Histological and histochemical characterisation of glands associated with the feeding appendages of Argulus foliaceus (Linnaeus, 1758)

Argulus foliaceus (Linnaeus, 1758) is a member of the branchiuran family Argulidae, a group comprising parasitic “fish lice”. A. foliaceus is distributed worldwide and causes major economic impacts for cultured freshwater fish globally. The work described in this study was undertaken with the objective of identifying, describing and characterising glands associated with feeding in A. foliaceus. From structural and ultrastructural microscopic studies of A. foliaceus, three types of gland were determined to be associated with the pre-oral spine and mouth tube and were suggested to be involved in feeding activities. Two of these glands, the labial glands and the proboscis glands, appeared to secrete their products via the mouth tube and a third, the spinal gland, was connected directly to the pre-oral spine. The current study confirmed that the pre-oral spine delivers active secretions from the spinal gland, which may aid in immunomodulation, while the tubular labial spines and proboscis glands openings within the mouth tube may serve to enhance the feeding process by delivering salivary components to aid pre-digestion and immune-modulate the host. The suggested functions are supported by histological and histochemical staining, coupled with fluorescent lectin-binding assays, which enabled characterisation of the carbohydrate moieties associated with these glandular tissues

Cilia Ultrastructure Associated with Primary Ciliary Dyskinesia in Omani Patients

Objectives: Primary ciliary dyskinesia (PCD) is a disorder affecting the structure and function of motile cilia. Transmission electron microscopy is one method that can be used to examine ciliary ultrastructure in airway biopsies. Although the role of ultrastructural findings in PCD has been described in the literature, this role has not been well studied in the Middle East or, by extension, Oman. This study aims to describe ultrastructural features in Omani patients with high suspicion of PCD. Methods: This retrospective cross-sectional study included 129 adequate airway biopsies obtained between 2010–2020 from Omani patients suspected of having PCD. Results: Ciliary ultrastructural abnormalities in our study population were outer dynein arm associated with inner dynein arm defects (8%), microtubular disorganisation associated with inner dynein arm defect (5%), and isolated outer dynein arm defect (2%). Most of the biopsies sowed normal ultrastructure (82%). Conclusion: In Omani patients suspected to have PCD, normal ultrastructure was the commonest feature. Keywords: Cilia; Primary Ciliary Dyskinesia; Airway Biopsy; Transmission Electron Microscopy; Ultrastructure; Oman

Clinical, laboratory and ultrastructural findings in patients with storage pool disease: A case series

Introduction: Platelet storage pool diseases (SPD) are a heterogeneous group of bleeding disorders associated with defects in the storage, secretion, or release of platelet granules. Patients with SPD present with a life-long mucocutaneous bleeding diathesis. Our goal was to study the clinical, laboratory, and ultrastructural changes in platelets of patients diagnosed with SPD using a transmission electron microscope (TEM). Methods: In this retrospective, cross-sectional cohort study, medical records of all patients referred for evaluation of a platelet function disorder were screened for an underlying diagnosis of SPD during the period 2010–2020. Results: Sixty-eight patients were identified, among whom 62 (91.2%) had a platelet function assay (PFA) study, of whom 21 (33.9%) were abnormal. Clinical, laboratory, and light transmission aggregometry (LTA) suggested that 10 (14.7%) patients had SPD; five had gray platelet syndrome (GPS), three had Hermansky Pudlak syndrome (HPS), and two had Chedia-Higashi syndrome (CHS). Most of these cases presented with mucocutaneous bleeding diathesis, but a few had oculocutaneous albinism. They were associated with variable abnormalities in the PFA and LTA studies. However, EM studies using TEM showed a reduction/absence of alpha or delta granules in GPS and HPS patients, respectively, but no abnormality in the granules of CHS patients. Conclusions: Although patients with SPD presented with bleeding diathesis, PFA and platelet aggregation studies were inconclusive. Abnormalities in platelet ultrastructure on EM studies demonstrated corroborative evidence for SPD with absent/reduced alpha or delta granules

Platinum-Based Drugs Differentially Affect the Ultrastructure of Breast Cancer Cell Types

