Characterization of the AcrIIC1 anti‒CRISPR protein for Cas9‒based genome engineering in E. coli

Anti-CRISPR proteins (Acrs) block the activity of CRISPR-associated (Cas) proteins, either by inhibiting DNA interference or by preventing crRNA loading and complex formation. Although the main use of Acrs in genome engineering applications is to lower the cleavage activity of Cas proteins, they can also be instrumental for various other CRISPR-based applications. Here, we explore the genome editing potential of the thermoactive type II-C Cas9 variants from Geobacillus thermodenitrificans T12 (ThermoCas9) and Geobacillus stearothermophilus (GeoCas9) in Escherichia coli. We then demonstrate that the AcrIIC1 protein from Neisseria meningitidis robustly inhibits their DNA cleavage activity, but not their DNA binding capacity. Finally, we exploit these AcrIIC1:Cas9 complexes for gene silencing and base-editing, developing Acr base-editing tools. With these tools we pave the way for future engineering applications in mesophilic and thermophilic bacteria combining the activities of Acr and CRISPR-Cas proteins.

Cardiac safety of dual anti-HER2 blockade with pertuzumab plus trastuzumab in early HER2-positive breast cancer in the APHINITY trial

BACKGROUND

Trastuzumab increases the incidence of cardiac events (CEs) in patients with breast cancer (BC). Dual blockade with pertuzumab (P) and trastuzumab (T) improves BC outcomes and is the standard of care for high-risk human epidermal growth factor receptor 2 (HER2)-positive early BC patients. We analyzed the cardiac safety of P and T in the phase III APHINITY trial.

PATIENTS AND METHODS

Left ventricular ejection fraction (LVEF) ≥ 55% was required at study entry. LVEF assessment was carried out every 3 months during treatment, every 6 months up to month 36, and yearly up to 10 years. Primary CE was defined as heart failure class III/IV and a significant decrease in LVEF (defined as ≥10% from baseline and to <50%), or cardiac death. Secondary CE was defined as a confirmed significant decrease in LVEF, or CEs confirmed by the cardiac advisory board.

RESULTS

The safety analysis population consisted of 4769 patients. With 74 months of median follow-up, CEs were observed in 159 patients (3.3%): 83 (3.5%) in P + T and 76 (3.2%) in T arms, respectively. Most CEs occurred during anti-HER2 therapy (123; 77.4%) and were asymptomatic or mildly symptomatic decreases in LVEF (133; 83.6%). There were two cardiac deaths in each arm (0.1%). Cardiac risk factors indicated were age > 65 years, body mass index ≥ 25 kg/m², baseline LVEF between 55% and <60%, and use of an anthracycline-containing chemotherapy regimen. Acute recovery from a CE based on subsequent LVEF values was observed in 127/155 patients (81.9%).

CONCLUSIONS

Dual blockade with P + T does not increase the risk of CEs compared with T alone. The use of anthracycline-based chemotherapy increases the risk of a CE; hence, non-anthracycline chemotherapy may be considered, particularly in patients with cardiovascular risk factors.

[What's about overactive lifestyle in fibromyalgia and chronic fatigue syndrome]

Fibromyalgia and chronic fatigue syndrome are clinical conditions different but they share common components, particularly multifactorial aetiology. High level of action proneness and "overactive" lifestyle can be considered as predisposing risk factors and perpetuating factors for these somatic functional syndromes. For the clinicians managing complex situations, only a holistic, circular and biopsychosocial approach could restore a new equilibrium (allostasis) with strategies of coping with chronic pain and planification of activities.

Psychological impact of the announcement of a fetal abnormality on pregnant women and on professionals

The psychological impact of the announcement of a fetal abnormality after ultrasound examinations is examined in relation to the building up of the mother-child attachment. It represents the "psychological cost" of such techniques. Understanding the subjective experience of the patients could increase the effectiveness of clinical practice. We have assumed that the relationship between parents and professionals is a critical element that contributes to the establishment of an emotional link between the mother and her child. Pregnant women, mothers, and professionals were approached for interviews and by questionnaires including anamnestic data, opinions, and projective methods. The results showed that the women with fetopathy were less centered on themselves during the pregnancy. Long-term effects were found to be important. In pregnant women, ultrasound examination was experienced with satisfaction even if some ambivalence remained. In mothers with an impaired child, ultrasound examination was viewed as a technique with low reliability. Professionals reported not having preparation in making such an announcement. We concluded that a need exists for better management of the modalities of ultrasound examinations. Many parents have expressed their need for psychological support.

Nonarticular complication of heterotopic ossification: a clinical review

Heterotopic ossification (HO) is a complication in neurologic lesions such as head injury and spinal cord injury. Limitation of range of motion and ankylosis as results of HO are well documented. In this report, ten instances of nonarticular complications after development of HO are described. There were three instances of vascular compression, five instances of ulnar nerve compression at the elbow, and two instances of suspected lymphedema. Clinical findings and radiographic evidence of these complications are described. Clinicians should be aware of these complications when HO is diagnosed. In addition, HO should be considered in the differential diagnosis of deep venous thrombosis in spinal cord injured and head injured patients.

Effects of acute cisplatin administration on renal ATPase activities and magnesium excretion of rats

Male Wistar rats were killed 1, 2, or 4 days after a single intraperitoneal injection of cisplatin (5 mg/kg). Functional renal indices, enzymatic activities, and morphological variables were studied. One day after the injection, the treated group showed an increase in the magnesium and phosphate fractional urinary excretion (FE) vs the control group (FE Mg = 5.2 +/- SEM 0.5% vs 13.0 +/- 1.7%; P less than 0.01; and FE P = 4.7 +/- 0.7% vs 14.0 +/- 1.9%; P less than 0.01). Two days after cisplatin administration, a decrease in creatinine clearance of treated animals was found, to 0.33 +/- 0.03 vs 0.51 +/- 0.03 ml/min; P less than 0.05. Na-K-ATPase and ouabain-insensitive ATPase activities were studied in the proximal convoluted tubule, the medullary thick ascending limb of the Henle's loop (mTAL), and the distal convoluted tubule. Only in mTAL one day after the cisplatin injection was there a decrease in Na-K-ATPase activity in the treated group vs controls (1103 +/- 145 vs 1734 +/- 189 pmol Pi/mm.h; P less than 0.05). Morphological studies showed a decrease in mTAL diameters on day 1, and an increase in proximal convoluted tuble diameters at day 2 of treated rats vs controls, at 27.8 +/- 0.6 vs 31.4 +/- 0.7 microns; P less than 0.05, and 50.4 +/- 1.2 vs 47.4 +/- 0.2 microns; P less than 0.05 respectively.(ABSTRACT TRUNCATED AT 250 WORDS)