Production of therapeutic iduronate-2-sulfatase enzyme with a novel single-stranded RNA virus vector.

The Sendai virus vector has received a lot of attention due to its broad tropism for mammalian cells. As a result of efforts for genetic studies based on a mutant virus, we can now express more than 10 genes of up to 13.5 kilo nucleotides in a single vector with high protein expression efficiency. To prove this benefit, we examined the efficacy of the novel ribonucleic acid (RNA) virus vector harboring the human iduronate-2-sulfatase (IDS) gene with 1,653 base pairs, a causative gene for mucopolysaccharidosis type II, also known as a disorder of lysosomal storage disorders. As expected, this novel RNA vector with the human IDS gene exhibited its marked expression as determined by the expression of enhanced green fluorescent protein and IDS enzyme activity. While these cells exhibited a normal growth rate, the BHK-21 transformant cells stably expressing the human IDS gene persistently generated an active human IDS enzyme extracellularly. The human IDS protein produced failed to be incorporated into the lysosome when cells were pretreated with mannose-6-phosphate, demonstrating that this human IDS enzyme has potential for therapeutic use by cross-correction. These results suggest that our novel RNA vector may be applicable for further clinical settings.

Three Cases of Chemical Burns Caused Due to Dimethyl Sulfate Poisoning.

Dimethyl sulfate (DMS) is a drug widely used as a pharmaceutical and synthetic raw material. On the other hand, it is highly toxic and requires management and treatment as a hazardous substance. A mass outbreak of chemical burns resulting from DMS poisoning occurred at a drug factory. All three patients were brought to our hospital, a tertiary emergency medical facility, several hours after exposure. Their vital signs were stable, with only eye pain and a sore throat. However, after admission, two patients required emergency tracheostomy or endotracheal intubation due to laryngeal edema. Improvement was achieved through the administration of steroids, but a severely injured patient required an extended treatment period. DMS poisoning is rare; however, it can be fatal depending on the exposure concentration. Furthermore, even if the initial symptoms are mild, laryngeal edema may develop later, requiring careful monitoring and appropriate airway interventions.

Takotsubo cardiomyopathy triggered by frequent psychogenic nonepileptic seizures: A case report.

Background: Coexistence of Takotsubo cardiomyopathy and psychogenic nonepileptic seizures has rarely been reported. Herein, we report a case of Takotsubo cardiomyopathy triggered by psychogenic nonepileptic seizures. Case Presentation: A 50-year-old woman with a 22-year history of dissociative and panic disorders and a 7-year history of seizures increasing in frequency was admitted due to cardiogenic shock. Based on the left ventriculography and electroencephalography findings, she was diagnosed with Takotsubo cardiomyopathy and psychogenic nonepileptic seizures. Seizures were controlled using antipsychotic agents, resulting in improved cardiac function, and she was discharged. However, she died of cardiopulmonary arrest 9 days after discharge. Conclusion: Since controlling psychogenic epileptic seizures is difficult, Takotsubo cardiomyopathy triggered by psychogenic nonepileptic seizures may have poor prognosis, requiring careful management and close monitoring.

Prognosis and Characteristics of Hypermucoviscous Klebsiella pneumoniae Infection in Critically Ill Patients: A Case Series.

Introduction Hypermucoviscous Klebsiella pneumoniae (hvKP) is related to invasive infections; however, there have been very few comprehensive reports on the clinical features and prognosis of critically ill patients with the infection. Methods We conducted a retrospective case series in a general intensive care unit in Japan. Patients with positive blood cultures for KP between January 1, 2020 and December 31, 2022 were included. hvKP was defined by the positivity in the string test. We analyzed the patient's characteristics at baseline, including comorbidities, abscess formation, Sequential Organ Failure Assessment (SOFA) score, Acute Physiology and Chronic Health Evaluation (APACHE) II score, septic shock, duration of hospitalization, 30-day mortality, and infection site. Results A total of 24 patients had a positive blood culture for KP; nine patients (37.5%) were positive for the string test (hvKP) while 15 (62.5%) were negative (non-hvKP). In both groups, the patients were old (mean age, hvKP 80.4 vs. non-hvKP 75.7 years) and more often male (five patients (55.6%) vs. 12 patients (80.0%)). No statistically significant difference was found between the two groups in terms of comorbidities, such as diabetes mellitus, chronic obstructive pulmonary disease, chronic kidney disease, and malignancy. No statistical difference was seen in abscess formation (two patients [22.2%] vs. one patient (6.7%)), SOFA score (5.2±4.8 vs. 4.7±3.4), APACHE II score (19.6 (15.0-20.0) vs. 17.0 (11.2-20.8)), septic shock (five patients (55.6%) vs. four patient (26.7%)), duration of hospitalization (37.2 (12.0-51.0) vs. 32.3 (9.5-21.0)), and 30-day mortality (two patients (22.2%) vs. two patients (13.3%)). Two cases with hvKP died within 24 h. No significant difference was seen in the infection sources; respiratory infection (2 (22.2%) vs. 1 (6.7%)), hepatobiliary infection (2 (22.2%) vs. 7 (46.7%)), and genitourinary infection (1 (11.1%) vs. 5 (33.3%)). Conclusions Critically ill patients with hvKP infection showed characteristics similar to those reported previously. However, the disease could rapidly become severe and have a poor prognostic outcome.

