Experimental infection of bed bugs (Cimex lectularius L.) with Burkholderia multivorans.

The bacterium Burkholderia multivorans is an opportunistic nosocomial pathogen of humans. A previous study reported molecular detection of this bacterium in several specimens of the common bed bug (Cimex lectularius L.) collected from an elderly care facility in the U.S.A., raising questions about the possibility of vector-borne transmission. However, the ability of B. multivorans to colonize bed bugs and the ability of bed bugs to transmit the bacteria both remained untested. To resolve this knowledge gap, here we performed a set of experiments to examine the persistence and shedding of B. multivorans following ingestion by bed bugs in a blood meal. We isolated viable B. multivorans from the bodies of bed bugs for up to 13 days post-ingestion, but bacterial load substantially diminished over time. By 16 days post-ingestion, the bacteria could not be isolated. Further, B. multivorans was not shed in the saliva of infected bugs during feeding nor was it transmitted vertically from infected insects to their progeny. Based on these results, significant biological or mechanical transmission of B. multivorans to humans by bed bugs appears unlikely. Nonetheless, some viable bacteria were passively shed into the environment through defecation, a process which could potentially contribute to transmission through indirect contamination under rare circumstances.

[Suffering at work among medical students: qualitative study using semi-structured interviews]. / Souffrance au travail des étudiants en médecine : étude qualitative par entretiens semi-dirigés.

INTRODUCTION: Suffering at work among health professionals is a hot topic. Medical students, doctors of tomorrow, are far from being spared. Prevalence of anxiety and mood disorders range from 20.3 to 69 % for the former and from 12 to 30 % for the latter. The purpose of this article is to determine these factors by qualitative research, according to medical students' points of view. METHODS: It is a qualitative study using semistructured interviews. The analysis is done according to the Grounded Theory. RESULTS: 12 medical students are interviewed. They expressed difficulties at work and positive factors. Three major themes are identified in selective coding: occupational factors, " study " factors and individual factors. All themes are both a source of well-being and ill-being according to the situations specified in the results. CONCLUSION: Studying medicine includes positive and negative aspects. Abandonment issues, lack of recognition and insufficient coaching emerge from our study. Screening of suffering at work should be systematic for medical students.

INTRODUCTION: La souffrance au travail chez les professionnels de santé est un sujet d'actualité. Les étudiants en médecine, médecins de demain, sont loin d'être épargnés. Ils présentent notamment des troubles anxieux et de l'humeur dont les prévalences s'échelonnent de 20,3 à 69 % pour les premiers et de 12 à 30 % pour les seconds. Cette étude a pour objectif de déterminer ce qui est ressenti comme positif ou négatif au travail du point de vue des étudiants hospitaliers. Matériel et méthode : Il s'agit d'une étude qualitative par entretiens semi-dirigés. L'analyse se fait selon une thématisation progressive en suivant la Grounded Theory, ou théorisation ancrée, méthode issue des sciences sociales, visant à élaborer une théorie des représentations, non à partir d'hypothèses prédéterminées, mais à partir de données de terrain recueillies par entretiens. Résultats : La variation est maximale. La saturation des données a été atteinte avec 12 sujets. Ceux-ci ont exprimé des difficultés au travail mais aussi des facteurs de ressenti positif. Trois grands thèmes ont été définis en codage sélectif : les facteurs professionnels, les facteurs " étude " et les facteurs individuels. Quelle que soit la thématique abordée, les relations avec le ressenti du travail sont à la fois source d'épanouissement et de souffrance selon les situations précisées dans les résultats. CONCLUSION: Le vécu des études médicales comprend des aspects positifs et négatifs. Les problématiques de délaissement, de manque de reconnaissance ou encore d'accompagnement insuffisant ressortent de notre étude. Ceci ouvre des pistes de prévention. Le dépistage d'un malêtre au travail devrait être systématique chez ces étudiants.

