Guidelines of the French Society of Otorhinolaryngology-Head and Neck Surgery (SFORL), part I: Primary treatment of pleomorphic adenoma

INTRODUCTION

The authors present the guidelines of the French Society of Otorhinolaryngology-Head and Neck Surgery (SFORL) for the diagnosis and treatment of pleomorphic adenoma (PA) of the salivary glands.

METHOD

A review of the literature was performed by a multidisciplinary task force. Guidelines were drafted based on the articles retrieved and the workgroup members' individual experience. Guidelines were graded A, B, C or expert opinion by decreasing level of evidence.

RESULTS

In clinically suspected salivary gland PA, MRI should be performed, including head and neck lymph node levels. Fine needle aspiration cytology is particularly recommended for tumours difficult to characterise by MRI. Frozen section biopsy should be performed to confirm diagnosis and adapt the surgical procedure in case of intraoperative findings of malignancy. Complete resection of the parotid PA should be performed en bloc, including margins, when feasible according to tumour location, while respecting the facial nerve. Enucleation (resection only in contact with the tumour) is not recommended. For the accessory salivary and submandibular glands, complete en bloc resection should be performed.

Basal Ti level in the human placenta and meconium and evidence of a materno-foetal transfer of food-grade TiO2 nanoparticles in an ex vivo placental perfusion model

Background

Titanium dioxide (TiO₂) is broadly used in common consumer goods, including as a food additive (E171 in Europe) for colouring and opacifying properties. The E171 additive contains TiO₂ nanoparticles (NPs), part of them being absorbed in the intestine and accumulated in several systemic organs. Exposure to TiO₂-NPs in rodents during pregnancy resulted in alteration of placental functions and a materno-foetal transfer of NPs, both with toxic effects on the foetus. However, no human data are available for pregnant women exposed to food-grade TiO₂-NPs and their potential transfer to the foetus. In this study, human placentae collected at term from normal pregnancies and meconium (the first stool of newborns) from unpaired mothers/children were analysed using inductively coupled plasma mass spectrometry (ICP-MS) and scanning transmission electron microscopy (STEM) coupled to energy-dispersive X-ray (EDX) spectroscopy for their titanium (Ti) contents and for analysis of TiO₂ particle deposition, respectively. Using an ex vivo placenta perfusion model, we also assessed the transplacental passage of food-grade TiO₂ particles.

Results

By ICP-MS analysis, we evidenced the presence of Ti in all placentae (basal level ranging from 0.01 to 0.48 mg/kg of tissue) and in 50% of the meconium samples (0.02–1.50 mg/kg), suggesting a materno-foetal passage of Ti. STEM-EDX observation of the placental tissues confirmed the presence of TiO₂-NPs in addition to iron (Fe), tin (Sn), aluminium (Al) and silicon (Si) as mixed or isolated particle deposits. TiO₂ particles, as well as Si, Al, Fe and zinc (Zn) particles were also recovered in the meconium. In placenta perfusion experiments, confocal imaging and SEM-EDX analysis of foetal exudate confirmed a low transfer of food-grade TiO₂ particles to the foetal side, which was barely quantifiable by ICP-MS. Diameter measurements showed that 70 to 100% of the TiO₂ particles recovered in the foetal exudate were nanosized.

Conclusions

Altogether, these results show a materno-foetal transfer of TiO₂ particles during pregnancy, with food-grade TiO₂ as a potential source for foetal exposure to NPs. These data emphasize the need for risk assessment of chronic exposure to TiO₂-NPs during pregnancy.

Guidelines of the French Society of Otorhinolaryngology-Head and Neck Surgery (SFORL), part II: Management of recurrent pleomorphic adenoma of the parotid gland

INTRODUCTION

The authors present the guidelines of the French Society of Otorhinolaryngology-Head and Neck Surgery (SFORL) for the management of recurrent pleomorphic adenoma (RPA) of the parotid gland.

METHOD

A review of the literature was performed by a multidisciplinary task force. Guidelines were drafted, based on the articles retrieved and the work group members' individual experience. There were then read and re-edited by an independent reading group. The proposed recommendations were graded A, B or C on decreasing levels of evidence.

