A Case of Pulmonary Hypertension in a 67-Year-Old Woman with Thiamine Deficiency Following Partial Gastrectomy and Exacerbated by Diuretics.

BACKGROUND Thiamine deficiency often occurs in patients with alcohol abuse and unbalanced diets. However, gastric surgery and/or use of diuretics can also cause this situation. Importantly, thiamine deficiency can cause pulmonary hypertension, which is completely reversible. This report is of a case of a 67-year-old woman who presented with pulmonary hypertension and thiamine deficiency following partial gastrectomy and exacerbated by diuretics. CASE REPORT A 67-year-old woman with histories of partial gastrectomy because of non-Hodgkin lymphoma (at age 36 years) and sigmoid colectomy because of colon cancer (at age 58 years) presented with bilateral leg edema and dyspnea on exertion. Electrocardiography and right heart catheterization revealed pulmonary hypertension. Despite diuretic administration (initially indapamide, then changed to torsemide), the symptoms gradually worsened. Although she was neither an alcohol drinker nor a fussy eater, we found that her blood thiamine concentration was extremely low. We diagnosed her as having thiamine deficiency caused by gastrectomy and administered diuretics. After intravenous thiamine administration, her symptoms showed immediate improvement, associated with the normalization of the pulmonary hypertension. After detailed analysis of the cause of her pulmonary hypertension, including Swan-Ganz catheterization and echocardiography, we concluded that her pulmonary hypertension was caused by thiamine deficiency following partial gastrectomy and exacerbated by diuretics. CONCLUSIONS This case highlights the importance of recognizing that thiamine deficiency can be a cause of pulmonary hypertension, and that thiamine deficiency can be associated with gastrectomy and the use of diuretics.

Characterization of a (D)-stereoselective aminopeptidase (DamA) exhibiting aminolytic activity and halophilicity from Aspergillus oryzae.

ß-Aminopeptidases exhibit both hydrolytic and aminolytic (peptide bond formation) activities and have only been reported in bacteria. We identified a gene encoding the ß-aminopeptidase homolog from a genome database of the filamentous fungus Aspergillus oryzae. The gene was overexpressed in A. oryzae, and the resulting recombinant enzyme was purified. Apart from bacterial homologs [ß-Ala-para-nitroanilide (pNA)], the enzyme preferred D-Leu-pNA and D-Phe-pNA as substrates. Therefore, we designated this gene as d-stereoselective aminopeptidase A (damA). The purified recombinant DamA was estimated to be a hexamer and was composed of two subunits with molecular masses of 29.5 and 11.5 kDa, respectively. Optimal hydrolytic activity of DamA toward D-Leu-pNA was observed at 50 °C and pH 8.0. The enzyme was stable up to 60 °C and from pH 4.0-11.0. DamA also exhibited aminolytic activity, producing D-Leu-D-Leu-NH2 from D-Leu-NH2 as a substrate. In the presence of 3.0 M NaCl, the amount of pNA liberated from D-Leu-pNA by DamA was 3.1-fold higher than that in the absence of NaCl. Thus, DamA is a halophilic enzyme. The enzyme was utilized to synthesize several hetero-dipeptides containing a D-amino acid at the N-terminus as well as physiologically active peptides.

Deodorization and dewatering of biosolids by using dimethyl ether.

We proposed a method for the deodorising and dewatering of biosolids. In the proposed method, liquefied dimethyl ether (DME) was used as an extractant for odorous components and water. We developed a bench-scale experiment to almost completely deodorize and dewater biosolids by using liquefied DME at room temperature. The deodorized and dewatered biosolids have sufficient caloric density and can be used as a carbon neutral fuel.

Characterization of an Aspergillus oryzae cysteinyl dipeptidase expressed in Escherichia coli.

Cysteinyl dipeptidase from Aspergillus oryzae (CdpA) was produced in Escherichia coli and purified. The enzyme showed activity specific toward cysteine-containing dipeptides, but its substrate specificity was distinct from those of other cysteinyl dipeptidases of the M20 family. It was optimally active at pH 7-8 and stable at pH 6-9 and at up to 40 °C.