysis was performed, assessing the agreement of the results in T1 and T2 (Kappa). RESULTS: The results generally showed a favorable perception related to the treatment and continued satisfaction over time. The exceptions were in regards to gingival recession, persistent bleeding and bad breath, and difficulty in performing the mechanical control imposed by the professional. CONCLUSION: It was concluded that the therapy used was satisfactory to the subjects and that a favorable perception was maintained after 1 year of follow-up.

Influência do tabagismo em doenças peri-implantares / The influence of smoking on periimplant diseases

A peri-implantite é uma doença bacteriana infecciosa que afeta tecidos moles e duros em torno do implante, promovendo a perda de osseointegração. Entre os fatores de risco, podemos considerar o tabagismo e doença periodontal, pois, quando presentes, podem exacerbar a perda de altura óssea, dificultar a cicatrização após cirurgia mucogingival, e causar a falha do implante. Com base nisso, este estudo objetiva fazer uma revisão de literatura sobre a relação entre tabagismo e doenças peri-implantares. A pesquisa foi realizada na base de dados pubmed. O principal achado foi que o tabagismo é considerado um fator de risco para falha de implantes dentários e para o desenvolvimento da peri-implantite. Na comparação de fumantes com não fumantes, os autores consideraram que a falha no tratamento do implante é maior nos fumantes, bem como na presença de doenças peri-implantes. As taxas de falha de implantes colocados em seios maxilares enxertados são observadas duas vezes mais em fumantes do que em não fumantes, além da maior da perda óssea marginal.

Peri-implantite is an infectious bacterial disease that affects soft and hard tissues around the implant, promoting the loss of osseointegration. Among the risk factors, we can consider tobacco and periodontal disease important factors that can exacerbate loss of bone height, worse healing after mucogingival surgery and implant failure. The aim of this study was to review the literature about the relation between smoking and peri-implant diseases. The search was performed in the pubmed database. The main finding was that smoking is considered a risk factor for failure of dental implants and for the development of peri-implantitis. In the comparison of smokers with nonsmokers, the authors considered that the failure of implant treatment is greater in smokers, as well as the presence of peri-implant diseases. The failure rates of implants placed in maxillary sinuses grafted in smokers are more than two-fold observed than in nonsmokers and smokers show increased marginal bone loss.

The "One Shot" Diode Laser Stapedotomy.

OBJECTIVE: The purpose of this study was to evaluate the effectiveness and the safety of diode laser stapedotomy, through the functional results analysis. MATERIALS AND METHODS: A total of 179 primary cases of otosclerosis that had been operated on with a diode laser technique from 2004 to 2012 were retrospectively reviewed. Preoperative, 1 month postoperative, and late annual follow-up audiograms (up to 8 years) were obtained in all the cases. Mean preoperative and 1 month postoperative pure-tone average (500-1000-2000-4000 Hz) bone conduction thresholds (PTA-BCs), air conduction (AC) hearing outcomes for 8 kHz and mean postoperative air-bone gap (PTA-ABG) closure were analyzed. RESULTS: The mean preoperative (pre) PTA-BC was 24.22 dB (±8.7 SD) whereas the mean postoperative (post) PTA-BC was 21.11 dB (±9.1 SD). The mean preoperative 8 kHz AC was 56.41 dB (±22.86 SD) and the postoperative 8 kHz AC was 52.56 dB (±24.35 SD). A statistically significant improvement of the PTA-BC post and of the postoperative 8 kHz AC was observed. The 1 month ABG closure within 10 dB in 89.02% of the patients and within 20 dB in 97.69% of the patients was obtained with statistically significant stability over long-term follow-up. No major complications occurred in the series. CONCLUSIONS: The use of diode laser with high power and short time exposure as setup can be considered a safe, precise, and useful tool in stapes surgery.

Effects of sleep deprivation on different phases of memory in the rat: dissociation between contextual and tone fear conditioning tasks.

