The functions of the actin nucleator Cobl in cellular morphogenesis critically depend on syndapin I.

Spatial control of cortical actin nucleation is indispensable for proper establishment and plasticity of cell morphology. Cobl is a novel WH2 domain-based actin nucleator. The cellular coordination of Cobl's nucleation activity, however, has remained elusive. Here, we reveal that Cobl's cellular functions are dependent on syndapin. Cobl/syndapin complexes form in vivo, as demonstrated by colocalization, coimmunoprecipitation and subcellular recruitment studies. In vitro reconstitutions and subcellular fractionations demonstrate that, via its lipid-binding Fer/CIP4 Homology (FCH)-Bin/Amphiphysin/Rvs (F-BAR) domain, syndapin recruits Cobl to membranes. Consistently, syndapin I RNAi impairs cortical localization of Cobl. Further functional studies in neurons show that Cobl and syndapin I work together in dendritic arbor development. Importantly, both proteins are crucial for dendritogenesis. Cobl-mediated functions in neuromorphogenesis critically rely on syndapin I and interestingly also on Arp3. Endogenous Cobl, syndapin I and the Arp2/3 complex activator and syndapin-binding partner N-WASP were present in one complex, as demonstrated by coimmunoprecipitations. Together, these data provide detailed insights into the molecular basis for Cobl-mediated functions and reveal that different actin nucleators are functionally intertwined by syndapin I during neuromorphogenesis.

Proper synaptic vesicle formation and neuronal network activity critically rely on syndapin I.

Synaptic transmission relies on effective and accurate compensatory endocytosis. F-BAR proteins may serve as membrane curvature sensors and/or inducers and thereby support membrane remodelling processes; yet, their in vivo functions urgently await disclosure. We demonstrate that the F-BAR protein syndapin I is crucial for proper brain function. Syndapin I knockout (KO) mice suffer from seizures, a phenotype consistent with excessive hippocampal network activity. Loss of syndapin I causes defects in presynaptic membrane trafficking processes, which are especially evident under high-capacity retrieval conditions, accumulation of endocytic intermediates, loss of synaptic vesicle (SV) size control, impaired activity-dependent SV retrieval and defective synaptic activity. Detailed molecular analyses demonstrate that syndapin I plays an important role in the recruitment of all dynamin isoforms, central players in vesicle fission reactions, to the membrane. Consistently, syndapin I KO mice share phenotypes with dynamin I KO mice, whereas their seizure phenotype is very reminiscent of fitful mice expressing a mutant dynamin. Thus, syndapin I acts as pivotal membrane anchoring factor for dynamins during regeneration of SVs.

The actin nucleator Cobl is crucial for Purkinje cell development and works in close conjunction with the F-actin binding protein Abp1.

Cortical actin dynamics shapes cells. To generate actin filaments, cells rely on actin nucleators. Cobl is a novel, brain-enriched, WH2 domain-based actin nucleator, yet, its functions remained largely elusive. Here, we reveal that Cobl plays a crucial role in Purkinje cell development using gene gun transfections within intact murine cerebellar contexts. Cobl deficiency impaired proper dendritic arborization of Purkinje cells and led to low-complexity arbors. Branch point numbers and density and especially higher order branching were strongly affected. Our efforts to reveal how Cobl is physically and functionally integrated into the cortical actin cytoskeleton showed that all Cobl loss-of-function phenotypes were exactly mirrored by knockdown of the F-actin-binding protein Abp1. By subcellular fractionations, protein interaction analyses, subcellular reconstitutions of protein complexes, colocalization studies in cells and tissues, and by functional analyses in neuronal morphogenesis we demonstrate that both proteins associate and work with each other closely. Cobl-mediated dendritic branch induction in hippocampal neurons critically relied on Abp1. Our study highlights that the functions of Abp1 are distinct from those of the Cobl-binding protein syndapin I. The importance of Cobl/Abp1 complex formation and of Abp1-mediated F-actin association was highlighted by functional rescue experiments demonstrating that a Cobl mutant deficient for Abp1 binding and an Abp1 mutant supporting Cobl association but lacking the F-actin binding ability failed to rescue the respective loss-of-function phenotypes. Thus, F-actin-anchored Cobl/Abp1 complexes seem crucial for neuromorphogenesis processes, particularly for the postnatal arborization of Purkinje cells representing the source for all motor coordination in the cerebellar cortex.

