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Time Lapse fotoğraf çekim tekniğini tanımladığımızda Türkçe karşılığında aralıklı çekim, zaman atlatmalı çekim, zaman aşımı fotoğrafçılığı, zaman aralıklı görüntüleme, hızlandırılmış çekim, süreç görüntüleme, anlamları ile ifade edildiği görülmektedir. Time Lapse temelde iki yöntem ile gerçekleştirilir. Birinci yöntem çekilen bir videonun hızlandırılarak oynatılması, ikinci yöntem ise fotoğraf makinesi ile çekilen karelerin ardışık olarak gösterilmesi şeklindedir. Belirli bir zaman diliminde periyodik aralıklar ile çekilen fotoğraf 5sn, 10dk, 1saat vb. bir yazılım aracılığı ile birleştirilir. Birleştirilen görüntüler 1 sn de 24-30 kare olacak şekilde montajlanarak bir video formatında kayıt edilir. Belirli zaman aralıkları ile çekilen fotoğraflar video hızında oynatıldığında, görüntüde belirgin bir hız artışı olur ve zaman hızla geçiyor gibi görünür. Örneğin gökyüzünde ilerleyen bulutlar, bir bitkinin büyüme sureci, bir çiçeğin açma süreci, bir mevsimin geçiş süreci gibi uzun olan zaman dilimleri kısaltılarak 5-10 saniye gibi kısa bir zaman diliminde sunulur. Sinematografik bir teknik olarak kabul edilen time lapse, İngiliz fotoğrafçı Eadweard Muybridge’in “Koşan Atlar” çalışmasının sonrasında keşfedilmeye başlandı. Muybridge, koşan atın fotoğraflarını bir diske yerleştirerek ilk görüntüleri elde etti. 19.yüzyıldan günümüze dek teknik olarak hızlı bir gelişim gösteren fotoğraf, film ve karanlık oda dönemi yerini dijital döneme bıraktı. Bu bağlamda time lapse çekim tekniği de teknolojinin imkânlarından yararlanarak tek bir kamera ile uygulanabilir duruma geldi. Time lapse tekniğinin en büyük problemlerinden biri olan yüksek ışık şiddeti sonucu fotoğrafta oluşan detay kayıplarıdır. Çalışmada bu problemi ortadan kaldırmaya yardımcı olan HDR tekniği ile istenilen sonuca nasıl ulaşıldığına dair bilgi vermek, her iki tekniğin birlikte kullanılmasına ilişkin verilebilecek bilgilere katkıda bulunmak, time lapse tekniğini daha aktif ve başarılı bir sonuca ulaştırmak için çalışmanın yarar sağlayacağı düşünüldü. Modern dünyanın yadsınamaz bir getirisi olan teknoloji, time lapse yönteminde olduğu gibi HDR tekniğinde de ilerlemeler meydana getirdi. Herhangi bir konunun fotoğraflanması gerektiğinde fotoğraflanacak sahnenin enstantene ve diyafram değerlerini belirlemek için gerekli hesaplamaları mevcut makinenin otomatik poz ölçüm sistemine bırakmak en kolay seçimler olarak görülür. Her ne kadar fotoğraf makinesinin konuya göre pozlandırma seçenekleri kolaylık sağlasa da bu her zaman görüntü açısından doğru bir tercih olmayabilir. Fotoğraf makinesi ister giriş seviyesinde isterse de profesyonel seviyede olsun, bir görüntünün en aydınlık ve en karanlık bölümlerindeki ayrıntıları kaydetme konusunda belirli bir sınırlara sahiptir. Kontrastlığı yüksek konuları fotoğraflarken karanlık bölgeler referans alınarak pozlandırıldığında aydınlık bölgedeki detayların kaybolmasına neden olurken, aydınlık bölgeler referans alınarak pozlandırıldığında ise karanlık bölgelerdeki detayların kaybolması kaçınılmaz olur. Fotoğraf makinelerinin kaydedebildiği yüksek dinamik aralığının belirli bir standardının olması çekilen görüntünün sonuçlarında detay kayıplarına sebep olmaktadır, işte bu sebepleri ortadan kaldırmak için geliştirilmiş HDR Hight Dinamic Range/Yüksek Dinamik Aralık tekniği ile fotoğraflanan konunun tüm dinamik aralığı kaydedilebilmektedir. HDR tekniğini uygulama süresi, örtücü enstantene hariç, diyafram, netleme, ISO vb. ayarları sabit tutmak koşulu ile farklı poz değerlerinde çekilen üç ya da daha fazla fotoğraf karelerinin yazılımlar aracılığıyla açık ve koyu ton eşleştirilmelerinin yapılarak istenilen sonuca ulaştırılmasına dayanır. HDR fotoğrafların time lapse videoların oluşumunda kullanılması ile