Comparison of faculty and student evaluations of the hybrid teaching of orthopedics during the COVID-19 pandemic

Background@#In the face of the COVID-19 pandemic and a country-wide lockdown, the University of the Philippines College of Medicine halted face-to-face teaching in exchange for online learning for its students. For the Learning Unit VI students, clinical rotations shifted to hybrid activities to continue learning activities while minimizing exposure risk. The Philippine General Hospital Department of Orthopedics introduced the following hybrid activities in its curriculum for Learning Unit VI students: 1) Online Lectures, 2) Online Departmental Conference, 3) Online Division Rounds, 4) Online SGDs, 5) Written Case, 6) Online Exams, 7) Preceptorship, Demo, Return Demo, and 8) Online OSCE. The department used a variety of platforms including synchronous sessions, asynchronous pre-recorded lectures, and face-to-face teaching, as appropriate. @*Objectives@#The study compared the faculty and student course evaluations of activities in the hybrid ORTHO 251 course. @*Methodology@#Faculty and students were asked to evaluate each activity according to the Course Evaluation By Students (CEBS), the standard questionnaire used by the college, to determine the overall rating of each activity as well as any differences between the two groups. @*Results@#The hybrid activities conducted in the ORTHO 251 course were rated as good or excellent by the faculty and students, with differences in a few activities. Consultants rated online exams as being less effectively integrated and that there was inadequate time allotment for online SGDs, written cases, and online exams. Meanwhile, students rated all activities higher in terms of stimulating self-directed learning. @*Conclusion@#With good to excellent outcomes, this study found that it has at least satisfactorily matched the learning platform to the learning component. While knowledge may be taught via asynchronous recorded lectures or reading materials, attitude and thinking processes are better formed through synchronous discussion. Skills in medical education, including Orthopedics, are still best taught via face-to-face demoreturn demo. With this information, the department can investigate the causes of these differences and improve on the identified weaknesses.

Exploratory Analysis of Patients With Gastric/Gastroesophageal Junction Adenocarcinoma With or Without Liver Metastasis From the Phase 3 RAINBOW Study

Purpose@#Liver metastasis (LM) is reported in approximately 40% of patients with advanced/ metastatic gastric/gastroesophageal junction adenocarcinoma (metastatic esophagogastric adenocarcinoma; mGEA) and is associated with a worse prognosis. This post-hoc analysis from the RAINBOW trial reported the efficacy, safety, and biomarker outcomes of ramucirumab and paclitaxel combination treatment (RAM+PAC) in patients with (LM+) and without (LM−) LM at baseline. @*Materials and Methods@#Patients (n=665) were randomly assigned on a 1:1 basis to receive either RAM+PAC (LM+: 150, LM−: 180) or placebo and paclitaxel (PL+PAC) (LM+: 138, LM−: 197). The overall survival (OS) and progression-free survival (PFS) were evaluated using stratified Kaplan–Meier and Cox regression models. The correlation of dichotomized biomarkers (VEGF-C, D; VEGFR-1,2) with efficacy in the LM+ versus LM− subgroups was analyzed using the Cox regression model with reported interaction P-values. @*Results@#The presence of LM was associated with earlier progression than those without LM, particularly in patients receiving PL+PAC (hazard ratio [HR], 1.68). RAM+PAC treatment improved OS and PFS irrespective of LM status but showed greater improvement in LM+ than that in LM− (OS HR, 0.71 [LM+] vs. 0.88 [LM−]; PFS HR, 0.47 [LM+] vs. 0.76 [LM−]).Treatment-emergent adverse events were similar between patients with and without LM. No predictive relationship was observed between biomarker levels (VEGF-C, D; VEGFR-1,2) and efficacy outcome (OS, PFS) (all interaction P-values >0.05). @*Conclusions@#RAM provided a significant benefit, irrespective of LM status; however, its effect was numerically stronger in patients with LM. Therefore, RAM+PAC is a clinically meaningful therapeutic option for patients with mGEA and LM.

