Metastasis and immunosuppression promoted by mtDNA and PD-L1 in extracellular vesicles are reversed by WGP ß-glucan in oral squamous cell carcinoma.

The suppressive regulatory T cells (Treg) are frequently upregulated in cancer patients. This study aims to demonstrate the hypothesis that arecoline could induce the secretion of mitochondrial (mt) DNA D-loop and programmed cell death-ligand 1 (PD-L1) in extracellular vesicles (EVs), and attenuate T-cell immunity by upregulated Treg cell numbers. However, the immunosuppression could be reversed by whole glucan particle (WGP) ß-glucan in oral squamous cell (OSCC) patients. Arecoline-induced reactive oxygen specimen (ROS) production and cytosolic mtDNA D-loop were analyzed in OSCC cell lines. mtDNA D-loop, PD-L1, IFN-γ, and Treg cells were also identified for the surgical specimens and sera of 60 OSCC patients. We demonstrated that higher mtDNA D-loop, PD-L1, and Treg cell numbers were significantly correlated with larger tumor size, nodal metastasis, advanced clinical stage, and areca quid chewing. Furthermore, multivariate analysis confirmed that higher mtDNA D-loop levels and Treg cell numbers were unfavorable independent factors for survival. Arecoline significantly induced cytosolic mtDNA D-loop leakage and PD-L1 expression, which were packaged by EVs to promote immunosuppressive Treg cell numbers. However, WGP ß-glucan could elevate CD4+ and CD8+ T-cell numbers, mitigate Treg cell numbers, and promote oral cancer cell apoptosis. To sum up, arecoline induces EV production carrying mtDNA D-loop and PD-L1, and in turn elicits immune suppression. However, WGP ß-glucan potentially enhances dual effects on T-cell immunity and cell apoptosis and we highly recommend its integration with targeted and immune therapies against OSCC.

A systematic scoping review of reflective writing in medical education.

BACKGROUND: Reflective writing (RW) allows physicians to step back, review their thoughts, goals and actions and recognise how their perspectives, motives and emotions impact their conduct. RW also helps physicians consolidate their learning and boosts their professional and personal development. In the absence of a consistent approach and amidst growing threats to RW's place in medical training, a review of theories of RW in medical education and a review to map regnant practices, programs and assessment methods are proposed. METHODS: A Systematic Evidence-Based Approach guided Systematic Scoping Review (SSR in SEBA) was adopted to guide and structure the two concurrent reviews. Independent searches were carried out on publications featured between 1st January 2000 and 30th June 2022 in PubMed, Embase, PsychINFO, CINAHL, ERIC, ASSIA, Scopus, Google Scholar, OpenGrey, GreyLit and ProQuest. The Split Approach saw the included articles analysed separately using thematic and content analysis. Like pieces of a jigsaw puzzle, the Jigsaw Perspective combined the themes and categories identified from both reviews. The Funnelling Process saw the themes/categories created compared with the tabulated summaries. The final domains which emerged structured the discussion that followed. RESULTS: A total of 33,076 abstracts were reviewed, 1826 full-text articles were appraised and 199 articles were included and analysed. The domains identified were theories and models, current methods, benefits and shortcomings, and recommendations. CONCLUSIONS: This SSR in SEBA suggests that a structured approach to RW shapes the physician's belief system, guides their practice and nurtures their professional identity formation. In advancing a theoretical concept of RW, this SSR in SEBA proffers new insight into the process of RW, and the need for longitudinal, personalised feedback and support.

Acidosis promotes the metastatic colonization of lung cancer via remodeling of the extracellular matrix and vasculogenic mimicry.

