Population genetic structure and demographic history of Spodoptera frugiperda (Lepidoptera: Noctuidae): implications for insect resistance management programs

BACKGROUND

Spodoptera frugiperda is a destructive pest that often imposes difficult management due to its high polyphagy and rapid insecticide resistance evolution. Knowledge of species diversification, population structure, and host preference can aid efforts to manage pest populations. Here, we investigated the patterns of hybridization, genetic structure, and gene flow in S. frugiperda populations, discussing how we can apply this knowledge to insect resistance management programs in South America.

RESULTS

The corn-strain CS-h2 of S. frugiperda was the most frequent haplotype in all sampled populations. Spodoptera frugiperda populations are experiencing demographic expansion, and the ecoregions partially explain the genetic structure and not strains. We did not find a correlation between gene flow and susceptibility levels to flubendiamide and lufenuron insecticides, but populations with high LC₅₀ sent a great number of migrants to all other locations, maintaining resistance alleles in the geographic range.

CONCLUSION

High levels of population admixture, including between corn- and rice-strains, were found in sampled populations. We showed that S. frugiperda immigrants will not necessarily cause an increase in LC₅₀ upon arrival in a new location but will assure the constant presence of resistance alleles in the area. Increases in LC₅₀ largely depend on the local pesticide management adopted in the areas. Our results indicate that pesticide resistance management must be adopted on a local or small regional scale. © 2019 Society of Chemical Industry.

Lymph node retrieval rates in melanoma: a quality assessment parameter

INTRODUCTION

Regional lymph node dissection (rlnd) for melanoma with nodal metastasis is a specialized procedure that is associated with improved disease-specific survival in selected patients. Furthermore, there is evidence that a higher lymph node retrieval rate (lnrr) is associated with improved local control. Currently, no consensus has been reached on the definition of an adequate lnrr. A minimum lnrr has been proposed as a quality assessment parameter that has to be validated.

METHODS

We conducted a retrospective cohort analysis at the Princess Margaret Cancer Centre (University Health Network, Toronto, ON). The lnrrs for all patients who underwent rlnd for malignant cutaneous melanoma during 2000-2010 were recorded. Indications for rlnd were a positive sentinel lymph node biopsy or clinical lymphadenopathy (palpable or radiologically detected).

RESULTS

Of the 207 identified rlnds, 146 (70.5%) were subsequent to a positive sentinel lymph node biopsy, and 61 (29.5%) were performed for clinical lymphadenopathy. The median lnrr was 24 nodes (range: 9-47 nodes; 10th percentile: 14 nodes) for axillary rlnd, 12 nodes (range: 5-30 nodes; 10th percentile: 8 nodes) for inguinal rlnd, and 16 nodes (range: 10-21 nodes; 10th percentile: 11 nodes) for ilioinguinal rlnd. The results were similar when comparing patients with positive sentinel lymph nodes and those with clinical lymphadenopathy, and the same surgical techniques were used in both groups.

CONCLUSIONS

The lnrrs at our institution are similar to rates reported at other tertiary-care melanoma centres. A minimum acceptable lnrr can be considered a quality assessment parameter in the surgical management of melanoma with nodal metastasis.

Homozygosity for a factor XII mutation in one female and one male patient with hereditary angio-oedema

Hereditary angio-oedema (HAE) with normal C1 inhibitor is associated with heterozygous mutations in the factor XII gene (FXII-HAE). We report two Brazilian FXII-HAE families segregating the mutation c.983 C>A (p.Thr328Lys). In each family, one patient with a homozygous mutation was found. The homozygous female patient in family 1 displayed a severe phenotype. However, this falls within the clinical phenotype spectrum reported for heterozygous female mutation carriers. The homozygous male patient in family 2 also showed a severe phenotype. This finding is intriguing, as to our knowledge, it is the first such report for a male FXII-HAE mutation carrier. In the rare instances in which male mutation carriers are affected, a mild phenotype is typical. The present findings therefore suggest that homozygous FXII-HAE mutation status leads to a severe phenotype in females and males, and to an increased risk of manifest symptoms in the latter.

An update on percutaneous nephrolithotomy: lessons learned from the CROES PCNL Global Study

Since its introduction in late 1970's, percutaneous nephrolithotomy (PNL) has undergone an evolution in both equipment and technique. This evolution still continues today in the era of minimally invasive treatment options, and is evidenced by the numerous publications. PNL is generally advantageous in the management of large renal stones (>1.5-2 cm) with high stone-free rates and considerable complication rates. However this technique is especially competing with retrograde intrarenal surgery and laparoscopic techniques. Therefore the CROES Global PNL Study Group prospectively collected data of over 5800 patients managed with PNL worldwide and analyzed the data in detail, producing more than 25 scientific papers. And this update focuses on the lessons learned from the CROES PCNL Global Study.