The rotator cuff footprint in Filipinos: A cadaveric study

Introduction@#Rotator cuff tears are one of the common etiologies of shoulder pain. Rotator cuff repair is recommended for a patient who failed conservative treatment. Proper knowledge of the rotator cuff footprint is needed in restoring correct anatomy during the repair. The size of the footprint is important in determining the kind of repair.@*Objective@#This study aimed to define the average measurements of the rotator cuff footprint on the humerus in Filipino cadavers.@*Methods@#This is a descriptive, cross-sectional study of preserved human cadaver upper extremity specimens. We measured the length, width, and shape of the supraspinatus, infraspinatus, subscapularis, and teres minor.@*Results@#We obtained 27 upper extremity specimens. The median age of the source cadavers was 50.5 years with the equal male-to-female distribution. The mean measurement of the supraspinatus is 22.92 mm in length and 10.17 mm in width. The shape of the supraspinatus was found to be trapezoidal. The infraspinatus length was found to be 17.20 mm and the width at 10.72 mm. Its shape was found to be trapezoidal. The teres minor length was measured at 15.15 mm and the width at 11.04 mm. The shape was mostly trapezoidal but some were triangular. Finally, the subscapularis length was 17.68 mm while the width was 11.26 mm. The shape was trapezoidal or comma-shaped.@*Conclusion@#The average measurement of the rotator cuff footprint was found to be smaller in our study than reported in terms of length and width. The footprint shape was similar to the studies reported.

A declaração PRISMA 2020: diretriz atualizada para relatar revisões sistemáticas / The PRISMA 2020 statement: an updated guideline for reporting systematic reviews / Declaración PRISMA 2020: una guía actualizada para la publicación de revisiones sistemáticas

RESUMO A declaração dos Principais Itens para Relatar Revisões Sistemáticas e Meta-análises (PRISMA), publicada em 2009, foi desenvolvida para ajudar revisores sistemáticos a relatar de forma transparente por que a revisão foi feita, os métodos empregados e o que os autores encontraram. Na última década, os avanços na metodologia e terminologia de revisões sistemáticas exigiram a atualização da diretriz. A declaração PRISMA 2020 substitui a declaração de 2009 e inclui novas orientações para relato que refletem os avanços nos métodos para identificar, selecionar, avaliar e sintetizar estudos. A estrutura e apresentação dos itens foram modificadas para facilitar a implementação. Neste artigo, apresentamos a lista de checagem PRISMA 2020 de 27 itens, uma lista de checagem expandida que detalha as recomendações para relato para cada item, a lista de checagem PRISMA 2020 para resumos e os fluxogramas revisados para novas revisões e para atualização de revisões.

ABSTRACT The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement, published in 2009, was designed to help systematic reviewers transparently report why the review was done, what the authors did, and what they found. Over the past decade, advances in systematic review methodology and terminology have necessitated an update to the guideline. The PRISMA 2020 statement replaces the 2009 statement and includes new reporting guidance that reflects advances in methods to identify, select, appraise, and synthesise studies. The structure and presentation of the items have been modified to facilitate implementation. In this article, we present the PRISMA 2020 27-item checklist, an expanded checklist that details reporting recommendations for each item, the PRISMA 2020 abstract checklist, and the revised flow diagrams for original and updated reviews.

RESUMEN La declaración PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses), publicada en 2009, se diseñó para ayudar a los autores de revisiones sistemáticas a documentar de manera transparente el porqué de la revisión, qué hicieron los autores y qué encontraron. Durante la última década, ha habido muchos avances en la metodología y terminología de las revisiones sistemáticas, lo que ha requerido una actualización de esta guía. La declaración PRISMA 2020 sustituye a la declaración de 2009 e incluye una nueva guía de presentación de las publicaciones que refleja los avances en los métodos para identificar, seleccionar, evaluar y sintetizar estudios. La estructura y la presentación de los ítems ha sido modificada para facilitar su implementación. En este artículo, presentamos la lista de verificación PRISMA 2020 con 27 ítems, y una lista de verificación ampliada que detalla las recomendaciones en la publicación de cada ítem, la lista de verificación del resumen estructurado PRISMA 2020 y el diagrama de flujo revisado para revisiones sistemáticas.