Acidosis is a hallmark of the tumor microenvironment caused by the metabolic switch from glucose oxidative phosphorylation to glycolysis. It has been associated with tumor growth and progression; however, the precise mechanism governing how acidosis promotes metastatic dissemination has yet to be elucidated. In the present study, a long­term acidosis model was established using patient­derived lung cancer cells, to identify critical components of metastatic colonization via transcriptome profiling combined with both in vitro and in vivo functional assays, and association analysis using clinical samples. Xenograft inoculates of 1 or 10 acidotic cells mimicking circulating tumor cell clusters were shown to exhibit increased tumor incidence compared with their physiological pH counterparts. Transcriptomics revealed that profound remodeling of the extracellular matrix (ECM) occurred in the acidotic cells, including upregulation of the integrin subunit α­4 (ITGA4) gene. In clinical lung cancer, ITGA4 expression was found to be upregulated in primary tumors with metastatic capability, and this trait was retained in the corresponding secondary tumors. Expression of ITGA4 was markedly upregulated around the vasculogenic mimicry structures of the acidotic tumors, while acidotic cells exhibited a higher ability of vasculogenic mimicry in vitro. Acidosis was also found to induce the enrichment of side population cells, suggesting an enhanced resistance to noxious attacks of the tumor microenvironment. Taken together, these results demonstrated that acidosis actively contributed to tumor metastatic colonization, and novel mechanistic insights into the therapeutic management and prognosis of lung cancer were discussed.

Differences in Subjective Memory Impairment, Depressive Symptoms, Sleep, and Physical Activity in African American and Asian American Elderly.

Background: Subjective memory impairment (SMI) is associated with negative health outcomes including mild cognitive impairment and Alzheimer's disease. However, ethnic differences in SMI and disparities in risk factors associated with SMI among minority populations are understudied. The study examined the ethnic differences in SMI, whether SMI was associated with depressive symptoms, sleep, and physical activity (PA), and whether the associations vary across racial/ethnic groups. Methods: Participants included 243 African and Asian Americans (including Chinese, Vietnamese, and Korean Americans) aged 50 or older. Demographic information, SMI, depressive symptoms, daily sleeping hours, and PA levels were assessed. Results: Vietnamese Americans reported the highest SMI score. Depressive symptoms, sleeping hours, and PA levels were significantly associated with SMI. Depressive symptoms were the only significant factor across all ethnic groups. Significant interaction effects were found between ethnicity and health behaviors in predicting SMI. In particular, Vietnamese American participants with greater depressive symptoms and physical inactivity were significantly more likely to experience SMI compared to other ethnic groups Conclusions: Our findings demonstrate ethnic differences in SMI and its association with depressive symptoms, sleep, and PA, which highlight the importance of considering the unique cultural and historical backgrounds across different racial/ethnic groups when examining cognitive functioning in elderly.

Healing kinetics of diabetic wounds controlled with charge-biased hydrogel dressings.

The present study investigates the properties and use as wound-dressing materials of hydrogels made of negatively charged 3-sulfopropyl methacrylate (SA) and positively charged [2-(methacryloyloxy)ethyl]trimethylammonium (TMA) to form poly(SA-co-TMA) gels with/without a charge bias. Their actual chemical compositions were ascertained by XPS which revealed a fair control of the final gel composition obtained from the initial molar ratio in the reaction solution. Zeta potential measurements confirmed the controlled charge bias on which swelling ratio was found to strongly depend, i.e., positively charged or negatively charged gels have a higher tendency to swell than poly(SA-co-TMA) made of 50 mol% of each unit. The anti-biofouling properties were also correlated to the charge bias, i.e., negatively charged and neutral gels resisted well to biofouling by fibrinogen and whole blood, and were much less cytotoxic than their positive counterparts. Applied as wound-dressing materials onto diabetic wounds, it was found that wound closure was almost reached after 21 days, regardless of the gel composition. However, histological analysis revealed that positively charged gels accelerated hemostasis, while neutral gels, much less cytotoxic, were more efficient in the following stages during which the granulation layer and dermis were fully remodelled leading to a dense fibroblast population and thick collagen with no sign of inflammation. All in all, this study sheds light on the effects of charge bias on different wound healing stages and proves the efficiency of pseudo-zwitterionic poly(SA-co-TMA) to heal diabetic wounds for the first time.