RESULTS

Complete resection under neuromonitoring is recommended in case of RPA. The risks of progression and malignant transformation, which are higher the younger the patient, have to be taken into consideration. The risk of functional sequelae must be explained to the patient. MRI is recommended ahead of any surgery for parotid RPA, to determine extension and detect subclinical lesions. Radiotherapy should be considered in case of multi-recurrent pleomorphic adenoma after macroscopically complete revision surgery at high risk of new recurrence (microscopic residual disease), in case of RPA after incomplete resection, and in non-operable RPA.

Correlation between work impairment, scores of rhinitis severity and asthma using the MASK-air® App

BACKGROUND

In allergic rhinitis, a relevant outcome providing information on the effectiveness of interventions is needed. In MASK-air (Mobile Airways Sentinel Network), a visual analogue scale (VAS) for work is used as a relevant outcome. This study aimed to assess the performance of the work VAS work by comparing VAS work with other VAS measurements and symptom-medication scores obtained concurrently.

METHODS

All consecutive MASK-air users in 23 countries from 1 June 2016 to 31 October 2018 were included (14 189 users; 205 904 days). Geolocalized users self-assessed daily symptom control using the touchscreen functionality on their smart phone to click on VAS scores (ranging from 0 to 100) for overall symptoms (global), nose, eyes, asthma and work. Two symptom-medication scores were used: the modified EAACI CSMS score and the MASK control score for rhinitis. To assess data quality, the intra-individual response variability (IRV) index was calculated.

RESULTS

A strong correlation was observed between VAS work and other VAS. The highest levels for correlation with VAS work and variance explained in VAS work were found with VAS global, followed by VAS nose, eye and asthma. In comparison with VAS global, the mCSMS and MASK control score showed a lower correlation with VAS work. Results are unlikely to be explained by a low quality of data arising from repeated VAS measures.

CONCLUSIONS

VAS work correlates with other outcomes (VAS global, nose, eye and asthma) but less well with a symptom-medication score. VAS work should be considered as a potentially useful AR outcome in intervention studies.

Daily allergic multimorbidity in rhinitis using mobile technology: A novel concept of the MASK study

BACKGROUND

Multimorbidity in allergic airway diseases is well known, but no data exist about the daily dynamics of symptoms and their impact on work. To better understand this, we aimed to assess the presence and control of daily allergic multimorbidity (asthma, conjunctivitis, rhinitis) and its impact on work productivity using a mobile technology, the Allergy Diary.

METHODS

We undertook a 1-year prospective observational study in which 4 210 users and 32 585 days were monitored in 19 countries. Five visual analogue scales (VAS) assessed the daily burden of the disease (i.e., global evaluation, nose, eyes, asthma and work). Visual analogue scale levels <20/100 were categorized as "Low" burden and VAS levels ≥50/100 as "High" burden.

RESULTS

Visual analogue scales global measured levels assessing the global control of the allergic disease were significantly associated with allergic multimorbidity. Eight hypothesis-driven patterns were defined based on "Low" and "High" VAS levels. There were <0.2% days of Rhinitis Low and Asthma High or Conjunctivitis High patterns. There were 5.9% days with a Rhinitis High-Asthma Low pattern. There were 1.7% days with a Rhinitis High-Asthma High-Conjunctivitis Low pattern. A novel Rhinitis High-Asthma High-Conjunctivitis High pattern was identified in 2.9% days and had the greatest impact on uncontrolled VAS global measured and impaired work productivity. Work productivity was significantly correlated with VAS global measured levels.

CONCLUSIONS

In a novel approach examining daily symptoms with mobile technology, we found considerable intra-individual variability of allergic multimorbidity including a previously unrecognized extreme pattern of uncontrolled multimorbidity.

Transfer of innovation on allergic rhinitis and asthma multimorbidity in the elderly (MACVIA-ARIA) - EIP on AHA Twinning Reference Site (GARD research demonstration project)

The overarching goals of the European Innovation Partnership on Active and Healthy Ageing (EIP on AHA) are to enable European citizens to lead healthy, active and independent lives whilst ageing. The EIP on AHA includes 74 Reference Sites. The aim of this study was to transfer innovation from an app developed by the MACVIA-France EIP on AHA reference site (Allergy Diary) to other reference sites. The phenotypic characteristics of rhinitis and asthma multimorbidity in adults and the elderly will be compared using validated information and communication technology (ICT) tools (i.e. the Allergy Diary and CARAT: Control of Allergic Rhinitis and Asthma Test) in 22 Reference Sites or regions across Europe. This will improve the understanding, assessment of burden, diagnosis and management of rhinitis in the elderly by comparison with an adult population. Specific objectives will be: (i) to assess the percentage of adults and elderly who are able to use the Allergy Diary, (ii) to study the phenotypic characteristics and treatment over a 1-year period of rhinitis and asthma multimorbidity at baseline (cross-sectional study) and (iii) to follow-up using visual analogue scale (VAS). This part of the study may provide some insight into the differences between the elderly and adults in terms of response to treatment and practice. Finally (iv) work productivity will be examined in adults.