Xanthogranulomatous Change in a Leiomyoma: First Report of an Extremely Rare Variant/Degenerative Change.

Xanthogranulomatous inflammation, a specific form of chronic inflammation, is marked by parenchymal destruction, proliferative fibrosis, and infiltration of typical foamy histiocytes admixed with hemosiderin-laden macrophages and foreign-body giant cells. Myometrial xanthomatosis, a term designated for nodular or diffuse histiocytic hyperplasia of the myometrium, has been reported in association with pregnancy-related procedures. Moreover, a 2-3-fold increase in histiocytic counts has been observed in leiomyomatous areas than in adjacent normal myometrium. The first evidence of collections of lipid-laden macrophages was documented in the form of yellowish degeneration of uterine leiomyomas. We report a case of xanthogranulomatous change in a leiomyoma in a 47-year-old female who presented with abnormal uterine bleeding. To the best of our knowledge, this is the first report of xanthogranulomatous variant/degenerative change in a leiomyoma. This case highlights a new variant of leiomyoma which both gynecologists and pathologists should be aware of as it may pose a diagnostic challenge both clinically as well as pathologically.

The actin-binding protein Abp1 controls dendritic spine morphology and is important for spine head and synapse formation.

Polymerization and organization of actin into complex superstructures, including those found in dendritic spines, is indispensable for structure and function of neuronal networks. Here we show that the filamentous actin (F-actin)-binding protein 1 (Abp1), which controls Arp2/3 complex-mediated actin nucleation and binds to postsynaptic scaffold proteins of the ProSAP (proline-rich synapse-associated protein 1)/Shank family, has a profound impact on synaptic organization. Overexpression of the two Abp1 F-actin-binding domains increases the length of thin, filopodia-like and mushroom-type spines but dramatically reduces mushroom spine density, attributable to lack of the Abp1 Src homology 3 (SH3) domain. In contrast, overexpression of full-length Abp1 increases mushroom spine and synapse density. The SH3 domain alone has a dominant-negative effect on mushroom spines, whereas the density of filopodia and thin, immature spines remains unchanged. This suggests that both actin-binding and SH3 domain interactions are crucial for the role of Abp1 in spine maturation. Indeed, Abp1 knockdown significantly reduces mushroom spine and synapse density. Abp1 hereby works in close conjunction with ProSAP1/Shank2 and ProSAP2/Shank3, because Abp1 effects were suppressed by ProSAP2 RNA interference and the ProSAP/Shank-induced increase of spine head width is further promoted by Abp1 cooverexpression and reduced on Abp1 knockdown. Also, interfering with the formation of functional Abp1-ProSAP protein complexes prevents ProSAP-mediated spine head extension. Spine head extension furthermore depends on local Arp2/3 complex-mediated actin polymerization, which is controlled by Abp1 via the Arp2/3 complex activator N-WASP (neural Wiskott-Aldrich syndrome protein). Abp1 thus plays an important role in the formation and morphology control of synapses by making a required functional connection between postsynaptic density components and postsynaptic actin dynamics.

A correlation between platelet indices and preeclampsia.

BACKGROUND: Preeclampsia is one of the major health problems causing maternal morbidity and mortality, complicating 3-8% of pregnancies. It has been suggested that the alterations in the coagulation and fibrinolysis play a role in the pathogenesis of preeclampsia. The markers of platelet activation include platelet count, platelet distribution width, mean platelet volume and plateletcrit. STUDY DESIGN: It was a case-controlled study which included a total of 60 patients (30 cases and 30 controls). Blood samples were collected and the platelet indices - platelet count, plateletcrit, mean platelet volume and platelet distribution width - were evaluated using the Sysmex XN1000 and compared between the two groups. RESULTS: The MPV and PDW also showed a significant difference (p>0.05) between the two groups, with a significant positive correlation with increasing blood pressure (MPV - r=+0.6126, p<0.05 and PDW - r=+0.6441, p<0.05). The PC and PCT had lower values in the preeclampsia patients, however the difference between the two groups was not statistically significant. CONCLUSION: The MPV and PDW showed a significant difference between the two groups and increasing values with increasing BP. However, the PC and PCT in our study did not show a significant correlation with preeclampsia. Thus, the platelet indices, mainly the MPV and PDW, which are economical and easily available, can be reliable in the prediction and early diagnosis of preeclampsia, as well as a marker for the severity of preeclampsia.

