scholarly journals Long-Term Survival of Chlamydomonas Reinhardtii During Conditional Senescence

2021 ◽  
Author(s):  
Djihane Yushrina Damoo ◽  
Dion Durnford
Keyword(s):  
Cell Viability ◽  
Chlamydomonas Reinhardtii ◽  
Batch Culture ◽  
Exponential Growth ◽  
Light Stress ◽  
Term Survival ◽  
High Level ◽  
Conditional Senescence ◽  
Related Proteins

Abstract Chlamydomonas reinhardtii undergoes conditional senescence when grown in batch culture due to nutrient limitation. Here we explored plastid and photo-physiological adaptations in Chlamydomonasreinhardtiiduring a long-term ageing experiment by methodically sampling them over 22 weeks. Following exponential growth, Chlamydomonas entered an extended declining growth phase where cells continued to divide, though at a lower rate. Ultimately this ongoing division was fueled by the recycling of macromolecules, that was obvious in the rapidly declining protein and chlorophyll content in the cell during this phase. This process was sufficient to maintain a high level of cell viability as the culture entered stationary phase. Beyond that, cell viability starts to plummet. During the turnover of macromolecules after exponential growth that saw RuBisCO levels drop, the LHCII antenna was relatively stable. This, along with the upregulation of the light stress-related proteins (LHCSR), contributes to an efficient energy dissipation mechanism to protect the ageing cells from photooxidative stress during the senescence process. Ultimately, viability dropped to about 7%at 22 weeks in a batch culture. We anticipate that this research will help further understand the various acclimation strategies carried out by Chlamydomonas to maximize survival under conditional senescence.

scholarly journals Acinetobacter baylyi Starvation-Induced Genes Identified through Incubation in Long-Term Stationary Phase

2010 ◽  
Vol 76 (14) ◽  
pp. 4905-4908 ◽  
Author(s):  
C. Phoebe Lostroh ◽  
Bruce A. Voyles
Keyword(s):  
Gene Expression ◽  
Stationary Phase ◽  
Batch Culture ◽  
Exponential Growth ◽  
Hypothetical Proteins ◽  
Acinetobacter Baylyi ◽  
Metabolic Gene Expression ◽  
Induced Genes ◽  
Dna Maintenance

ABSTRACT Acinetobacter species encounter cycles of feast and famine in nature. We show that populations of A cinetobacter baylyi strain ADP1 remain dynamic for 6 weeks in batch culture. We created a library of lacZ reporters inserted into SalI sites in the genome and then isolated 30 genes with lacZ insertions whose expression was induced by starvation during long-term stationary phase compared with their expression during exponential growth. The genes encode metabolic, gene expression, DNA maintenance, envelope, and conserved hypothetical proteins.

scholarly journals Intracerebral Haemorrhage with Choriocarcinoma in a Teenager - A Case Report

2019 ◽  
Vol 37 (3) ◽  
pp. 151-155
Author(s):  
Sukriti Das ◽  
Md Manirul Islam ◽  
Md Mamunur Rashid ◽  
Md Reaz Ahmed Howlader ◽  
Sharbori Dey ◽  
...  
Keyword(s):  
Case Report ◽  
Ct Scan ◽  
Intracerebral Haemorrhage ◽  
Reproductive Age ◽  
High Concentration ◽  
Intracranial Metastasis ◽  
Term Survival ◽  
X Ray ◽  
High Level

Intracerebral haemorrhage is one of the uncommon initial CNS manifestations of choriocarcinoma in reproductive age group women. Disease is usually diagnosed by history, clinical examinations and investigations like CT scan of brain and chest, MRI of brain, USG, X-ray chest P/A view and high level of â-hCG in serum and CSF. Overall prognosis of this disease is generally good (80-90% long term survival with chemotherapy and radiotherapy). But intracranial metastasis has poor prognosis which comprises 3-28% of choriocarcinoma. Most intracranial metastasis occurs late in the course of disease but 20% experiences as first sign. Our patient is a teenager girl presented with convulsion and loss of consciousness. CT scan of brain revealed hemorrhage in right fronto-parietal region with ventricular extension, X-ray chest P/A view shows metastasis in mid zone of right lung, USG shows invasion in posterior myometrium and high concentration of serum â-hCG (273400 mUI/ ml) confirmed our diagnosis. This case report describes that the conservative treatment with radiotherapy and chemotherapy gives good outcome of with metastasic intracerebral haemorrhage with choriocarcinoma is rewarding with farther radio and chemotherapy. J Bangladesh Coll Phys Surg 2019; 37(3): 151-155

scholarly journals Potential Role of Fomites in the Vehicular Transmission of Human Astroviruses

