Immunodetection of Helicobacter sp. and the associated expression of ABO blood group antigens in the gastric mucosa of captive and free-living New World primates in the Amazon region

The histo-blood group ABH antigens were first described in humans. These antigens are only present on erythrocytes from great apes and humans, while in more primitive animals they are found in tissues and body fluids. The ABH antigens are mainly distributed in tissues exposed to the external environment and potentially serve as ligands for pathogens or inhibitors of tissue connections. The objective of this paper was two-fold: (i) to determine the presence of Helicobacter sp. in the gastric mucosa of 16 captive and 24 free-living New World monkeys and (ii) to evaluate the presence of histopathological alterations related to bacterial infection and the associated expression of ABH antigens in the tissue. Stomach tissues from 13 species of monkey were assessed using haematoxylin-eosin and modified Gram staining (Hucker) methods. An immunohistochemical analysis of the tissue revealed the presence of infectious bacteria that were characteristic of the genus Helicobacter sp. The results demonstrate that various species of monkey might be naturally infected with the Helicobacter sp. and that there is an increased susceptibility to infection. This study serves as a comparative analysis of infection between human and non-human primates and indicates the presence of a new species of Helicobacter.

Seroconversion for west Nile and St. Louis encephalitis viruses among sentinel horses in Colombia

We prospectively sampled flavivirus-naïve horses in northern Colombia to detect West Nile virus (WNV) and St. Louis encephalitis virus (SLEV) seroconversion events, which would indicate the current circulation of these viruses. Overall, 331 (34.1%) of the 971 horses screened were positive for past infection with flaviviruses upon initial sampling in July 2006. During the 12-month study from July 2006-June 2007, 33 WNV seroconversions and 14 SLEV seroconversions were detected, most of which occurred in the department of Bolivar. The seroconversion rates of horses in Bolivar for the period of March-June 2007 reached 12.4% for WNV and 6.7% for SLEV. These results comprise the first serologic evidence of SLEV circulation in Colombia. None of the horses sampled developed symptoms of encephalitis within three years of initial sampling. Using seroconversions in sentinel horses, we demonstrated an active circulation of WNV and SLEV in northern Colombia, particularly in the department of Bolivar. The absence of WNV-attributed equine or human disease in Colombia and elsewhere in the Caribbean Basin remains a topic of debate and speculation.

Sentinel network for monitoring in vitro susceptibility of Plasmodium falciparum to antimalarial drugs in Colombia: a proof of concept

Drug resistance is one of the principal obstacles blocking worldwide malaria control. In Colombia, malaria remains a major public health concern and drug-resistant parasites have been reported. In vitro drug susceptibility assays are a useful tool for monitoring the emergence and spread of drug-resistant Plasmodium falciparum. The present study was conducted as a proof of concept for an antimalarial drug resistance surveillance network based on in vitro susceptibility testing in Colombia. Sentinel laboratories were set up in three malaria endemic areas. The enzyme linked immunosorbent assay-histidine rich protein 2 and schizont maturation methods were used to assess the susceptibility of fresh P. falciparum isolates to six antimalarial drugs. This study demonstrates that an antimalarial drug resistance surveillance network based on in vitro methods is feasible in the field with the participation of a research institute, local health institutions and universities. It could also serve as a model for a regional surveillance network. Preliminary susceptibility results showed widespread chloroquine resistance, which was consistent with previous reports for the Pacific region. However, high susceptibility to dihydroartemisinin and lumefantrine compounds, currently used for treatment in the country, was also reported. The implementation process identified critical points and opportunities for the improvement of network sustainability strategies.

The impact of CO2 on collection of Aedes aegypti (Linnaeus) and Culex quinquefasciatus Say by BG-Sentinel(r) traps in Manaus, Brazil

Carbon dioxide (CO2) is an important component for activating and attracting host-seeking mosquitoes. The BG-Sentinel(r) trap is a well-established monitoring tool for capturing Culicidae, but CO2 role for the trap effectiveness has not been evaluated in highly urbanised areas. The objective was to evaluate the effectiveness of BG-Sentinel traps baited with and without CO2 for capturing urban mosquitoes. Fifteen areas were selected within the city of Manaus, Brazil, where four BG-Sentinels were operated for 24 h, two of them with CO2 and two without CO2. Captured Aedes aegypti females were dissected for the determination of their parity status. A significantly higher proportion of traps (from 32-79%) were positive for female Ae. aegypti when using the BG-Sentinel with CO2 (χ2 = 11.0271, p ≤ 0.001). Catches of female Culex spp were six times higher in CO2 traps (Mann-Whitney U test = 190.5; p = 0.001). Parity rates were similar for both traps. This study showed that CO2 has primarily an enhancing effect on the efficacy of BG-Sentinel for capturing Culex spp in Manaus. For Ae. aegypti, the positivity rate of the trap was increased, when CO2 was added.