Knockdown of mitogen-activated protein kinase (MAPK) signalling in the midgut of Anopheles stephensi mosquitoes using antisense morpholinos.

Arthropod-borne infectious diseases are responsible for nearly 1.5 million deaths annually across the globe, with malaria responsible for >50% of these deaths. Recent efforts to enhance malaria control have focused on developing genetically modified Anopheles mosquitoes that are resistant to malaria parasite infection by manipulating proteins that are essential to the immune response. Although this approach has shown promise, the lack of efficient genetic tools in the mosquito makes it difficult to investigate innate immunity using reverse genetics. Current gene knockdown strategies based on small interfering RNA are typically labourious, inefficient, and require extensive training. In the present study, we describe the use of morpholino antisense oligomers to knockdown MEK-ERK signalling in the midgut of Anopheles stephensi through a simple feeding protocol. Anti-MEK morpholino provided in a saline meal was readily ingested by female mosquitoes with minimal toxicity and resulted in knockdown of total MEK protein levels 3-4 days after morpholino feeding. Further, anti-MEK morpholino feeding attenuated inducible phosphorylation of the downstream kinase ERK and, as predicted by previous work, reduced parasite burden in mosquitoes infected with Plasmodium falciparum. To our knowledge, this is the first example of morpholino use for target protein knockdown via feeding in an insect vector. Our results suggest this method is not only efficient for studies of individual proteins, but also for studies of phenotypic control by complex cell signalling networks. As such, our protocol is an effective alternative to current methods for gene knockdown in arthropods.

Molecular detection of Rickettsia infection in field-collected bed bugs.

Bed bugs are now one of the most prevalent human-associated, blood-feeding pests in the urban world, but few studies of their association with human pathogens have been conducted since their resurgence. Here, we used PCR to screen samples of field-collected bed bugs (Cimex spp.) for the presence of Rickettsia bacteria and we describe the first detection of an uncharacterized Rickettsia in Cimex lectularius in nature. Rickettsia was detected in 5/39 (12.8%) of the bed bug samples tested. In particular, three pools from the USA and two individual insects from the UK were positive for Rickettsia DNA. Sequencing and analysis of a fragment of the citrate synthase gene (gltA) from positive samples from each country revealed that the Rickettsia detected in both were identical and were closely related to a Rickettsia previously detected in the rat flea Nosopsyllus laeviceps. Additional experiments indicated that the Rickettsia localizes to multiple tissues in the bed bug and reaches high titres. Attempts were made to infect mammalian cells in culture but these efforts were inconclusive. Our findings suggest that Rickettsia are secondary endosymbionts of bed bugs and have potential implications for both bed bug control and public health. However, further investigation is required to determine the pathogenicity of this Rickettsia, its transmission mechanisms, and its contributions to bed bug physiology.

[Returning to work after an acute coronary syndrome: When waiting is wasting]. / Retour au travail après un accident coronarien aigu.

BACKGROUND: Return to work (RTW) after acute coronary syndrome (ACS) is an important issue for the patient's future. AIMS: The study aim was to determine whether RTW practice complies with guidelines or is delayed by failure in patient management. We analysed the factors influencing RTW beyond the 90-day period recommended by guidelines. METHODS: We conducted a survey of 216 self-employed workers admitted to the hospital for ACS using self-report questionnaires and medical examination. Factors influencing RTW, occupational and cardiac features, and recall and source of medical information were investigated. RESULTS: Ninety-three of 216 patients did not return to work by 90 days, despite good cardiac performance in 30 cases (32 %). The mean sick leave duration was 93.3±103.7 days. Advice concerning return to work was completely missing for 44 % of patients. Cardiac performance was independent of sick leave duration, but was correlated with the likelihood of RTW (P<0.001). Patients assimilated about 70 % of the medical information they were provided, but only 53 % of work-related information. Recall of work-related information was better among patients admitted to a rehabilitation facility (65 %) compared to those who did not receive rehabilitation (P<0.05). CONCLUSION: Cardiologists should assess the patient's cardiac performance within 2 months after ACS. Patient management should also include cardiac rehabilitation or therapeutic education toward improving information recall.