Numerous studies show that sleep deprivation (SD) impacts negatively on cognitive processes, including learning and memory. Memory formation encompasses distinct phases of which acquisition, consolidation and retrieval are better known. Previous studies with pre-training SD induced by the platform method have shown impairment in fear conditioning tasks. Nonetheless, pre-training manipulations do not allow the distinction between effects on acquisition and/or consolidation, interfering, ultimately, on recall of/performance in the task. In the present study, animals were first trained in contextual and tone fear conditioning (TFC) tasks and then submitted to SD with the purpose to evaluate the effect of this manipulation on different stages of the learning process, e.g., in the uptake of (new) information during learning, its encoding and stabilization, and the recall of stored memories. Besides, we also investigated the effect of SD in the extinction of fear memory and a possible state-dependent learning induced by this manipulation. For each task (contextual or TFC), animals were trained and then distributed into control, not sleep-deprived (CTL) and SD groups, the latter being submitted to the modified multiple platform paradigm for 96 h. Subsets of eight rats in each group/experiment were submitted to the test of the tasks, either immediately or at different time intervals after SD. The results indicated that (a) pre- but not post-training SD impaired recall in the contextual and TFC; (b) this impairment was not state-dependent; and (c) in the contextual fear conditioning (CFC), pre-test SD prevented extinction of the learned task. Overall, these results suggest that SD interferes with acquisition, recall and extinction, but not necessarily with consolidation of emotional memory.

Supragingival treatment as an aid to reduce subgingival needs: a 450-day investigation.

This study investigated the clinical effects of using a supragingival biofilm control regimen (SUPRA) as a step prior to scaling and root planing (SRP). A split-mouth clinical trial was performed in which 25 subjects with periodontitis (47.2 ± 6.5 years) underwent treatment (days 0­60) and monitoring (days 90­450) phases. At Day 0 (baseline) treatments were randomly assigned per quadrant: SUPRA, SRP and S30SRP (SUPRA 30 days before SRP). The full-mouth visible plaque index (VPI), gingival bleeding index (GBI), periodontal probing depth (PPD), bleeding on probing (BOP), and clinical attachment loss (CAL) were examined on days 0, 30, 60, 90, 120, 270, and 450. Baseline data were similar among all groups. From days 0 to 60, the groups showed similar significant decreases in VPI and GBI. Reductions in PPD for the SRP (3.39 ± 0.17 to2.42 ± 0.16 mm) and S30SRP (3.31 ± 0.11 to 2.40 ± 0.07 mm) groups were greater (p < 0.05) than those for the SUPRA group. This pattern was also observed for BOP. Attachment gain was similar and greater for the SRP (3.34 ± 0.28 to 2.58 ± 0.26 mm) and S30SRP (3.25 ± 0.21 to 2.54 ± 0.19 mm) groups compared to the SUPRA group. Results were maintained from day 90 forward. Overall, the S30SRP treatment reduced the subgingival treatment needs in 48.16%. Performance of a SUPRA step before SRP decreased subgingival treatment needs and maintained the periodontal stability over time.

Neonatal Intensive-Care Unit Graduates Show Persistent Difficulties in an Intra-Dimensional Shift Card Sort.

Neonatal intensive-care unit (NICU) graduates, a group at risk for attention problems and ADHD, performed an intra-dimensional shift card sort at 34, 42, 51, and 60 months to assess executive function and to examine effects of individual risk factors. In the 'silly' game, children sorted cards (airplanes and dogs) so they were not the same as targets. In the 'same' game they did the opposite. Performance on the 'silly' game was poor, especially when it was presented first. Success in following 'silly' game rules improved with age, and was significantly linked to maternal education and birth weight for gestational age, a measure of intrauterine stress. Degree of CNS injury differentiated children who completed the task from children who did not, and also affected the need to repeat instructions in the 'same' game. These results confirm an increased likelihood of impairments in executive function during preschool years in NICU graduates.

Efeito do controle do biofilme supragengival na condição periodontal de pacientes tabagistas: uma revisão sistemática / Effect of supragingival plaque control on periodontal disease in smokers: a systematic review