Pectoralis Major Tendon as Landmark for Proximal Humerus Surgery: A Cadaveric Study on the Adult Filipino Population

@#OBJECTIVE: It is common to get lost during a comminuted proximal humerus surgery, and the pectoralis major insertion is always a constant. Therefore, this study aimed to do a cadaveric study on the Filipino population to assess the distance from the pectoralis major tendon to the top of the humeral head (PMT) as a reference during proximal humerus surgery. METHODS: This study dissected the shoulders of cadavers. The distance from the pectoralis major tendon insertion to the top of the humeral head (PMT) was measured using a caliper. This PMT distance was also correlated to the cadaver's height and sex. RESULTS: This study dissected 110 shoulders (55 cadavers | 24 females, 31 males). The median PMT was 5.40 cm for males and 4.90 cm for females, with a combined value of 5.40 cm overall. There was a direct and moderate correlation between the PMT with overall height. Height and PMT of both the left and right shoulder were significantly longer among males compared to females. The study showed that for every centimeter increase in the height of males, there was a corresponding 0.02 cm increase in the PMT, adding the constant factor of 1.83. A corresponding 0.04 cm increase in the PMT for females added the constant factor of -0.81. CONCLUSION; The pectoralis major tendon insertion is a consistent landmark that can accurately restore humeral length when reconstructing complex proximal humerus fractures where landmarks are otherwise lost because of comminution.

Pectoralis Major Tendon as Landmark for Proximal Humerus Surgery: A Cadaveric Study on the Adult Filipino Population

@#OBJECTIVE: It is common to get lost during a comminuted proximal humerus surgery, and the pectoralis major insertion is always a constant. Therefore, this study aimed to do a cadaveric study on the Filipino population to assess the distance from the pectoralis major tendon to the top of the humeral head (PMT) as a reference during proximal humerus surgery. METHODS: This study dissected the shoulders of cadavers. The distance from the pectoralis major tendon insertion to the top of the humeral head (PMT) was measured using a caliper. This PMT distance was also correlated to the cadaver's height and sex. RESULTS: This study dissected 110 shoulders (55 cadavers | 24 females, 31 males). The median PMT was 5.40 cm for males and 4.90 cm for females, with a combined value of 5.40 cm overall. There was a direct and moderate correlation between the PMT with overall height. Height and PMT of both the left and right shoulder were significantly longer among males compared to females. The study showed that for every centimeter increase in the height of males, there was a corresponding 0.02 cm increase in the PMT, adding the constant factor of 1.83. A corresponding 0.04 cm increase in the PMT for females added the constant factor of -0.81. CONCLUSION; The pectoralis major tendon insertion is a consistent landmark that can accurately restore humeral length when reconstructing complex proximal humerus fractures where landmarks are otherwise lost because of comminution.

Comparison of faculty and student evaluations of the hybrid teaching of orthopedics during the COVID-19 pandemic

Background@#In the face of the COVID-19 pandemic and a country-wide lockdown, the University of the Philippines College of Medicine halted face-to-face teaching in exchange for online learning for its students. For the Learning Unit VI students, clinical rotations shifted to hybrid activities to continue learning activities while minimizing exposure risk. The Philippine General Hospital Department of Orthopedics introduced the following hybrid activities in its curriculum for Learning Unit VI students: 1) Online Lectures, 2) Online Departmental Conference, 3) Online Division Rounds, 4) Online SGDs, 5) Written Case, 6) Online Exams, 7) Preceptorship, Demo, Return Demo, and 8) Online OSCE. The department used a variety of platforms including synchronous sessions, asynchronous pre-recorded lectures, and face-to-face teaching, as appropriate. @*Objectives@#The study compared the faculty and student course evaluations of activities in the hybrid ORTHO 251 course. @*Methodology@#Faculty and students were asked to evaluate each activity according to the Course Evaluation By Students (CEBS), the standard questionnaire used by the college, to determine the overall rating of each activity as well as any differences between the two groups. @*Results@#The hybrid activities conducted in the ORTHO 251 course were rated as good or excellent by the faculty and students, with differences in a few activities. Consultants rated online exams as being less effectively integrated and that there was inadequate time allotment for online SGDs, written cases, and online exams. Meanwhile, students rated all activities higher in terms of stimulating self-directed learning. @*Conclusion@#With good to excellent outcomes, this study found that it has at least satisfactorily matched the learning platform to the learning component. While knowledge may be taught via asynchronous recorded lectures or reading materials, attitude and thinking processes are better formed through synchronous discussion. Skills in medical education, including Orthopedics, are still best taught via face-to-face demoreturn demo. With this information, the department can investigate the causes of these differences and improve on the identified weaknesses.

