Gastroesophageal reflux disease in the older patient: presentation, treatment, and complications

Gastroesophageal reflux disease (GERD) is common in the elderly. Patients often complain of less severe or frequent heartburn than their younger cohorts, but because of prolonged acid exposure over many years, the elderly have more complicated reflux disease including esophagitis, peptic strictures, and Barrett's esophagus. Potential factors aggravating GERD in the elderly include medications, which reduce lower esophageal sphincter pressure, higher frequency of hiatal hernia, impaired motility, and decreased saliva volume and bicarbonate concentration. Early endoscopy is indicated in all elderly patients with GERD, regardless of symptom severity. The medical and surgical treatment of GERD in the elderly generally follows the same principles as for any adult patient.     

Bcr/abl+ autologous dendritic cells for vaccination in chronic myeloid leukemia

In chronic myeloid leukemia (CML) ex vivo generated DC are characterized by constitutive expression of bcr/abl and possibly other yet undefined leukemia-associated antigens, since these DC share a common progeny with leukemic cells. Induction of anti-leukemic T cell responses has been described in vitro. For a phase I vaccination study, autologous bcr/abl+ DC are generated under GMP conditions mainly from monocyte precursors in chronic phase CML patients. Lin-, CD80+, CD86+, CD83+, DR+ DC could be generated in sufficient numbers for s.c. vaccination with 1 x 10(6)-5 x 10(7) DC. Using monocyte precursors, the yield of DC per seeded PBMC was in the range of 1-6%. Furthermore, we could demonstrate in vitro that the T cell stimulatory ability of CD34+-derived DC can be augmented by a factor 2-3 by retroviral transduction with a gene coding for interleukin-7. DC-based vaccination strategies are a promising clinical approach, particularly as postremission immunotherapy in the setting of autologous stem cell transplantation.     

Isolated pituitary granuloma by atypical Mycobacterium in a nonimmunosuppressed woman

A 32-year-old woman presented with a 10-day history of fever (38.0 degrees C), headaches, nausea, vomiting and a 6-month history of diabetes insipidus and amenorrhoea. Two months previously she had undergone a surgical drilling of the right mastoid area because of mastoiditis. Endocrine investigation showed elevated serum prolactin levels, secondary adrenal and gonadal failure and a normal thyroid function. Cranial MRI scan revealed a contrast enhancing intrasellar mass (approximately 2 cm) of heterogeneous appearance with suprasellar extension and thickening of the pituitary stalk. Lumbar puncture was suggestive of aseptic meningitis. The Ziehl-Neelsen stain of cerebrospinal fluid (CSF) and the tuberculin skin test were both negative. The pituitary mass was removed with a transsphenoidal approach. Histological examination demonstrated destruction of the adenohypophysis by epithelioid granulomas with partial caseous necrosis and microabscess formation, suggestive of a mycobacterial infection. A polymerase chain reaction analysis performed on paraffin-embedded tissue was positive for mycobacterial DNA. According to the individual 16S sequence, it was identified as Mycobacterium malmoense, an atypical nontuberculous mycobacterium (NTM). In conclusion, this is the first case of an isolated pituitary granuloma caused by an NTM infection in a nonimmunosuppressed patient.     

Stringent factor from Escherichia coli directs ribosomal binding and release of uncharged tRNA.

Uncharged tRNA is preferentially bound to the peptidyl site of the ribosome in the absence of stringent factor ,but in its presence is directed to the acceptor site. The synthesis of pppGpp and ppGpp is initiated by tRNA bound in the acceptor but not in the peptidyl site. In this reaction, tRNA is not permanently attached to the acceptor site. Uncharged [32P] tRNA but not 3H-labeled stringent factor is released from the ribosome after each round of stringent factor-dependent hydrolysis of ATP. ATP-32PPi-exchange experiments reveal that exchange is independent of the presence of GTP but strongly enhanced by the addition of stringent factor and tRNA. The tRNA release is suppressed when ATP is replaced by beta, gamma-imido adenosine 5'-triphosphate, 5'-AMP, or GTP.     

Immunological identification of a common precursor to arginine vasopressin and neurophysin II synthesized by in vitro translation of bovine hypothalamic mRNA

mRNA from membrane-bound polysomes of bovine hypothalamus was translated in an mRNA-dependent cell-free system from reticulocyte lysate or wheat germ. The translation products were identified by immunoprecipitation with antibodies to either neurophysin II or arginine vasopressin followed by sodium dodecyl sulfate/polyacrylamide gel electrophoresis. An immunoreactive polypeptide was obtained with an apparent Mr of 21,000. Sequential immunoprecipitation studies indicated that the Mr 21,000 product is a common precursor to neurophysin II and arginine vasopressin. The specificity of the immunoprecipitation was demonstrated by competition with excess amounts of unlabeled neurophysin II or arginine vasopressin; little or no competition was observed with unlabeled neurophysin II or arginine vasopressin; little or no competition was observed with unlabeled neurophysin I or oxytocin. Processing experiments with microsomal membranes from dog pancreas or tunicamycin-treated ascites tumor cells showed that the Mr 21,000 polypeptide is the prepro form. It was converted to a pro form with Mr 19,000 suggesting a pre sequence of approximately 15 amino acids. The Mr 19,000 polypeptide was coreglycosylated to an apparent Mr of 23,000, indicating that the neurophysin II-arginine vasopressin precursor is a glycopolypeptide.     