Severe Duodenal Bleeding with Heterotaxy Syndrome Controlled by Combined Hemostatic Strategies: A Case Report.

A 73-year-old man with a history of heterotaxy syndrome and intestinal malrotation developed hemorrhagic shock due to bleeding from a duodenal ulcer. Esophagogastroduodenoscopy failed to achieve hemostasis because of restriction of the view by massive hemorrhage. Transcatheter arterial embolization cannot achieve endovascular hemostasis due to the vascular anatomy. Therefore, surgical hemostasis was achieved. Intestinal malrotation due to heterotaxy syndrome is a risk factor for gastrointestinal bleeding. Severe gastrointestinal bleeding in patients with intestinal malrotation is difficult to control with endoscopy alone. Therefore, combined therapies with endoscopy, interventional radiology, surgical procedures, and intensive care are vital for achieving a better prognosis.

Metagenomic screening for bleomycin resistance genes.

A metagenomic library of activated sludge was screened for bleomycin resistance genes. Two genes were identified that differed greatly from each other, from the genes of bleomycin-producing actinomycetes, and from those of clinical isolates. Therefore, the nonclinical environment is a rich reservoir of new resistance elements, and metagenomics can be used to sample the resistome rapidly.

Diversity of extradiol dioxygenases in aromatic-degrading microbial community explored using both culture-dependent and culture-independent approaches.

Culture-dependent and culture-independent approaches were used for extensive retrieval of the extradiol dioxygenase (EDO) gene from the environment to investigate the relationship between the EDO genes from isolated bacteria and the metagenomic EDO genes from which they were isolated. In our previous study, we identified 91 fosmid clones showing EDO enzyme activity using a metagenomic approach. In the present study, we classified all these metagenome-derived EDOs and newly isolated 88 phenol-utilizing bacteria from the same sample and identified four EDO genes from them. Of these, two EDOs had amino acid sequences similar to those reported previously in aromatic-utilizing strains, and one EDO had a sequence almost identical to that of metagenomic EDOs identified in our previous study. Unexpectedly, one EDO showed no similarity to any class I EDOs and was categorized as class II, which has not been found in past metagenomic approaches. Quantitative polymerase chain reaction (PCR) assay indicated that the low-abundance class II EDO gene can be enriched by culturing approaches. We conclude that the combined use of the two approaches can explore the gene community more extensively than their individual use.

The molecular basis for adaptive evolution in novel extradiol dioxygenases retrieved from the metagenome.

Extradiol dioxygenase (EDO) catalyzes metal-dependent ring cleavage of catecholic substrates. We previously screened a metagenomic library of activated sludge used to treat industrial wastewater contaminated with phenols and cyanide to identify 43 EDO genes. Here, we have characterized the enzymes belonging to novel I.2.G, I.3.M and I.3.N subfamilies. The I.3.M and I.3.N EDOs were Fe(II) dependent and preferred bicyclic substrates, whereas the I.2.G EDOs were Mn(II) dependent, preferred monocyclic substrates and had the highest affinity for catechol reported thus far. The I.2.G EDOs were more tolerant against heat (60 degrees C for 1 h) and chemical inhibitors (H(2)O(2) and NaCN) than I.3.M and I.3.N EDOs. Considering the dominance of the I.2.G EDOs over all retrieved EDOs (20 of 43 clones) and the presence of cyanide in the environment, this high affinity for substrate and structural robustness should provide survival advantages to host microorganisms. The 20 I.2.G EDOs were classified into six groups based on the amino acid sequence of the predicted ancestor, 1A1. Enzymes were chosen from each group and characterized. Two descendents, 1D2 and 5B2, each had a k(cat)/K(M) approximately twofold higher than that of 1A1 and reduced thermal stability, suggesting that descendents of 1A1 have adapted evolutionarily by a trade-off of inherent stability for increased activity.