Diagnosis and management of fetal ductus arteriosus constriction-closure.

Pathognomonic features of in utero premature restriction/closure of the ductus arteriosus (DA) are increased right ventricular afterload, impaired right ventricular function, and consequently tricuspid regurgitation and right heart dilation. The most common reason for constriction-closure of DA is maternal administration of non-steroidal anti-inflammatory drugs (NSAIDs) during the 3rd trimester of gestation. The idiopathic form is a rare event and, maybe, an underestimated abnormality that, if it is not promptly recognized, may result in severe fetal-neonatal compromise. We describe a case of a 38-year-old woman presenting at 34+0 weeks of gestation with a normally grown male fetus whose fetal echocardiography had shown right ventricular hypertrophy, a tortuous S-shaped DA and a significant pulmonary hyperflow. All signs were consistent of an idiopathic severe constriction of DA with a significant fetal cardiac involvement. The patient was admitted to a tertiary care center equipped with Neonatal Intensive Care Unit (NICU), and delivered by cesarean section at 34+4 weeks with a good maternal and neonatal outcome. Based on our experience and a review of the Literature we propose a management algorithm to use when dealing with preterm or early term pregnancy complicated by this fetal hemodynamic malfunction.

Detection of the mosquitocidal toxin genes encoding Cry11 proteins from Bacillus thuringiensis using a novel PCR-RFLP method.

A polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method for detection of cry11 genes from Bacillus thuringiensis was established. Based on the analysis of conserved regions of the cry11 genes, 2 oligonucleotide primers were designed to amplify a 1459-bp fragment of the cry11Aa gene, and a 1471-bp of the cry11Ba and cry11Bb genes. The amplification products were digested with restriction endonuclease HinfI. Exotic B. thuringiensis strains and native isolates collected from soils, leaves and stored product dust of Argentina were analyzed to study the distribution of cry11 genes. The PCR-RFLP patterns revealed the detection of cry11 genes in 3 of 64 exotic strains and in 10 of 107 native B. thuringiensis isolates tested. Just the cry11Aa gene subclass was detected among these bacteria. Since the methodology was also developed to detect cry11Ba and cry11Bb genes, an experimental future confirmation will be required. Based on the results obtained, the PCR-RFLP method presented may be a valuable tool for specific detection of the mosquitocidal toxin genes encoding Cry11 proteins from B. thuringiensis.

Characterization of INTA 51-3, a new atypical strain of Bacillus thuringiensis from Argentina.

Several isolates of Bacillus thuringiensis native to Argentina obtained in a nationwide screening program showed atypical crystal morphology. One of these strains, INTA 51-3, was further characterized in order to determine other features like protein composition of its parasporal crystal, plasmid pattern, identification of cry genes and toxicological properties. B. thuringiensis INTA 51-3 (serovar tohokuensis) had an amorphous inclusion containing a major protein component of ca. 130 kDa. After trypsin digestion of solubilized crystals, SDS-PAGE resolved a unique protease-resistant peptide of ca. 90 kDa. The plasmid pattern from INTA 51-3 resembled that of the standard strain HD-1. However, Southern analysis showed no hybridization to fragments of cry1Aa, cry2Aa, cry3A, and cry11A genes. Degenerate primers were used for identification of the cry1 genes by PCR. Nevertheless, the presence of cry1 type gene(s) in B. thuringiensis INTA 51-3 was confirmed. Highly concentrated crystal suspensions showed to be weakly toxic only to lepidopteran species.