Comparison of annual and biannual mass antibiotic administration for elimination of infectious trachoma.

CONTEXT: Treatment recommendations assume that repeated mass antibiotic distributions can control, but not eradicate or even locally eliminate, the ocular strains of chlamydia that cause trachoma. Elimination may be an important end point because of concern that infection will return to communities that have lost immunity to chlamydia after antibiotics are discontinued. OBJECTIVE: To determine whether biannual treatment can eliminate ocular chlamydial infection from preschool children and to compare results with the World Health Organization-recommended annual treatment. DESIGN, SETTING, AND PARTICIPANTS: A cluster-randomized clinical trial of biannual vs annual mass azithromycin administrations to all residents of 16 rural villages in the Gurage Zone, Ethiopia, from March 2003 to April 2005. INTERVENTIONS: At scheduled treatments, all individuals aged 1 year or older were offered a single dose of oral azithromycin either annually or biannually. MAIN OUTCOME MEASURE: Village prevalence of ocular chlamydial infection and presence of elimination at 24 months in preschool children determined by polymerase chain reaction, correcting for baseline prevalence. Antibiotic treatments were performed after sample collections. RESULTS: Overall, 14,897 of 16,403 eligible individuals (90.8%) received their scheduled treatment. In the villages in which residents were treated annually, the prevalence of infection in preschool children was reduced from a mean of 42.6% (range, 14.7%-56.4%) to 6.8% (range, 0.0%-22.0%) at 24 months. In the villages in which residents were treated biannually, infection was reduced from 31.6% pretreatment (range, 6.1%-48.6%) to 0.9% (range, 0.0%-4.8%) at 24 months. Biannual treatment was associated with a lower prevalence at 24 months (P = .03, adjusting for baseline prevalence). At 24 months, no infection could be identified in 6 of 8 of those treated biannually and in 1 of 8 of those treated annually (P = .049, adjusting for baseline prevalence). CONCLUSION: Local elimination of ocular chlamydial infection appears feasible even in the most severely affected areas, although it may require biannual mass antibiotic distributions at a high coverage level. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00221364.

Chlamydia on children and flies after mass antibiotic treatment for trachoma.

There are various approaches to control trachoma. These include the elimination of the ocular strains of Chlamydia trachomatis that cause the disease and to decrease the spread of infection by other measures such as fly control. Here, we examined how these two are related (i.e., how treating children with antibiotics affects carriage of Chlamydia by flies). Flies were collected in villages that had received mass oral azithromycin distribution and were compared with flies in untreated villages. Polymerase chain reaction (PCR) was performed to detect chlamydial DNA on the flies. Conjunctival swabs were also taken to assay for chlamydial prevalence in the children. Chlamydia was found on 23% of the flies in the untreated villages but only 0.3% in treated villages. Prevalence of trachoma in children proved to be an excellent predictor of the prevalence on flies (correlation coefficient, 0.89). Thus, treating children with antibiotics may drastically reduce the role of flies as a vector.

A rationale for continuing mass antibiotic distributions for trachoma.

BACKGROUND: The World Health Organization recommends periodic mass antibiotic distributions to reduce the ocular strains of chlamydia that cause trachoma, the world's leading cause of infectious blindness. Their stated goal is to control infection, not to completely eliminate it. A single mass distribution can dramatically reduce the prevalence of infection. However, if infection is not eliminated in every individual in the community, it may gradually return back into the community, so often repeated treatments are necessary. Since public health groups are reluctant to distribute antibiotics indefinitely, we are still in need of a proven long-term rationale. Here we use mathematical models to demonstrate that repeated antibiotic distributions can eliminate infection in a reasonable time period. METHODS: We fit parameters of a stochastic epidemiological transmission model to data collected before and 6 months after a mass antibiotic distribution in a region of Ethiopia that is one of the most severely affected areas in the world. We validate the model by comparing our predicted results to Ethiopian data which was collected biannually for two years past the initial mass antibiotic distribution. We use the model to simulate the effect of different treatment programs in terms of local elimination of infection. RESULTS: Simulations show that the average prevalence of infection across all villages progressively decreases after each treatment, as long as the frequency and coverage of antibiotics are high enough. Infection can be eliminated in more villages with each round of treatment. However, in the communities where infection is not eliminated, it returns to the same average level, forming the same stationary distribution. This phenomenon is also seen in subsequent epidemiological data from Ethiopia. Simulations suggest that a biannual treatment plan implemented for 5 years will lead to elimination in 95% of all villages. CONCLUSION: Local elimination from a community is theoretically possible, even in the most severely infected communities. However, elimination from larger areas may require repeated biannual treatments and prevention of re-introduction from outside to treated areas.