Interest of video-assisted minimally invasive surgery in primary hyperparathyroidism

INTRODUCTION

Surgery is the only radical and definitive treatment for primary hyperparathyroidism. Exploration of the four parathyroid sites is giving way to minimally invasive techniques. The present study sought to compare two minimally invasive parathyroidectomy techniques, by classical cervicotomy (MIP-C) and by video-assistance (MIP-VA), in terms of success rate, complications rate, operating time, and patient and community physician satisfaction.

MATERIALS AND METHOD

A non-randomized retrospective comparative study included 112 patients presenting with primary hyperparathyroidism with identified parathyroid adenoma, operated on between January 2005 and October 2010. The two groups were constituted according to the surgeons' habitual practice: 54 cases of MIP-VA and 58 of MIP-C.

RESULTS

Results for MIP-VA and MIP-C were respectively: success, 96.3% vs. 100% (P=0.09); mean scar size, 1.47 vs. 3.43cm (P<0.01); hypocalcemia, 2 vs. 3 cases (P=0.1); theater time, 94.25 vs. 76min (P=0.02); and postoperative stay, 1.08 vs. 1.37 days (P=0.07). Patient satisfaction was comparable between groups, while 93.3% of community physicians found MIP-VA preferable to MIP-C, although only 39.3% had known the MIP-VA technique.

CONCLUSION

With efficacy, morbidity and patient satisfaction comparable to classical surgery, MIP-VA significantly reduced cervicotomy size and hospital stay. Community physicians considered it to be preferable to MIP-C.

Nodular recurrence and hypothyroidism following partial thyroidectomy for benign nodular thyroid disease in children and adolescents

OBJECTIVES

Diagnostic and therapeutic processing of a thyroid nodule in children and adolescents may require lobectomy-isthmusectomy (LI) or nodule-resection (NR). Very few data in the literature report the long-term evolution of the remaining thyroid lobe in a defined pediatric population. In this study, we aimed to answer the following questions: Does a nodule recurrence occur in the remainder lobe? Is a post-operative thyroxine treatment necessary?

MATERIAL AND METHODS

This retrospective study describes 28 patients under 18 who underwent LI (22 cases) or NR (6 cases) from January 2004 to March 2012. Ten of them were lost to follow up, 18 could be assessed (4 NR (22%) and 14 LI (78%) - mean follow-up 45±31 months). All patients benefited of post-operative thyroid ultrasonography, and regular endocrinologic follow-up. The following data were analysed: emergence of new thyroid nodules, evolution of pre-existing nodules, occurrence of post-operative hypothyroidism and requirement for completion thyroidectomy.

RESULTS

The mean age at the time of surgery was 14.3±1.9 years. Two patients (11%) had pre-existing nodules in the remaining thyroid gland, none of which showed an increase in size after surgery. De novo nodules developed in five patients (27.8%). Three patients who underwent LI (21.4%) needed thyroxine treatment for post-operative hypothyroidism. One patient (5.5%) needed completion thyroidectomy.

CONCLUSIONS

In this children and adolescents population, after performing LI or NR, remaining thyroid tissue stays free of nodules in 72.2% of the cases. A post-operative thyroxin treatment is necessary in 21.4% of cases after LI.

Probiotic gut effect prevents the chronic psychological stress-induced brain activity abnormality in mice

BACKGROUND

A probiotic formulation (Lactobacillus helveticus R0052 and Bifidobacterium longum R0175 combination, Probio'Stick(®) ) displays anxiolytic-like activity and reduces apoptosis in the lymbic system in animal models of depression. Based on the hypothesis that modulation of gut microbiota by this probiotic formulation has beneficial effects on brain activity in stress conditions, we report a set of probiotic-evoked physiological, cellular, and molecular events in the brain of Probio'Stick(®) pretreated mice submitted to chronic psychological stress.

