Bifurcation analysis of a model of tuberculosis epidemic with treatment of wider population suggesting a possible role in the seasonality of this disease.

In this paper, a novel epidemiological model describing the evolution of tuberculosis in a human population is proposed. This model is of the form SEIR, where S stands for Susceptible people, E for Exposed (infected but not yet infectious) people, I for Infectious people, and R for Recovered people. The main characteristic of this model inspired from the disease biology and some realistic hypothesis is that the treatment is administered not only to infectious but also to exposed people. Moreover, this model is characterized by an open structure, as it considers the transfer of infected or infectious people to other regions more conducive to their care and accepts treatment for exposed or infectious patients coming from other regions without care facilities. Stability and bifurcation of the solutions of this model are investigated. It is found that saddle-focus bifurcation occurs when the contact parameter ß passes through some critical values. The model undergoes a Hopf bifurcation when the quality of treatment r is considered as a bifurcation parameter. It is shown also that the system exhibits saddle-node bifurcation, which is a transcritical bifurcation between equilibrium points. Numerical simulations are done to illustrate these theoretical results. Amazingly, the Hopf bifurcation suggests an unexpected and never suggested explanation of seasonality of such a disease, linked to the quality of treatment.

Anatomic variation in the pterygopalatine angle of the maxillary sinus and the maxillary bulla.

Bulges of the most posterior ethmoid air cells into the maxillary sinus were termed maxillary bullæ by Onodi. With few exceptions, they have since been ignored by anatomists through time. Likewise, Sieur cells-the spheno-ethmoido-maxillary air cells-are uncommonly found in anatomical texts. We therefore aimed to perform a retrospective cone beam computed tomography study on 50 patients to document the possibilities of anatomic variation in the situs of the orbital process of palatine bone-a variation related anatomically with the pterygopalatine fossa (PPF) and the respective angle of the maxillary sinus. Commonly occurring pneumatizations in this situs were the Sieur cell (58 %/64 % right/left side), and the maxillary recess of the sphenoidal sinus (20 %/22 % right/left side). Alone or in combination, these determined, but not exclusively, the maxillary bullæ. Uncommon pneumatizations in the anterior wall of the PPF were also found, such as a sphenoidal recess of the maxillary sinus, and lateral (maxillary, or pterygopalatine) recesses of the middle and superior, respectively, nasal meatuses. In two different cases, non-Haller, and non-Sieur posterior ethmoid air cells were found extruded posterior to the maxillary sinus. Significant statistical association indicated bilateral symmetry of Sieur's cell and of the maxillary recess of the sphenoidal sinus. It is important to identify such variant pneumatizations on a case-by-case basis in different surgical procedures and endoscopic corridors.

The pterygopalatine recess of the superior nasal meatus.

The pneumatizations surrounding the pterygopalatine fossa (PPF) and closely related to the sphenopalatine foramen are anatomically variable. During the assessment of a cone beam computed tomography of a 64-year-old male patient, we found bilaterally a previously unreported anatomic variant. This was represented by a lateral or pterygopalatine recess (PPR) of the superior nasal meatus which extended in the anterior wall of the PPF and protruded within the maxillary sinus to determine a maxillary bulla. The PPR was antero-superior to the sphenopalatine foramen. Additionally were found a right nasal septal deviation, seemingly compensated by a left middle concha bullosa and a left prominent ethmoidal bulla. The superior turbinates were also pneumatized. Such anatomic variants related to the pterygopalatine angle of the maxillary sinus should be explored prior to surgical or endoscopic procedures which target the maxillary sinus, the pterygopalatine fossa, or the skull base.

Regenerative potential of human schneiderian membrane: progenitor cells and epithelial-mesenchymal transition.

An innate osteogenic potential of the Schneiderian membrane (SM) is progressively assessed in studies ranging from non-human species to human subjects. It has relevance for endosteal placement and osseointegration. Nestin-expressing osteogenic progenitor cells are allegedly involved in bone formation and remodelling. Nestin phenotype was not assessed previously in human SM. We therefore aimed to fill that particular gap in the literature. Bioptic samples of human adult SM were obtained during surgery from eight adult patients, operated for non-malignant pathologies. Immunohistochemistry on paraffin-embedded tissue samples used primary antibodies against nestin, CD45, CD146, cytokeratin 7 (CK7), and alpha-smooth muscle actin (α-SMA). Nestin expression was consistently found in endothelial cells, and was scarcely encountered in pericytes, putative stromal stem/progenitor cells, as well as in glandular epithelial cells. Moreover, woven bone formation in the periosteal layer of the SM can also be regarded as evidence of the osteogenic potential of this membrane. Nestin and CD45 expression in cells of the primary bone supports the osteogenic potential of SM nestin-expressing cells and a possible involvement of hematopoietic stem cells in maxillary sinus floor remodeling. CD146, a known inducer of epithelial-mesenchymal transition (EMT), was expressed in epithelia, as was CK7. Isolated stromal cells were found expressing CD146, CK7 and α-SMA, suggesting that regenerative processes happening in the SM may also involve processes of EMT which generate stem/progenitor cells. This study provides additional evidence for the regenerative potential of the Schneiderian membrane and identifies potential roles for cells of its stem niche in osteogenesis.

The clinical and epidemiological evolution of varicella in Romania during 2004 and 2013.