Aortoseptal approach for optimal resection of diffuse subvalvular aortic stenosis.

The results of conventional operative resection of diffuse subaortic stenosis (tunnel subaortic stenosis and diffuse idiopathic hypertrophic subaortic stenosis) have been less than satisfactory. A new approach using the concept of aortoventriculoplasty was designed to allow adequate surgical resection of a diffuse subvalvular aortic stenosis. The aorta, the right ventricle, and the septum are incised in the same way as during aortoventriculoplasty , with the aortic anulus being divided carefully across the commissure between the left and right aortic cusps. The septotomy is extended beyond the limits of the stenosis, and fibrous and/or muscular tissue is removed from each edge of the septal incision. After adequate widening of the subvalvular area, the various incisions are closed and the aortic valve is reconstructed. This aortoseptal approach was studied experimentally in the dog and then carried out on two patients, both of whom had excellent hemodynamic and functional results. The aortoseptal approach may be the procedure of choice in the treatment of diffuse stenoses limited to the subvalvular area, whereas other procedures ( aortoventriculoplasty , and apico-aortic valved conduit) should be used when the valvular and/or supravalvular levels are involved.

Transvenous interruption of the inferior vena cava. New model of vena cava filter. Preliminary results in 35 cases.

Partial interruption of inferior vena cava (I.C.V.) forms an integral part of treatment of thromboembolic disease. The most frequently used filter worldwide is currently that of Greenfield, but although its effectiveness and permeability are remarkable it can be the subject of transfixions, sliding movements and migrations. A new model of the authors' own conception is presented which eliminates these faults. The "2612" filter is based on the same concepts, but has added to it 6 lateral flanges soldered to the base of the arms, these applying pressure to the I.V.C. and ensuring its perfect positioning, and 12 hooks (6 turned downwards and 6 upwards) ensuring perfect stability. Results of a multicentre trial in 35 patients, after insertion of the "2612" filter and follow-up assessment after 3 months (28 cases) by cavography and in some patients by a scan, showed permeability of 93% and total efficacy. No side effects were reported. This filter appears to represent true progress in the means of interrupting I.V.C., and further studies are contemplated.

[False aneurysms in prostheses of the aortic bifurcation. Apropos of 34 case reports]. / Les faux anévrysmes sur prothèses du carrefour aortique. A propos de 34 observations.

Thrombosis, infection, false aneurysm and hemorrhage are all complications occurring following reconstructive arterial surgery. The authors study what is certainly the most unusual of these complications, i. e. development of false aneurysms of prostheses of the aortic bifurcation. They describe the various etiological factors responsible for their onset and also new diagnostic features and the principles of re-operation as well as results. This study is based upon a series of 34 cases of false aneurysm of prostheses of the aortic bifurcation inserted over a ten year period from 1974 to 1984. During this period, 1,400 prostheses of aortic bifurcation were inserted, essentially for two indications: chronic obliterative arterial disease of the lower limbs and aneurysmal disease. The mean latent period of onset of the complication was four and a half years. Removal followed by insertion of a new prosthetic graft is the basic treatment, overall mortality being 4% and morbidity being 30%, dominated by secondary thrombosis in 19% of cases, local infection in 8% of cases and recurrence of aneurysm in the same percentage of individuals. The overall figure of very good results was 70%. Whilst discussion is dominated by the role of different etiological factors, it nevertheless remains important to note that only progress in prosthetic and suture materials can allow a future decrease in the percentage of such false aneurysms, the factor inherent in the vascular surgeon, i. e. operative technique itself, being much easier to deal with on principle. This complication nevertheless remains very serious, best dealt with by surgery since the natural history of this false aneurysm is completely different from that of a classical femoral or popliteal aneurysm.