Vaccine Protection against Bacillus cereus-Mediated Respiratory Anthrax-Like Disease in Mice

Bacillus cereus strains harboring a pXO1-like virulence plasmid cause respiratory anthrax-like disease in humans, particularly in welders. We developed mouse models for intraperitoneal as well as aerosol challenge with spores of B. cereus G9241, harboring pBCXO1 and pBC218 virulence plasmids. Compared to wild-type B. cereus G9241, spores with a deletion of the pBCXO1-carried protective antigen gene (pagA1) were severely attenuated, whereas spores with a deletion of the pBC218-carried protective antigen homologue (pagA2) were not. Anthrax vaccine adsorbed (AVA) immunization raised antibodies that bound and neutralized the pagA1-encoded protective antigen (PA1) but not the PA2 orthologue encoded by pagA2. AVA immunization protected mice against a lethal challenge with spores from B. cereus G9241 or B. cereus Elc4, a strain that had been isolated from a fatal case of anthrax-like disease. As the pathogenesis of B. cereus anthrax-like disease in mice is dependent on pagA1 and PA-neutralizing antibodies provide protection, AVA immunization may also protect humans from respiratory anthrax-like death.     

Evaluation of the Verigene Gram-Positive Blood Culture Nucleic Acid Test for Rapid Detection of Bacteria and Resistance Determinants

Rapid identification of pathogens from blood cultures can decrease lengths of stay and improve patient outcomes. We evaluated the accuracy of the Verigene Gram-positive blood culture (BC-GP) nucleic acid test for investigational use only (Nanosphere, Inc., Northbrook, IL) for the identification of Gram-positive bacteria from blood cultures. The detection of resistance genes (mecA in Staphylococcus aureus and Staphylococcus epidermidis and vanA or vanB in Enterococcus faecium and Enterococcus faecalis) by the BC-GP assay also was assessed. A total of 186 positive blood cultures (in BacT/Alert FA bottles) with Gram-positive cocci observed with Gram staining were analyzed using the BC-GP assay. The BC-GP results were compared with the identification and susceptibility profiles obtained with routine methods in the clinical laboratory. Discordant results were arbitrated with additional biochemical, cefoxitin disk, and repeat BC-GP testing. The initial BC-GP organism identification was concordant with routine method results for 94.6% of the blood cultures. Only 40% of the Streptococcus pneumoniae identifications were correct. The detection of the mecA gene for 69 blood cultures with only S. aureus or S. epidermidis was concordant with susceptibility testing results. For 3 of 6 cultures with multiple Staphylococcus spp., mecA detection was reported but was correlated with oxacillin resistance in a species other than S. aureus or S. epidermidis. The detection of vanA agreed with susceptibility testing results for 45 of 46 cultures with E. faecalis or E. faecium. Comparison of the mean times to results for each organism group showed that BC-GP results were available 31 to 42 h earlier than phenotypic identifications and 41 to 50 h earlier than susceptibility results.     

Evaluation of Pneumococcal Serotyping by Multiplex PCR and Quellung Reactions

Screening of 1,750 pneumococcal isolates for common serotypes by PCR was followed by Quellung reaction analysis of PCR-negative isolates with a comparison to the conventional (Quellung reaction only) approach. PCR agreed with Quellung reaction results for 99% of isolates. The sequential PCR/Quellung reaction algorithm is accurate and more cost-effective than the conventional approach.     

Identification of Enterobacteriaceae by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using the VITEK MS system

This multicenter study evaluated the accuracy of matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry identifications from the VITEK MS system (bioMérieux, Marcy l’Etoile, France) for Enterobacteriaceae typically encountered in the clinical laboratory. Enterobacteriaceae isolates (n?=?965) representing 17 genera and 40 species were analyzed on the VITEK MS system (database v2.0), in accordance with the manufacturer’s instructions. Colony growth (≤72 h) was applied directly to the target slide. Matrix solution (α-cyano-4-hydroxycinnamic acid) was added and allowed to dry before mass spectrometry analysis. On the basis of the confidence level, the VITEK MS system provided a species, genus only, or no identification for each isolate. The accuracy of the mass spectrometric identification was compared to 16S rRNA gene sequencing performed at MIDI Labs (Newark, DE). Supplemental phenotypic testing was performed at bioMérieux when necessary. The VITEK MS result agreed with the reference method identification for 96.7 % of the 965 isolates tested, with 83.8 % correct to the species level and 12.8 % limited to a genus-level identification. There was no identification for 1.7 % of the isolates. The VITEK MS system misidentified 7 isolates (0.7 %) as different genera. Three Pantoea agglomerans isolates were misidentified as Enterobacter spp. and single isolates of Enterobacter cancerogenus, Escherichia hermannii, Hafnia alvei, and Raoultella ornithinolytica were misidentified as Klebsiella oxytoca, Citrobacter koseri, Obesumbacterium proteus, and Enterobacter aerogenes, respectively. Eight isolates (0.8 %) were misidentified as a different species in the correct genus. The VITEK MS system provides reliable mass spectrometric identifications for Enterobacteriaceae.