Impact of Impaired Nasal Breathing on Sleep-Disordered Breathing

Objective: The role of the nose and its importance in the development and severity of sleep-disordered breathing (SDB) is still a matter of discussion. In the first part of this study, often-controversial data and theories about the nose are reviewed concerning its influence on the pathophysiology of SDB and to interpret certain clinical findings connected with impaired nasal breathing. In the second part, the effectiveness of some nonsurgical and surgical therapies is evaluated. Method: A worldwide literature research (Medline) was the basis for this review. Results: The study of the literature on nasal resistance and clinical findings about the effects of incomplete or complete nasal blockage, particularly in comparison of healthy persons and persons with SDB, allows the assumption of the existence of two different groups of responders: a larger group where the importance of the nose for SDB is negligible and a smaller group where the influence of the nose on SDB is crucial. The same seems to hold true for the responses to nonsurgical and surgical treatments with only a few surgical results available in the literature. While the success rate of nasal surgery for patients with obstructive sleep apnea, for instance, seems to be less than 20%, the normalization of nasal resistance often leads to a positive impact on the well-being and the sleep quality of these patients. However, because criteria to identify responders are lacking, the prediction of success of any treatment for the individual with SDB is not possible.     

Serum arginase activity in postsurgical monitoring of patients with colorectal carcinoma

BACKGROUND: Colorectal carcinoma (CRC) is one of the most common malignancies. In the current work, the role of arginase as a diagnostic marker in patients with recurrent CRC and colorectal liver metastases (CRCLM) was studied. METHODS: Arginase activity was monitored in serum from 40 patients with primary CRC and from 100 patients with CRCLM. Blood was taken before and after patients underwent tumor resection. Studies were conducted for 3 years. RESULTS: Preoperative arginase activity in serum from patients with CRC and CRCLM was much greater compared with the arginase activity in serum from healthy control blood donors. One and two cut-off levels of increased arginase activity were observed in patients with CRC and CRCLM, respectively. After patients underwent tumor resection, the arginase activity decreased to normal values in both patients with CRC and patients with CRCLM. Activity levels remained low in patients who did not develop recurrent CRC or CRCLM (first or second). In patients who developed subsequent recurrences or metastases that appeared after surgery, during 3 years of surveillance, a significant rise in serum arginase activity was observed. The clinical prognosis for patients was worst when the postoperative serum arginase activity was very high, because those patients more often developed second liver metastases or died. CONCLUSIONS: The authors conclude that the determination of serum arginase activity may be a complementary test to confirm the occurrence of CRC and may be useful for the early diagnosis of patients who develop recurrent CRC and/or CRCLM.     

Radiocirculography in congenital heart disease in children with intracardiac shunts

A modification of radiocirculography suitable for the investigation of children suffering from congenital heart disease was developed and tested in 55 children with intracardiac shunts. Comparison of data derived from radiocirculography with the data obtained by conventional cardiac catheterisation showed radiocirculography has a high degree of accuracy when it is used to assess shunt size. Pulmonary arterial and capillary pressures and pulmonary resistance values were derived from radiocirculography findings and compared with those obtained from catheterisation studies: only in children of school age could the two be closely correlated. In cyanotic heart disease morphological analysis of the radiocirculographic curves proved an especially helpful diagnostic aid. The close agreement between the assessment of aortic override when using angiography and radiocirculography was demonstrated.     

From manual to artificial intelligence fitting: Two cochlear implant case studies

Objective: To assess whether CI programming by means of a software application using artificial intelligence (AI), FOX®, may improve cochlear implant (CI) performance.

Patients: Two adult CI recipients who had mixed auditory results with their manual fitting were selected for an AI-assisted fitting. Even after 17 months CI experience and 19 manual fitting sessions, the first subject hadn’t developed open set word recognition. The second subject, after 9 months of manual fitting, had developed good open set word recognition, but his scores remained poor at soft and loud presentation levels.

Main outcome measure(s): Cochlear implant fitting parameters, pure tone thresholds, bisyllabic word recognition, phonemic discrimination scores and loudness scaling curves.

Results: For subject 1, a first approach trying to optimize the home maps by means of AI-proposed adaptations was not successful whereas a second approach based on the use of Automaps (an AI approach based on universal, i.e. population based group statistics) during 3 months allowed the development of open set word recognition. For subject 2, the word recognition scores improved at soft and loud intensities with the AI suggestions. The AI-suggested modifications seem to be atypical.

Conclusions: The two case studies illustrate that adults implanted with manual CI fitting may experience an improvement in their auditory results with AI-assisted fitting.     

Phosphatidylinositol-dependent phospholipases C Plc2 and Plc3 of Candida albicans are dispensable for morphogenesis and host-pathogen interaction

Phospholipases play an important role as virulence factors in human pathogens. Candida albicans, the major fungal pathogen of humans, encodes phospholipases of type A, B, C and D. Type B Plb2 and type D Pld1 phospholipases have been shown to contribute to virulence in this organism. We analyzed, in C. albicans, PLC2 and PLC3, two highly conserved genes coding for phosphatidylinositol-dependent phospholipases C with homology to the known virulence factor PlcA in the human pathogen Listeria monocytogenes. We show that expression of PLC2 and PLC3 is upregulated under different filament-inducing conditions and in the constitutive filamentous mutant tup1Delta. In order to analyze PLC2 and PLC3 function in C. albicans, we constructed strains that carry PLC2 or PLC3 under a constitutive promoter and strains that lack all four PLC2/3 alleles. These strains were not affected in their ability to produce filaments under non-inducing conditions, nor was filamentation modified under inducing conditions, suggesting that PLC2/3 are not critical determinants of the yeast-to-hypha switch. In a cell culture model for macrophage interaction, phagocytosis of C. albicans and subsequent killing were not influenced by PLC2/3. These results demonstrate that C. albicans PLC2 and PLC3 are dispensable for virulence; moreover, they underline the sharp contrast with the function of plcA in L. monocytogenes.     

Reactivity of alveolar macrophages during granulomatous inflammation of the lungs under conditions of acute massive blood loss

Reactivity of mouse alveolar macrophages by their ability to phagocytize killedSt. aureus bacteria and production of reactive oxygen metabolites (nitro blue tetrazolium test) in response to zymosan administration was studied under normal conditions and after acute massive blood loss. Zymosan-induced granulomatous inflammation of the lungs during acute massive blood loss 2-fold inhibited the increase in oxidative metabolism of alveolar macrophages. Suppressed production of toxic oxygen radicals in alveolar macrophages was accompanied by accelerated recovery of cells on the surface of the respiratory tract. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 138, No. 9, pp. 257–260, September, 2004