2001 ◽  
Vol 67 (9) ◽  
pp. 3904-3907 ◽  
Author(s):  
F. Xavier Abad ◽  
Cristina Villena ◽  
Susana Guix ◽  
Santiago Caballero ◽  
Rosa M. Pintó ◽  
...  
Keyword(s):  
Hepatitis A ◽  
Hepatitis A Virus ◽  
Term Survival ◽  
Reverse Transcription Pcr ◽  
Human Astroviruses ◽  
Relevant Role ◽  
Inert Surfaces ◽  
High Level ◽  
Virus Survival

ABSTRACT The persistence of human astroviruses dried on representative porous (paper) and nonporous (china) surfaces was investigated. Long-term astrovirus survival on fomites was monitored by an integrated cell culture-reverse transcription-PCR procedure. Viruses were applied to inanimate surfaces in the presence and absence of fecal material, and their survival was assayed at 4 and 20°C with high relative humidity. Astroviruses exhibited a notable persistence when dried on porous and nonporous materials, particularly at low temperature. Short-term survival of astroviruses on fomites was compared to that of other enteric viruses significant for health, such as rotavirus, adenovirus, poliovirus, and hepatitis A virus. Overall, astroviruses persisted better than poliovirus and adenovirus, although they exhibited a shorter survival than rotavirus and hepatitis A virus. Astroviruses show a high level of persistence at the desiccation step, which is of major significance in determining the chance of subsequent virus survival dried on fomites. Astroviruses are able to survive on inert surfaces long enough to suggest that fomites may play a relevant role in the secondary transmission of astrovirus diarrhea.

scholarly journals Gametic differentiation in Chlamydomonas reinhardtii. I. Production of gametes and their fine structure.

1975 ◽  
Vol 67 (3) ◽  
pp. 587-605 ◽  
Author(s):  
N C Martin ◽  
U W Goodenough
Keyword(s):  
Fine Structure ◽  
Chlamydomonas Reinhardtii ◽  
Time Course ◽  
Nitrogen Starvation ◽  
Morphological Changes ◽  
Culture Conditions ◽  
Homogeneous Material ◽  
Term Survival ◽  
Thin Sections

Gametogenesis in Chlamydomonas reinhardtii has been studied in mating-type plus cells utilizing several different culture conditions, all of which are shown to depend on the depletion of nitrogen from the medium, and the fine structure of gametes prepared under these conditions has been compared by using thin sections of fixed materials. We document alterations in ribosome levels, in chromatin morphology, in starch levels, in the organization of chloroplast membranes, and in the appearance of nuclear envelope and endoplasmic reticulum membranes during gametogenesis. We also noted the acquisition of two new organelles: a mating structure (Friedman, L., A. L. Colwin, and L. H. Colwin. 1968. j. cell Sci. 3:115-128; goodenough, U. W., and R. L. Weiss. 1975. J. Cell Biol. 67:623-637), and Golgi-derived vesicles containing a homogeneous material. We chart the time course of these morphological changes during synchronous gametogenesis. We note that many of these changes may represent adjustments to nitrogen starvation rather than direct features of gametic differentiation, and we also document that cells can differentiate so that they survive conditions of nitrogen starvation for many weeks after they become gametes. We conclude that metabolic alterations, the acquisition of mating ability, and the preparation for long-term survival are all elicited in this organism by nitrogen withdrawal, and we discuss how the various structural alterations observed in this study may relate to these three interrelated avenues of cellular differentiation.

scholarly journals Long-term survival of a patient with locally advanced hilar cholangiocarcinoma (Klatskin tumor): A case report and review on high level evidence

2019 ◽  
Vol 25 (2) ◽  
pp. 25-27
Author(s):  
Jalal Vahedian ◽  
Mohammad Babaei ◽  
Ali Mehrjardi ◽  
Ali Almasi ◽  
Seyyed Ahmadi ◽  
...  
Keyword(s):  
Adjuvant Chemotherapy ◽  
Hilar Cholangiocarcinoma ◽  
Locally Advanced ◽  
Surgical Margin ◽  
R0 Resection ◽  
Klatskin Tumor ◽  
Poor Overall Survival ◽  
Term Survival ◽  
High Level

Cholangiocarcinoma, malignant tumor of epithelial cells of bile ducts has poor overall survival and prognosis. We report a case of non-resectable cholangiocarcinoma with a 57-month survival after incomplete R2 surgical margin resection of the tumor. A 52-year old man with generalized itching, jaundice, brownish urine, mild abdominal pain and weight loss of 8 kg in last two months presented. Imaging and surgical workups showed hilar cholangiocarcinoma (Klatskin tumor). Along with incomplete R2 margin resection we performed stent embedding and post-operative adjuvant chemotherapy. Based on current literature data there is no superiority of adjuvant chemotherapy after complete R0 resection compared to incomplete R2 resection. However, it seems that partial resection along with stent embedding and applied adjuvant chemotherapy in cases of locally advanced non-resectable cholangiocarcinoma may increase survival rate.

