Transcription of the Escherichia coli lac repressor gene (lacI) in vivo produces monocistronic mRNAs with discrete 3' ends in the lac control region, although the DNA sequence of this region does not specify a strong termination signal of the traditional form. Direct analysis of lac transcripts was used to show that the DNA sequence alone does not provide the signal to end the repressor mRNA and to establish that of the proteins with specific binding sites on control region DNA only the lac repressor has a striking effect on the continuity of lacI gene transcription. RNAs with 3' ends in the control region sequence are major mRNA species produced from a repressor-bound template, reflecting as much as a 50-fold increase over their levels in the repressor's absence. Repressor binding to the operator thus has a dual function. In addition to blocking initiation of transcription from the lacZ promoter, repressor serves as a termination factor by setting the length of its own transcript and separating lacI and lacZYA into two distinct transcription units.
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http://dx.doi.org/10.1073/pnas.84.10.3199 | DOI Listing |
Scand J Prim Health Care
January 2025
Unit of Physiotherapy, Department of Health and Rehabilitation, Institute of Neuroscience and Physiology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
Research has shown that physical activity on prescription (PAP), used in Swedish healthcare, increases patients' physical activity, but data are lacking regarding the long-term effects of PAP on exercise capacity. Therefor exercise capacity was evaluated in patients with metabolic risk factors, after 4.5 years of PAP treatment provided by physiotherapists in primary healthcare.
View Article and Find Full Text PDFSupport Care Cancer
January 2025
Department of Nursing, Nanfang Hosptial of Southern Medical University, Guangzhou, 510515, People's Republic of China.
Purpose: Our study aim was to understand the (human and organizational) factors influencing fall risk among people with hematological malignancies using the Reason model as a framework, providing insights that can inform the development of safe and effective fall management strategies.
Methods: Purposive sampling was employed to conduct semi-structured interviews with 13 people with hematological malignancies and 12 nurses from the hematology department of a tertiary grade A hospital in Guangzhou from December 2023 to February 2024. The topic analysis method was utilized to analyze the interview data.
Jpn J Radiol
January 2025
Department of Obstetrics and Gynecology, Graduate School of Biomedical Sciences, Hiroshima University, Hiroshima, Japan.
Purpose: This study aimed to investigate whether vitamin K (menatetrenone) suppresses bone mineral density (BMD) loss in the irradiated region after radiotherapy (RT) in uterine cancer patients.
Materials And Methods: Our study included 34 patients who underwent whole pelvic irradiation for uterine cancer between 2001 and 2010. The patients were categorized in two groups: (1) Vitamin K (45 mg/day) administration group (group A) with 18 cases and (2) non-administered group (group B) with 16 cases.
Neotrop Entomol
January 2025
Research Center for Family Agriculture, Agricultural Research and Rural Extension Company of Santa Catarina (CEPAF/EPAGRI), Chapecó, Santa Catarina, Brazil.
To understand the interactions of entomopathogenic fungi with forage plants and their influence on associated herbivorous, we evaluated the influence of endophytic colonization with three isolates (CEPAF_ENT 25, CEPAF_ENT 27, and IBCB 425) of Metarhizium anisopliae on Cynodon dactylon, regarding the biological and behavioral aspects of Collaria scenica, an emerging sucking pest in pastoral systems in Brazil. The application of suspensions at the base of plant (drench) was effective in promoting endophytic colonization, especially in the roots, with emphasis on isolates CEPAF_ENT25 and CEPAF_ENT27. Despite the significant reduction in damage caused by C.
View Article and Find Full Text PDFSci Rep
January 2025
Department of Respiratory medicine, Taian 88 Hospital, Taian, 271000, People's Republic of China.
Recent empirical investigations reinforce the understanding of a profound interconnection between metabolic functions and Obstructive Sleep Apnea-hypopnea Syndrome (OSAHS). This study identifies distinctive miRNA signatures in OSAHS with Metabolic Syndrome (Mets) patients from healthy subjects, that could serve as diagnostic biomarkers or describe differential molecular mechanisms with potential therapeutic implications. In this study, OSAHS with MetS patients showed significantly higher Apnea Hyponea Index(AHI), but lower oxygen desaturation index(ODI 4/h) and minimum pulse oxygen saturation(SpO).
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