Using a top predator as a sentinel for environmental contamination with pathogenic bacteria: the Iberian wolf and leptospires

The Iberian wolf (Canis lupus) is the top predator in the Iberian environments in which it lives, feeding on a wide range of species, thus encountering a wide range of disease agents. Therefore, the wolf can serve as sentinel of environmental contamination with pathogens. We investigated the exposure of free-living wolves to 14 serovars of Leptospira interrogans sensu lato. Kidney samples from 49 wolves collected from 2010-2013 in northwestern Spain were analysed by culture, direct immunofluorescence and polymerase chain reaction. Tissue fluids were analysed for antibodies by a microscopic agglutination test. Ten wolves (observed prevalence: 20%, 95% confidence interval = 11-33%) showed evidence of contact with leptospires, eight through direct detection and nine through serology (7 wolves were positive according to both techniques). Titres below the cut-off level were also detected in seven cases. Serovars confirmed were Canicola (n = 4), Icterohaemorrhagiae (n = 3) and Sejroë, Ballum and Grippotyphosa (n = 1 each), indicating that wolves were infected with serovars for which dogs, rodents and ungulates, are the natural hosts and supporting the utility of the wolf and other large predators as environmental sentinels for pathogens.

Sentinel lymph node involvement and a high Breslow index are independent factors of risk for early relapse of melanoma

Rapport de synthèse : Le ganglion sentinelle (GS) se défini comme le premier ganglion de la chaîne ganglionnaire qui draine le territoire anatomique où siège une tumeur et, par conséquent, celui ayant le plus de possibilités de recevoir des métastases. La combinaison des deux techniques de détection du GS existantes, lymphoscintigraphie et coloration, permettent de déceler le GS dans 95-100% des cas. Le taux d'attente métastatique du GS varie entre 16 et 21 % des patients. Dans 50 à 87% des cas, le GS est le seul site de métastase et la probabilité de trouver des micro-métastases dans des ganglions appartenant aux relais supérieurs sans atteinte du GS est estimée à moins de 2%. Ces chiffres relèvent l'importance de la détection du GS. L'emploi de cette technique offre de nombreux avantages par rapport à la lymphadénéctomie élective que nous décrirons. Selon Rousseau et al., il existe une probable association entre le statut du GS et la survie de la maladie. Cette interprétation et celles d'autres auteurs soulignent la pertinence clinique du statut du GS dans le mélanome. En ce qui concerne la survie sans maladie (DFS) et la survie globale (OS), aucune différence significative n'a été observée entre les patients ayant subi une résection complète immédiate des ganglions lymphatiques et ceux qui d'abord ont subi une résection chirurgicale et analyse du GS secondaire, suivies par une dissection élective en cas de positivité. L'objectif de cette étude prospective était d'évaluer la pertinence de la positivité tumorale du GS dans l'évaluation des risques de rechute du mélanome. Cette étude a confirmé l'intérêt de la scintigraphie des ganglions lymphatiques (associée à la technique de coloration par bleu et celle de détection par sonde portable) dans l'identification du GS comme approche thérapeutique au stade précoce du mélanome. Elle a montré, en autre, que le statut du GS et l'indice de Breslow sont des facteurs de risque indépendants importants de rechute chez des patients atteints d'un mélanome au stade précoce. La combinaison de ces deux paramètres a permis de créer des groupes de patients à risque de rechute différents qui pourraient conduire à l'adaptation des protocoles de thérapie en fonction de ces risques.

Absence of ectopic epithelial inclusions in 3,904 axillary lymph nodes examined in sentinel technique.

