Mycobacterial HelD connects RNA polymerase recycling with transcription initiation.

Mycobacterial HelD is a transcription factor that recycles stalled RNAP by dissociating it from nucleic acids and, if present, from the antibiotic rifampicin. The rescued RNAP, however, must disengage from HelD to participate in subsequent rounds of transcription. The mechanism of release is unknown.

Substrate preference, RNA binding and active site versatility of Stenotrophomonas maltophilia nuclease SmNuc1, explained by a structural study.

Nucleases of the S1/P1 family have important applications in biotechnology and molecular biology. We have performed structural analyses of SmNuc1 nuclease from Stenotrophomonas maltophilia, including RNA cleavage product binding and mutagenesis in a newly discovered flexible Arg74-motif, involved in substrate binding and product release and likely contributing to the high catalytic rate. The Arg74Gln mutation shifts substrate preference towards RNA.

The Impact of COVID-19 Third Dose Vaccination on the Magnitude of Antigen Specific T Cells in Kidney Transplant Patients.

Measuring T cell response can add information about antivirus immunity provided by antibody test results. The study evaluates the impact of a third mRNA COVID-19 vaccine dose on T cell response and antibody production in kidney transplant recipients (25 KTRs) versus healthy controls (26 Hc). Results show a significant rise in S-activated CD4+CD154+IFN?+TNF?+ double producer cells in both KTRs (p=0.

Are there Risks from Nanocomposite Restoration Grinding for Dentists?

Objectives: To evaluate the effect of short-term inhalational exposure to nanoparticles released during dental composite grinding on oxidative stress and antioxidant capacity markers.

Materials And Methods: Twenty-four healthy volunteers were examined before and after exposure in dental workshop. They spent 76.

Are there any limits to the dental treatment of children?

Aim: The objective of this paper is to describe and discuss the most commonly occurring limits in care provision between a dentist and a child, i.e. provider and recipient.

Parathyroid tumors in the 5th edition of the WHO Classification of Tumors of the Endocrine Organs.

The diagnosis of pathological conditions of the parathyroid glands is the answer to clinically more frequently detected hypercalcemic conditions, including MEN syndromes. In routine biopsy practice, enlarged bodies are also a differential diagnosis for the diagnosis of thyroid nodules. In the chapter of parathyroid tumors, the 5th edition of the WHO classification brings changes influenced similarly to other endocrine organs by the increase in genetic information.

Changes in thyroid cytology reporting in the 3rd edition of the Bethesda system.

Reporting fine-needle aspiration of thyroid nodules in the Bethesda classification is a practice widely used internationally and by us. The revised third edition of the Bethesda System of Reporting Thyroid Cytopathology brings changes in terminology, content, and new chapters. In terms of terminology, an obvious change is the removal of the two-word names of three categories while maintaining the six diagnostic categories of the previous versions - new: BI - non-diag- nostic, BIII - atypia of undetermined significance, BIV - follicular neoplasia.

Hand2 Immunohistochemistry in the Diagnosis of Paragangliomas and Other Neuroendocrine Neoplasms.

Hand2 is a core transcription factor responsible for chromaffin cell differentiation. However, its potential utility in surgical pathology has not been studied. Thus, we aimed to investigate its expression in paragangliomas, other neuroendocrine neoplasms (NENs), and additional non-neuroendocrine tumors.

Cardiovascular Complications in Pheochromocytoma and Paraganglioma: Does Phenotype Matter?

Background: Adrenaline-producing tumors are mostly characterized by a sudden release of catecholamines with episodic symptoms. Noradrenergic ones are usually less symptomatic and characterized by a continuous overproduction of catecholamines that are released into the bloodstream. Their effects on the cardiovascular system can thus be different.

Clinical and molecular genetic analysis of cytologically uncertain thyroid nodules in patients with thyroid disease.

Background: The current requirement is to establish the preoperative diagnosis accurately as possible and to achieve an adequate extent of surgery. The aim of this study was to define the preoperative clinical and molecular genetic risks of malignancy in indeterminate thyroid nodules (Bethesda III and IV) and to determine their impact on the surgical strategy.

Methods: Prospectively retrospective analysis of 287 patients provided the basis of preoperative laboratory examination, sonographic stratification of malignancy risks and cytological findings.

Tetracycline-modifying enzyme SmTetX from Stenotrophomonas maltophilia.

The resistance of the emerging human pathogen Stenotrophomonas maltophilia to tetracycline antibiotics mainly depends on multidrug efflux pumps and ribosomal protection enzymes. However, the genomes of several strains of this Gram-negative bacterium code for a FAD-dependent monooxygenase (SmTetX) homologous to tetracycline destructases. This protein was recombinantly produced and its structure and function were investigated.

A highly active S1-P1 nuclease from the opportunistic pathogen Stenotrophomonas maltophilia cleaves c-di-GMP.

A number of multidrug-resistant bacterial pathogens code for S1-P1 nucleases with a poorly understood role. We have characterized a recombinant form of S1-P1 nuclease from Stenotrophomonas maltophilia, an opportunistic pathogen. S.