Factors affecting utilization of antenatal care services and institutional delivery at Koghum in Jos South, Plateau State, Nigeria

Access to antenatal care services promotes safe motherhood and delivery. This study identified factors influencing the utilization of antenatal care services and health facility-based delivery. A cross sectional survey was conducted. Households were enumerated, and a systematic sampling method was deployed. A sample size of 200 was used. Of the 200 HHs, 198 women were interviewed using pretested semi-structured questionnaires. Data was collected on socio-demographics, attendance at the antenatal clinic (ANC), institutional delivery, and reasons for non-utilisation of ANC services. Data analysis was conducted using Epi Info version 3.5.3. The median age of respondents was 29 years (range: 17 - 55). Overall, 192 (97%) women had at least one ANC visit, 116 (58.6%) had ≥ 4 ANC visits and 93 (47.9%) commenced ANC in the second trimester in the last delivery. One hundred and twenty-five (63.1%) had their last delivery at home by a traditional birth attendant (TBA). The independent risk factors for utilization of ANC were partners' consent (aOR 11.5; 95% CI 1.6-82.3) and knowledge on the importance of ANC (aOR 7.4; 95% CI 1.4-38.6). Pregnant women in a polygamous union were less likely to use to ANC (aOR 0.1; 95% CI 0.0 - 0.4). Being a woman with a lower educational status was associated withassisted home delivery (aOR0.3; 95% CI 0.1-0.7). Most women utilized ANC services at least once. Community sensitization on the benefits of ANC and institutional delivery should be targeted at women in polygamous unions, with low educational level and without partner's consent for ANC

A Systems Biology Approach for Studying Heterotopic Ossification: Proteomic Analysis of Clinical Serum and Tissue Samples / 基因组蛋白质组与生物信息学报·英文版

Heterotopic ossification (HO) refers to the abnormal formation of bone in soft tissue. Although some of the underlying processes of HO have been described, there are currently no clinical tests using validated biomarkers for predicting HO formation. As such, the diagnosis is made radiographically after HO has formed. To identify potential and novel biomarkers for HO, we used isobaric tags for relative and absolute quantitation (iTRAQ) and high-throughput antibody arrays to produce a semi-quantitative proteomics survey of serum and tissue from subjects with (HO) and without (HO) heterotopic ossification. The resulting data were then analyzed using a systems biology approach. We found that serum samples from subjects experiencing traumatic injuries with resulting HO have a different proteomic expression profile compared to those from the matched controls. Subsequent quantitative ELISA identified five blood serum proteins that were differentially regulated between the HO and HO groups. Compared to HO samples, the amount of insulin-like growth factor I (IGF1) was up-regulated in HO samples, whereas a lower amount of osteopontin (OPN), myeloperoxidase (MPO), runt-related transcription factor 2 (RUNX2), and growth differentiation factor 2 or bone morphogenetic protein 9 (BMP-9) was found in HO samples (Welch two sample t-test; P < 0.05). These proteins, in combination with potential serum biomarkers previously reported, are key candidates for a serum diagnostic panel that may enable early detection of HO prior to radiographic and clinical manifestations.

Delay and Poor Diagnosis of Down Syndrome in KwaZulu-Natal; South Africa: A Retrospective Review of Postnatal Cytogenetic Testing

BACKGROUND:Down syndrome (DS) is the most common chromosomal disorder in newborns. Until 20 years ago DS was considered rare in black African children in South Africa (SA). Lack of awareness of DS on the part of medical staff in SA; and difficulty in diagnosing it; appear to persist. OBJECTIVES:To establish an epidemiological profile of DS and investigate the ability of clinicians in KwaZulu-Natal Province (KZN); SA; to make accurate clinical diagnoses of DS.METHODS:Records at the South African National Blood Service cytogenetic laboratory in Pinetown; KZN; were examined for all tests for clinically suspected DS undertaken during January 2009 - December 2013 and all cytogenetically proven DS test results. Age at diagnosis; the hospital from where the test was sent and type of chromosomal pattern for each confirmed DS test result were recorded. RESULTS:Of a total of 1 578 tests requested; 875 confirmed DS; indicating that clinicians correctly clinically diagnosed DS 55.4% of the time. The average age of cytogenetic diagnosis of DS was 1 year and 20 days. The minimum population prevalence of DS was 0.8/1 000.CONCLUSIONS: The diagnosis of DS is a challenge in KZN; potentiating missed opportunities for early intervention. The relatively low population prevalence of DS may be attributable to a lack of confirmatory cytogenetic tests or missed clinical diagnoses. It may also be attributable to a high mortality rate for children with DS in the province