birlikte, insan gözünün gördüğü dinamik aralığa yakın görüntülere ulaşılması sağlanarak daha başarılı sonuçlar elde edildi. Bu kapsamda time lapse ve HDR teknikleri ele alınarak, Time lapse fotoğraf çekimleri doğrultusunda HDR tekniğinin çekimlerde birlikte kullanımının önemine dikkat çekmek ve time lapse tekniğinin uygulama aşamasında karşılaştığı yüksek kontrastlı ışıktan kaynaklanan, görüntüdeki detay kayıplarının HDR yöntemiyle ortadan kaldırılması amaçlandı. Çalışma sonucunda, verilen örnek fotoğraf çekimlerinde HDR uygulaması yapılarak dinamik aralığın artırıldığı gözlemlendi. Görüntülerde ışık şiddetinin yüksek kontrastlığa sahip fotoğraflardaki detay kayıpları HDR tekniği kullanımıyla ortadan kaldırılarak time lapse de yüksek görüntü kalitesine sahip sonuçlar elde edildi.

Germination of akinetes of filamentous heterocyst-forming cyanobacteria of the order Nostocales is an essential process that ensures survival and recolonization after long periods of unfavorable conditions, as desiccation, cold and low light. We studied the morphological, physiological and metabolic changes that occur during germination of akinetes in two model species of cell differentiation, Anabaena variabilis ATCC 29413 and Nostoc punctiforme ATCC 29133, which live in different habitats. We characterized the akinete envelopes and showed their similarity to envelopes of N2-fixing heterocysts. Akinete germination started inside the envelopes and was dependent on light intensity but independent of nitrogen supply. During the germination of A. variabilis akinetes, cell division and heterocyst differentiation were highly accelerated. The energy for cell division was initially supplied by respiration of glycogen and subsequently by photosynthesis. By contrast, during germination of N. punctiforme akinetes, cell division and heterocyst differentiation were slow. During the initial 15-20 h, N. punctiforme akinetes increased in volume and some burst. Only then did intact akinetes start to divide and fully germinate, possibly fueled by nutrients released from dead akinetes. The different strategies used by these different cyanobacteria allow successful germination of dormant cells and recolonization under favorable conditions.

Human immunodeficiency virus 1 (HIV-1) viral protein R (Vpr) has been shown to induce host cell death by increasing the permeability of mitochondrial outer membrane (MOM). The mechanism underlying the damage to the mitochondria by Vpr, however, is not clearly illustrated. In this study, Vpr that is introduced, via transient transfection or lentivirus infection, into the human embryonic kidney cell line HEK293, human CD4(+) T lymphoblast cell line SupT1, or human primary CD4(+) T cells serves as the model system to study the molecular mechanism of Vpr-mediated HIV-1 pathogenesis. The results show that Vpr injures MOM and causes a loss in membrane potential (MMP) by posttranscriptionally reducing the expression of mitofusin 2 (Mfn2) via VprBP-DDB1-CUL4A ubiquitin ligase complex, gradually weakening MOM, and increasing mitochondrial deformation. Vpr also markedly decreases cytoplasmic levels of dynamin-related protein 1 (DRP1) and increases bulging in mitochondria-associated membranes (MAM), the specific regions of endoplasmic reticulum (ER) which form physical contacts with the mitochondria. Overexpression of Mfn2 and DRP1 significantly decreased the loss of MMP and apoptotic cell death caused by Vpr. Furthermore, by employing time-lapse confocal fluorescence microscopy, we identify the transport of Vpr protein from the ER, via MAM to the mitochondria. Taken together, our results suggest that Vpr-mediated cellular damage may occur on an alternative protein transport pathway from the ER, via MAM to the mitochondria, which are modulated by Mfn2 and DRP1.