[Double subclavian and vertebral reimplantation into the common carotid artery using single anastomosis]. / Double réimplantation sous-clavière et vertébrale dans la carotide primitive avec une seule anastomose.

A variant of the technique used for implantation of subclavian artery into common carotid artery is proposed with the aim of improving vertebral blood flow, particularly in cases with combined foraminal vertebral and subclavian artery lesions.

[So-called "primary" infected aneurysms of the sub-renal abdominal aorta. Five observations]. / Les anévrismes infectieux dits "primitifs" de l'aorte abdominale sous-rénale. A propos de cinq observations.

The authors describe 5 cases of mycotic aneurysms of the infrarenal abdominal aorta. These relatively rare lesions raise problems which are not so much diagnostic but above all therapeutic and etiopathogenic. They are rare lesions, with a striking clinical picture and often very spectacular radiological appearances, in particular by CT scan and angiography. Indications for surgery as well as the technique used thus comply with rigorous norms. However, despite everything, and in particular despite increasingly early positive diagnosis, rapid surgical management and advances in vascular surgery techniques, the mortality associated with such lesions remains very high, even in the context of cold aneurysm surgery, when compared with ordinary atherosclerotic aneurysms, dealt with under the same conditions.

[Portal and superior mesenteric venous thrombosis secondary to oral contraceptive treatment. Two cases (author's transl)]. / Thromboses veineuses portale et mésentérique supérieure, secondaires a un traitement contraceptif oral. A propos de deux cas.

Two new cases of superior mesenteric, portal and pulmonary venous thrombosis enable the authors to stress the close link between this pathology and the ingestion of oral contraceptives. The resultant vessel wall changes and laboratory changes are described. Whilst complete normalisation at the end of treatment is confirmed, preventive treatment will soon be possible by virtue of the development of new natural substances already perfected in the United States and the Scandinavian countries and recently marketed in our own country.

PIP: About 28% of women aged 15-44 use oral contraceptives (OCs) in France. The 2 cases presented here, of superior mesenteric portal and pulmonary venous thrombosis in patients on uninterrupted OCs for 8 years, reconfirm the association between OCs and embolic pathology. Similar cases have been often described in the published literature. 3 main factors influence the induction of such thromboses; 1) modification of blood coagulation, 2) modification of the vessels' walls, and, 3) immunologic role of OCs. Blood coagulation is apparently modified by synthetic estrogens only, and not be progestin agents. The vessels' walls undergo a gradual thickening, together with a proliferation of the smooth muscular cells. On the immunologic plan, it is possible that OCs may cause the procreation of antiethinyl-estradiol antibodies which appear as circulating immune complexes. Thromboembolic risk disappears spontaneously after termination of OC treatment.

[The indications for lumbar sympathectomy as a function of clinical findings and of the results of the angiographic test]. / Les indications de la sympathectomie lombaire en fonction de la clinique et du résultat de l'examen angiographique.

Indications for lumbar sympathectomy are presented as a function of the clinical findings and results of angiography, voluntarily ignoring data from non-invasive vascular function tests, in an attempt to answer two questions. Firstly, can the decision to perform lumbar sympathectomy depend on clinical findings only in 1983? Secondly, is angiography essential in all cases before sympathectomy? The positive response to both questions is based on a study of approximately 2,300 case reports.

[Thrombectomy in secondary and/or late thrombosis of branches of the aortic bifurcation prosthesis]. / Thrombectomie pour thrombose secondaire et/ou tardive des branches de prothèse du carrefour aortique.

Between 1974 and 1984, 1,100 prostheses of the aortic bifurcation, aorto-bi-femoral or aorto-bi-iliac, were inserted for atherosclerotic lesions: aneurysms were excluded from this analysis. The most frequently used prosthesis material was of double velvet Dacron. Global percent thrombosis development was 5.5%. Possible causes of the thrombosis are the operative techniques, the distal arterial bed and the presence or absence of associated anticoagulant therapy. Techniques used and results obtained with thrombectomy on one or more thrombosed prosthesis branches are compared with other reconstructive procedures for similar indications, particularly atypical axillo-femoral or inter-femoral by-pass operations. Results of this comparison may appear surprising but are nevertheless perfectly logical.

