Women in the Medical Physics Workforce: Insights from Membership Trends of the American Association of Physicists in Medicine, 1993 to 2023.

PURPOSE: Women remain underrepresented in medical physics in the United States, and determinants of persisting disparities remain unclear. Here, we performed a detailed investigation of American Association of Physicists in Medicine (AAPM) membership trajectories to evaluate trends in Full membership with respect to gender, age, and highest degree. METHODS AND MATERIALS: Membership data, including gender, date of birth, highest degree, membership type, and years of active membership for 1993 to 2023 were obtained from AAPM. Group 1 included Full members who joined AAPM in 1993 or later. A subset of group 1 including only members who joined and left AAPM since 1993 (former members, group 1F) was used to calculate age at membership cessation and duration. Results were compared by gender and highest degree. A Kaplan-Meier analysis was also used to evaluate membership "survival" by age and highest degree. RESULTS: Complete data were available for 6647 current and former Full members (group 1), including 2211 former members (group 1F). On average, women became Full members at a significantly younger age than men (34.6 vs 37.5 years of age, P < .001) and ended their memberships (if applicable) at a significantly younger age than men (46.1 vs 50.1 years of age, P < .001). The Kaplan-Meier "survival" analysis showed that for a given age, women were at a significantly greater risk of membership cessation than men, and women with master's degrees had the lowest membership survival of any gender/degree subgroup. When analyzing by membership duration, there was no difference in survival by gender alone. Still, women with PhDs were found to have the greatest membership survival among gender/degree subgroups. CONCLUSIONS: Both gender and degree type influenced AAPM membership trajectories. Although we have offered a discussion of possible explanations, qualitative data collected from both continuing and departing AAPM members will be critical in the ongoing journey toward gender parity in the profession of medical physics.

Applying formative evaluation in the mentoring of student intern nurses in an emergency department.

Objective: To explore the effectiveness of formative evaluation in the mentoring of student nursing interns in an emergency department. Methods: A total of 144 intern nursing students in the emergency department of a tertiary care hospital in Fuzhou were selected as the study subjects from July 2020 to February 2021. Adopting quasi-experimental studies methods, the students were divided into the experiment group (n = 74) and the control group (n = 70), based on their practicing rotation times. Formative evaluation methods such as in-person interviews, clinical scenario simulations, and clinical operation skills exams were conducted in the experiment group, while traditional summative evaluation methods were adopted for the control group. At the end of the intern period, a unified examination paper on professional knowledge concerning the emergency department, a cardiopulmonary resuscitation skill assessment, and a self-rating scale of self-directed learning was employed to evaluate professional theory performance, clinical practice ability, self-directed learning ability, and academic satisfaction among the nursing students, respectively. Results: The professional theoretical performance, clinical practice ability assessment scores, academic satisfaction, and self-directed learning abilities of the nursing students were significantly higher in the experiment group compared with the control group (P < 0.05). Conclusion: The application of formative evaluation during the mentoring of student intern nurses in an emergency department improved their professional theoretical performance, clinical practice skills, academic satisfaction, and self-directed learning abilities.

BACE1 gene silencing alleviates isoflurane anesthesia­induced postoperative cognitive dysfunction in immature rats by activating the PI3K/Akt signaling pathway.

