Direct evidence of sex and a hypothesis about meiosis in Symbiodiniaceae

Dinoflagellates in the family Symbiodiniaceae are obligate endosymbionts of diverse marine invertebrates, including corals, and impact the capacity of their hosts to respond to climate change-driven ocean warming. Understanding the conditions under which increased genetic variation in Symbiodiniaceae arises via sexual recombination can support efforts to evolve thermal tolerance in these symbionts and ultimately mitigate coral bleaching, the breakdown of the coral-Symbiodiniaceae partnership under stress. However, direct observations of meiosis in Symbiodiniaceae have not been reported, despite various lines of indirect evidence that it occurs. We present the first cytological evidence of sex in Symbiodiniaceae based on nuclear DNA content and morphology using Image Flow Cytometry, Cell Sorting and Confocal Microscopy. We show the Symbiodiniaceae species, Cladocopium latusorum, undergoes gamete conjugation, zygote formation, and meiosis within a dominant reef-building coral in situ. On average, sex was detected in 1.5% of the cells analyzed (N = 10,000–40,000 cells observed per sample in a total of 20 samples obtained from 3 Pocillopora colonies). We hypothesize that meiosis follows a two-step process described in other dinoflagellates, in which diploid zygotes form dyads during meiosis I, and triads and tetrads as final products of meiosis II. This study sets the stage for investigating environmental triggers of Symbiodiniaceae sexuality and can accelerate the assisted evolution of a key coral symbiont in order to combat reef degradation.

Incidence of postoperative hypocalcaemia in patients with preoperative cytological evidence of Hashimoto’s thyroiditis undergoing thyroidectomy

Background: Hashimoto’s thyroiditis is an autoimmune pathology presents as a painless goiterogenous condition. It manifests as hypothyroidism, occurring in females of the age group 30-40. Patients are operated for cosmetic symptoms or suspicions of malignancy. The surrounding adhesions and fibrosis of the gland makes it more prone for hypocalcaemia post operatively. This study was conducted to find the incidence of hypocalcaemia postoperatively in patients with Hashimoto’s thyroiditis.Methods: Patients above 13 years undergoing total thyroidectomy where completion thyroidectomy after hemi thyroidectomy, concurrent lymph node dissection, patients on calcium therapy or the ones with preexisting hypocalcaemia were excluded from the study. 100 patients were studied from 1 January 2018 to 1 January 2019 and corrected serum calcium levels at 24 hours, 48 hours and 2 weeks estimated postoperatively. Analysis was done using CSC sepi-info software. Qualitative data were analyzed with Chi square, Z test and ANOVA test.Results: Though 32/100 patients had hypocalcemic symptoms only 26 (26%) had low calcium biochemically. The association between Hashimoto’s thyroiditis and post thyroidectomy hypocalcaemia had significant association (p<0.0001). 11.53% (3/26) had recovered in 48 hours and at two weeks 10 patients remained hypocalcemic with a recovery of 61.53%.Conclusions: Hypocalcaemia after total thyroidectomy in Hashimoto’s thyroiditis occurs due to fibrosis in gland, adhesions to the adjacent structures, injury to the parathyroid glands during surgery and non-identification of parathyroid glands.

Intra-articular Injection of a Dextran Polymer Combined with Antibiotic Medications for Bacterial Infective Arthritis in Dogs: 14 Cases

Objectives The aim of this study was to describe the use of an intra-articular delivery of a dextran polymer (IADP) for bacterial infective arthritis in dogs. Materials and Methods Cases of bacterial infective arthritis treated with IADP were reviewed. Resolution of infection was based on joint fluid cytology. Lameness scores, total nucleated cell counts, and per cent neutrophils were monitored throughout treatment. Results There were 14 dogs included in the study. The stifle was the most commonly affected joint. The median number of injections per dog was 3 with a median of 2 weeks between injections. Amikacin was combined with the dextran polymer in 13 cases and imipenem was used in 1 case. Concurrent oral antimicrobials were used in 12/14 cases, and surgery for infection was performed in 10/14 cases. Cytological evidence of infection resolved in 11/14 cases. Median lameness scores throughout treatment decreased from severe (grade ¾) at initial presentation to mild (grade ¼) at the final recheck. Median total nucleated cell counts and per cent neutrophils decreased from 40,000 white blood cell/µL and 91% to 2,200 white blood cell/µL and 4% respectively. A transient worsening of lameness was the main side effect documented in 5/14 cases. Conclusion Intra-articular dextran polymer combined with antimicrobials was generally well tolerated; however, the efficacy of IADP was unknown in this population since most dogs received concurrent oral antimicrobials and/or surgery.

Direct Evidence Of Sex In Symbiodiniaceae And A Hypothesis About Meiosis

Dinoflagellates in the family Symbiodiniaceae are obligate endosymbionts of diverse marine invertebrates, including corals, and impact the capacity of their hosts to respond to climate change-driven ocean warming. Understanding the conditions under which increased genetic variation in Symbiodiniaceae arises via sexual recombination can support efforts to evolve thermal tolerance in these symbionts and ultimately mitigate coral bleaching, the breakdown of the coral-Symbiodiniaceae partnership under stress. However, direct observations of meiosis in Symbiodiniaceae have not been reported, despite various lines of indirect evidence that it occurs. We present the first cytological evidence of sex in Symbiodiniaceae based on nuclear DNA content and morphology using Image Flow Cytometry, Cell Sorting and Confocal Microscopy. We show Symbiodiniaceae cells undergo gamete conjugation, zygote formation and meiosis within a dominant reef-building coral in situ. On average, sex was detected in 1.5% of the cells analyzed (N=10.000-40.000 cells observed per sample in a total of 20 samples obtained from 3 coral colonies). We show that meiosis follows a two-step process described in other dinoflagellates, in which diploid zygotes form dyads during meiosis I and triads and tetrads as final products of meiosis II. This study sets the stage for investigating environmental triggers of Symbiodiniaceae sexuality and can accelerate the assisted evolution of a key coral symbiont in order to combat reef degradation.

