Self-diagnosis of active head lice infestation by individuals from an impoverished community: high sensitivity and specificity

To compare sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of self-diagnosis for head lice infestation with visual inspection, we conducted a study in an urban slum in Brazil. Individuals were asked about active head lice infestation (self-diagnosis); we performed visual inspection and thereafter wet combing (gold standard). Of the 175 individuals included, 77 (44%) had an active head lice infestation. For self-diagnosis, sensitivity (80.5%), specificity (91.8%), PPV (88.6%) and NPV (85.7%) were high. Sensitivity of visual inspection was 35.1%. Public health professionals can use self-diagnosis as a diagnostic tool, to estimate accurately prevalence of pediculosis in a community, and to monitor ongoing intervention strategies.

HEAD LICE IN HAIR SAMPLES FROM YOUTHS, ADULTS AND THE ELDERLY IN MANAUS, AMAZONAS STATE, BRAZIL

A study of head lice infestations among young people, adults and elderly individuals was conducted from August 2010 to July 2013 in Manaus, AM, Northern Brazil. Hair samples collected from 1,860 individuals in 18 barber shops and beauty parlors were examined for the ectoparasite. The occurrence of pediculosis and its association with factors, such as sex, age, ethnicity, hair characteristics and the socioeconomic profile of salon customers, salon location and seasonal variation were determined. The overall occurrence rate was 2.84%. Occurrence was higher in hair samples from non-blacks and the elderly. Higher occurrence was also observed during kindergarten, elementary and junior education school holidays. The results indicate that the occurrence of head lice among young people, adults and the elderly in Manaus is relatively low compared to that determined in children and in other regions of the country. After children, the elderly were the most affected. The study also indicated the need to adopt additional procedures to improve surveys among the population with low or no purchasing power, which is usually the most affected by this ectoparasitic disease.

Prevalence and monthly distribution of head lice using two diagnostic procedures in several age groups in Uberlândia, State of Minas Gerais, Southeastern Brazil

Some epidemiological characteristics of head lice, Pediculus capitis, were studied using two procedures: cut hair analysis and head inspection. Higher prevalence rates were observed in the middle and at the end of the school terms. Both procedures indicated that children were the main reservoir for this type of pediculosis in Uberlândia.

Advances in radiochemotherapy in the treatment of head and neck cancer

New advances are being incorporated into the radiochemotherapy treatment of squamous cell carcinoma of the head and neck. Although the overall prognosis is poor in advanced stages, the possibility of incorporating combined protocols of chemotherapy and radiotherapy for organ preservation or for palliation in cases of recurrent/locally advanced stages that are not good surgical candidates must not be forgotten. In this context, there is an urgent need to incorporate quality of life questionnaires and functional evaluation into organ-preservation studies, as well as to assure the importance of surgical salvage after radiotherapy and chemotherapy protocols. The authors provide an extensive review of the advances occurring in the nonsurgical treatment of head and neck cancer. Special attention is given to different radiotherapy protocols, new chemotherapy combinations, molecular markers, and molecular therapy as well as the possibility of incorporating re-irradiation and adjuvant therapy after surgery.

Epidemiological Aspects of Head Lice in Children Attending Day Care Centres, Urban and Rural Schools in Uberlândia, Central Brazil

From November 1996 to March 2000, a total of 884 children between 0 and 15 years, from 11 institutions including day care centres, public urban and public rural schools in Uberlândia, State of Minas Gerais, central Brazil, were examined for head louse infestation. Children's sex, race, age and some hairs characteristics were shown to be associated to parasite infestation. A prevalence rate of 35% was found and the highest rates were observed in black, female children, with long, dark, wavy hairs. Hairs density and thickness did not seem to influence significantly the distribution of this pediculosis in Uberlândia's schoolchildren. Differences observed between the prevalence rates of head lice in children from the urban institutions suggest there is a greater epidemiological heterogeneity in this group when compared to the rural schoolchildren.

A transient increase in total head phosphotyrosine levels is observed upon the emergence of Aedes aegypti from the pupal stage

Phosphorylation and dephosphorylation of protein tyrosine residues constitutes a major biochemical regulatory mechanism for the cell. We report a transient increase in the total tyrosine phosphorylation of the Aedes aegypti head during the first days after emergence from the pupal stage. This correlates with an initial reduction in total head protein tyrosine phosphatase (PTP) activity. Similarly, phosphotyrosine (pTyr)-containing bands are seen in extracts prepared from both male and female heads and are spread among a variety of structures including the antennae, proboscis and the maxillary palps combined with the proboscis. Also, mosquitoes treated with sodium orthovanadate, a classical PTP inhibitor, show reduced blood-feeding activity and higher head tyrosine phosphorylation levels. These results suggest that pTyr-mediated signalling pathways may play a role in the initial days following the emergence of the adult mosquito from the pupal stage.

Low-level laser therapy for the prevention of low salivary flow rate after radiotherapy and chemotherapy in patients with head and neck cancer

Abstract Objective: To determine whether low-level laser therapy can prevent salivary hypofunction after radiotherapy and chemotherapy in head and neck cancer patients. Materials and Methods: We evaluated 23 head and neck cancer patients, of whom 13 received laser therapy and 10 received clinical care only. An InGaAlP laser was used intra-orally (at 660 nm and 40 mW) at a mean dose of 10.0 J/cm2 and extra-orally (at 780 nm and 15 mW) at a mean dose of 3.7 J/cm2, three times per week, on alternate days. Stimulated and unstimulated sialometry tests were performed before the first radiotherapy and chemotherapy sessions (N0) and at 30 days after the end of treatment (N30). Results: At N30, the mean salivary flow rates were significantly higher among the laser therapy patients than among the patients who received clinical care only, in the stimulated and unstimulated sialometry tests (p = 0.0131 and p = 0.0143, respectively). Conclusion: Low-level laser therapy, administered concomitantly with radiotherapy and chemotherapy, appears to mitigate treatment-induced salivary hypofunction in patients with head and neck cancer.