A Clinicopathological Correlation of International Federation of Gynecology and Obstetrics's PALM-COEIN Classification of Abnormal Uterine Bleeding: Indian Scenario.

BACKGROUND: Abnormal uterine bleeding (AUB) is a common problem affecting the women of reproductive age group and may also have a significant impact on their physical, social, and emotional aspects directly affecting their quality of life. The International Federation of Gynecology and Obstetrics (FIGO) devised a universally acceptable system of nomenclature and classification, namely PALM-COEIN classification of AUB in the year 2011. The objective of the present study was to analyze the structural (PALM) and functional (COEIN) component of FIGO system in the Indian scenario. MATERIALS AND METHODS: Three hundred patients with complaints of AUB were taken. A clinical diagnosis according to PALM-COEIN system was made after thorough history and clinical examination. Additional investigations if required were done, and endometrial sampling or hysterectomy was done whichever indicated. A histological diagnosis was made, and each case was allocated a category according to PALM-COEIN classification. A clinicopathological correlation was done in the hysterectomy cases for structural causes (PALM). RESULTS: Leiomyoma (30%) was the most common cause of AUB closely followed by adenomyosis (29.66%) overall. The clinicopathological correlation in hysterectomy cases was good with concordance rate of 85.03%. The concordance between clinical and pathological diagnoses for AUB-L, AUB-A, AUB-M, and AUB-A, L was statistically significant with P < 05 in positive cases. However, additional finding of adenomyosis was diagnosed in 48.2% of the cases apart from primary clinical diagnosis. CONCLUSION: A good clinicopathological correlation was seen in the cases when classified according to PALM-COEIN classification. The system also provides for consideration of multiple etiologies contributing toward AUB both clinically and histopathologically. However, histopathology remains the cornerstone in establishing the accurate diagnosis as the cases without specific symptoms can be missed clinically.

Small-Cell Neuroendocrine Carcinoma of the Cervix Masquerading as a Cervical Fibroid: Report of a rare entity.

Primary neuroendocrine tumours of the cervix are extremely rare, with an incidence of only 0.5-1%; as such, these entities can present a clinical and diagnostic challenge. Small-cell neuroendocrine carcinomas of the cervix are highly aggressive tumours that have a tendency to metastasise. We report a 44-year-old woman who presented to the Gynaecology Clinic of the Employees State Insurance Corporation Medical College & Hospital, Faridabad, India, in 2016 with menorrhagia. Based on a clinical examination, she was provisionally diagnosed with a cervical fibroid. However, a biopsy revealed features of a small-cell neuroendocrine carcinoma of the cervix which was subsequently confirmed via immunohistochemistry. An accurate diagnosis of a neuroendocrine carcinoma is vital as it forms the basis for treatment decisions as well as informing predictions for long-term survival.

Scar Endometriosis with Rudimentary Horn: An Unusual and Elucidative Report of a Case Diagnosed on Histopathology and Immunohistochemistry.

Endometriosis is defined as the presence of functioning endometrial tissue outside the endometrial cavity. Scar endometriosis, also known as spontaneous abdominal wall endometriosis, is an unusual clinical presentation which often goes unnoticed. It usually develops after pelvic operations. The incidence has been estimated to be only 0.03%-0.15% of all cases of endometriosis. It can be either asymptomatic or present as abdominal wall pain at the site of surgical incision. It is most commonly diagnosed clinically or on ultrasonography. The treatment of choice predominantly remains surgical excision. We present a case of a 24-year-old female (known case of bicornuate uterus) who presented with chief complaints of abdominal pain for 1 month and 6 months after metroplasty. The patient was clinically diagnosed as a case of scar endometriosis with rudimentary horn and fistulous tract and taken up for surgery. Both the scar tissue and fistulous tract were removed and histopathology revealed only endometrial glands without stroma or hemosiderin-laden macrophages. Diagnosis of scar endometriosis was established on positive immunohistochemistry for estrogen and progesterone receptor in endometrial glands. Timely diagnosis and surgical excision of scar endometriosis along with close follow-up are necessary to prevent complications and recurrence.

