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Ultrastructural changes in midgut epithelial cells of Calliphora during the last nine hours of development are described on the basis of a division into four stages. The midgut differentiates into three parts, the anterior midgut part (AMP), the mid-midgut part (MMP), and the posterior midgut part (PMP). The ultrastructure and the developmental changes in it are practically the same in AMP and PMP cells, but the MMP cells show a different pattern. The lateral membrane junctions are more extensive in the MMP than in the AMP and PMP, but the brush-border of MMP cells is less developed. Variations in the number, size, and electron density of vesicles presumably derived from Golgi regions are larger in this part of the midgut than in other parts. Mitochondrial length increases in all three parts of the midgut, as do the nuclear and nucleolar diameters, attended by an increase in the amount of RER. Two other types of cell are found very sporadically in the midgut epithelium, i.e. presumptive larval granular and presumptive imaginal midgut cells. The yolk mass lying in the midgut lumen is considered to be a very active system that can perform many cellular processes. There are important differences in the ultrastructural development of embryonic and pupal midgut epithelial cells, especially in the formation of the brush-border, the elimination of mitochondria, and the storage and consumption of glycogen. [ABSTRACT FROM AUTHOR]

The embryonic development of the brush-border of anterior midgut cells of Calliphora was studied by electron microscopy. Dense surface-forming vesicles, as described by Bonneville (1970), are found prior to microvillus formation. These dense vesicles provide membranous and coating material for the moulding of the microvilli. The number of dense vesicles increases rapidly to a maximum just before brush-border formation, after which it decreases very rapidly, accompanied by an increase in the number of microvilli. Formation of microvilli proceeds in essentially the same way as in Xenopus. First, some of the vesicles fuse with the apical cell membrane, resulting in an increase of the cell surface, part of which is coated with filamentous material deriving from the dense vesicles. This in turn leads to bulging, and short irregular microvilli appear. These are erected and elongated. Prefabricated tubular elements are believed to play a part in this erection and elongation, probably due to the unwinding of spirally coiled strands. Microvillus formation proper lasts 2 to 3 hours in Calliphora. Almost the entire amount of membranous and coating material is prefabricated prior to the formation of microvilli. [ABSTRACT FROM AUTHOR]

Addition of colchicin to nutrient solutions supplied to red clover plants had an inhibitory effect on root development and nodulation. At the lowest colchicin concentrations, a small, non-significant increase in the number of nodules was often observed; in a few experiments a barely significant increase in the number of nodules developing was observed up to concentrations of 10 mg per 1. Colchicin did not influence the growth of Rhizobium and growth of the bacteria in the presence of colchicin (10 mg per 1) had no effect on their subsequent infectivity or ability to fix nitrogen. Treatment with colchicin resulted in the formation of increased numbers of polyploid cells of the clover roots. In addition, it induced the development of deformed root-hairs which probably facilitated infection by Rhizobium and the formation of infection threads. The nodules developing at colchicin concentrations of 10 mg per 1 and higher were small, had an abnormal structure and were ineffective in nitrogen fixation. It is concluded that any stimulatory effect of colchicin on nodulation does not necessarily require to be associated with an increase in the number of polyploid cells in the root cortex. The effect of colchicin can be fully accounted for, initially by the greater number of infections resulting from the development of increased numbers of deformed root hairs, and subsequently by the reduced inhibitory action of the ineffective nodules on the formation of further nodules. [ABSTRACT FROM AUTHOR]

Purpose: This scoping review aims to summarize and explore current literature on the usefulness and clinical implications of pharyngeal high-resolution (impedance) manometry (HRM/HRIM) in head and neck cancer (HNC) patients., Method: Three online databases (MEDLINE, Embase, Scopus, and additionally Google Scholar) were searched until December 2023. Studies using pharyngeal HRM/HRIM to assess swallowing or voicing in HNC patients, written in any language and published in peer-reviewed journals, were considered eligible. Quality check was performed using the Quality Assessment Tool for Quantitative Studies from the Effective Public Healthcare Practice Project. Information about the study population and HRM/HRIM data (equipment, protocol, analysis, and outcomes) were extracted., Results: Eight papers met the inclusion criteria, six utilizing HRM and two HRIM. The study design consisted of case-series (five) and case-control (three). The quality assessment indicated a weak global rating for seven papers and a moderate rating for one for the remaining study. Findings suggest that HNC patients with dysphagia suffer from reduced pressures in the pharynx and upper esophageal sphincter compared to healthy individuals, potentially influenced by tumor characteristics and treatment. Decreased pressures may indicate poor functioning of swallowing musculature and mechanism., Conclusions: Pharyngeal HRM/HRIM is sparsely used for swallowing assessment in HNC patients. However, wider use seems warranted, as it can offer valuable insights into swallowing biomechanics. This can help quantifying the degree and timing of pressures involved in swallowing (problems) and holds potential for clinical applications, such as earlier diagnosis of radiation-induced therapy or surgery complications. Additionally, it can be beneficial in evaluating therapeutic swallowing strategies.