Topical flurbiprofen toxicosis in a cat.

OBJECTIVE: To describe the clinical presentation and treatment of a cat with flurbiprofen toxicosis due to topical cream exposure. CASE SUMMARY: A 3-year-old castrated male domestic shorthair cat presented to an emergency and referral center for acute lethargy, hematemesis, and anemia. Severe azotemia was observed on serum biochemistry panel. The patient's anemia was treated with packed RBC transfusion, and treatment with crystalloid fluids, famotidine, pantoprazole, ampicillin, and sucralfate were begun on presentation. Anemia became intractable and the patient received multiple packed RBC and whole blood transfusions. Severe gastric ulcerations and duodenal perforation were confirmed via gastroduodenoscopy, and the patient was treated with surgical excision and repair of duodenal perforation. Azotemia resolved with IV fluid therapy, and anemia resolved following surgery. The patient recovered and was discharged after 9 days of hospitalization. The patient had likely been exposed to the owner's compounded pain relief cream containing 10% flurbiprofen. There was confirmation of flurbiprofen exposure via acid extraction urine analysis at a university toxicology laboratory. NEW OR UNIQUE INFORMATION PROVIDED: This is the first described case of flurbiprofen toxicosis due to topical cream exposure in a cat.

Effect of a single mass antibiotic distribution on the prevalence of infectious trachoma.

CONTEXT: The World Health Organization recommends mass antibiotic distributions in its strategy to eliminate blinding trachoma as a public health concern. Some hypothesize that a single distribution is sufficient to control the ocular strains of chlamydia that cause trachoma. Others believe infection will inevitably return and periodic treatments or other measures are essential. OBJECTIVE: To determine whether ocular chlamydial infection returns to the community up to 24 months after a single mass antibiotic distribution in a hyperendemic region of Ethiopia. DESIGN, SETTING, AND PARTICIPANTS: Longitudinal cohort study conducted March 2003 to March 2005 in the Gurage Zone of Ethiopia. Eight randomly selected villages were assessed for ocular chlamydial infection. Fifteen untreated villages were randomly chosen at 12 months to allow assessment of a secular trend. INTERVENTION: A single dose of oral azithromycin was offered to all residents of the 8 selected villages who were aged 1 year or older. MAIN OUTCOME MEASURE: Prevalence of ocular chlamydial infection in all children aged 1 to 5 years from each intervention village prior to treatment and 2, 6, 12, 18, and 24 months after mass antibiotic treatment, and also in untreated villages enrolled at 12 months. RESULTS: Five hundred fifteen children were examined for ocular chlamydial infection at baseline. For the follow-up examinations, the mean participation rate was 83%. The mean prevalence of infection in children aged 1 to 5 years decreased from 43.5% (95% confidence interval [CI], 35.0%-52.0%) to 5.1% (95% CI, 1.1%-9.2%) after treatment. On average, infection returned gradually over 24 months to 11.3% (95% CI, 4.5%-18.1%; P = .001). In 7 of 8 villages, infection was higher at 24 months than at 2 months. In the remaining village, no infection could be identified at any point after treatment. Villages enrolled at 12 months had significantly fewer infections than those enrolled 12 months earlier, suggesting a secular trend (P<.001). CONCLUSIONS: Ocular chlamydial infection was not eliminated in children aged 1 to 5 years after a single mass azithromycin distribution; it slowly returned over 24 months, although not to baseline levels. Repeated treatments or other effective measures will be necessary for elimination.

