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The spindle generates force to segregate chromosomes at cell division. In mammalian cells, kinetochore-fibers connect chromosomes to the spindle. The dynamic spindle anchors kinetochore-fibers in space and time to move chromosomes. Yet, how it does so remains poorly understood as we lack tools to directly challenge this anchorage. Here, we adapt microneedle manipulation to exert local forces on the spindle with spatiotemporal control. Pulling on kinetochore-fibers reveals the preservation of local architecture in the spindle-center over seconds. Sister, but not neighbor, kinetochore-fibers remain tightly coupled, restricting chromosome stretching. Further, pulled kinetochore-fibers pivot around poles but not chromosomes, retaining their orientation within 3 μm of chromosomes. This local reinforcement has a 20 s lifetime, and requires the microtubule crosslinker PRC1. Together, these observations indicate short-lived, specialized reinforcement in the spindle center. This could help protect chromosome attachments from transient forces while allowing spindle remodeling, and chromosome movements, over longer timescales.

During cell division, the spindle generates force to move chromosomes. In mammals, microtubule bundles called kinetochore-fibers (k-fibers) attach to and segregate chromosomes. To do so, k-fibers must be robustly anchored to the dynamic spindle. We previously developed microneedle manipulation to mechanically challenge k-fiber anchorage, and observed spatially distinct response features revealing the presence of heterogeneous anchorage (Suresh et al., 2020). How anchorage is precisely spatially regulated, and what forces are necessary and sufficient to recapitulate the k-fiber’s response to force remain unclear. Here, we develop a coarse-grained k-fiber model and combine with manipulation experiments to infer underlying anchorage using shape analysis. By systematically testing different anchorage schemes, we find that forces solely at k-fiber ends are sufficient to recapitulate unmanipulated k-fiber shapes, but not manipulated ones for which lateral anchorage over a 3 μm length scale near chromosomes is also essential. Such anchorage robustly preserves k-fiber orientation near chromosomes while allowing pivoting around poles. Anchorage over a shorter length scale cannot robustly restrict pivoting near chromosomes, while anchorage throughout the spindle obstructs pivoting at poles. Together, this work reveals how spatially regulated anchorage gives rise to spatially distinct mechanics in the mammalian spindle, which we propose are key for function.

High-content imaging for compound and genetic profiling is popular for drug discovery but limited to endpoint images of fixed cells. Conversely, electronic-based devices offer label-free, live cell functional information but suffer from limited spatial resolution or throughput. Here, we introduce a semiconductor 96-microplate platform for high-resolution, real-time impedance imaging. Each well features 4096 electrodes at 25 µm spatial resolution and a miniaturized data interface allows 8× parallel plate operation (768 total wells) for increased throughput. Electric field impedance measurements capture >20 parameter images including cell barrier, attachment, flatness, and motility every 15 min during experiments. We apply this technology to characterize 16 cell types, from primary epithelial to suspension cells, and quantify heterogeneity in mixed co-cultures. Screening 904 compounds across 13 semiconductor microplates reveals 25 distinct responses, demonstrating the platform’s potential for mechanism of action profiling. The scalability and translatability of this semiconductor platform expands high-throughput mechanism of action profiling and phenotypic drug discovery applications. Cell-based phenotypic assays link in vitro discovery to disease pathology. Here, the authors report a semiconductor-based microplate platform to perform high-throughput, high-dimensional “electrical imaging” for label-free assessment of live cell morphology and function.

Background Plasma cell disorders are a rare group of hematological malignancies that accounts for 10% of all hematological neoplasms. Solitary plasmacytomas are rarer entities accounting for less than 5% of all the plasma cell dyscrasias. They encompass three subtypes - Solitary Plasmacytoma of Bone (SPB) and Solitary Extramedullary Plasmacytoma (SEP) and multiple solitary plasmacytomas (MSP). In this study, we discuss the clinical, histopathological and immunohistochemical characteristics of solitary plasmacytomas. Methods A 13 year retrospective analysis of solitary plasmacytomas was performed from a single tertiary care center. Bone marrow evaluation was done concurrently at the time of diagnosis to rule out the presence of multiple myeloma. Results A total of 29 cases fulfilled the diagnostic criteria for SP during the study period. SPB accounted for 55.2%, SEP for 44.4% and MSP for 3.4% of the cases. The most common sites involved were the paranasal sinuses and vertebrae. Other infrequent sites included lymph node, tonsil and lungs. The mean age of presentation of SPB was a decade later than SEP. A male preponderance was observed in both subtypes. Conclusion Solitary plasmacytoma is a rare entity, the diagnosis of which requires a systematic approach. There is limited data available in the literature on the clinico-pathological characteristics of SP from India.

Clear cell breast carcinomas are one of the rare types of invasive carcinoma of the breast. Among them, lipid-rich variant is still rare comprising <1%. The tumor derives its name from the intracytoplasmic neutral lipid that gives the cytoplasm a vacuolated and foamy appearance. These tumors are usually hormone receptors negative and Her-2 Neu positive. Here, we report a case of lipid-rich breast carcinoma which showed hormone receptor positivity and Her-2 Neu negative.