Breast cancer (BC) is the most common cause of cancer-related death worldwide. Although platinum-based drugs (PBDs) are effective anticancer agents, responsive patients eventually become resistant. While resistance of some cancers to PBDs has been explored, the cellular responses of BC cells are not studied yet. Therefore, we aim to assess the differential effects of PBDs on BC ultrastructure. Three representative cells were treated with different concentrations and timing of Cisplatin, Carboplatin, and Oxaliplatin. Changes on cell surface and ultrastructure were detected by scanning (SEM) and transmission electron microscope (TEM). In SEM, control cells were semiflattened containing microvilli with extending lamellipodia while treated ones were round with irregular surface and several pores, indicating drug entry. Prolonged treatment resembled distinct apoptotic features such as shrinkage, membrane blebs, and narrowing of lamellipodia with blunt microvilli. TEM detected PBDs’ deposits that scattered among cellular organelles inducing structural distortion, lumen swelling, chromatin condensation, and nuclear fragmentation. Deposits were attracted to fat droplets, explained by drug hydrophobic properties, while later they were located close to cell membrane, suggesting drug efflux. Phagosomes with destructed organelles and deposits were detected as defending mechanism. Understanding BC cells response to PBDs might provide new insight for an effective treatment

The Diagnostic Yield of Thyroid Function Tests and their Cost-effectiveness in the Student Clinic at Sultan Qaboos University: Retrospective chart review

Objectives: To assess the significance of requesting thyroid function tests (TFT) and their cost effectiveness for specific and non-specific symptoms of thyroid disease in a specific population in Oman. Methods: A retrospective chart review study was conducted in the student clinic at Sultan Qaboos University in Oman in the year 2007–2008. It included all patients (N = 319) of both sexes for whom TFTs were requested. The patients’ main complaints and the final diagnoses were collected from their medical records. Results: The most common presentations for which TFTs were requested were irregular periods (n = 82); fatiguability (n = 49), palpitations (n = 39); weight changes (n = 22); hair changes (n= 20); sensation of heat and cold (n= 18); diarrhoea and constipation (n = 13), and neck swelling (n = 13).The most common diagnoses reached in relation to these complaints were polycystic ovarian syndrome (n = 51); iron deficiency anaemia (n = 42); anxiety and depression (n = 11); thyroid disease (n = 18), and no specific diagnosis (n = 193). The percentage of thyroid diseases among females (7.1%) compared to males (1.2%) was statistically significant (P <0.05). Thyroid disease accounted for 61.5% of those patient with neck swelling, 7.7% of those with palpitations, 4.1% of those with fatigue, 3% of those with other complaints, and 1.2% of those with irregular periods. The cost of the tests was around 20,000 US dollars. Conclusion: TFT is necessary for those presenting with neck swelling, but restraint should be used in administering the test for those complaining of palpitations or fatigue. Additionally, irregular periods have little link with TFT abnormality.

Effect of Smokeless Tobacco Product, Afzal, on the Reproductive Hormones and Gonadal Pathology of Wistar Rats

Afzal is a common smokeless tobacco product (STP) in Oman, and it is believed to contain toxins that may affect the reproductive hormones and hence reproductive function. This study assessed the effect of  Afzal  on the gonads of Wistar rats.  In order to assess gonad toxicity induced by this STP, an aqueous extract of Afzal was added to drinking water to be administrated orally to Wistar albino rats (n = 72) classified as young (4 weeks old) and adult (20 weeks old) of both genders weighing between 60-80 g and 150-240 g respectively for 8 weeks. The rats were divided into 3 groups; control (received distilled water instead of Afzal extract), low-dose (received 3 mg nicotine/kg body weight/day) and high-dose (received 6 mg nicotine/kg body weight/day). At the termination of the study, the rats were euthanized and their blood samples and ovaries were collected for biochemical and histopathological investigations. Testosterone and estradiol hormones showed a significant decrease (P<0.05( in Afzal-treated groups (low and high doses) compared with the control. Histopathological findings revealed the damaging effects manifested as a reduction in the number of the germ cells with deformed organization and in fatty and fibrous degenerations in testes and ovaries. Afzal was found to have adverse effect on the reproductive hormones and gonadal pathology in Wistar rats of both genders, and hence users of Afzal need to consider the risk associated with its frequent use