Intraoperative examination of sentinel axillary lymph nodes can be done by imprint cytology, frozen section, or, most recently, by PCR-based amplification of a cytokeratin signal. Using this technique, benign epithelial inclusions, representing mammary tissue displaced along the milk line, will likely generate a positive PCR signal and lead to a false-positive diagnosis of metastatic disease. To better appreciate the incidence of ectopic epithelial inclusions in axillary lymph nodes, we have performed an autopsy study, examining on 100 μm step sections 3,904 lymph nodes obtained from 160 axillary dissections in 80 patients. The median number of lymph nodes per axilla was 23 (15, 6, and 1 in levels 1, 2, and 3, respectively). A total of 30,450 hematoxylin-eosin stained slides were examined, as well as 8,825 slides immunostained with pan-cytokeratin antibodies. Despite this meticulous work-up, not a single epithelial inclusion was found in this study, suggesting that the incidence of such inclusions is much lower than the assumed 5% reported in the literature.

Melanin-based colouration predicts aggressiveness and boldness in captive eastern Hermann's tortoises

Although body colouration is often used in social interactions, few studies have tested whether colouration is linked to a suite of behavioural traits. In the present study, we examined whether among captive adult male Eastern Hermann's tortoises (Eurotestudo boettgeri) behavioural patterns covary with eumelanic colouration of the shell. Dark eumelanic males were more aggressive in male-male confrontations and bolder towards humans. These relationships were independent of body size and ambient temperature. Activity level and exploration were not significantly associated with colouration. We conclude that at least in captivity shell colouration predicts agonistic behaviour towards conspecifics and fearfulness towards human (i.e. boldness).

Ganglion sentinelle dans les cancers du col de faible stade. Données actuelles. Assurance qualité. Perspectives [Sentinel lymph node in low stage cervical cancers. Current data. Quality assurance. Prospects].

Le prélèvement des ganglions sentinelles apparaît comme une technique séduisante pour l'évaluation ganglionnaire des cancers du col utérin de faible stade. La sélection d'une population à bas risque de métastase ganglionnaire, un entraînement minimal et le respect de quelques règles simples permettent de limiter le risque de faux négatif au minimum. La technique apporte des informations supplémentaires sur le plan anatomique en identifiant des ganglions situés en dehors des zones habituelles de curage, et sur le plan histologique avec la mise en évidence de cellules tumorales isolées et surtout de micrométastases dont la valeur pronostique est suspectée Sentinel node biopsy appears as a promising technique for the assessment of nodal disease in early cervical cancers. Selection of a population with a low risk of nodal metastasis, a minimal training, and simple rules allow a low false negative rate. Sentinel node biopsy provides supplementary information, such as anatomical information (nodes outside of routine lymphadenectomy areas) and histological information (isolated tumors cells and micrometastases).

Axillary Sentinel Lymph Node Biopsy for Breast Cancer and Melanoma Patients after Previous Axillary Surgery: A Systematic Review

Objective: Sentinel lymph node biopsy (SLNB) is a validated staging technique for breast carcinoma. Some women are exposed to have a second SLNB due to breast cancer recurrence or a second neoplasia (breast or other). Due to modi- fied anatomy, it has been claimed that previous axillary surgery represents a contra-indication to SLNB. Our objective was to analyse the literature to assess if a second SLNB is to be recommended or not. Methods: For the present study, we performed a review of all published data during the last 10 years on patients with previous axilla surgery and second SLNB. Results: Our analysis shows that second SLNB is feasible in 70%. Extra-axillary SNs rate (31%) was higher after radical lymph node dissection (ALND) (60% - 84%) than after SLNB alone (14% - 65%). Follow-up and com- plementary ALND following negative and positive second SLNB shows that it is a reliable procedure. Conclusion: The review of literature confirms that SLNB is feasible after previous axillary dissection. Triple technique for SN mapping is the best examination to highlight modified lymphatic anatomy and shows definitively where SLNB must be per- formed. Surgery may be more demanding as patients may have more frequently extra-axillary SN only, like internal mammary nodes. ALND can be avoided when second SLNB harvests negative SNs. These conclusions should however be taken with caution because of the heterogeneity of publications regarding SLNB and surgical technique.

Sentinel lymph node biopsy in nonmelanoma skin cancer patients.