The early days of pandemic (H1N1) 2009 virus infection in the central region of Portugal

BACKGROUND

The first case of pandemic (H1N1) 2009 virus infection was diagnosed in the central region of Portugal on June 16, 2009, in a woman infected in Canada.

METHODS

The aim of our study was, first to characterize the clinical and epidemiologic aspects of all the patients with clinical manifestations included in the definition of case for investigation with samples submitted to diagnosis of the pandemic (H1N1) 2009 virus infection, in the central region of Portugal; second to assess the precision of the case definition of case for investigation considered in the study according to the presence or the absence of fever at the moment of clinical observation. We reviewed the medical records of all the patients presenting with Influenza like-illness classified as case for investigation and the first cases of patients infected with the new pandemic (H1N1) 2009 virus, diagnosed in the central region of Portugal during the pandemic period between June and August, 2009, were analyzed. Real-time reverse-transcriptase polymerase-chain-reaction (RT-PCR) testing was used to confirm the pandemic (H1N1) 2009 virus infection. Data collection was performed on a standardized paper format in agreement with the General Health Directorate.

RESULTS AND DISCUSSION

Pandemic (H1N1) 2009 virus infection was confirmed in 255 patients. Overall, median age was 23 years and 42.7 % were included in the category of 20 to 29 years. Confirmed infection in patients with less than 2 years or greater than 50 years was a rare event. The first cases were imported from Europe, namely France, Spain and England. On a second phase, pandemic (H1N1) 2009 virus infection was acquired in the south of Portugal (Algarve), before de diagnosis of the first domestic case. The incidence rate for pandemic (H1N1) 2009 virus infection was 10.7 per 100,000 persons and was different according to the district. It was higher in the district of Coimbra and Guarda were the main roads connecting to Europe are. The median calculated incubation period for the for pandemic (H1N1) 2009 virus infection was 2 days. The length of the clinical manifestations until the patients look for medical observation had a median time of 2 days. All the cases were of mild to moderate severity. No deaths were observed.

CONCLUSIONS

The early days of pandemic (H1N1) 2009 virus infection was mild in our region. Most affected patients were young adults, with the extreme categories ages of life being spared. Early detection and diagnosis, combined with stringent isolation and treatment procedures could have slowed the spread of the infection in our region.

[Prevalence of hereditary hemochromatosis among healthy workers. Diagnostic value of transferrin saturation assay]

AIM

Hereditary hemochromatosis is the most common inherited disorder in white population (2-8 cases per 1000 habitants). Hemochromatosis is characterized by increased intestinal absorption of iron leading to its deposition into multiple organs. An early diagnosis and proper management with frequent phlebotomies are known to improve life expectancy and quality of life. Diagnosis is suggested by an elevated Transferrin saturation (TS) (more than 60%).

METHOD

Prospective study of the level of TS among 1131 healthy workers, who came to the Security and Hygiene Official Centre for their annual revision had been undertaken.

RESULTS

Twenty-wo workers had high TS; in 10 of them the increase of TS was confirmed on repeated determinations. Liver biopsy was performed in six (and refused by the other four), eventually a diagnosis of hemochromatosis was confirmed in three (in-group prevalence of 2.6 per 1000 people).

CONCLUSIONS

In our experience, TS is the most appropriate initial screening test for detecting hereditary hemochromatosis in a normal population.

[The Miller Fisher syndrome. Review of the cases of the Santa Maria Hospital]

A benign syndrome of acute ophthalmoplegia, ataxia, and areflexia is commonly known as the Miller Fisher syndrome. It is generally believed that Miller Fisher syndrome is a type of Guillain-Barré syndrome, but several authors believe it to be a separate clinical entity caused by a central nervous system lesion. Eight patients with Miller Fisher syndrome diagnosis, admitted to our department in the last 20 years, were reviewed. Neurophysiological studies were carefully reviewed. Our patients had a clinical presentation and evolution identical to that described previously. Neurophysiological abnormalities were found in all patients and were characteristic of a sensory axonal neuropathy, with damage of the facial nerves and occasional demyelination of peripheral nerves. The pattern of abnormalities is distinct from the usual features seen in Guillain-Barré syndrome. The CT scan, MRI, and Evoked Potentials investigations in our patients did not confirm central nervous system lesion. Nevertheless we did not exclude the possibility of coexisting damage to the central nervous system in some patients, as shown in Chronic Inflammatory Demyelinating Polyneuropathy.