The formation of a bipolar spindle is critical for accurate segregation of the genome. Maiato and colleagues now demonstrate that CLASPs (cytoplasmic linker associated proteins) prevent spindle multipolarity in a manner independent of end-on kinetochore–microtubule attachments. They propose that CENP-E-mediated traction forces are balanced by CLASP-mediated recruitment of ninein to centriolar satellites. Loss of spindle-pole integrity during mitosis leads to multipolarity independent of centrosome amplification 1 , 2 , 3 , 4 . Multipolar-spindle conformation favours incorrect kinetochore–microtubule attachments, compromising faithful chromosome segregation and daughter-cell viability 5 , 6 . Spindle-pole organization influences and is influenced by kinetochore activity 7 , 8 , but the molecular nature behind this critical force balance is unknown. CLASPs are microtubule-, kinetochore- and centrosome-associated proteins whose functional perturbation leads to three main spindle abnormalities: monopolarity, short spindles and multipolarity 9 , 10 , 11 , 12 , 13 . The first two reflect a role at the kinetochore–microtubule interface through interaction with specific kinetochore partners 10 , 11 , 14 , but how CLASPs prevent spindle multipolarity remains unclear. Here we found that human CLASPs ensure spindle-pole integrity after bipolarization in response to CENP-E- and Kid-mediated forces from misaligned chromosomes. This function is independent of end-on kinetochore–microtubule attachments and involves the recruitment of ninein to residual pericentriolar satellites. Distinctively, multipolarity arising through this mechanism often persists through anaphase. We propose that CLASPs and ninein confer spindle-pole resistance to traction forces exerted during chromosome congression, thereby preventing irreversible spindle multipolarity and aneuploidy.

We have previously shown that Jak3 is involved in the signaling pathways of CCR7, CCR9 and CXCR4 in murine T lymphocytes and that Jak3⁻/⁻ lymphocytes display an intrinsic defect in homing to peripheral lymph nodes. However, the molecular mechanism underlying the defective migration observed in Jak3⁻/⁻ lymphocytes remains elusive. Here, it is demonstrated for the first time, that Jak3 is required for the actin cytoskeleton reorganization in T lymphocytes responding to chemokines. It was found that Jak3 regulates actin polymerization by controlling cofilin inactivation in response to CCL21 and CXCL12. Interestingly, cofilin inactivation was not precluded in PTX- treated cells despite their impaired actin polymerization. Additionally, Jak3 was required for small GTPases Rac1 and RhoA activation, which are indispensable for acquisition of the migratory cell phenotype and the generation of a functional leading edge and uropod, respectively. This defect correlates with data obtained by time-lapse video-microscopy showing an incompetent uropod formation and impaired motility in Jak3-pharmacologically inhibited T lymphocytes. Our data support a new model in which Jak3 and heterotrimeric G proteins can use independent, but complementary, signaling pathways to regulate actin cytoskeleton dynamics during cell migration in response to chemokines.