The management of lymph nodes in nonmelanoma skin cancer patients is currently still debated. Merkel cell carcinoma (MCC), squamous cell carcinoma (SCC), pigmented epithelioid melanocytoma (PEM), and other rare skin neoplasms have a well-known risk to spread to regional lymph nodes. The use of sentinel lymph node biopsy (SLNB) could be a promising procedure to assess this risk in clinically N0 patients. Metastatic SNs have been observed in 4.5-28% SCC (according to risk factors), in 9-42% MCC, and in 14-57% PEM. We observed overall 30.8% positive SNs in 13 consecutive patients operated for high-risk nonmelanoma skin cancer between 2002 and 2011 in our institution. These high rates support recommendation to implement SLNB for nonmelanoma skin cancer especially for SCC patients. Completion lymph node dissection following positive SNs is also a matter of discussion especially in PEM. It must be remembered that a definitive survival benefit of SLNB in melanoma patients has not been proven yet. However, because of its low morbidity when compared to empiric elective lymph node dissection or radiation therapy of lymphatic basins, SLNB has allowed sparing a lot of morbidity and could therefore be used in nonmelanoma skin cancer patients, even though a significant impact on survival has not been demonstrated.

Intraoperative training on the techniques of sentinel node biopsy in breast cancer

Principles: Surgeon's experience is crucial for proper application of sentinel node biopsy (SNB) in patients with breast cancer. A 20-30 cases learning curve of sentinel node (SN) and axillary lymph node dissection (ALND) was widely practiced. In order to speed up this learning curve, surgeons may be trained intraoperative by an experienced surgeon. The purpose of this report is to evaluate the results of this procedure. Methods: Patients with one primary invasive breast cancer (cT1-T2[<3 cm]cN0) underwent SNB based on lymphoscintigraphy using technetium Tc 99m colloid, intraoperative gamma probe detection, with or without blue dye mapping. This was followed by completion ALND when SN was positive or not found. SNB was performed by one experienced surgeon (teacher) or by 10 junior surgeons trained by the experienced surgeon (trainees). Four groups were defined: (i) SNB with immediate ALND for the teacher's learning curve, (ii) SNB by the teacher, (iii) SNB by the trainees under the teacher's supervision, and (iv) SNB by the trainees alone. Results: Between May 1999 and December 2007, a total of 808 évaluable patients underwent SNB. The SN identification rate was 98% in the teacher's group, and 99% in the trainees' group (p = 0.196). SN were positive in respectively 28% and 29% of patients (p = 0.196). The distribution of isolated tumor cells, micrometastases and metastases was not statistically different between the teacher's and the trainees' groups (p = 0.163). Conclusion: These comparable results confirm the success with which the SNB was taught. This strategy avoided the 20-30 SNB followed by immediate ALND early required per surgeon.

Morbidity and outcome after sentinel lymph node dissection in patients with early-stage malignant cutaneous melanoma.

OBJECTIVE: Prospective analysis of the morbidity and outcome of the sentinel lymph node (SLN) technique in a consecutive series of patients with early-stage melanoma. METHODS: Between 1997 and 1998, 60 patients with stage IB-II malignant melanoma underwent SLN dissection. Preoperative dynamic lymphoscintigraphy with mapping of the lymph vessels and lymph nodes and location of the sentinel node was performed the day before SLN dissection. SLN was identified by use of the blue dye technique. SLN was assessed for histopathological and immunohistochemical examination. Postoperative morbidity and mortality were recorded. Follow-up consisted of repetitive clinical examination with lymph nodes status, laboratory and radiologic findings. RESULTS: Tumor-positive SLN was observed in 18% of the patients and stage II disease was found in 91% of the patients with positive SLN. Breslow thickness was the only significant factor predicting involvement of a SLN (p = 0.02). In 36% of the positive SLN, metastases could be assessed only by immunohistochemical examination. Postoperative complications after SLN dissection were observed in 5% in comparison with 36% after elective lymph node dissection. After a mean follow-up of 32 months, recurrence was observed in 3% with a mean disease-free survival of 8 months. Overall survival was 82% and 90% in patients with positive and negative SLN, respectively. Overall mortality was 15%, due to distant metastases in 78% of the cases. CONCLUSIONS: Staging of early-stage melanoma with the SLN dissection by use of the blue dye technique combined to lymphoscintigraphy and immunohistochemistry is reliable and safe, with less morbidity than elective lymphadenectomy. Long-term follow-up is mandatory to establish the exact reliability of SLN dissection.