Preclinical Efficacy and Safety Profile of Allometrically Scaled Doses of Doxycycline Used to Turn "On" Therapeutic Transgene Expression from High-Capacity Adenoviral Vectors in a Glioma Model.

Glioblastoma multiforme (GBM) is the most commonly occurring primary brain cancer in adults, in whom its highly infiltrative cells prevent total surgical resection, often leading to tumor recurrence and patient death. Our group has discovered a gene therapy approach for GBM that utilizes high-capacity "gutless" adenoviral vectors encoding regulatable therapeutic transgenes. The herpes simplex type 1-thymidine kinase (TK) actively kills dividing tumor cells in the brain when in the presence of the prodrug, ganciclovir (GCV), whereas the FMS-like tyrosine kinase 3 ligand (Flt3L) is an immune-stimulatory molecule under tight regulation by a tetracycline-inducible "Tet-On" activation system that induces anti-GBM immunity. As a prelude to a phase I clinical trial, we evaluated the safety and efficacy of Food and Drug Administration (FDA)-approved doses of the tetracycline doxycycline (DOX) allometrically scaled for rats. DOX initiates the expression of Flt3L, which has been shown to recruit dendritic cells to the brain tumor microenvironment-an integral first step in the development of antitumor immunity. The data revealed a highly safe profile surrounding these human-equivalent doses of DOX under an identical therapeutic window as proposed in the clinical trial. This was confirmed through a neuropathological analysis, liver and kidney histopathology, detection of neutralizing antibodies, and systemic toxicities in the blood. Interestingly, we observed a significant survival advantage in rats with GBM receiving the 300 mg/day equivalent dosage of DOX versus the 200 mg/day equivalent. Additionally, rats rejected "recurrent" brain tumor threats implanted 90 days after their primary brain tumors. We also show that DOX detection within the plasma can be an indicator of optimal dosing of DOX to attain therapeutic levels. This work has significant clinical relevance for an ongoing phase I clinical trial in humans with primary GBM and for other therapeutic approaches using Tet-On transactivation system in humans.

Methionine aminopeptidases and angiogenesis.

The initiator methionine residue of proteins is removed during synthesis by a specific and ubiquitous enzyme, methionine aminopeptidase (MetAP). Prokaryotes have a single gene, while eukaryotes have two isoforms. This family of metalloenzymes generally cleaves substrates in which the penultimate residue is one of the seven smaller amino acids (glycine, alanine, serine, threonine, proline, cysteine and valine). One of the eukaryotic isoforms (MetAP2) has an additional non-proteolytic function and is the principle target of a family of anti-angiogenic drugs that are related to fumagillin. The resulting covalent modification inhibits the protease activity of MetAP2 and blocks cell-cycle function in endothelial and some cancer cells. The role of MetAP2 in the mitogenic activity of these cells is unknown.

Disappearance of trachoma from Western Nepal.

We assessed how much of the observed decline in the prevalence of trachoma in a district of Western Nepal was due to an antibiotic treatment program and how much to an underlying secular trend outside of the program. Although antibiotic treatments clearly have an effect at 6 months, we were unable to show that this effect persisted at 12 months; in fact, long-term gains may be due to a secular trend in the area.

Mass antibiotic treatment and community protection in trachoma control programs.

Azithromycin is highly effective against trachoma, but the practical difficulties of community-wide distribution often leave many individuals untreated. We demonstrate, after mass azithromycin treatment of a population in Ethiopia, an indirect protective effect that occurred among untreated children who resided in villages in which most individuals had been treated. Similarities with the indirect protection within a treated community (i.e., "herd protection") that has been observed in vaccination programs are discussed.

How reliable is the clinical exam in detecting ocular chlamydial infection?