Background: This study investigated long-term outcomes of dysphagia rehabilitation with an adjustable resistance training device (Swallowing Exercise Aid, SEA2.0) in laryngectomized individuals., Methods: Seventeen laryngectomized participants who participated in a Clinical Phase II Trial were reevaluated at T3 (approximately 6 months after T2), including an interview, PROMS, oral intake, and swallowing capacity. Results of T3 were compared with the earlier time points T0 (baseline), T1 (after 6 weeks of training), and T2 (after 8 weeks of rest)., Results: All outcomes at T3 remained improved compared to T0. Compared to findings at T2, participants reported some deterioration in swallowing at T3. Swallowing capacity and oral intake slightly decreased. Swallowing-related quality of life slightly improved., Conclusions: Benefits of swallowing rehabilitation with the SEA2.0 in laryngectomized individuals are still noticeable long term. The need for continued exercising to fully maintain improved function is likely, but the required intensity and extent should be determined in further research., (© 2024 The Author(s). Head & Neck published by Wiley Periodicals LLC.)

The aims of this exploratory study and clinical phase II trial were to assess the specific nature and extent of dysphagia in laryngectomized patients with self-reported dysphagia, and its rehabilitation potential using the novel Swallowing Exercise Aid (SEA 2.0). Twenty laryngectomized patients participated in a six-week exercise program with the SEA 2.0. Exercises consisted of Chin Tuck Against Resistance (CTAR), Jaw Opening Against Resistance (JOAR), and Effortful Swallow Against Resistance, conducted three times per day. Swallowing was assessed at baseline (T0), six (T1) and 14 (T2) weeks, consisting of patient-reported outcomes, BMI, videofluoroscopy, swallowing capacity, and muscle strength measurements. Dysphagia significantly impacts quality of life, with impaired swallowing speed and bolus propulsion as main reported issues. Subjective dysphagia parameters, swallowing capacity, and pharyngeal residue clearance were reduced, but BMI was normal. Muscle and tongue strength were within normal ranges. All participants managed to use the SEA 2.0. Adherence was 95%. At T1, subjective swallowing parameters (MDADI and EAT-10) showed clinically relevant improvements. Objectively, CTAR and JOAR strength increased with 27.4 and 20.1 Newton, respectively. Also, swallowing capacity (from 2.4 g/s to 3.8 g/s) and pharyngeal residue clearance improved. At T2, results were slightly lower than at T1, but still better than at baseline. Dysphagia in laryngectomized patients affects quality of life, but swallowing can be improved with a six-week rehabilitation program using the novel SEA 2.0. Adherence was excellent and several subjective and objective swallowing parameters improved., (© 2024. The Author(s).)

Introduction: Patients with head and neck squamous cell carcinoma (HNSCC) treated with cisplatin-based chemoradiotherapy (CRT) frequently experience irreversible sensorineural hearing loss (SNHL). Patients with low lumbar skeletal muscle index (LSMI) may experience higher serum peak dosages of cisplatin. This study investigated whether pre-treatment low LSMI is associated with increased SNHL upon cisplatin-based CRT., Materials and Methods: LSMI was assessed using routine pre-treatment CT scans. Pure tone audiometry was performed at baseline and at follow-up to assess treatment-related SNHL. Linear mixed models were used to reveal a potential association between the continuous variable LSMI and SNHL., Results: This retrospective cohort study included 81 patients and found a significant association between low LSMI and increased treatment-related SNHL at pure tone frequencies vital for the perception of speech (averaged of 1, 2, and 4 kHz) (p = 0.048)., Conclusions: HNSCC patients with low LSMI suffer increased treatment-related SNHL upon cisplatin-based CRT., (© 2024 The Author(s). Head & Neck published by Wiley Periodicals LLC.)

