Synthesis of polyolefin (PO)-based block copolymers is of immense research interest. In this work, we report a strategy for the construction of polystyrene (PS)-block-PO-block-PS, a useful thermoplastic elastomer, directly from olefin and styrene monomers. Multinuclear zinc species Et­[Zn­(CH2)6] a ZnEt were prepared through successive additions of BH3 and Et2Zn to 1,5-hexadiene. Poly­(ethylene-co-propylene) chains were biaxially grown from the −(CH2)6– units in Et­[Zn­(CH2)6] a ZnEt via “coordinative chain transfer polymerization (CCTP)” using the pyridylaminohafnium catalyst. PS chains were subsequently grown in one pot from the generated polymeryl–Zn sites by subsequent introduction of the anionic initiator Me3SiCH2Li·(pmdeta) (pmdeta, pentamethyl­diethylenetriamine) and styrene monomers. The fraction of the extracted PS homopolymer grown from the Me3SiCH2 sites was low (homo-PS (g)/total PS (g), 15–22%). The gel permeation chromatography (GPC) curves shifted evidently after styrene polymerization, and change in the molecular weight (ΔM n, 39–56 kDa) was approximately twice the homo-PS M n (20–23 kDa), in accordance with attachment of the PS chains at both ends of the PO chains. Transmission electron microscopy analysis of the thin films showed segregation of the PS domains in the PO matrix to form spherical or wormlike rippled structures depending on the PS content. The prepared triblock copolymers exhibited elastomeric properties in the cyclic tensile test, similar to the commercial PS-block-poly­(ethylene-co-1-butene)-block-PS.

Obstructive sleep apnea (OSA) is a common disorder characterized by intermittent hypoxia and sleep fragmentation. OSA in middle-aged men is often associated with decreased testosterone secretion, together with obesity and aging. Although OSA treatment does not reliably increase testosterone levels in most studies, OSA treatment with testosterone replacement therapy (TRT) may not only improve hypogonadism, but can also alleviate erectile/sexual dysfunction. However, because TRT may exacerbate OSA in some patients, patients should be asked about OSA symptoms before and after starting TRT. Furthermore, TRT should probably be avoided in patients with severe untreated OSA.

Objective The purpose of this study was to analyze computed tomography (CT) and magnetic resonance (MR) images and to evaluate the maximum standardized uptake value (SUV max) of positron emission tomography (PET)/CT parameters between sinonasal non-Hodgkin's lymphoma (NHL) and squamous cell carcinoma (SCC), knowing the imaging features that distinguish sinonasal NHL from SCC. Study Design Case series with chart review. Setting University tertiary care facility. Subjects and Methods We analyzed the features on CT, MR imaging, and PET/CT of 78 patients diagnosed with sinonasal NHL or SCC histopathologically. The CT (n = 34), MRI (n = 25), and PET/CT (n = 33) images of 39 patients with sinonasal NHL and the CT (n = 38), MR (n = 28), and PET/CT (n = 31) images of 39 patients with SCC were evaluated. The sinonasal NHL was diagnosed as natural killer/T-cell lymphoma (n = 28) and diffuse large B-cell lymphoma (n = 11). Results Patients with sinonasal NHL had a larger tumor volume and higher tumor homogeneity than patients with SCC on T2-weighted and postcontrast MR images. Most of the sinonasal NHL and SCC showed a high degree of enhancement. The apparent diffusion coefficient (ADC) values and adjacent bone destruction were significantly lower in sinonasal NHL than in SCC. However, cervical lymphadenopathy, Waldeyer's ring involvement, and PET/CT SUV max showed no significant differences between sinonasal NHL and SCC. Conclusion CT and MR images of sinonasal masses showing a bulky lesion, marked homogeneity, and low ADC values without adjacent bone destruction are more suggestive of sinonasal NHL than SCC.

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Changes in the configuration of sinonasal cavity after surgery have been assumed to cause changes in the voice quality. The purpose of this study was to know when the hypernasality will be recovered after sinonsal surgery in patients with nasal septal deviation or chronic rhinosinusitis by checking long-term and serially obtained nasalance scores using nasometer. Sixty-five patients underwent sinonasal surgery were included. We classified the subjects into three groups according to the different surgical interventions employed: septoplasty group, endoscopic sinus surgery (ESS) group, and ESS with septoplasty group. The nasalance scores were obtained using a nasometer preoperatively, 1, 2, 3, 4, 5, and 6 months after surgery. The mean nasalance scores for vowels, nasal consonant, plosive consonant-vowel combinations, nasal consonant-vowel combinations, a hypernasality sentence, and hyponasality sentence increased significantly after sinonasal surgery. Hypernasality was most prominent in all groups for all acoustic parameters 1 month after surgery. Thereafter nasality decreased and returned to its preoperative level in all groups at 5 months in the [m], [ma], [mi], and hypernasality sentence, but at 6 months in the [a], [i], [u], [p(h)a], [p(h)i], and hyponasality sentence. Sinonasal surgery can change the acoustic characteristics of the vocal tract and produce a significant increase in nasality. After nasality showed the highest scores at 1-month post-surgery, it returned to its preoperative level at 5 or 6 months after surgery depending on the subtype of speech stimuli.

A practical and simple method for the preparation of ABA-type olefin triblock copolymers, e.g., PE-b-poly­(ethylene-co-propylene)-b-PE, has been described. The performance of the so-called “coordinative chain transfer polymerization” (CCTP) by sequential feed of ethylene and ethylene/propylene mixed gas generated a Zn-bound diblock copolymer (i.e., (PE-b-poly­(ethylene-co-propylene)­yl)2Zn). Treatment of the Zn-bound diblock copolymer with lauroyl peroxide (CH3(CH2)10C­(O)­O-OC­(O)­(CH2)10CH3) led to a C­(sp3)–C­(sp3) coupling reaction between the two diblock chains bound on the zinc site and an ABA-type olefin triblock copolymer, PE-b-poly­(ethylene-co-propylene)-b-PE, was formed. Upon the treatment with lauroyl peroxide, the number-average molecular weight increased by 1.5–1.7 times. The occurrence of the coupling reaction was verified using a model compound, (Oct)2Zn. The ABA-type triblock copolymer exhibited thermoplastic elastomeric properties and dramatically improved mechanical properties (twice the tensile strength and 10-fold increase in the elongation at break) as compared to the diblock congener.

Actinomycosis is a subacute-to-chronic bacterial infection caused by filamentous, gram-positive, non-acid-fast, anaerobic-to-microaerophilic bacteria. It is characterized by continuous spread, suppurative and granulomatous inflammation, and formation of multiple abscesses and sinus tracts that may discharge sulfur granules. Although the most common clinical forms of actinomycosis are cervicofacial, involvement of the nose and paranasal sinuses are extremely rare. Furthermore, nasal cavity actinomycosis mimicking rhinolith has not been reported in the literature previously. This article reports a patient of nasal cavity actinomycosis causing symptoms similar to those of a rhinolith, which was successfully treated by surgical debridement and antibiotic therapy.

Samter’s triad (ST) is a well-known disease characterized by the triad of bronchial asthma, nasal polyps, and aspirin intolerance. Over the past few years, a rapid development in the knowledge of the pathogenesis and clinical characteristics of ST has happened. The aim of this paper is to review the recent investigations on the pathophysiological mechanisms and genetic background, diagnosis, and different therapeutic options of ST to advance our understanding of the mechanism and the therapeutic control of ST. As concern for ST increase, more application of aspirin desensitization will be required to manage this disease successfully. There is also a need for continued research efforts in pathophysiology, treatment, and possible prevention.