Begonia ×dinglensis, a natural hybrid of Philippine Begonia section Baryandra, as evidenced by morphological, phylogenetic and cytological data

Here we describe a natural hybrid of Philippine Begonia from Bulabog Puti-an National Park in Dingle, Iloilo, Panay Island. The hybrid, named Begonia ×dinglensis after its place of origin, grows on moist, coralline-rock slopes at 200 m elevation. Morphological, molecular, and cytological evidence support its origin from natural hybridization between Philippine endemics B. camiguinensis and B. nigritarum.

Chironomus calligraphus Goeldi, 1905 and C. hawaiiensis Grimshaw, 1901 are sibling species

Although Spies et al.’s (2002) thorough analysis of a small sample of the then available specimens of Chironomus calligraphus Goeldi,1905 suggested two distinctly different haplotypes in the mitochondrial COII gene, the corresponding morphological and cytological evidence kept the authors from concluding that there were two species involved. Further obstacles were unusual aspects of the molecular data and the occurrence of both these haplotypes in samples from the Brazilian type locality by Fittkau (1965) from which he had fixed a neotype. This neotype is slide mounted and can no longer yield molecular data. The present author’s analysis of additional material, including the available BARCODE sequences, has confirmed the existence of two forms, perhaps consistent with those found in the COII analysis, and with largely overlapping geographic distributions. One of these forms occurs in Hawaii where it is morphologically indistinguishable from C. hawaiiensis Grimshaw, 1901. It is recommended to apply this name, which takes nomenclatural precedence to the form found in Hawaii, and the name C. calligraphus to the form found to be more common in Fittkau’s type-locality samples.

Study of Correlation of Cytomorphological Features of Lymphocytic Thyroiditis with Biochemical Parameters and Vitamin D Deficiency

Introduction: Fine Needle Aspiration Cytology (FNAC) of the thyroid is a reliable and common method used for diagnosis of chronic Lymphocytic Thyroiditis (LT) which is an autoimmune disease. Vitamin D (Vit D) deficiency, a prevalent health problem, is known to have correlation with various autoimmune diseases especially chronic LT. Aim: To evaluate the relationship between Vit D levels, biochemical parameters with cytomorphological features of LT. Materials and Methods: The present cohort study was conducted on 88 patients with cytological evidence of LT at a thyroid research centre in northern India between June 2017 to September 2018. Thyroid Stimulating Hormone (TSH), Antithyroid Peroxidase (ATPO) Antibody and Vit D levels along with patient’s clinical presentation, and thyroid ultrasound were evaluated for all subjects. The cytological grades and other cytomorphological features were correlated with these parameters. Results: Most of the patients were females (82, 93.2%) who presented with diffuse thyromegaly (69, 78.4%) and had hypothyroidism (58, 65.9%). By cytology grade I thyroiditis (40, 45.5%) was commonest followed by grade II (38, 43.2%). The Vit D deficiency and elevated ATPO were seen in 72 (81.8%) and 78 (88.6%) patients, respectively. Lowest level of Vit D (7.8±4.9 ng/mL) was seen in grade III patients. Significant correlation was observed between ATPO and Vit D levels with cytomorphological grades and some cytomorphological features like Hurthle cell change and plasma cells presence. While TSH levels correlated significantly with cytological grades only in hypothyroid group. Conclusion: This study found that Vit D deficiency and ATPO levels significantly correlates with cytological grades of thyroiditis and affect certain cytomorphological features like plasma cells presence, suggesting lower levels of Vit D and higher ATPO may be related to more active disease.

Development of alien addition lines from Cucumis hystrix in Cucumis sativus: cytological and molecular marker analyses

Transferring desired genes from wild species to cultivars through alien addition lines (AALs) has been shown to be an effective method for genetic improvement. Cucumis hystrix Chakr. (HH, 2n = 24) is a wild species of Cucumis that possesses many resistant genes. A synthetic allotetraploid species, C. hytivus (HHCC, 2n = 38), was obtained from the cross between cultivated cucumber, C. sativus (CC, 2n = 14), and C. hystrix followed by chromosome doubling. Cucumis sativus – C. hystrix AALs were developed by continuous backcrossing to the cultivated cucumbers. In this study, 10 different types of AALs (CC-H01, CC-H06, CC-H08, CC-H10, CC-H12, CC-H06+H09, CC-H06+H10, CC-H06+H12, CC-H08+H10, CC-H01+H06+H10) were identified based on the analysis of fluorescence in situ hybridization (FISH) and molecular markers specific to C. hystrix chromosomes. And the behavior of the alien chromosomes in three AALs (CC-H01, CC-H06+H10, CC-H01+H06+H10) at meiosis was investigated. The results showed that alien chromosomes paired with C. sativus chromosome in few pollen mother cells (PMCs). Further, disomic alien addition lines (DAALs) carrying a pair of C. hystrix chromosome H10 were screened from the selfed progenies of CC-H10. Chromosome pairing between genomes provides cytological evidence for the possible introgression of alien chromosome segments. The development of AALs could serve as a key step for exploiting and utilizing valuable genes from C. hystrix.