METHODS

Water avoidance stress (WAS) was applied or not (sham). Hypothalamic-pituitary-adrenal (HPA) axis and autonomic nervous system (ANS) responses to the chronic stress were assessed through plasma corticosterone and catecholamine measurements. Specific markers for neuronal activity, neurogenesis, and synaptic plasticity were used to assess brain activity. In addition, gut permeability and tight junction (TJ) proteins levels were also determinated.

KEY RESULTS

We observed that a pretreatment with the probiotic formulation attenuated HPA axis and ANS activities in response to WAS, and reduced cFos expression in different brain areas but Lactobacillus salivarius (a negative control) treatment was ineffective on these parameters. Moreover, probiotic pretreatment prevented the WAS-induced decrease hippocampal neurogenesis and expression changes in hypothalamic genes involved in synaptic plasticity. These central effects were associated with restoration of TJ barrier integrity in stressed mice.

CONCLUSIONS & INFERENCES

These data suggest that chronic stress-induced abnormal brain plasticity and reduction in neurogenesis can be prevented by a pretreatment with the Probio'Stick(®) formulation, suggesting that probiotics modulate neuroregulatory factors and various signaling pathways in the central nervous system involved in stress response.

The hypersensitivity to colonic distension of IBS patients can be transferred to rats through their fecal microbiota

BACKGROUND

Alterations of intestinal microbiota and hypersensitivity to colonic distension are two features of the irritable bowel syndrome (IBS). However, the role of intestinal microbiota in visceral hypersensitivity of IBS patients is far to be established. The aim of our study was to determine whether the intestinal microbiota is involved in the visceral hypersensitivity in IBS.

METHODS

The painful response to colorectal distension and colonic mucosal parameters were assessed in gnotobiotic rats. Germfree (GF) rats were inoculated with the fecal microbiota from IBS patients characterized by hypersensitivity to colorectal distension (IBS HMA rats) or from non-hypersensitive healthy volunteers (Healthy HMA rats). Conventional rats were studied as normosensitivity control. Fecal microbial analyses were carried out in human and HMA rats fecal samples using cultural and molecular approaches.

KEY RESULTS

The microbial dysbiosis of the IBS gut microbiota (more sulfate-reducing bacteria and Enterobacteriaceae and less bifidobacteria) could be maintained in gnotobiotic rats. The number of abdominal contractions in response to colorectal distensions was significantly higher in IBS HMA rats than in healthy HMA rats. No difference was observed between healthy HMA and conventional rats. Colorectal compliance, epithelial paracellular permeability, and density of colonic mucosal mast cells were similar in the three groups of rats.

CONCLUSIONS & INFERENCES

We herein showed that sensitivity to colonic distension of IBS patients can be transferred to rats by the fecal microbiota. Mucosal alterations associated with microbiota transfer are not involved in this hypersensitivity. The altered IBS microbiota may have important role in the hypersensitivity characterizing IBS patients through specific bacterial metabolites.

Cervical lymphadenopathies signaling thyroid microcarcinoma. Case study and review of the literature

BACKGROUND

Some lateral cervical lymphadenopathies may lead to the discovery of papillary microcarcinomas (PMC) of the thyroid that are not radiologically apparent. This relatively rare clinical situation raises questions about the diagnostic approach to chronic cervical lymphadenopathy and the impact of lymph node metastasis on PMC prognosis. PURPOSE OF THE ARTICLE: To study the epidemiologic, clinical, and prognostic criteria of cases of lymphadenopathy that signaled PMC.

PATIENTS AND METHODS

A retrospective study of 167 consecutive cases of PMC compared with 13 cases where a cervical mass signaled other forms of PMC.

RESULTS

The mean age was 48.5 years, the ratio of men to women was 5:8, and the mean PMC size was 5.5mm. These data did not differently significantly from those of the other PMC cases. The preoperative imaging found fluid content in six cases, with microcalcifications in three cases. All cases were treated by modified radical neck dissection on the side with the lymphadenopathy and total thyroidectomy with central neck dissection. The lymphadenopathy included a ruptured capsule in five cases and was accompanied by central lymph node metastases in three cases. Thyroid capsule involvement was significantly more common in cases of PMC discovered due to lymphadenopathy than in other cases of PMC (69% versus 9.7%, respectively; p<0.001). The mean follow-up was 7.3 years. There were no deaths due to PMC signaled by lymphadenopathy. Two cases of lymph node recurrence after 8 and 10 years were controlled by another surgery and radioactive iodine treatment.