Reducing Inter-Laboratory differences between semen analyses using z score and regression transformations

Background: Standardization of the semen analysis may improve reproducibility. We assessed variability between laboratories in semen analyses and evaluated whether a transformation using Z scores and regression statistics was able to reduce this variability

Materials and Methods: We performed a retrospective cohort study. We calculated between-laboratory coefficients of variation [CVB] for sperm concentration and for morphology. Subsequently, we standardized the semen analysis results by calculating laboratory specific Z scores, and by using regression. We used analysis of variance for four semen parameters to assess systematic differences between laboratories before and after the transformations, both in the circulation samples and in the samples obtained in the prospective cohort study in the Netherlands between January 2002 and February 2004

Results: The mean CVB was 7% for sperm concentration [range 3 to 13%] and 32% for sperm morphology [range 18 to 51%]. The differences between the laboratories were statistically significant for all semen parameters [all P<0.001]. Standardization using Z scores did not reduce the differences in semen analysis results between the laboratories [all P<0.001]

Conclusion: There exists large between-laboratory variability for sperm morphology and small, but statistically significant, between-laboratory variation for sperm concentration. Standardization using Z scores does not eliminate between-laboratory variability

Limiting the use of primary endocrine therapy in elderly women with breast cancer

Primary endocrine therapy (PET) is often included as a treatment option in elderly women with operable breast cancer. Elderly women tend to have pre-existing comorbidities and are often reluctant to undergo surgery. The benefit of surgery needs to be weighed against a relatively higher potential for operative morbidity and mortality, and a limited life expectancy. But while PET can provide relatively good locoregional control, it is not curative in nature and the possibility of local complications and metastasis remains. We retrospectively reviewed the outcome of PET in a series of 19 elderly women, older than 70 years of age, who had presented with operable non-metastatic breast cancer. Only about a third of these women were deemed medically unfit for surgery; the rest had declined surgery. Compliance was an issue, with almost half of these patients defaulting treatment and follow-up. Local control was achieved in most patients, but disease progression did occur in 5 patients. Three of these patients received additional treatment; which included surgery in 1 patient. PET should therefore not be considered an equivalent alternative to surgery in elderly women who were fi t to undergo surgery. However, having observed that only 1 of the 6 deaths in our study was related to breast cancer, PET does have a role in women whose life expectancy is more likely to be limited by coexisting morbidities than the breast cancer itself.

The use of traditional Chinese medicine among breast cancer patients: implications for the clinician

<p><b>INTRODUCTION</b>Traditional Chinese Medicine or Traditional Complementary Medicine (TCM) is commonly used in our culture. There are several concerns regarding its use in patients undergoing conventional treatments for breast cancer. In this study, we aimed to evaluate the prevalence and pattern of TCM use among our breast cancer patients, and to identify patients who were most likely to choose TCM.</p><p><b>MATERIALS AND METHODS</b>A total of 300 patients on active follow-up with Breast Service at Tan Tock Seng Hospital were interviewed using a structured questionnaire.</p><p><b>RESULTS</b>A total of 35% (104 of 296) of patients reported using TCM. The majority of the patients were introduced to TCM by family and friends following the diagnosis of breast cancer. All except 3 patients continued with recommended conventional therapy although most did not inform their clinicians of TCM use. None of the patients reported any serious adverse events and 75% of them perceived a benefit from TCM use. Younger patients and those of Chinese ethnicity were more likely to use TCM (P <0.01 and P = 0.03 respectively). There was no significant difference in the dialect group, religious beliefs and educational level between the 2 groups (P >0.05).</p><p><b>CONCLUSION</b>TCM use is common among our breast cancer patients, particularly the younger women. However, most patients do not inform their clinicians of TCM use while on recommended conventional therapies. It is therefore important for clinicians to initiate discussions regarding TCM use in order to be aware of potential unwanted drug interactions.</p>

Role of 18F-FDG PET/CT in the Carcinoma of the Uterus: A Review of Literature

In the present review we reported the value of 18F-fluorodeoxyglucose (FDG) PET/CT in face of uterine cancer, in terms of sensitivity, specificity and accuracy. Moreover, we made a comparison with the other imaging techniques currently used to evacuate these tumors including contrast-enhanced CT, contrast enhanced-MRI and transvaginal ultrasonography. FDG PET/CT has been reported to be of particular value in detecting occult metastatic lesions, in prediction of response to treatment and as a pro-gnostic factor.