scholarly journals CDK9 is a prognostic marker and therapeutic target in pancreatic cancer

Tumor Biology ◽  
2017 ◽  
Vol 39 (2) ◽  
pp. 101042831769430 ◽  
Author(s):  
Anna-Laura Kretz ◽  
Monika Schaum ◽  
Julia Richter ◽  
Ella F Kitzig ◽  
Christine C Engler ◽  
...  
Keyword(s):  
Pancreatic Cancer ◽  
Cell Viability ◽  
Cancer Cells ◽  
Prognostic Marker ◽  
Dependent Manner ◽  
Term Survival ◽  
Long Term Survival ◽  
Pancreatic Cancer Cells ◽  
Promising Therapeutic Approach

Despite recent advances in diagnosis and therapy, prognosis of pancreatic cancer still remains very poor. Besides valid prognostic markers, novel therapeutic approaches are urgently needed. The family of cyclin-dependent kinases comprises 20 kinases which contribute to malignancy by promoting proliferation, migration, invasion, and apoptotic resistance of cancer cells. In this work, we investigated the role of CDK9 in pancreatic cancer. Immunohistochemical analysis of CDK9 expression in tumor and normal tissue of pancreatic cancer patients revealed an overexpression of CDK9 in pancreatic cancer tissue. In addition, high CDK9 expression in tumor tissue is associated with significantly shortened survival, especially in well-differentiated tumors. Moreover, the therapeutic potential of selective CDK9 inhibition on pancreatic cancer cells was evaluated by analysis of cell viability, long-term survival, and induction of apoptosis and characterized by western blotting and flow cytometry. Pharmacological CDK9 inhibition by SNS-032 drastically reduced cell viability in pancreatic cancer cells and potently suppressed long-term survival. Analyzing the mechanism of action revealed that CDK9 inhibition induced apoptosis and cell cycle arrest in a time-dependent manner by suppression of anti-apoptotic proteins. Furthermore, CDK9 inhibition potently enhances the therapeutic effect of chemotherapeutics in pancreatic cancer cells. In conclusion, we identified CDK9 as a negative prognostic marker in pancreatic cancer. Furthermore, pharmacological CDK9 inhibition is a novel and promising therapeutic approach for pancreatic cancer.

scholarly journals Conservation Strategies for Local Breed Biodiversity

Diversity ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 177 ◽  
Author(s):  
D. Phillip Sponenberg ◽  
Alison Martin ◽  
Charlene Couch ◽  
Jeannette Beranger
Keyword(s):  
Conservation Strategies ◽  
Market Demand ◽  
Term Survival ◽  
Local Breed ◽  
Unique Role ◽  
Biodiversity And Ecosystem Function ◽  
High Level ◽  
Effective Conservation ◽  
Formal Recognition

Breeds of domesticated animals are often overlooked as contributing to biodiversity. Their unique role at the junction of natural and human-influenced environments makes them important potential contributors to biodiversity and ecosystem function. Effective conservation of livestock breeds rests upon valid recognition of breeds as repeatable genomic packages with a reasonably high level of predictability for performance. Local or landrace breeds that lack breeder organization are especially difficult to conserve due to lack of formal recognition as breeds. Achieving success with them involves three major steps: Discover, Secure, and Sustain. Early in the process an evaluation of candidate populations for status as genetic resources is essential. This process is aided by a phenotypic matrix which can be used alongside historical investigations and genetic (DNA) studies. The goal is to include all qualifying animals and to exclude all those that do not qualify. Securing some populations depends on careful rescue protocols for maximizing the recovery of genetic variation, and this can then be followed by breeding protocols that provide for maintaining the population’s production potential along with a healthy and viable genetic structure for long-term survival and use. Sustaining breeds for the long term is also enabled by assuring market demand for the breed and its products.

Gastric cancer with high-level microsatellite instability: target gene mutations, clinicopathologic features, and long-term survival

2008 ◽  
Vol 39 (6) ◽  
pp. 925-932 ◽  
Author(s):  
Mario Falchetti ◽  
Calogero Saieva ◽  
Ramona Lupi ◽  
Giovanna Masala ◽  
Piera Rizzolo ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Microsatellite Instability ◽  
Target Gene ◽  
Gene Mutations ◽  
Clinicopathologic Features ◽  
Term Survival ◽  
Long Term Survival ◽  
High Level
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