ABSTRACT Background: Urothelial carcinomas (UC) account for 6 and 2% of all cancers in men and women, respectively. Human papillomavirus (HPV) is one of the causative agents in cancers of the uterine cervix and head and neck. The role of HPV is also being studied in cancers of the urinary bladder, penis, and prostate. As p16-INK4a is a surrogate marker for high-risk HPVE7 oncoprotein, this study aims to highlight the utility of p16 immunohistochemistry (IHC) in the evaluation of HPV-associated UC. Materials and Methods: A retrospective study was conducted on UC of the bladder received in the Pathology department between January 2013 and December 2018. Bladder biopsies from non-neoplastic lesions served as controls. IHC was done for the detection of the p16 antigen. The p16 staining was recorded as positive, when there was strong staining in >50% of tumor nuclei. The p16 positive and negative tumors were compared based on age, gender, tumor size, grade, and muscle invasion. P value <0.05 was considered statistically significant. Results: The expression of p16 was analyzed in 72 UC and compared with 20 non-neoplastic cases, of which 26.4% of the cases showed p16 expression. The p16 expression was absent in the non-neoplastic lesions. While the majority (87.5%) of the low-grade tumors were negative for p16 expression, 43.8% high-grade tumors were positive. Similarly, a larger proportion of invasive carcinomas (38.8%) expressed p16 as compared to non-invasive carcinomas (13.8%). Thus, p16 expression showed a significant association with grade and stage in these malignancies (P < 0.05). Conclusion: The p16 expression was associated with high-grade and muscle-invasive UC. The p16 was absent in all non-neoplastic and precursor lesions. Thus, it can provide essential information not only about HPV association but also on the prognostic implications for the patients.

Lateral neck masses are common in children, ranging from simple benign diseases to pathologies with malignant potential. Plexiform neurofibromas are extremely rare peripheral nerve sheath tumours involving multiple nerve sheath fascicles. They are typically seen in the paediatric population, with the majority affecting the craniofacial area and neck. Due to the close clinical and histological resemblance with other benign neck lesions such as lymphadenitis and branchial cysts, these cases can often go misdiagnosed. We describe a lesion in a young girl who presented with a progressive lateral neck swelling and how it was managed.

PurposeMetformin is the most commonly prescribed drug in the management of metabolic disorders such as polycystic ovarian syndrome (PCOS) and gestational diabetes in women of reproductive age. Insulin-sensitizing effect of metformin helps in improving from PCOS features such as hyperandrogenism, anovulation, and infertility. However, its ability to cross placental barrier raises concern about safety of the drug on early embryonic development. In this study, we evaluated the effect of metformin on the ovarian function and embryo development.MethodsAdult Swiss albino female mice were administered with metformin (0, 50, 100, and 200 mg/kg body weight) for 4 weeks and assessed for reproductive function and preimplantation embryo development. Further, effect of metformin (0, 10, 25, 50, 100, 250, and 500 μg/mL) exposure to 2-cell-stage embryos was tested under in vitro conditions.ResultsMetformin did not alter the body weight, blood glucose, ovarian weight, and follicular reserve. However, the early embryo development was significantly affected in mice treated with metformin in vivo at highest dose. Moreover, embryos which were exposed to metformin in vitro showed dose-dependent decline in blastocyst rate and hatching rate. Furthermore, at highest concentration of metformin (500 μg/mL), all the embryos were arrested at compaction stage.ConclusionThe study revealed that metformin affects the early embryonic development and raises concern about its use during conception.

Myomatous Erythrocytosis Syndrome is defined as erythrocytosis, myomatous uterus, and the return of normal hematologic values following surgical resection. The exact role of erythropoietin in disease pathogenesis is unknown. In this study we report the case of a 49 year old premenopausal woman who was found to have an enlarged heterogeneous mass arising from the uterus concerning for malignancy. Her RBC count was 5.75 T/L, hemoglobin was 17.6 g/dL and hematocrit was 54.3%. Pre-operative erythropoietin levels were 24.6 mIU/mL and JAK2 mutation was not detected. She underwent Total Abdominal Hysterectomy and Bilateral Salpingo-Oophorectomy. The pathology was consistent with a uterine leiomyoma. Laboratory evaluation performed eight weeks after surgery showed a RBC count of 4.5 T/L, hemoglobin of 13.6 g/dL, hematocrit of 40.5%. Post-operative erythropoietin level was 5.4 mIU/mL. The tissue showed diffuse moderate to strong cytoplasmic immunopositive for Erythropoietin. Erythropoietin plays an important role in this condition, however the exact mechanism is still under investigation. The theory of erythropoietin secreting tumor autonomously without negative feedback is the most credible so far. However, further studies with use of blood erythropoietin level, tissue erythropoietin detection using immune-stain and new molecular biology techniques need to be done and compared to uterine myoma patients with no erythrocytosis. Usually, no further treatment is required following surgical removal.

Benign and malignant bone tumors arise in small bones of the hands and feet. Nevertheless, secondary deposits at these sites are extremely rare. We report a peculiar case of an adult man who presented with thumb swelling, which was later discovered to be a metastasis from renal cell carcinoma. Such cases have a sinister prognosis with a survival rate of 6-12 months from the time of diagnosis. We intend to discuss the diagnostic dilemma and treatment of acrometastases.