INTRODUCTION: Varicella, a vaccine preventable disease (VPD) is one of the most common communicable diseases in Romania. The objectives of our study were to describe the epidemiological evolution of varicella in Romania between 2004 and 2013 and the clinical characteristics of the cases admitted to NIID between 2011 and 2013. MATERIALS AND METHODS: An epidemiological retrospective study was conducted by using the information reported quarterly by general practitioners and hospitals at the national level. There is no system for the surveillance of severe cases in Romania, so, to describe the clinical characteristics of varicella cases, a second retrospective study was developed, in which the patients hospitalized in the NIID, within the period 2011-2013, were included. Questionnaires were completed by using data from the clinical observation forms. Collected information included demographic, clinical and laboratory data, complications, date of onset and admission, length of stay, admission and discharge diagnosis. Data were processed and analyzed by using Microsoft Excel program. RESULTS: A total of 504,844 cases were reported of at the national level between 2004 and 2013, with a mean incidence of 238.2/ 100,000 inhabitants. The most affected age group was 5-9 years old (incidence 1362.7/ 100,000 inhabitants). The study conducted in NIID, registered 353 patients hospitalized with varicella between 2011 and 2013. Most of the hospitalized cases (88.8%) were under 10 years old and many (72.6 %) attended a community. The majority of cases had rash (98.6%) and fever (79.9%). The main complications were pneumonia (46.2%), bacterial infection (16.1%) and encephalitis (2.5%). DISCUSSIONS: Varicella is a very common disease in Romania, which may develop complications. A specific surveillance system should be introduced in order to provide accurate epidemiological, clinical and laboratory information to assess whether varicella is a public health problem in Romania and if the introduction of vaccination in NIP is recommended. However, given the large number of current cases in Romania, a solution may be a sentinel surveillance system type.

Laryngotracheal non-Hodgkin's lymphoma.

OBJECTIVES: Malignant lymphomas of larynx and trachea are rare tumors and require special diagnostic and therapeutic attention. The authors present an unexpected case of nonHodgkin Lymphoma localized in the subglottic larynx and upper cervical trachea. The clinical presentation, diagnostic and therapeutic approach, evolution and prognosis are discussed. METHOD: We report a case of 25-year-old male patient, with progressive dyspnea, presented in our ENT Department with severe airway obstruction caused by a large subglottic tumoral mass migrated in the glottic space during an accidental fall. An emergency tracheotomy was performed. The flexible endoscopy and CT-scan revealed a large mass arising from the subglottic larynx and anterior wall of upper cervical trachea with the obstruction of 2/3 of the laryngotracheal lumen. RESULTS: After a complex assessment, the tumor was excised by external approach (median thyrotomy). The histopathologic exam of the surgical specimen showed malignant nonHodgkin lymphoma and the immunohistochemical profiles were evaluated in order to establish the therapeutic strategy including chemotherapy in the Department of Oncology. CONCLUSIONS: Invasion of the subglottic larynx and trachea by lymphoma is an uncommon problem which can cause severe airway obstruction and requires multidisciplinary approach (ENT, pneumology, oncology/hematology). The clinicopathological features of this case have been described and compared with previously reported cases.

[Thoracoscopic pleurodesis in malignant pleural effusions]. / Pleurodeza toracoscopica in pleureziile maligne.

We performed retrospectively study on 136 thoracoscopies done in our clinic in the period January 2000 and December 2004. We reviewed 136 thoracoscopies, 71 patients were male and 65 were female (mean age 58.4 years). Straw colored effusions were present in 78 cases (57%) and hemorrhagic in 58 cases (43%). The surgical procedure consist in diagnostic of thoracoscopy with drainage of pleural effusion, multiply pleural biopsy, pleurodesis and continuous pleural drainage. In our study, the talc powder (5g) was successfully as sclerosing agent. The primary tumor was: lung-63 (46%), breast-26 (19%), mesothelioma-21 (15.5%), stomach-3, ovarian-3, prostate-3, colon-2, lymphoma-1, leukemia-2, plasmocytoma-1 and unknown primary tumor in 11 cases (8%). Adverse effects included-chest pain-35 cases (25%), fever-20 cases (15%), empyema-6 cases (4.5%), prolonged air leak-5 cases (4%), pulmonary infection-2 cases, acute respiratory failure-1 case, malignant invasion of scar-1 patient. For statistical analysis, the success of talc pleurodesis was defined as the absence of pleural fluid on the follow-up chest radiographs. Pleurodesis was successful in 125 cases (92%) of the patients after 1 month-follow-up. Thoracoscopic talc pleurodesis is a safe, economical and effective treatment for malignant pleural effusion.

[Hereditary lymphedema (Nonne-Milroy-Meige syndrome) associated with chylothorax. Comments on 2 cases]. / Limfedem ereditar (boala Nonne-Milroy-Meige) asociat cu chilotorax. Consideratii pe marginea a doua cazuri.

This paper presents a family case of brother and sister with unilateral lymphedema, set off spontaneously at prepuberty and earlier in the boy. They both developed a unilateral chylothorax at the age of 22-24. No congenital anomalies are present. The clinical and paraclinical data exclude forms of secondary lymphedema as well as the ones associated with gonadal dysgenesis. The family case history reveals that the parents are not kindred, appear healthy, without pulmonary complaints. Neither no other cases similar to the patients described nor other congenital anomalies or genetic diseases have been recorded in the family. The peculiarity of the cases consists in the fact that lymphedema is confined only to the left lower limb and that there are no modifications in the parents, suggesting an autosomal recessive transmission, which would be a pathogenic novelty. The association with chylothorax points to the importance of a thorough evaluation of the patient with lymphedema of the lower limb.