The extent of hypoxic regions in a tumor tissue depends on the arrangement, blood flow rate and blood oxygen content of microvessels, and on the tissue's oxygen consumption rate. Here, the effects of blood flow rate, blood oxygen content and oxygen consumption on hypoxic fraction are simulated theoretically, for a region whose microvascular geometry was derived from observations of a transplanted mammary andenocarcinoma (R3230AC) in a rat dorsal skin flap preparation. In the control state, arterial PO2 is 100 mmHg, consumption rate is 2.4 cm3 O2/100 g/min, and hypoxic fraction (tissue with PO2 < 3 mmHg) is 30%. Hypoxia is abolished by a reduction in consumption rate of at least 30%, relative to control, or an increase in flow rate by a factor of 4 or more, or an increase in arterial PO2 by a factor of 11 or more. These results suggest that reducing oxygen consumption rate may be more effective than elevating blood flow or oxygen content as a method to reduce tumor hypoxia.

Download full-text PDF

Source
http://dx.doi.org/10.3109/02841869509093981DOI Listing

Publication Analysis

Top Keywords

consumption rate
16
hypoxic fraction
12
blood flow
12
flow rate
12
oxygen content
12
oxygen consumption
12
rate blood
8
blood oxygen
8
arterial po2
8
oxygen
7

Similar Publications

Aims: To assess the evidence for a relationship between the use of e-cigarettes and subsequent smoking in young people (≤29 years), and whether this differs by demographic characteristics.

Methods: Systematic review with association direction plots (searches to April 2023). Screening, data extraction and critical appraisal followed Cochrane methods.

View Article and Find Full Text PDF

Ammonia (NH) is esteemed for its attributes as a carbon-neutral fuel and hydrogen storage material, due to its high energy density, abundant hydrogen content, and notably higher liquefaction temperature in comparison to hydrogen gas. The primary method for the synthetic generation of NH is the Haber-Bosch process, involving rigorous conditions and resulting in significant global energy consumption and carbon dioxide emissions. To tackle energy and environmental challenges, the exploration of innovative green and sustainable technologies for NH synthesis is imperative.

View Article and Find Full Text PDF

A survey on the implementation of family doctor contract services in China from the perspective of resident demand.

Fam Pract

January 2025

College of Civil Engineering, Tongji University, No. 1239, Siping Road, Yangpu District, Shanghai 200092, China.

Background: To understand the implementation of the family doctor contract service system in China from the perspective of resident demand.

Methods: A stratified random sampling design was employed to survey 6380 residents across the eastern, central, and western regions of China. Data were processed using SPSS 22.

View Article and Find Full Text PDF

HO Triggering Electron-Directed Transfer of Emerging Contaminants over Asymmetric Nano Zinc Oxide Surfaces for Water Self-Purification Expansion.

JACS Au

January 2025

Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Institute of Environmental Research at Greater Bay, Guangzhou University, Guangzhou 510006, China.

Slow mass transfer processes between inert emerging contaminants (ECs) and dissolved oxygen (DO) limit natural water self-purification; thus, excessive energy consumption is necessary to achieve ECs removal, which has become a longstanding global challenge. Here, we propose an innovative water self-purification expansion strategy by constructing asymmetric surfaces that could modulate trace HO as trigger rather than oxidant to bridge a channel between inert ECs and natural dissolved oxygen, achieved through a dual-reaction-center (DRC) catalyst consisting of Cu/Co lattice-substituted ZnO nanorods (CCZO-NRs). During water purification, the bond lengths of emerging contaminants (ECs) adsorbed on the asymmetric surface were stretched, and this stretching was further enhanced by HO mediation, resulting in a significant reduction of bond-breaking energy barriers.

View Article and Find Full Text PDF

Introduction: Colorectal cancer (CRC) is characterized by an extremely high mortality rate, mainly caused by the high metastatic potential of this type of cancer. To date, chemotherapy remains the backbone of the treatment of metastatic colorectal cancer. Three main chemotherapeutic drugs used for the treatment of metastatic colorectal cancer are 5-fluorouracil, oxaliplatin and irinotecan which is metabolized to an active compound SN-38.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!