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01 Dec 2020
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Dr. Hsu Li Yang, Dr. Tan Thuan Tong, Dr. Andrea Kwa, 08 Jan 2021
Antimicrobial resistance has become increasingly dire as the rapid emergence of drug resistance, especially gram-negative pathogens, has outpaced the development of new antibiotics. At a recent virtual symposium, Dr Hsu Li Yang, Vice Dean (Global Health) and Programme Leader (Infectious Diseases), NUS Saw Swee Hock School of Public Health, presented epidemiological data on multidrug-resistant (MDR) gram-negative bacteria (GNB) in Asia, while Dr Tan Thuan Tong, Head and Senior Consultant, Department of Infectious Diseases, Singapore General Hospital (SGH), focused on the role of ceftazidime-avibactam in MDR GNB infections. Dr Andrea Kwa, Assistant Director of Research, Department of Pharmacy, SGH, joined the panel in an interactive fireside chat, to discuss challenges, practical considerations, and solutions in MDR gram-negative infections. This Pfizer-sponsored symposium was chaired by Dr Ng Shin Yi, Head and Senior Consultant of Surgical Intensive Care, SGH.
Pearl Toh, 26 Nov 2020
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Cannabis has ceiling concentration for efficacy

14 Dec 2020

Tetrahydrocannabinol (THC) is effective in reducing pain, but only up to a certain plasma concentration, beyond which it appears to magnify pain, according to a new study.

Over four sessions, each separated by 2 weeks, 16 patients with painful diabetic neuropathy were randomly assigned to one of four conditions: placebo or low (1% THC), medium (4% THC), or high (7% THC) doses of cannabis. Blood samples were drawn periodically and plasma levels of THC were measured using gas chromatography-mass spectrometry.

Researchers found significant linear and curvilinear effects of THC concentration, indicating that pain does indeed change as a function of THC (p≤0.001). THC estimates were negative, suggesting that, in general, pain was inversely correlated to THC concentration.

On the other hand, THC2 estimates were positive, indicative of a U-shaped relationship, such that pain is greatest at the extremes of THC concentration.

Johnson-Neyman estimates further pinpointed a THC threshold value of approximately 16 ng/mL. Below this, the slope of the interaction between THC and spontaneous pain was negative and significant (estimate, –0.04, 95 percent confidence interval [CI], –0.08 to 0.00). As plasma THC levels approached 16 ng/mL, pain became increasingly subdued.

Beyond the threshold value, however, the slope flipped, returning a positive estimate (0.09, 95 percent CI, 0.00–0.18), suggesting that at higher THC values, pain response was instead intensified.

“These findings are clinically important and stress the need for studies evaluating the plasma concentration-response effects of THC on pain. These data also suggest that the continuing trend for the cultivation of cannabis with higher levels of THC may paradoxically lead to a worsening of pain outcomes,” the researchers said.

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Most Read Articles
01 Dec 2020
Tetanus toxoid 5 Lf, diphtheria toxoid 2 Lf, pertussis toxoid 2.5 mcg, filamentous haemagglutinin 5 mcg, fimbriae types 2 and 3 5 mcg, pertactin 3 mcg
Dr. Hsu Li Yang, Dr. Tan Thuan Tong, Dr. Andrea Kwa, 08 Jan 2021
Antimicrobial resistance has become increasingly dire as the rapid emergence of drug resistance, especially gram-negative pathogens, has outpaced the development of new antibiotics. At a recent virtual symposium, Dr Hsu Li Yang, Vice Dean (Global Health) and Programme Leader (Infectious Diseases), NUS Saw Swee Hock School of Public Health, presented epidemiological data on multidrug-resistant (MDR) gram-negative bacteria (GNB) in Asia, while Dr Tan Thuan Tong, Head and Senior Consultant, Department of Infectious Diseases, Singapore General Hospital (SGH), focused on the role of ceftazidime-avibactam in MDR GNB infections. Dr Andrea Kwa, Assistant Director of Research, Department of Pharmacy, SGH, joined the panel in an interactive fireside chat, to discuss challenges, practical considerations, and solutions in MDR gram-negative infections. This Pfizer-sponsored symposium was chaired by Dr Ng Shin Yi, Head and Senior Consultant of Surgical Intensive Care, SGH.
Pearl Toh, 26 Nov 2020
Inhaled corticosteroid (ICS) should be the mainstay of long-term asthma management — such is the key message of the latest Singapore ACE* Clinical Guidance (ACG) for asthma, released in October 2020.
2 days ago
Among patients with moderate-to-severe psoriasis, the use of biologics appears to lower the risk of being hospitalized for the novel coronavirus disease (COVID-19), a new study has found.