Evaluation of the antinociceptive activities of natural propolis extract derived from stingless bee Trigona thoracica in mice

Background

: Stingless bee propolis is a popular traditional folk medicine and has been employed since ancient times. This study aimed to evaluate the antinociceptive activities of the chemical constituents of aqueous propolis extract (APE) collected by Trigona thoracica in a nociceptive model in mice.

Methods

: The identification of chemical constituents of APE was performed using high-performance liquid chromatography (HPLC). Ninety-six male Swiss mice were administered APE (400 mg/kg, 1,000 mg/kg, and 2,000 mg/kg) before developing nociceptive pain models. Then, the antinociceptive properties of each APE dose were evaluated in acetic acid-induced abdominal constriction, hot plate test, and formalin-induced paw licking test. Administration of normal saline, acetylsalicylic acid (ASA, 100 mg/kg, orally), and morphine (5 mg/kg, intraperitoneally) were used for the experiments.

Results

: HPLC revealed that the APE from Trigona thoracica contained p-coumaric acid (R2 = 0.999) and caffeic acid (R2 = 0.998). Although all APE dosages showed inhibition of acetic acid-induced abdominal constriction, only 2,000 mg/kg was comparable to the result of ASA (68.7% vs. 73.3%, respectively). In the hot plate test, only 2,000 mg/kg of APE increased the latency time significantly compared to the control. In the formalin test, the durations of paw licking were significantly reduced at early and late phases in all APE groups with a decrease from 45.1% to 53.3%.

Conclusions

: APE from Trigona thoracica, containing p-coumaric acid and caffeic acid, exhibited antinociceptive effects, which supports its potential use in targeting the prevention or reversal of central and peripheral sensitization that may produce clinical pain conditions.

Thoracic sympathetic ganglion blocks: real-world outcomes in 207 chronic pain patients

BACKGROUND

Thoracic sympathetic ganglion block (TSGB) is a procedure to manage sympathetically maintained upper extremity pain (sympathetically maintained pain). To date, only a few studies have evaluated the clinical effectiveness of TSGB in pain medicine. This study investigated (1) the relationship between technical success of TSGB and pain reduction in patients with chronic upper extremity pain and (2) relevant clinical factors for a positive TSGB outcome.

METHODS

We retrospectively reviewed medical data in 232 patients who received TSGB from 2004 to 2020. Technical success and a positive outcome of TSGB were defined as a temperature increase of ≥1.5°C at 20 min and a pain reduction with ≥2 points on the 11-point Numerical Rating Scale at 2 weeks post-TSGB, respectively. Correlations were assessed using correlation coefficients (R), and multivariable regression model was used to identify factors relevant to TSGB outcomes.

RESULTS

207 patients were ultimately analyzed; among them, 115 (55.5%) patients positively responded to TSGB, and 139 (67.1%) achieved technical success after TSGB. No significant relationship existed between the pain reduction and the temperature increase after TSGB (R=0.013, p=0.855). Comorbid diabetes (OR 4.200) and adjuvant intake (OR 3.451) were positively associated, and psychiatric comorbidity (OR 0.327) and pain duration (OR 0.973) were negatively associated with TSGB outcome.

CONCLUSIONS

We found no significant association between the temperature increase and pain reduction after TSGB. Further studies are warranted to identify significant factors associated with TSGB outcomes in patients with complex regional pain syndrome and neuropathic pain diseases.

Managing COVID-19 Pandemic in the Community: A Primary Health Clinic Experience

The coronavirus disease 2019 (COVID-19) pandemic has affected several countries worldwide, including Malaysia, with the first reported case occurring in January 2020. Terengganu, a state on the east coast of Malaysia, is finding it challenging to contain the disease by aggressively instituting all public health measures to reduce the number of COVID-19 cases and community transmission. Our primary health clinic, which is situated in a semi-rural district in Terengganu, is also involved in the implementation of containment measures, community risk measurement, and the initial management of COVID-19 cases. The health clinic changed the clinic system for the delivery of healthcare services to avoid overcrowding of patients and adapted innovative ways of providing medical services, such as telemedicine and "drive-through" pharmacy. It also provided continuous health education and awareness regarding COVID-19 to both patients and clinic attendees. The essential element of combating the infection is the effective control of infection in a small, isolated clinic in which space and adequate facilities are known challenges. This study aimed to highlight the flow of COVID-19 management starting from screening, triaging, and management based on protocol, implementation of infection control measures, and training of healthcare workers in our health clinic. The mental health of these workers was managed by the Mental Health and Psychosocial Support Unit, as recommended by the Ministry of Health Malaysia. The role of primary care clinics in the ongoing pandemic is currently increasing. Hence, higher authority and the government must increase the number of facilities, human resources, and financial budget to ensure that all initiatives can be implemented effectively.