Inside-out vein graft vs autogenous nerve graft in promoting axonal regeneration: An experimental study in a rat model

BACKGROUND: An experimental study was done to compare the efficacy of inside-out vein graft versus autogenous nerve graft as nerve conduit in promoting axonal regeneration in a rat model.METHODS: The study used 16 Spraque-Dawley rats randomly divided into two groups: the inside-out vein graft group and control group (autognous nerve graft). The outcomes measured were histomorphology (axon number and diameter), muscle twitch response (amplitude) and the walking track analysis at 2, 4 6 and 8 weeks.RESULTS: The inverted vein graft and control groups showed similar axon diameter (P=0.76), and axon number (P=0.85), weeks and similar muscle twitch responses (P=0.87) after eight weeks. The walking track analysis showed no significant difference between the two groups at eight weeks.CONCLUSION: The study showed that the inside-out vein graft group had similar motor recovery as compared to control group based on the muscle twitch analysis and walking track analysis in a rat model.In terms of histomorphometric analysis, the two groups were similar in terms of axon diameter and axon count.

Beyond Diagnostic Accuracy: The Clinical Utility of Diagnostic Tests

Like any other medical technology or intervention, diagnostic tests should be thoroughly evaluated before their introduction into daily practice. Increasingly, decision makers, physicians, and other users of diagnostic tests request more than simple measures of a test's analytical or technical performance and diagnostic accuracy; they would also like to see testing lead to health benefits. In this last article of our series, we introduce the notion of clinical utility, which expresses-preferably in a quantitative form-to what extent diagnostic testing improves health outcomes relative to the current best alternative, which could be some other form of testing or no testing at all. In most cases, diagnostic tests improve patient outcomes by providing information that can be used to identify patients who will benefit from helpful downstream management actions, such as effective treatment in individuals with positive test results and no treatment for those with negative results. We describe how comparative randomized clinical trials can be used to estimate clinical utility. We contrast the definition of clinical utility with that of the personal utility of tests and markers. We show how diagnostic accuracy can be linked to clinical utility through an appropriate definition of the target condition in diagnostic-accuracy studies.

A pterodactyloid pterosaur from the Upper Cretaceous Lapurr sandstone, West Turkana, Kenya

An isolated pterosaurian caudal cervical (~ postcervical) vertebra was recovered from the Upper Cretaceous Lapurr sandstone ofWest Turkana, northwestern Kenya. The vertebral centrum is short, wide, and dorsoventrally compressed. Although the specimen is lightly built similar to most pterosaurs, it is here referred to Pterodactyloidea and tentatively to the Azhdarchidae in that it lacks pneumatic features on both the centrum and neural arch. This represents one of the few pterosaurs recovered from the entirety of Afro-Arabia, the first pterosaur recovered from the Cretaceous of East Africa, and, significantly, a specimen that was recovered from fluvial deposits rather than the near-shore marine setting typical of most pterosaur discoveries.

Uma vértebra cervical caudal isolada de pterossauro (~ pós-cervical) foi recuperada do Cretáceo Superior do arenito de Lapurr do Oeste de Turkana, noroeste do Quênia. O centro vertebral é curto, largo e comprimido dorsoventralmente. Embora o espécime seja leve como grande parte dos pterossauros, ele é aqui referido a Pterodactyloidea e tentativamente a Azhdarchidae no que diz respeito à ausência de características pneumáticas tanto no centro quanto no arco neural. Este representa um dos poucos pterossauros recuperados do conjunto Afro-Arábia, o primeiro pterossauro proveniente do Cretáceo do Leste da África e, significativamente, um espécime que foi recuperado de depósitos fluviais e não do cenário marinho próximo da costa típico da maioria das descobertas de pterossauros.