[Evaluation of the neurological risk of asymptomatic carotid stenosis and discussion of the value of carotid surgery in stage 0. Apropos of a study of 123 obliterative lesions]. / Evaluation du risque neurologique d'une sténose carotidienne asymptomatique et discussion de l'intérêt de la chirurgie carotidienne au stade 0. A propos de l'étude de 123 lésions oblitérantes.

The authors analyzed neurological risk on the basis of the study of 123 asymptomatic obstructive carotid lesions. Patients were divided into two groups: Group A (54 patients undergoing prophylactic endarterectomy). Group B (69 patients not undergoing surgery). Definition of the carotid lesion was based upon a combination of Doppler, sonography and arteriography results. Assessment of comparative neurological risk, on the basis of a hemodynamic definition of the stenosis, in the two patient groups, led to definition of appropriate management of an asymptomatic carotid stenosis. In group A, operative mortality was nil and there was one transient ischemic accident. In group B, there were 12 accidents, 9 transient and 3 permanent. In this latter group there was one neurological death, i. e. mortality of neurological origin of 1.5%. Evaluation of risk initially requires definition of the stenosis. The presence of a carotid bruit alone is inadequate. Doppler and sonography, followed where necessary by arteriography, define the degree of stenosis which is the primordial prognostic feature. The difference of risk between a population undergoing surgery or not is statistically significant, in particular in hemodynamically tight stenosis. Finally, the degree of stenosis influences the severity of any subsequent accident, although this has not been proved statistically. In the majority of cases, the initial accident would appear to be regressive. In total, 4 concepts have been defined: the risk of carotid surgery at stage 0 is low, being of the order of 0. Overall neurological risk is less in the long term in asymptomatic patients who have undergone surgery than in those who have not been operated upon.(ABSTRACT TRUNCATED AT 250 WORDS)

[Superior vena cava syndrome and Riedel's thyroiditis. Report of a case: review of the literature]. / Syndrome cave supérieur et thyroidite de Riedel. A propos d'un cas: revue de la littérature.

The authors present the case of a 42-year-old female patient, initially admitted to hospital for the etiological diagnosis--which remained negative--and the treatment of a superior vena cava syndrome. This patient was seen again two years later as the superior vena cava syndrome recurred, while a thyroid syndrome appeared at the same time. Exeresis followed by a clinicopathological study demonstrated Riedel's chronic fibrous thyroiditis. The authors study the causal relationships between both conditions and their integration into multifocal fibroses. To their knowledge, this is the first case in which the superior vena caval syndrome is the site of occurrence of fibrosis, precedes the thyroid involvement. The new radiological technique at our disposal--CT, MRI--should allow more easily searching for the various sites of the fibrosing disease (biliary ducts, pancreas, duodenum, retroperitoneum, mediastinum, orbits), and immunological studies will make it possible to better classify them and define their pathogenesis.

[Leg ulcers in Werner's syndrome. Report of one case]. / Les ulcères de jambe du syndrome de Werner. A propos d'un cas.

Werner's syndrome (adult progeria) is a rare autosomal recessive condition characterized mainly by a characteristic habitus (short stature, light body weight) scleroderma like changes of the limbs and premature aging. Chronic leg ulcers appears in about fifty per cent of the patients. These ulcers can be related to the combination of mechanical factors on atrophic subcutaneous tissue and skin of the feet and leg associated with early arteriosclerosis (20%) and diabetes mellitus (60%).

[Value of velocimetric and echotomographic examination in monitoring central catheterizations]. / Intérêt de l'examen vélocimétrique et échotomographique dans la surveillance des cathétérismes centraux.

