Cyclic di-guanosine monophosphate (di-GMP) is a circular RNA dinucleotide that functions as a second messenger in diverse species of bacteria to trigger wide-ranging physiological changes, including ...cell differentiation, conversion between motile and biofilm lifestyles, and virulence gene expression. However, the mechanisms by which cyclic di-GMP regulates gene expression have remained a mystery. We found that cyclic di-GMP in many bacterial species is sensed by a riboswitch class in messenger RNA that controls the expression of genes involved in numerous fundamental cellular processes. A variety of cyclic di-GMP regulons are revealed, including some riboswitches associated with virulence gene expression, pilus formation, and flagellum biosynthesis. In addition, sequences matching the consensus for cyclic di-GMP riboswitches are present in the genome of a bacteriophage.
Fever may be the only clinical symptom at the onset of infection in neutropenic cancer patients undergoing myelosuppressive chemotherapy. A prompt and evidence-based diagnostic and therapeutic ...approach is mandatory. A systematic search of current literature was conducted, including only full papers and excluding allogeneic hematopoietic stem cell transplant recipients. Recommendations for diagnosis and therapy were developed by an expert panel and approved after plenary discussion by the AGIHO. Randomized clinical trials were mainly available for therapeutic decisions, and new diagnostic procedures have been introduced into clinical practice in the past decade. Stratification into a high-risk versus low-risk patient population is recommended. In high-risk patients, initial empirical antimicrobial therapy should be active against pathogens most commonly involved in microbiologically documented and most threatening infections, including
Pseudomonas aeruginosa
, but excluding coagulase-negative staphylococci. In patients whose expected duration of neutropenia is more than 7 days and who do not respond to first-line antibacterial treatment, specifically in the absence of mold-active antifungal prophylaxis, further therapy should be directed also against fungi, in particular
Aspergillus
species. With regard to antimicrobial stewardship, treatment duration after defervescence in persistently neutropenic patients must be critically reconsidered and the choice of anti-infective agents adjusted to local epidemiology. This guideline updates recommendations for diagnosis and empirical therapy of fever of unknown origin in adult neutropenic cancer patients in light of the challenges of antimicrobial stewardship.
All-
trans
retinoic acid (ATRA) plus arsenic trioxide was found to be noninferior to ATRA plus chemotherapy, and less toxic, in the treatment of acute promyelocytic leukemia. This is an early example ...of a curative therapy for acute leukemia without chemotherapy.
Acute promyelocytic leukemia (APL) has become a highly curable disease with contemporary treatment, which consists of all-
trans
retinoic acid (ATRA) and anthracycline-based chemotherapy.
1
,
2
As reported in several large multicenter trials, this combination results in overall remission rates of up to 95% and cure rates now exceeding 80%.
3
–
11
Thus, the combination of ATRA and chemotherapy is currently considered the standard of care for newly diagnosed APL.
12
Arsenic trioxide is also highly effective in the treatment of APL. Early studies conducted in China and the United States showed that this agent can induce sustained molecular remission when used as . . .
Chronic myeloid leukemia (CML)-study IV was designed to explore whether treatment with imatinib (IM) at 400 mg/day (n=400) could be optimized by doubling the dose (n=420), adding interferon (IFN) ...(n=430) or cytarabine (n=158) or using IM after IFN-failure (n=128). From July 2002 to March 2012, 1551 newly diagnosed patients in chronic phase were randomized into a 5-arm study. The study was powered to detect a survival difference of 5% at 5 years. After a median observation time of 9.5 years, 10-year overall survival was 82%, 10-year progression-free survival was 80% and 10-year relative survival was 92%. Survival between IM400 mg and any experimental arm was not different. In a multivariate analysis, risk group, major-route chromosomal aberrations, comorbidities, smoking and treatment center (academic vs other) influenced survival significantly, but not any form of treatment optimization. Patients reaching the molecular response milestones at 3, 6 and 12 months had a significant survival advantage. For responders, monotherapy with IM400 mg provides a close to normal life expectancy independent of the time to response. Survival is more determined by patients' and disease factors than by initial treatment selection. Although improvements are also needed for refractory disease, more life-time can currently be gained by carefully addressing non-CML determinants of survival.
Background and purpose
We previously reported that certain optical coherence tomography (OCT) measures were sensitive and reliable in identifying idiopathic intracranial hypertension (IIH). This ...prospective study aimed to define OCT measures that allow differentiation of IIH with and without papilledema, thereby helping clinical decision‐making.