Objetivo: avaliar, por meio de uma revisão sistemática da literatura, se o controle do biofilme supragengival, em pacientes fumantes, é capaz de alterar os critérios clínicos e microbiológicos associados à periodontites. Metodologia: a estratégia de busca envolveu o uso de bases de dados eletrônicos: MEDLINE e Cochrane Oral Health Group, entre 1965 e Janeiro de 2009. As palavras-chave utilizadas no MEDLINE foram: supragingival plaque control AND (subgingival OR debridement OR scaling and root planing OR non surgical OR oral hygiene OR periodontitis OR gingivitis OR plaque subgingival OR lost attachment OR probing pocket depth OR bleeding).Nessa busca foram localizadas 307 referências bibliográficas, contemplando os mais variados tipos de estudos. No Cochrane as palavras-chave aplicadas foram: supragingival plaque control AND oral hygiene, sendo obtidas 137 referências. A aplicação de critérios de inclusão permitiu que 4 estudos fossem avaliados na íntegra: 3 ensaios clínicos com seleção randômica de sítios experimentais e 1 ensaio clínico sem randomização. Resultados: dos estudos avaliados, 2 avaliaram somente a intervenção supragengival e 2avaliaram, também, a intervenção subgengival. Pôde-se observar que o controle supragengival, como intervenção única, foi capaz de determinar redução dos indicadores clínicos e microbiológicos periodontais, sendo os melhores resultados condicionados a um adequado programa de controle do biofilme supragengival. Conclusão: o estudo mostrou que o efeito do controle de biofilme supragengival em pacientes tabagistas é capaz de melhorar significativamente os indicadores clínicos e microbiológicos associados à gengivite e periodontite.

Aim: to conduct a systematic review of the literature to assess whether supragingivalplaque control is able to change clinical and microbiological markers associated with periodontal disease in smokers. Methodology: articles published between 1965 and January 2009 and indexed in the MEDLINE and Cochrane Oral Health Group databases were browsed. The following keywords were used on MEDLINE: supragingival plaque control AND (subgingival OR debridement OR scaling and root planing OR non surgical OR oral hygiene OR periodontitis OR gingivitis OR plaque subgingival OR lost attachment OR probing pocket depth OR bleeding);the search on MEDLINE yielded 307 references, including different types of studies. On Cochrane, the keywords employed were supragingival plaque control AND oral hygiene; this search yielded 137 studies. After application of inclusion criteria, four studies were selected for full-text review: three clinical trials with randomly selected experimental sites and one nonrandomized clinical trial. Results: of the four studies reviewed, two assessed the effects of supragingival plaque control alone, whereas the other two assessed both supragingival and subgingival interventions.It was possible to observe that supragingival plaque control alone was able to reduce clinical and microbiological indicators associated with periodontal disease, and that the best results were obtained after an adequate supragingival plaque control regimen. Conclusion: our study showed that supragingival plaque control is able to significantly improve clinical and microbiological markers associated with gingivitis and periodontitis in smokers.

Glucocorticoids are not responsible for paradoxical sleep deprivation-induced memory impairments.

STUDY OBJECTIVES: To evaluate whether paradoxical sleep deprivation-induced memory impairments are due to release of glucocorticoids, by means of corticosterone inhibition with metyrapone. DESIGN: The design was a 2 (Groups [control, paradoxical sleep-deprived]) x 2 (Treatments [vehicle, metyrapone]) study, performed in 2 experiments: Acute treatment (single injection given immediately after 96 hours of sleep deprivation) and chronic treatment (8 injections, twice per day, throughout the sleep-deprivation period). Animals were either paradoxical sleep-deprived or remained in their home cages for 96 hours before training in contextual fear conditioning and received intraperitoneal injections of a corticosterone synthesis inhibitor, metyrapone. Memory performance was tested 24 hours after training. SUBJECTS: Three-month old Wistar male rats. MEASUREMENTS: Freezing behavior was considered as the conditioning index, and adrenocorticotropic hormone and corticosterone plasma levels were determined from trunk blood of animals sacrificed in different time points. Animals were weighed before and after the paradoxical sleep-deprivation period. RESULTS: Acute metyrapone treatment impaired memory in control animals and did not prevent paradoxical sleep deprivation-induced memory impairment. Likewise, in the chronic treatment, paradoxical sleep-deprived animals did not differ from control rats in their corticosterone or adrenocorticotropic hormone response to training, but still did not learn as well, and did not show any stress responses to the testing. Chronic metyrapone was, however, effective in preventing the weight loss typically observed in paradoxical sleep-deprived animals. CONCLUSIONS: Our results suggest that glucocorticoids do not mediate memory impairments but might be responsible for the weight loss induced by paradoxical sleep deprivation.

Comparative analysis between hard- and soft-filament toothbrushes related to plaque removal and gingival abrasion.