Postoperative cognitive dysfunction (POCD) is a severe complication characterized by cognitive dysfunction following anesthesia and surgery. The aim of the present study was to investigate the effects of ß­site amyloid precursor protein cleavage enzyme 1 (BACE1) gene silencing on isoflurane anesthesia­induced POCD in immature rats via the phosphatidylinositol­3­kinase (PI3K)/protein kinase B (Akt) signaling pathway. Rat models were established and then transfected with BACE1 small interfering RNA and wortmannin (an inhibitor of PI3K). Blood gas analysis was performed, and a series of behavioral experiments were conducted to evaluate the cognitive function, learning ability and locomotor activity of rats. Reverse transcription quantitative polymerase chain reaction and western blot analysis were employed to determine the mRNA and protein expression of the associated genes. An ELISA was used to detect the inflammatory indicators and the content of amyloid precursor protein (APP) and amyloid­ß (Aß). Apoptosis of the hippocampal CA1 region was observed by terminal deoxynucleotidyl transferase dUTP nick­end labeling staining. Initially, it was revealed that the percentage of stagnation time in rats was increased by BACE1 gene silencing; the escape latency and swimming distance were markedly reduced from the 4th to the 6th day, the time the rats spent in first passing the target area was shortened, and the times of passing the target area were increased by BACE1 gene silencing, demonstrating that BACE1 gene silencing enhanced the spatial memory ability of rats. Additionally, it was determined that silencing BACE1 improved the pathological state induced by isoflurane anesthesia in immature rats, and attenuated the inflammatory response and the levels of APP and Aß in hippocampal tissues. Furthermore, it was suggested that silencing BACE1 may have promoted the activation of the PI3K/Akt signaling pathway, thereby inhibiting the apoptosis of the hippocampal CA1 region. Taken together, these results indicated that BACE1 gene silencing may improve isoflurane anesthesia­induced POCD in immature rats by activating the PI3K/Akt signaling pathway and inhibiting the Aß generated by APP.

BN-9, a chimeric peptide with mixed opioid and neuropeptide FF receptor agonistic properties, produces nontolerance-forming antinociception in mice.

BACKGROUND AND PURPOSE: Neuropeptide FF (NPFF) behaves as an endogenous opioid-modulating peptide. In the present study, the opioid and NPFF pharmacophore-containing chimeric peptide BN-9 was synthesized and pharmacologically characterized. EXPERIMENTAL APPROACH: Agonist activities of BN-9 at opioid and NPFF receptors were characterized in in vitro cAMP assays. Antinociceptive activities of BN-9 were evaluated in the mouse tail-flick and formalin tests. Furthermore, its side effects were investigated in rotarod, antinociceptive tolerance, reward and gastrointestinal transit tests. KEY RESULTS: BN-9 acted as a novel multifunctional agonist at µ, δ, κ, NPFF1 and NPFF2 receptors in cAMP assays. In the tail-flick test, BN-9 produced dose-related antinociception and was approximately equipotent to morphine; this antinociception was blocked by µ and κ receptor antagonists, but not by the δ receptor antagonist. In the formalin test, supraspinal administration of BN-9 produced significant analgesia. Notably, repeated administration of BN-9 produced analgesia without loss of potency over 8 days. In contrast, repeated i.c.v. co-administration of BN-9 with the NPFF receptor antagonist RF9 produced significant antinociceptive tolerance. Furthermore, i.c.v. BN-9 induced conditioned place preference. When given by the same routes, BN-9 had a more than eightfold higher ED50 value for gastrointestinal transit inhibition compared with the ED50 values for antinociception. CONCLUSIONS AND IMPLICATIONS: BN-9 produced a robust, nontolerance-forming analgesia with limited inhibition of gastrointestinal transit. As BN-9 is able to activate both opioid and NPFF systems, this provides an interesting approach for the development of novel analgesics with minimal side effects.

Effects of tetramethylpyrazine on neuronal apoptosis in the superficial dorsal horn in a rat model of neuropathic pain.

The Bennett and Xie (1988) model of chronic constriction injury (CCI) investigated the effects of tetramethylpyrazine (TMP) on neuropathic pain-associated behaviors and neuronal apoptosis in the spinal dorsal horn. Fifty-four male rats were randomly divided into sham (group S), CCI (group C) and TMP groups (group T). Each group was divided into subgroups (n = 6 in each group) according the time of sacrifice: 3 d, 7 d and 14 d. Rat sciatic nerves were unligated (group S), or the right sciatic nerve was loosely ligated (groups C and T) to produce CCI. Mechanical withdrawal thresholds (MWTs) and thermal withdrawal latencies (TWLs) were measured, and the rats were sacrificed at different time points post-operation. The L4-L6 sections of the spinal cord were removed. Apoptotic changes were evaluated using the TUNEL method. Immunohistochemistry assessed Bcl-2 and caspase-3 expression. TMP treatment increased MWT and TWL values and Bcl-2 expression, but it reduced neuronal apoptosis and caspase-3 expression in laminae I-II of the spinal dorsal horn. These results suggested that the inhibition of neuronal apoptosis via the modulation of Bcl-2 and caspase-3 proteins in the rat spinal dorsal horn contributed to TMP-induced analgesia.