CONCLUSION

Any chronic cervical mass should suggest the possibility of thyroid origin, especially in cases with cystic content or microcalcifications in subjects with no particular risk factors. An ultrasound of the thyroid should be done, as well as a fine needle aspiration biopsy of the lymphadenopathy with a thyroglobulin assay. Treatment is the same as for any thyroid carcinoma, and results in a good oncological outcome, despite the possibility of lymph node recurrences.

[Study of the platysma coli muscle vascularisation by the facial artery. Implication during the elevation of the musculo-cutaneous platysma coli muscle flap]

AIM OF THE STUDY

The purpose of this study was to assess the vascularity of the platysma muscle by the branches of the facial artery, in order to determine the best means of harvesting a musculo-cutaneous flap while ensuring maximum vascular security.

PATIENTS AND METHODS

Ten platysma muscles were dissected on 4 fresh specimens and one formaldehyde-preserved specimen. The dissection was performed after injection of the facial artery in 6 cases, while 4 muscles were dissected without any previous injection.

RESULTS

The vascular supply of the platysma muscle comes essentially from the branches of the submental artery and from branches descending straight from the facial artery. Other collateral branches contribute to this vascularization, but their importance is minor. All these arteries reach the muscle, entering its visceral aspect, then proceed to the sternal notch in a radial axis.

CONCLUSION

The size of the flap has to be defined within a quadrilateral figure with its base formed by the mandibular edge and its apex by the inferior limit of the flap. It is essential to preserve the maximum possible muscular thickness, especially on the medial side of the flap. If the facial artery needs to be ligated, this has to be done as it enters the submandibular space in order to protect most of the collateral branches destined to the muscle. The vascularization is then taken back by the homo- and contro-lateral facial vascularisation in an inverted flow in the remaining segment of the facial artery.

Increased faecal serine protease activity in diarrhoeic IBS patients: a colonic lumenal factor impairing colonic permeability and sensitivity

OBJECTIVES

Diarrhoea-predominant irritable bowel syndrome (IBS-D) is characterised by elevated colonic lumenal serine protease activity. The aims of this study were (1) to investigate the origin of this elevated serine protease activity, (2) to evaluate if it may be sufficient to trigger alterations in colonic paracellular permeability (CPP) and sensitivity, and (3) to examine the role of the proteinase-activated receptor-2 (PAR-2) activation and signalling cascade in this process.

PATIENTS AND METHODS

Faecal enzymatic activities were assayed in healthy subjects and patients with IBS, ulcerative colitis and acute infectious diarrhoea. Following mucosal exposure to supernatants from control subjects and IBS-D patients, electromyographic response to colorectal balloon distension was recorded in wild-type and PAR-2(-/-) mice, and CPP was evaluated on colonic strips in Ussing chambers. Zonula occludens-1 (ZO-1) and phosphorylated myosin light chain were detected by immunohistochemistry.

RESULTS

The threefold increase in faecal serine protease activity seen in IBS-D patients compared with constipation-predominant IBS (IBS-C) or infectious diarrhoea is of neither epithelial nor inflammatory cell origin, nor is it coupled with antiprotease activity of endogenous origin. Mucosal application of faecal supernatants from IBS-D patients in mice evoked allodynia and increased CPP by 92%, both of which effects were prevented by serine protease inhibitors and dependent on PAR-2 expression. In mice, colonic exposure to supernatants from IBS-D patients resulted in a rapid increase in the phosphorylation of myosin light chain and delayed redistribution of ZO-1 in colonocytes.

CONCLUSIONS

Elevated colonic lumenal serine protease activity of IBS-D patients evokes a PAR-2-mediated colonic epithelial barrier dysfunction and subsequent allodynia in mice, suggesting a novel organic background in the pathogenesis of IBS.

[Our experience with papillary microcarcinoma of the thyroid]

INTRODUCTION

Papillary microcarcinoma (PMC) of the thyroid gland is high incidence pathology. Most of cases are related to a good prognosis. Conversely, numerous cases are reported with an aggressive course. Prognosis factors are age, size of tumour, multifocality, capsular invasion and cervical lymphadenopathy.