Fabrication of an olfactometer for mosquito behavioural studies.

Background & objectives: Olfaction is the major sensory modality involved in the resource searching behaviour of insects including vector mosquitoes (Diptera: Culicidae). To date, our current countrywide knowledge on the host-seeking behaviour of Iranian mosquitoes is mainly confined to host preference which has exclusively come from field studies. Olfactometer is a scientific tool by which more naive aspects of man-vector contact can be clarified under controlled and less biased conditions. Methods: The wind tunnel and stimulus delivery system was constructed from acrylic materials based on previously introduced models with some modifications. Air supply and required light were ensured by a powerful compressor and incandescent bulbs, respectively. Desired level of temperature was maintained by controllable heating radiators. For humidity production a unique in-built piezo system was devised in the course of the air flow. Fine regulators facilitated the continuous generatation of the humidity at a preset level. Results: Titanium tetrachloride smoke plus monitoring of the wind speed revealed that the flow of air was proper and invariable. A desired level of humidity and temperature could be set up in just 10 and 15–45 min, respectively. These physical parameters varied only ±2% (humidity) and ±0.15ºC (temperature) in a typical 20 min duration. Conclusion: The first sophisticated olfactometer in the field of medical entomology in Iran is reported here. Fast set up and stability of physical parameters are its salient features. It is expected that with the aid of this olfactometer further information on the physiological principles of the host-seeking behaviour of mosquitoes become available soon.

Monitoramento da suscetibilidade a inseticidas em populações de Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) no Brasil / Monitoring the susceptibility to insecticides in Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) populations from Brazil

O monitoramento da suscetibilidade de pragas a praguicidas é essencial para programas de manejo da resistência. O objetivo deste trabalho foi verificar a variabilidade genética de populações de Bemisia tabaci (Gennadius), oriundas de diferentes áreas agrícolas, quanto a suscetibilidade a inseticidas no Brasil, por meio de dois testes diferentes. Quatro populações de mosca-branca foram testadas em relação a uma população suscetível de referência (SusIAC); duas oriundas de Goiás (GO-1 e GO-2) e outras duas da Bahia (BA-1 e BA-2). Uma técnica de bioensaio do tipo contato residual foi empregada para realização dos testes: 1) teste diagnóstico da resistência; e 2) teste para obtenção das linhas de suscetibilidade das populações. Os produtos utilizados foram acetamipride, imidaclopride, tiametoxam, clorpirifós e endosulfam. Utilizaram-se insetos adultos não separados por sexo e nem por idade nos testes. As avaliações foram realizadas em 24h, para o teste com endosulfam, e em 48h, para os demais produtos. Ambos os testes revelaram variabilidade genética quanto à suscetibilidade de mosca-branca aos inseticidas. No entanto, a discriminação entre as populações de B. tabaci foi mais evidente com o uso de testes diagnósticos. A população GO-2 foi significativamente menos suscetível aos produtos testados que a SusIAC, principalmente em relação aos neonicotinóides. A situação mais crítica de resistência de mosca-branca foi com tiametoxam, seguida pelo imidaclopride.

Monitoring the susceptibility of a pest population to pesticides is essential for resistance management programs. The objective of this research was to evaluate the genetic variability in pesticide susceptibility in populations of Bemisia tabaci (Gennadius) collected from different Brazilian agricultural regions through the use of two different tests. Four whitefly populations, two from Goiás state (GO-1 and GO-2) e two from Bahia state (BA-1 and BA-2), were tested against a susceptible reference one (SusIAC). A residual contact bioassay was used to evaluate the pesticide susceptibility of each population by using diagnostic concentration bioassays and by estimating the baseline susceptibility data to each one of the tested insecticides, acetamiprid, imidacloprid, thiamethoxam, chlorpyrifos and endosulfan. Adult insects of unknown age and sex were tested. Evaluations were performed after 24h for endosulfan and 48h for the other chemicals. Both procedures showed significant differences in the susceptibility to the pesticides among B. tabaci populations. However, the discrimination among B. tabaci populations was more evident with the use of diagnosis tests. The population GO-2 was significantly less susceptible to the tested pesticides than SusIAC, mainly to neonicotinoids. The most critical resistance situation of B. tabaci was detected to thiamethoxam, followed by imidacloprid.