Objectives: Decision-making for patients with a locally advanced laryngeal carcinoma (T3 and T4) is challenging due to the treatment choice between organ preservation and laryngectomy, both with different and high impact on function and quality of life (QoL). The complexity of these treatment decisions and their possible consequences might lead to decisional conflict (DC). This study aimed to explore the level of DC in locally advanced laryngeal carcinoma patients facing curative decision-making, and to identify possible associated factors., Methods: In this multicenter prospective cohort study, participants completed questionnaires on DC, level of shared decision-making (SDM), and a knowledge test directly after counseling and 6 months after treatment. Descriptive statistics and Spearman correlation tests were used to analyze the data., Results: Directly after counseling, almost all participants (44/45; 98%) experienced Clinically Significant DC score (CSDC >25, scale 0-100). On average, patients scored 47% (SD 20%) correct on the knowledge test. Questions related to radiotherapy were answered best (69%, SD 29%), whilst only 35% (SD 29%) of the questions related to laryngectomy were answered correctly. Patients' perceived level of SDM (scale 0-100) was 70 (mean, SD 16.2), and for physicians this was 70 (SD 1.7)., Conclusion: Most patients with advanced larynx cancer experience high levels of DC. Low knowledge levels regarding treatment aspects indicate a need for better patient counseling., Level of Evidence: 4 Laryngoscope, 134:3604-3610, 2024., (© 2024 The Authors. The Laryngoscope published by Wiley Periodicals LLC on behalf of The American Laryngological, Rhinological and Otological Society, Inc.)

Purpose: To explore current practice variation and degree of consensus among international clinical experts regarding the diagnosis, classification, measurement, and treatment of head and neck lymphedema (HNL) after head and neck cancer treatment., Materials and Methods: We conducted an online Delphi study. Eligible participants were clinical researchers who had (co)authored at least one publication on HNL and healthcare professionals who had treated at least five patients with HNL the last two years. The first round was to collect views about current best practices. The second and third rounds delved deeper into these topics using statements with 7-point adjective rating scales., Results: An expert panel of seventeen participants (7 clinicians, 8 researchers, and 2 others) from 8 countries completed all rounds. Regarding diagnosis, there was limited consensus on most subjects, with palpation being most endorsed. No consensus was reached on the need to use standardized classification systems. As a treatment method, complex decongestive therapy (CDT) was the most commonly used in practice and investigated in the literature. However, no consensus was reached on the importance of aspects of CDT., Conclusions: There is substantial intra- and international practice variation in the management of HNL. This calls for more robust evidence and guidelines.

Purpose: Head and neck cancer (HNC) treatment often leads to physical and psychosocial impairments. Rehabilitation can overcome these limitations and improve quality of life. The aim of this study is to obtain an overview of rehabilitation care for HNC, and to investigate factors influencing rehabilitation provision, in Dutch HNC centers, and to some extent compare it to other countries., Methods: An online survey, covering five themes: organizational structure; rehabilitation interventions; financing; barriers and facilitators; satisfaction and future improvements, among HNC healthcare- and financial professionals of Dutch HNC centers., Results: Most centers (86%) applied some type of rehabilitation care, with variations in organizational structure. A speech language therapist, physiotherapist and dietitian were available in all centers, but other rehabilitation healthcare professionals in less than 60%. Facilitators for providing rehabilitation services included availability of a contact person, and positive attitude, motivation, and expertise of healthcare professionals. Barriers were lack of reimbursement, and patient related barriers including comorbidity, travel (time), low health literacy, limited financial capacity, and poor motivation., Conclusion: Although all HNC centers included offer rehabilitation services, there is substantial practice variation, both nationally and internationally. Factors influencing rehabilitation are related to the motivation and expertise of the treatment team, but also to reimbursement aspects and patient related factors. More research is needed to investigate the extent to which practice variation impacts individual patient outcomes and how to integrate HNC rehabilitation into routine clinical pathways., (© 2024. The Author(s).)