OBJECTIVE: The aim of this split-mouth, examiner-blind study was to compare the dental plaque removal and incidence of gingival abrasion associated with the use of hard- and soft-filament toothbrushes. METHODOLOGY: The test group consisted of 20 non-dental students, mean age 25 years. After a three-day period of plaque accumulation following the use of a disclosing solution, the Quigley-Hein Plaque Index was recorded, while the presence of gingival abrasion was measured from photographs. Pairs of quadrants 1-3 and 2-4 were allocated to supervised brushing with hard- or soft-filament toothbrushes for 30 seconds, limited to the buccal aspects of the teeth. Plaque levels and gingival abrasion were again assessed. Initial and final values of the plaque index and the mean number of abrasions were compared with the Friedman and Wilcoxon tests (p < or = 0.05). RESULTS: Plaque indices were reduced significantly from a baseline of 4.12 in both groups to 1.21 after the use of hard-filament toothbrushes, and to 1.67 after the use of soft-filament toothbrushes. The use of hard-filament toothbrushes resulted in a significantly higher mean number of lesions when compared to the soft-filament toothbrushes; 11.6 and 7.9, respectively (p = 0.018). CONCLUSION: Hard-filament toothbrushes remove more plaque than soft filament brushes, but also cause a higher number of gingival abrasions.

Quantitative determination of acetaminophen in pharmaceutical formulations using differential scanning calorimetry. Comparison with spectrophotometric method.

In this paper our previous researches dealing with compatibility, thermoanalytical characterization, the kinetics of thermal degradation of acetaminophen, either pure or contained in some commercial pharmaceutical formulations, have found applications outlets. In a previous investigation the possible interactions between acetaminophen and four excipients contained in the commercial pharmaceutical formulations were tested. As a continuation of this research in the present study an analytical method based on differential scanning calorimetry (DSC) was applied to determine the acetaminophen content of four commercial pharmaceutical formulations. For a fifth drug it was shown that the method is not applicable owing to observed incompatibility with one of the excipients. Finally, the analytical results obtained were compared with those derived from two UV spectrophotometric methods (one, i.e., "direct method," recommended by the Pharmacopeia and the other based on the first-order derivative UV spectra).

Disinfection of gutta-percha cones with chlorhexidine and sodium hypochlorite.

OBJECTIVES: To evaluate the effectiveness of chlorhexidine (CHX) or sodium hypochlorite (NaOCl) in disinfecting gutta-percha cones, to verify contamination of gutta-percha cones in their boxes, and to identify microorganisms after intentional contamination by handling cones. STUDY DESIGN: Gutta-percha cones contaminated in vitro with several microorganisms were left in contact with tested disinfecting solutions for different times, sterility of storage boxes was evaluated by immersing cones in broth medium, and the microorganisms most frequently found in handling cones were identified using biochemical tests. RESULTS: CHX was not effective in eliminating Bacillus subtilis spores on gutta-percha cones after 72 h of contact with the disinfecting substance. 5.25% NaOCl eliminated spores from gutta-percha after 1 min of disinfection. The cones evaluated from their boxes did not show contamination in 94.5% of the cases. The microbial genus most frequently found after intentional contamination with gloves was Staphylococcus. CONCLUSION: 5.25% NaOCl is an effective agent for a rapid disinfection of gutta-percha cones.

Efficacy of selective lymph node dissection in clinically negative neck.

OBJECTIVE: The purpose of this study was to evaluate the efficacy of selective neck dissection (SND) for elective treatment of the clinically negative neck in head and neck squamous cell carcinoma (SCC). METHODS: A retrospective review was undertaken on 91 previously untreated patients with T1-4 SCC of oral cavity (23), oropharynx (5), hypopharynx (7), larynx (56), and clinically negative neck (N0), undergoing 126 SND from January 1990 to March 1999 at a single institution. Twenty-five patients received postoperative radiation therapy on the basis of histologic evidence of >2 positive nodes, extracapsular spread (ECS), and/or the presence of advanced primary lesion. RESULTS: On pathologic examination the average number of lymph nodes was 20.5 per neck, occult disease was detected in 14 (11.11%) of 126 necks; of necks with positive nodes, 6 (42.85%) of 14 had ECS. The median follow-up was 36 months. Overall recurrence rate (local, regional, and distant) was 12.8% (11 of 91). Recurrent disease developed in the neck of one patient, outside the dissected field. There was no difference in recurrence rate between pN0 and pN+ patients, as well as between pN+ with or without ECS. Overall survival rate was 84% (77 of 91), with a statistically significant difference between pN0 and pN+ necks. CONCLUSION: SND seems to be a pragmatic approach that is as effective as comprehensive procedures for staging and treating the clinically negative neck.