A correlation between platelet indices and preeclampsia

ABSTRACT Background: Preeclampsia is one of the major health problems causing maternal morbidity and mortality, complicating 3-8% of pregnancies. It has been suggested that the alterations in the coagulation and fibrinolysis play a role in the pathogenesis of preeclampsia. The markers of platelet activation include platelet count, platelet distribution width, mean platelet volume and plateletcrit. Study design: It was a case-controlled study which included a total of 60 patients (30 cases and 30 controls). Blood samples were collected and the platelet indices - platelet count, plateletcrit, mean platelet volume and platelet distribution width - were evaluated using the Sysmex XN1000 and compared between the two groups. Results: The MPV and PDW also showed a significant difference (p > 0.05) between the two groups, with a significant positive correlation with increasing blood pressure (MPV - r = +0.6126, p < 0.05 and PDW - r = +0.6441, p < 0.05). The PC and PCT had lower values in the preeclampsia patients, however the difference between the two groups was not statistically significant. Conclusion: The MPV and PDW showed a significant difference between the two groups and increasing values with increasing BP. However, the PC and PCT in our study did not show a significant correlation with preeclampsia. Thus, the platelet indices, mainly the MPV and PDW, which are economical and easily available, can be reliable in the prediction and early diagnosis of preeclampsia, as well as a marker for the severity of preeclampsia.

ProSAP1 and membrane nanodomain-associated syndapin I promote postsynapse formation and function.

Insights into mechanisms coordinating membrane remodeling, local actin nucleation, and postsynaptic scaffolding during postsynapse formation are important for understanding vertebrate brain function. Gene knockout and RNAi in individual neurons reveal that the F-BAR protein syndapin I is a crucial postsynaptic coordinator in formation of excitatory synapses. Syndapin I deficiency caused significant reductions of synapse and dendritic spine densities. These syndapin I functions reflected direct, SH3 domain-mediated associations and functional interactions with ProSAP1/Shank2. They furthermore required F-BAR domain-mediated membrane binding. Ultra-high-resolution imaging of specifically membrane-associated, endogenous syndapin I at membranes of freeze-fractured neurons revealed that membrane-bound syndapin I preferentially occurred in spines and formed clusters at distinct postsynaptic membrane subareas. Postsynaptic syndapin I deficiency led to reduced frequencies of miniature excitatory postsynaptic currents, i.e., to defects in synaptic transmission phenocopying ProSAP1/Shank2 knockout, and impairments in proper synaptic ProSAP1/Shank2 distribution. Syndapin I-enriched membrane nanodomains thus seem to be important spatial cues and organizing platforms, shaping dendritic membrane areas into synaptic compartments.

Cordon-bleu is an actin nucleation factor and controls neuronal morphology.

Despite the wealth of different actin structures formed, only two actin nucleation factors are well established in vertebrates: the Arp2/3 complex and formins. Here, we describe a further nucleator, cordon-bleu (Cobl). Cobl is a brain-enriched protein using three Wiskott-Aldrich syndrome protein homology 2 (WH2) domains for actin binding. Cobl promotes nonbundled, unbranched filaments. Filament formation relies on barbed-end growth and requires all three Cobl WH2 domains and the extended linker L2. We suggest that the nucleation power of Cobl is based on the assembly of three actin monomers in cross-filament orientation. Cobl localizes to sites of high actin dynamics and modulates cell morphology. In neurons, induction of both neurites and neurite branching is dramatically increased by Cobl expression-effects that critically depend on Cobl's actin nucleation ability. Correspondingly, Cobl depletion results in decreased dendritic arborization. Thus, Cobl is an actin nucleator controlling neuronal morphology and development.