A risk infection simulation model for fusarium head blight of wheat

Fusarium Head Blight (FHB) is a disease of great concern in wheat (Triticum aestivum). Due to its relatively narrow susceptible phase and environmental dependence, the pathosystem is suitable for modeling. In the present work, a mechanistic model for estimating an infection index of FHB was developed. The model is process-based driven by rates, rules and coefficients for estimating the dynamics of flowering, airborne inoculum density and infection frequency. The latter is a function of temperature during an infection event (IE), which is defined based on a combination of daily records of precipitation and mean relative humidity. The daily infection index is the product of the daily proportion of susceptible tissue available, infection frequency and spore cloud density. The model was evaluated with an independent dataset of epidemics recorded in experimental plots (five years and three planting dates) at Passo Fundo, Brazil. Four models that use different factors were tested, and results showed all were able to explain variation for disease incidence and severity. A model that uses a correction factor for extending host susceptibility and daily spore cloud density to account for post-flowering infections was the most accurate explaining 93% of the variation in disease severity and 69% of disease incidence according to regression analysis.

Weather requirements and rain forecast to time fungicide application for Fusarium head blight control in wheat

The aim of this study was to determine the minimum conditions of wetness duration and mean temperature required for Fusarium head blight infection in wheat. The weather model developed by Zoldan (2008) was tested in field experiments for two wheat cultivars grown in 2005 (five sowing dates) and 2006 (six sowing dates) in 10 m² plots with three replicates. The disease was assessed according to head incidence (HI), spikelet incidence (SI), and the interaction between these two methods was called head blight severity (HBS). Starting at the beginning of anthesis, air temperature and head wetness duration were daily recorded with an automatic weather station. With the combination of these two factors, a weather favorability table was built for the disease occurrence. Starting on the day of flowering beginning (1 - 5% fully exserted anthers), the sum of daily values for infection favorability (SDVIF) was calculated by means of a computer program, according to Zoldan (2008) table. The initial symptoms of the disease were observed at 3.7% spikelet incidence, corresponding to 2.6 SVDFI. The infection occurs in wheat due to rainfall which results in spike wetting of > 61.4 h duration. Rainfall events forecast can help time fungicide application to control FHB. The name of this alert system is proposed as UPF-scab alert.

Modelling head loss along emitting pipes using dimensional analysis

Local head losses must be considered in estimating properly the maximum length of drip irrigation laterals. The aim of this work was to develop a model based on dimensional analysis for calculating head loss along laterals accounting for in-line drippers. Several measurements were performed with 12 models of emitters to obtain the experimental data required for developing and assessing the model. Based on the Camargo & Sentelhas coefficient, the model presented an excellent result in terms of precision and accuracy on estimating head loss. The deviation between estimated and observed values of head loss increased according to the head loss and the maximum deviation reached 0.17 m. The maximum relative error was 33.75% and only 15% of the data set presented relative errors higher than 20%. Neglecting local head losses incurred a higher than estimated maximum lateral length of 19.48% for pressure-compensating drippers and 16.48% for non pressure-compensating drippers.

Safety and tolerability of controlled-release oxycodone on postoperative pain in patients submitted to the oncologic head and neck surgery

Objective: To evaluate the safety and tolerability of controlled-release oxycodone in the treatment of postoperative pain of head and neck oncologic resections.Methods: We conducted a prospective, observational and open study, with 83 patients with moderate to severe pain after head and neck oncological operations. All patients received general anesthesia with propofol, fentanyl and sevoflurane. Postoperatively, should they have moderate or severe pain, we began controlled-release oxycodone 20 mg 12/12 b.i.d on the first day and 10 mg b.i.d. on the second. We assessed the frequency and intensity of adverse effects, the intensity of postoperative pain by a verbal numeric scale and the use of rescue analgesia from 12 hours after administration of the drug and between 7 and 13 days after the last oxycodone dose.Results: The most common adverse events were nausea, vomiting, dizziness, pruritus, insomnia, constipation and urinary retention, most mild. No serious adverse events occurred. In less than 12 hours after the use of oxycodone, there was a significant decrease in the intensity of postoperative pain, which remained until the end of the study. The rescue medication was requested at a higher frequency when the opioid dose was reduced, or after its suspension.Conclusion: Controlled release oxycodone showed to be safe and well tolerated and caused a significant decrease in post-operative pain.

Prevalence of alterations in chest computerized tomography in patients with head and neck cancer

Objective: to assess the prevalence of abnormalities found by computed tomography (CT) of the chest in patients with squamous cell carcinoma of the head and neck. Methods: we retrospectively analyzed chest CT exams of 209 patients with squamous cell carcinoma of the head and neck. The CT findings were stratified as inflammatory / infectious, parenchymal, nodular uncharacteristic and nodular metastatic / tumoral Results: alterations were diagnosed in 66.6% of patients. Of these, 25.3% represented emphysema; 18.8%, uncharacteristic micronodules; 12.9%, metastases; 11.9%, thoracic lymph node enlargements; and in 6.6% we detected active pulmonary tuberculosis or its sequelae, pneumonia or inflammatory / infectious signs and pleural thickening or effusion. Conclusion: the prevalence of exams with alterations and the considerable rate of detected metastases indicate that chest CT should be required for diagnostic and / or staging in cases of head and neck cancer.