Thrombosis around a centrally-implanted catheter is a complication of this method of venous approach. Usually asymptomatic, it is normally detected by phlebography, histopathology or computed angiotomography. Thirty-five patients with catheters in internal jugular vein composed of silicone (13 cases) or polyurethane (22 cases) were followed up by velocimetric and echotomographic examinations before introduction and one and three weeks after introduction of a catheter, these exploratory procedures possessing the advantage of being rapid, repetable and non-invasive. Three thrombosis were diagnosed using this method, including two without clinical signs, one on a silicone and two a polyurethane catheter. This represents 8.6% of total population, comparable with results of phlebography and histopathology reported in the litterature. The echotomographic appearance of the fibrinoplatelet sleeve left by the catheter after its removal is also described. Combined velocimetric and echotomographic examination is an investigational method which is non-invasive, reliable, rapid and repeatable for evaluation of appearance, localization, extension and also follow up of thrombosis.

[Partial interruption of the inferior vena cava using the 2612 filter. Apropos of 35 patients]. / Interruption partielle de la veine cave inférieure (I.P.V.C.I.) par le filtre "2612". A propos de 35 patients.

Partial interruption of inferior vena cava (I.C.V.) forms an integral part of treatment of thromboembolic disease. The most frequently used filter worldwide is currently that of Greenfield, but although its effectiveness and permeability are remarkable it can be the subject of transfixions, sliding movements and migrations. A new model of the authors' own conception is presented which eliminates these faults. The "2612" filter is based on the same concepts, but has added to it 6 lateral flanges soldered to the base of the arms, these applying pressure to the I.V.C. and ensuring its perfect positioning, and 12 hooks (6 turned downwards and 6 upwards) ensuring perfect stability. Results of a multicentre trial in 35 patients, after insertion of the "2612" filter and follow up assessment after 3 months (28 cases) by cavography and in some patients by a scan, showed permeability of 93% and total efficacy. No side effects were reported. This filter appears to represent true progress in the means of interrupting I.V.C., and further studies are contemplated.

[Vascular complications of cervical ribs. Apropos of 15 cases]. / Les complications vasculaires des côtes cervicales. A propos de 15 observations.

Anatomical, etiopathogenic, clinical, and paraclinical aspects of vascular complication of cervical rib are discussed based on findings in 15 cases. Emphasis is placed on the value of newly available non-invasive functional tests, such as computerized angiography and particularly ultrasonography, which can modify surgical conduct. Operative technique is described, and indications for surgery and short- and long-term results obtained presented. Evaluation of results reported in the literature shows that they were excellent in 75 to 93% of cases, recent studies indicating an even higher rate of improvement.

[Effect of meteorological variations on the emergence of deep venous thrombosis of the leg]. / Influence des variations météorologiques sur la survenue de thrombose veineuse profonde des membres inférieurs.

INTRODUCTION: Recent articles have established a significant relationship between metereology variables and the development of vascular disease. We performed a retrospective study to determine relationships between the development of deep vein thrombosis in the lower limb and certain meteorology variables. MATERIALS AND METHODS: We identified 345 cases of phlebitis in 1995. We studied the distribution of the number of venous thrombosis per day, per month and per season. We compared certain meteorological data (atmospheric pressure, temperature, mean hygrometery) for days with and days without venous thrombosis and the atmospheric variations during the 48 hours prior to venous thrombosis. RESULTS: There was a significant relationship (p < 0.004) between the mean number of cases of phlebitis recorded per day and season with winter predominating. On days when phlebitis occurred, the atmospheric pressure was significantly lower (p < 0.05). The number of thrombotic events was significantly different on days when the variation was greater than 10 hectopascals than on days when the variation was less than 10 hectopascals (p < 0.05). CONCLUSIONS: In our study, deep vein thrombosis of the lower limb was significantly associated with certain meteorology variables. Prospective multicentric studies are needed to confirm these relationships.