The importance of lung biopsy in a patient with idiopathic pulmonary fibrosis: a case report.

Idiopathic pulmonary fibrosis (IPF) is a severe progressive fibrotic disease of the lung. Its etiology is not yet completely clear. The affected population is exclusively older than 40 years with maximum incidence in the age categories of 60 to 70 years.

Dental fear/anxiety in Czech preschoolers: relationship to gender, age, location of residence, dental status and previous treatment experience.

Aim: Dental fear/anxiety (DFA) may considerably complicate treatment in paediatric dentistry. This cross-sectional study aimed to assess DFA in Czech preschoolers aged 3-6 years and its relationship to gender, age, location of residence, dental status and previous treatment.

Methods: The study involved 460 children from preschools in four location types selected according to the WHO criteria for oral health surveys.

Metal hypersensitivity and pro-inflammatory cytokine production in patients with failed orthopedic implants: A case-control study.

Orthopedic implants heal well without complications in most patients but fail for unclear reasons in some individuals. This study determined the relevance of metal hypersensitivity in patients with failed orthopedic implants and those requiring orthopedic implant surgery. The study included 35 patients with failed orthopedic implants and 15 subjects scheduled for orthopedic implant surgery.

Atomic resolution studies of S1 nuclease complexes reveal details of RNA interaction with the enzyme despite multiple lattice-translocation defects.

S1 nuclease from Aspergillus oryzae is a single-strand-specific nuclease from the S1/P1 family that is utilized in biochemistry and biotechnology. S1 nuclease is active on both RNA and DNA but with differing catalytic efficiencies. This study clarifies its catalytic properties using a thorough comparison of differences in the binding of RNA and DNA in the active site of S1 nuclease based on X-ray structures, including two newly solved complexes of S1 nuclease with the products of RNA cleavage at atomic resolution.

The first structure-function study of GH151 α-l-fucosidase uncovers new oligomerization pattern, active site complementation, and selective substrate specificity.

Fucosylated compounds are abundantly present in nature and are associated with many biological processes, therefore carrying great potential for use in medicine and biotechnology. Efficient ways to modify fucosylated compounds are still being developed. Promising results are provided by glycosyl hydrolases with transglycosylating activities, such as α-l-fucosidase isoenzyme 2 from Paenibacillus thiaminolyticus (family GH151 of Carbohydrate-Active enZYmes).

TREATMENT OPTIONS FOR PREMACULAR AND SUB-INTERNAL LIMITING MEMBRANE HEMORRHAGE.

Introduction: Premacular hemorrhage (PH) and sub-internal limiting membrane hemorrhage (sub-ILM-H) are among the causes of sudden deterioration of central visual acuity. Anatomical and functional outcomes of different therapeutic options were evaluated retrospectively.

Methods: The study included three eyes of three patients (2 females and 1 male).

A Complex Evaluation of the In-Vivo Biocompatibility and Degradation of an Extruded ZnMgSr Absorbable Alloy Implanted into Rabbit Bones for 360 Days.

The increasing incidence of trauma in medicine brings with it new demands on the materials used for the surgical treatment of bone fractures. Titanium, its alloys, and steel are used worldwide in the treatment of skeletal injuries. These metallic materials, although inert, are often removed after the injured bone has healed.

Chitinase Chit62J4 Essential for Chitin Processing by Human Microbiome Bacterium J4.

Commensal bacterium J4 produces several extracellular chitinolytic enzymes including a 62 kDa chitinase Chit62J4 active toward 4-nitrophenyl ,'-diacetyl-β-d-chitobioside (pNGG). We characterized the crude enzyme from bacterial culture fluid, recombinant enzyme rChit62J4, and its catalytic domain rChit62J4cat. This major chitinase, securing nutrition of the bacterium in the human intestinal tract when supplied with chitin, has a pH optimum of 5.

Postoperative adrenal insufficiency in Conn's syndrome-does it occur frequently?

Primary aldosteronism (PA) is the most frequent form of endocrine hypertension. Recently, frequent clinically significant adrenal insufficiency after adrenalectomy in subjects with PA has been reported, which may make the early postsurgical management difficult. We retrospectively searched for possible adrenal insufficiency in subjects who underwent adrenalectomy for PA and have measured cortisol in the early postoperative course.

Total thyroidectomy can still remain the method of choice in some Bethesda III cases.

Background: The latest WHO classification of tumours of endocrine organs defines new units of borderline thyroid tumours (BTT). The aim of our study was to evaluate ultrasonographic and cytological features, mutation profile and surgery treatment in rare thyroid tumours.

Methods: An analysis of 8 BTT out of 487 patients, who underwent thyroid surgery between June 2016 and June 2020.

Zn-0.8Mg-0.2Sr (wt.%) Absorbable Screws-An In-Vivo Biocompatibility and Degradation Pilot Study on a Rabbit Model.

In this pilot study, we investigated the biocompatibility and degradation rate of an extruded Zn-0.8Mg-0.2Sr (wt.