MATERIAL AND METHOD

We have conduced a retrospective study about 4,208 consecutive thyroidectomies over a period of 16 years. 251 cases of papillary cancers were analysed including 64 PMC (25.5%).

RESULTS

90% of PMC were incidentally found and 59% were diagnosed during surgical procedure. Multifocality improved the sensibility of histological diagnosis (P = 0.04). In 78%, total thyroidectomy was performed associated with a selective neck dissection in 47%. In case of extemporaneous diagnosis all partial thyroidectomy was convert into total thyroidectomy. In case of delayed diagnosis and in the absence of unfavourable prognosis factor, no other surgical procedure was carried out. A 7 years mean follow-up revealed only one case of recurrence successfully treated with Iodine 131 ablation. There was no case of death due to PMC.

CONCLUSION

This study confirms the good prognosis of PMC treated according to usual criterions.

Identification of three major phosphorylation sites within HIV-1 capsid. Role of phosphorylation during the early steps of infection

We previously reported the presence of two cellular serine/threonine protein kinases incorporated in human immunodeficiency virus type 1 (HIV-1) particles. One protein kinase is MAPK ERK2 (mitogen-activated protein kinase), whereas the other one, a 53-kDa protein, still needs to be identified. Furthermore, we demonstrated that the capsid protein CAp24 is phosphorylated by one of those two virion-associated protein kinases (Cartier, C., Deckert, M., Grangeasse, C., Trauger, R., Jensen, F., Bernard, A., Cozzone, A., Desgranges, C., and Boyer, V. (1997) J. Virol. 71, 4832-4837). In this study, we showed that CAp24 is not a direct substrate of MAPK ERK2. Moreover, using site-directed mutagenesis of each of the 9 serine residues of CAp24, we demonstrated the phosphorylation of 3 serine residues (Ser-109, Ser-149, and Ser-178) in the CAp24. Substitution of each serine residue did not affect viral budding, nor viral structure. By contrast, substitution of Ser-109, Ser-149, or Ser-178 affects viral infectivity by preventing the reverse transcription process to be completely achieved. Our results suggest that CAp24 serine phosphorylation is essential for viral uncoating process.

Association of ERK2 mitogen-activated protein kinase with human immunodeficiency virus particles

Here we report the presence of a protein kinase activity associated with human immunodeficiency virus type 1 (HIV-1) particles. We observed phosphorylation of five major proteins by the endogenous protein kinase activity. Phosphoamino acid analysis revealed phosphorylated serine and threonine residues. In addition, we observed autophosphorylation of two proteins in the presence of gamma-ATP in an in-gel phosphorylation assay. These two proteins are not linked by a disulfide bond, suggesting that two different protein kinases are associated with HIV-1 virions. Our results indicate the presence of ERK2 mitogen-activated protein kinase and of a 53,000-molecular-weight protein kinase associated with virions. Moreover, the use of different HIV strains derived from T cells and promonocytic cells, as well as the use of human T-cell leukemia virus type 1 particles, demonstrates that ERK2 is strongly associated with retrovirus particles in a cell-independent manner. Exogenous substrates, such as histone proteins, and a viral substrate, such as Gag protein, are phosphorylated by virus-associated protein kinases.

X-ray absorption spectroscopy of carbonyl basket handle Fe(II) porphyrins: the distortion of the tetrapyrrolic macrocycle

The distortion of the tetrapyrrolic macrocycle, the Fe-C-O bond angle and the Fe local electronic structure of carbonyl basket-handle Fe2+ porphyrins as a function of the basket-handle chain length have been studied by X-ray absorption near edge structure (XANES) spectroscopy, both in the solid state and in toluene solution. The Fe-C-O bond angle has been found to be linear in all compounds while the increasing distortion of the macrocycle with shortening of the chain length is indicated by the multiple scattering resonance in the heme plane appearing at 22 eV in the XANES spectrum.

Morphology of Pseudomonas aeruginosa typing phages of the Lindberg set

Eighteen phages were studied by electron microscopy. They belonged to eight morphotypes representing the Myoviridae, Siphoviridae and Podoviridae families of tailed phages. Twelve phages were members of known species and six phages belonged to three new species. Results correlated closely with serological and DNA-DNA hybridization data. Induced and non-induced propagating bacteria were investigated for lysogeny. All strains produced R-type pyocins, phage-like particles or inhibitory reactions. The identity of typing phages should be controlled periodically.