Der Nachweis von Chromosomenfehlverteilungen, Aneuploidien, erfolgt in der Regel an der Eizelle (1./2. Polkörper) oder am Embryo (Blastomere, Trophektodermzelle der Blastozyste). Für die Diagnostik stehen verschiedene Methoden zur Verfügung; die derzeit international favorisierte ist die Biopsie von Trophektodermzellen in Verbindung mit einer Array-CGH (“comparative genomic hybridization“), wobei letztere künftig durch das NGS („next generation sequencing“) komplementiert wird. Die genannten Verfahren sind invasiv und erlauben eine weitgehend zuverlässige Aussage bezüglich des Vorliegens einer Aneuploidie. Zur Vermeidung einer invasiven Entnahme von embryonalen Zellen werden alternative Methoden diskutiert, mit denen sich Aneuploidien indirekt bzw. auf der Basis von Korrelationen anhand verschiedener Marker nachweisen lassen. Einige Verfahren sind noch im experimentellen Stadium, u. a. Genexpressionsmuster in Kumuluszellen oder die Konzentration bestimmter Metabolome im Kulturmedium. Ein weiteres neues Verfahren ist der Einsatz von Time-lapse-Imaging zur Korrelation morphokinetischer Parameter mit Aneuploidien.

Time-lapse monitoring is increasingly used in fertility laboratories to culture and select embryos for transfer. This method is offered to couples with the promise of improving pregnancy chances, even though there is currently insufficient evidence for superior clinical results. We aimed to evaluate whether a potential improvement by time-lapse monitoring is caused by the time-lapse-based embryo selection method itself or the uninterrupted culture environment that is part of the system. In this three-armed, multicentre, double-blind, randomised controlled trial, couples undergoing in-vitro fertilisation or intracytoplasmic sperm injection were recruited from 15 fertility clinics in the Netherlands and randomly assigned using a web-based, computerised randomisation service to one of three groups. Couples and physicians were masked to treatment group, but embryologists and laboratory technicians could not be. The time-lapse early embryo viability assessment (EEVA; TLE) group received embryo selection based on the EEVA time-lapse selection method and uninterrupted culture. The time-lapse routine (TLR) group received routine embryo selection and uninterrupted culture. The control group received routine embryo selection and interrupted culture. The co-primary endpoints were the cumulative ongoing pregnancy rate within 12 months in all women and the ongoing pregnancy rate after fresh single embryo transfer in a good prognosis population. Analysis was by intention to treat. This trial is registered on the ICTRP Search Portal, NTR5423, and is closed to new participants. 1731 couples were randomly assigned between June 15, 2017, and March 31, 2020 (577 to the TLE group, 579 to the TLR group, and 575 to the control group). The 12-month cumulative ongoing pregnancy rate did not differ significantly between the three groups: 50·8% (293 of 577) in the TLE group, 50·9% (295 of 579) in the TLR group, and 49·4% (284 of 575) in the control group (p=0·85). The ongoing pregnancy rates after fresh single embryo transfer in a good prognosis population were 38·2% (125 of 327) in the TLE group, 36·8% (119 of 323) in the TLR group, and 37·8% (123 of 325) in the control group (p=0·90). Ten serious adverse events were reported (five TLE, four TLR, and one in the control group), which were not related to study procedures. Neither time-lapse-based embryo selection using the EEVA test nor uninterrupted culture conditions in a time-lapse incubator improved clinical outcomes compared with routine methods. Widespread application of time-lapse monitoring for fertility treatments with the promise of improved results should be questioned. Health Care Efficiency Research programme from Netherlands Organisation for Health Research and Development and Merck.