Methods
Eight patients with IIH with papilledema, nine without papilledema and 19 with other neurological diseases were included. OCT measures were obtained before lumbar puncture and within 2 h, 1, 3 and 6 months after lumbar puncture with cerebrospinal fluid (CSF) removal.
Results
All patients with papilledema had increased retinal nerve fiber layer (RNFL) thickness and elevated CSF pressure. All patients without papilledema had normal RNFL but elevated CSF pressure. After CSF removal, reduced RNFL thickness was registered in all eight patients with IIH with papilledema. No significant change in RNFL thickness after CSF removal was observed in IIH without papilledema or in patients with other neurological diseases, although reduced CSF pressure was documented. RNFL thickness tended to be normal in patients with IIH with papilledema at 3–6 months after CSF removal. All patients with IIH showed increased rim area and rim thickness, but reduced optic cup volume regardless of RNFL thickness or papilledema.
Conclusions
Retinal nerve fiber layer thickness is sensitive for monitoring acute IIH and evaluating treatment effect. Increased rim area and rim thickness and decreased optic cup volume are reliable parameters that indicate persistently increased CSF pressure and risk of relapse. OCT measures are sensitive and reliable for diagnosing subtle IIH even in the absence of papilledema.
(Stål) and
(Fabricius) are two exotic invasive pests that have invaded the United States in recent years.
can damage various fruits, vegetables, and field crops, such as soybean and corn, while
only ...attacks soybean and kudzu, a weed species. They are currently found in southeastern states and threaten soybean and other crops grown in the region. This study evaluated the seasonal abundance of
.
and
.
in soybeans in 2016 and 2017 in two counties in the central region of Tennessee, where both species had either a few sightings or none that were recorded when this research was being planned. Lures and sweep sampling were used to monitor
.
, and sweep sampling was used to monitor
.
.
was first detected in samples in late July. Their numbers increased in early to mid-September, reached the economic threshold in late Sept, and then started to decline.
was first detected in mid to late July, increased their populations in September, but did not reach the economic threshold and declined mid-October. Our results showed the seasonal abundances of
.
and
.
and their establishment in the central region of Tennessee.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The effects of mechanical or chemical flower and fruit thinning on fruitquality were primarily by altering crop load. However, there were alsodirect effects of thinning agents. Fruit size was ...directly related tothinning intensity. In addition to crop load, age of wood, flower budquality, competition within clusters and canopy were important factorsaffecting the response to thinning. Short- and long-term thinningstudies identified two groups of quality components: Group 1characteristics include size, colour, skin performance, firmness andsugar and acid content of the fruit. Group 2 characteristics wererepresented by inorganic components, especially calcium and potassiumwhich are implicated in the susceptibility of fruit to physiologicaldisorders. While group 1 characteristics were improved by increasingthinning intensity, storability of the fruit was better at high than atlow crop loads. Therefore, a compromise between all quality requirementsmust be found for a good economic return. Establishing the trends ofthinning on the different quality parameters can help to select athinning strategy for local or regional conditions typically beingdetermined by growing and market conditions.PUBLICATION ABSTRACT
The effects of changing ice and atmospheric conditions on the upwelling of deep nutrient‐laden waters and biological productivity in the coastal Beaufort Sea were quantified using a unique ...combination of in situ and remote‐sensing approaches. Repeated instances of ice ablation and upwelling during fall 2007 and summer 2008 multiplied the production of ice algae, phytoplankton, zooplankton and benthos by 2 to 6 fold. Strong wind forcing failed to induce upward shifts in the biological productivity of stratified waters off the shelf.
Key Points
Ice loss can multiply productivity under upwelling‐favorable conditions
Productivity is partly preconditioned by climate forcing in previous fall
Early ice melt is not necessarily detrimental to ice algae, zooplankton, benthos
In the last two decades, remarkable advances have been made in the development of technologies used to engineer new aptamers and ribozymes. This has encouraged interest among researchers who seek to ...create new types of gene-control systems that can be made to respond specifically to small-molecule signals. Validation of the fact that RNA molecules can exhibit the characteristics needed to serve as precision genetic switches has come from the discovery of numerous classes of natural ligand-sensing RNAs called riboswitches. Although a great deal of progress has been made toward engineering useful designer riboswitches, considerable advances are needed before the performance characteristics of these RNAs match those of protein systems that have been co-opted to regulate gene expression. In this review, we will evaluate the potential for engineered RNAs to regulate gene expression and lay out possible paths to designer riboswitches based on currently available technologies. Furthermore, we will discuss some technical advances that would empower RNA engineers who seek to make routine the production of designer riboswitches that can function in eukaryotes.
PDF