[Clonidine and dexmedetomidine's effect on the altered expressions of growth associated protein-43 mRNA in rat dorsal root ganglion during the development of chronic neuropathic pain].

OBJECTIVE: To explore the effects of α(2) adrenergic receptor (α(2)AR) agonists clonidine and dexmedetomidine on the injury model of peripheral nerve chronic constriction in rats. METHODS: A total of 72 male SD rats weighing 180 - 250 g were randomly divided into 4 groups (n = 18 each). In sham operation group (S), the right sciatic nerves were exposed but not ligated. But, in other groups, four ligatures were placed around the right sciatic nerve according to the Bennett's method. From the instant after operation, 0.4 mg × kg(-1)× d(-1) clonidine and 50.0 µg × kg(-1)× d(-1) were injected intraperitoneally into the clonidine group (CL) and dexmedetomidine group (Dex) daily. And the same volume of normal saline was injected into the S and CCI groups (C) respectively. Mechanical and thermal pain thresholds were measured by paw withdrawal latencies at Day 1 pre-operation and Day 3, 7 and 14 post-operation. After that, the L(4-6) dorsal root ganglions to chronic constriction injured sciatic nerves were harvested. Reverse transcription-polymerase chain reaction (RT-PCR) and agarose gel electrophoresis were used to examine the expression of GAP-43 mRNA. RESULTS: Mechanical withdrawal threshold (MWT) and thermal withdrawal latency (TWL) of groups C, CL and Dex markedly decreased and the expression of GAP-43 mRNA in dorsal root ganglions significantly increased at Days 3, 7 and 14 post-operation versus those at pre-operation and group S (P < 0.05). TWL and MWT of groups CL and Dex at Days 7 and 14 post-operation significantly increased while the expression of GAP-43 mRNA in dorsal root ganglions markedly decreased versus those of group C (P < 0.05). TWL and MWT of group Dex were significantly higher while the expression of GAP-43 mRNA in dorsal root ganglions was lower than those of group CL (P < 0.05). Compared with Day 3, TWL and MWT of groups C, CL and Dex markedly decreased while the expression of GAP-43 mRNA significantly increased in dorsal root ganglions at Day 7 (P < 0.05). Compared with Day 7, TWL and MWT of groups CL and Dex markedly increased while the expression of GAP-43 mRNA in dorsal root ganglions significantly decreased at Day 14 (P < 0.05). CONCLUSION: Clonidine and dexmedetomidine both show evident analgesic effects on chronic neuropathic pain in rats probably through a reduction of nerve regeneration. But dexmedetomidine has a better efficacy due to of its high selectivity of α(2)AR.

[Influence of FPS on the expression of LDL-R mRNA in the liver tissues of hyperlipidemic rats].

OBJECTIVE: To explore the effect of FPS on low-density lipoprotein acceptor (LDL-R) mRNA in the liver tissues of hyperlipidemic rats. METHODS: Sixty healthy male SD rats were randomly divided into six groups: normal control, model control, Gynostemma pentaphyllum, FPS low dosage, FPS moderate dosage, and FPS high dosage group. Excepting the rats in the normal control group, the ones in other groups were all made rats' hyperlipidemic model by irrigating hyperlipidemic emulsion into the stomach and observed the expression of LDL-R mRNA in the liver tissues of rats of each group. RESULTS: Relative content of LDL-RmRNA in low and moderate dosage groups was notably higher than that inmodel group. The contents's difference was not remarkable between FPS moderate dosage group and Gynostemma pentaphyllum group. CONCLUSION: FPS can appreciably increase the expression of LDL-R mRNA in the liver tissues of hyperlipidemic rats and promote the elimination ofLDL-C to reduce serum cholesterol notably.