ABSTRACT
BACKGROUND: Salmonella derby (S. derby) is a Gram-negative diplococcus that is common in the digestive tract. Infected patients generally experience symptoms such as fever and diarrhea. Mild cases are mostly self-healing gastroenteritis, and severe cases can cause fatal typhoid fever. Clinical cases are more common in children. The most common form of S. derby infection is self-healing gastroenteritis, in which, fever lasts for about 2 d and diarrhea for < 7 d. S. derby can often cause bacterial conjunctivitis, pneumonia, endocarditis, peritonitis and urethritis. However, intracranial infections in infants caused by S. derby are rare in clinical practice and have not been reported before in China. CASE SUMMARY: A 4-mo-old female infant had recurrent fever for 2 wk, with a maximum body temperature of around 39.4°C. Treatment for infectious fever in a local hospital was ineffective, and she was admitted to our hospital. Before admission, there was one sudden convulsion, characterized by unclear consciousness, limb twitching, gaze in both eyes, and slight cyanosis on the face. Cerebrospinal fluid (CSF) culture was positive for Gram-negative bacilli, which conformed to S. derby. After treatment with meropenem and ceftriaxone antibiotics, the patient was discharged home in a clinically stable state after 4 wk of treatment. CONCLUSION: We reported a rare case of S. derby cultured in CSF. S. derby enters the CSF through the blood-brain barrier, causing purulent meningitis. If not treated timeously, it can lead to serious, life-threatening infection.
ABSTRACT
Aim To evaluate the protective effect of Dexrazoxane(Dex)on onco-Cardiology caused by chemotherapeutic drugs other than anthracycline antitumor drugs using zebrafish embryos, including:cisplatin, paclitaxel, vincristine sulfate, 5-fluorouracil and cyclophosphamide. Methods Zebrafish embryos at 24 hpf(hours post-fertilization)were exposed to different concentrations of drugs. The survival rate and the overall animal morphology at 48 hpf, 72 hpf and 96 hpf were observed with a microscope. Heart rate, ventricular contraction fraction, ventricular volume, and cardiac output were measured and calculated by video recordings made with a VCD system. The protective effect of Dex was evaluated using the established model of onco-Cardiology induced by anti-tumor drugs other than anthracyclines. Results In terms of acute toxicity, cisplatin, vincristine sulfate, 5-fluorouracil and cyclophosphamide all significantly reduced the survival rate of zebrafish embryos. The LC50 value was 437.655, 25.538, 65.606 and 19.021 mmol·L-1, respectively. In addition to paclitaxel, the other four anti-tumor drugs all showed significant changes in overall animal morphology and cardiac function indicators. In the study of the protective effect of Dex on four kinds of tumor heart diseases except anthracyclines, only cisplatin had a significant protective effect, which could improve the cardiotoxicity caused by cisplatin. The optimal concentration of Dex was 80 μmol·L-1. Conclusions Zebrafish models of drug toxicity caused by cisplatin, vincristine sulfate, 5-fluorouracil, and cyclophosphamide is established, which proves that Dex only has a protective effect on the toxicity caused by cisplatin.
ABSTRACT
A series of cage penta-arylated carboranes have been synthesized by palladium-catalyzed intermolecular coupling of the C-carboxylic acid of the monocarba- closo-dodecaborate anion [CB11H12]- with iodoarenes by direct cage B-H bond functionalization. These transformations set a record in terms of one-pot directing group-mediated activation of inert bonds in a single molecule. The methodology is characterized by high yields, good functional group tolerance, and complete cage regioselectivity. The directing group COOH can be easily removed during or after the intermolecular coupling reaction. The mechanistic pathways were probed using density functional theory calculations. A Pd(II)-Pd(IV)-Pd(II) catalytic cycle is proposed, in which initial coupling is followed by preferred B-H activation of the adjacent boron vertex, and continuation of this selectivity results in a continuous walking process of the palladium center. The methodology opens a new avenue toward building blocks with 5-fold symmetry.
ABSTRACT
The mechanisms and chemo- and regioselectivities of Ru(II)-catalyzed decarboxylative C-H alkenylation of aryl carboxylic acids with alkynes were investigated with density functional theory (DFT) calculations. The catalytic cycle involves sequential carboxylate-directed C-H activation, alkyne insertion, decarboxylation and protonation. The facile tether-assisted decarboxylation step directs the intermediate toward the desired decarboxylative alkenylation, instead of typical annulation and double alkenylation pathways. The decarboxylation barrier is very sensitive to the tether length, and only the seven-membered ring intermediate can selectively undergo the designed decarboxylation, suggesting a tether-dependent chemoselectivity. This tether-dependent chemoselectivity also applies to the alkyl tethers. In addition, the polarity of solvent is found to control the chemoselectivity between the decarboxylative alkenylation and [4 + 2] annulation. Solvent with low polarity (toluene) favors the decarboxylation pathway, leading to the decarboxylative alkenylation. Solvent with high polarity (methanol) favors the ionic stepwise C-O reductive elimination pathway, leading to the [4 + 2] annulation. To understand the origins of regioselectivity with asymmetric alkynes, the distortion/interaction analysis was applied to the alkyne insertion transition states, and led to a predictive frontier molecular orbital model. The asymmetric alkynes selectively use the terminal with the larger HOMO orbital coefficient to form the C-C bond in the insertion step.
ABSTRACT
In order to investigate the clinical efficacy of non-myeloablative allogeneic stem cell transplantation (allo-NST) and related technology in patients with hematologic malignancies, twenty-six cases of hematological malignancies (10 AL, 14 CML, 2 MM patients) received NST following conditioning regimens with fludara + cyclophosphamide + ATG (14 cases) and busulfan or melphalan + cyclophosphamide + ATG (12 cases), G-CSF (600 micro g/d) or G-CSF (300 micro g/d) + GM-CSF (300 micro g/d) were used for mobilizing peripheral blood stem cell. A combination of cyclosporine A (CsA) and methotrexate (MTX) was administered for GVHD prophylaxis. Patients will be eligible for donor lymphocyte infusion (DLI) or donor stem cell infusion (DSI) given in graded increments according to the chimeric formation and clinical reaction. Generally the dose of the first infusion was 1 x 10(7)/kg at 4th week post-transplantation. The engraftment analysis included the detection of microsatellite short tandem repeats (STRs), Bcr/Abl fusion gene, Philadelphia chromosome, HLA-locus analysis, sex chromosome and ABO blood type or blood subtype. The results showed that 22 patients (84.62%) were engrafted, among which 18 patients were full donor chimerism (FDC) up to now. Acute GVHD occurred in 3/26 cases (11.54%). Chronic GVHD was diagnosed in 6 of 26 (23.07%) evaluable patients. The incidence of infection and hemorrhage was low and slight. It is concluded that allo-NST is a safe and effective therapeutic method for hematologic malignancies, but the related technology such as selection of indication, conditioning regimen and transplantation immunotherapy should be studied further.