Background Previously manual human embryology in many in vitro fertilization (IVF) centers is rapidly being replaced by closed embryo incubation systems with time-lapse imaging. Whether such systems perform comparably to manual embryology in different IVF patient populations has, however, never before been investigated. We, therefore, prospectively compared embryo quality following closed system culture with time-lapse photography (EmbryoScope™) and standard embryology. We performed a two-part prospectively randomized study in IVF (clinical trial # NCT92256309). Part A involved 31 infertile poor prognosis patients prospectively randomized to EmbryoScope™ and standard embryology. Part B involved embryos from 17 egg donor-recipient cycles resulting in large egg/embryo numbers, thus permitting prospectively alternative embryo assignments to EmbryoScope™ and standard embryology. We then compared pregnancy rates and embryo quality on day-3 after fertilization and embryologist time utilized per processed embryo. Results Part A revealed in poor prognosis patients no differences in day-3 embryo scores, implantation and clinical pregnancy rates between EmbryoScope™ and standard embryology. The EmbryoScope™, however, more than doubled embryology staff time ( P  < 0.0001). In Part B, embryos grown in the EmbyoScope™ demonstrated significantly poorer day-3 quality (depending on embryo parameter between P  = 0.005 and P  = 0.01). Suspicion that conical culture dishes of the EmbryoScope™ (EmbryoSlide™) may be the cause was disproven when standard culture dishes demonstrated no outcome difference in standard incubation. Conclusions Though due to small patient numbers preliminary, this study raises concerns about the mostly uncontrolled introduction of closed incubation systems with time lapse imaging into routine clinical embryology. Appropriately designed and powered prospectively randomized studies appear urgently needed in well-defined patient populations before the uncontrolled utilization of these instruments further expands. Trial registration NCT02246309 Registered September 18, 2014.

Time-lapse imaging systems for embryo incubation and selection might improve outcomes of in-vitro fertilisation (IVF) and intracytoplasmic sperm injection (ICSI) treatment due to undisturbed embryo culture conditions, improved embryo selection, or both. However, the benefit remains uncertain. We aimed to evaluate the effectiveness of time-lapse imaging systems providing undisturbed culture and embryo selection, and time-lapse imaging systems providing only undisturbed culture, and compared each with standard care without time-lapse imaging. We conducted a multicentre, three-parallel-group, double-blind, randomised controlled trial in participants undergoing IVF or ICSI at seven IVF centres in the UK and Hong Kong. Embryologists randomly assigned participants using a web-based system, stratified by clinic in a 1:1:1 ratio to the time-lapse imaging system for undisturbed culture and embryo selection (time-lapse imaging group), time-lapse imaging system for undisturbed culture alone (undisturbed culture group), and standard care without time-lapse imaging (control group). Women were required to be aged 18–42 years and men (ie, their partners) 18 years or older. Couples had to be receiving their first, second, or third IVF or ICSI treatment and could not participate if using donor gametes. Participants and trial staff were masked to group assignment, embryologists were not. The primary outcome was live birth. We performed analyses using the intention-to-treat principle and reported the main analysis in participants with primary outcome data available (full analysis set). The trial is registered on the International Trials Registry (ISRCTN17792989) and is now closed. 1575 participants were randomly assigned to treatment groups (525 participants per group) between June 21, 2018, and Sept 30, 2022. The live birth rates were 33·7% (175/520) in the time-lapse imaging group, 36·6% (189/516) in the undisturbed culture group, and 33·0% (172/522) in the standard care group. The adjusted odds ratio was 1·04 (97·5% CI 0·73 to 1·47) for time-lapse imaging arm versus control and 1·20 (0·85 to 1·70) for undisturbed culture versus control. The risk reduction for the absolute difference was 0·7 percentage points (97·5% CI –5·85 to 7·25) between the time-lapse imaging and standard care groups and 3·6 percentage points (–3·02 to 10·22) between the undisturbed culture and standard care groups. 79 serious adverse events unrelated to the trial were reported (n=28 in time-lapse imaging, n=27 in undisturbed culture, and n=24 in standard care). In women undergoing IVF or ICSI treatment, the use of time-lapse imaging systems for embryo culture and selection does not significantly increase the odds of live birth compared with standard care without time-lapse imaging. Barts Charity, Pharmasure Pharmaceuticals, Hong Kong OG Trust Fund, Hong Kong Health and Medical Research Fund, Hong Kong Matching Fund.