PURPOSE: To describe the relationship between the clinical exam for trachoma and the polymerase chain reaction (PCR) for ocular chlamydia. METHODS: One hundred children in a trachoma-endemic area of Ethiopia were examined three times and swabbed twice for PCR analysis. The assays were compared, and an analysis of the variance between exam and PCR was performed. RESULTS: Inter-examiner agreement was 0.57 (Cohen's kappa), inter-PCR agreement 0.98, and agreement between examiner and PCR, 0.26-0.34. The positive predictive value of the exam in identifying infection was 66%. Inter-examiner variance accounted for 30% of the total variance between the exam and PCR, with the remainder presumably due to an underlying difference in what the exam and PCR measure. CONCLUSIONS: Despite modest inter-grader reliability and correlation with evidence of infection, the clinical exam is widely used due to its convenience and low cost. Efforts to make laboratory tests for ocular Chlamydia trachomatis more affordable would be useful.

Feasibility of eliminating ocular Chlamydia trachomatis with repeat mass antibiotic treatments.

CONTEXT: Mass antibiotic administrations for ocular chlamydial infection play a key role in the World Health Organization's trachoma control program. Mathematical models suggest that it is possible to eliminate trachoma locally with repeat mass treatment, depending on the coverage level of the population, frequency of mass treatments, and rate that infection returns into a community after each mass treatment. Precise estimates of this latter parameter have never been reported. OBJECTIVE: To determine the rate at which chlamydial infection returns to a population after mass treatment and to estimate the treatment frequency required for elimination of ocular chlamydia from a community. DESIGN, SETTING, AND PARTICIPANTS: Longitudinal cohort study of 24 randomly selected villages from the Gurage Zone in Ethiopia conducted February 2003 to October 2003. A total of 1332 children aged 1 to 5 years were monitored for prevalence of ocular chlamydial infection pretreatment and 2 and 6 months posttreatment. INTERVENTIONS: All individuals older than 1 year were eligible for single-dose oral azithromycin treatment. Pregnant women were offered tetracycline eye ointment. MAIN OUTCOME MEASURES: Prevalence of ocular chlamydial infection, measured by polymerase chain reaction, in children aged 1 to 5 years, in each of 24 villages at each time point was used to estimate the rate of return of infection and the treatment frequency necessary for elimination. RESULTS: The prevalence of infection was 56.3% pretreatment (95% confidence interval [CI], 47.5%-65.1%), 6.7% 2 months posttreatment (95% CI, 4.2%-9.2%), and 11.0% 6 months posttreatment (95% CI, 7.3%-14.7%). Infection returned after treatment at an exponential rate of 12.3% per month (95% CI, 4.6%-19.9% per month). The minimum treatment frequency necessary for elimination was calculated to be once every 11.6 months (95% CI, 7.2-30.9 months), given a coverage level of 80%. Thus, biannual treatment, already being performed in some areas, was estimated to be more than frequent enough to eventually eliminate infection. CONCLUSION: The rate at which ocular chlamydial infection returns to a community after mass treatment suggests that elimination of infection in a hyperendemic area is feasible with biannual mass antibiotic administrations and attainable coverage levels.

Cancer-associated fibroblasts regulate the plasticity of lung cancer stemness via paracrine signalling.

Cancer stem cells (CSCs) are a promising target for treating cancer, yet how CSC plasticity is maintained in vivo is unclear and is difficult to study in vitro. Here we establish a sustainable primary culture of Oct3/4(+)/Nanog(+) lung CSCs fed with CD90(+) cancer-associated fibroblasts (CAFs) to further advance our knowledge of preserving stem cells in the tumour microenvironment. Using transcriptomics we identify the paracrine network by which CAFs enrich CSCs through de-differentiation and reacquisition of stem cell-like properties. Specifically, we find that IGF1R signalling activation in cancer cells in the presence of CAFs expressing IGF-II can induce Nanog expression and promote stemness. Moreover, this paracrine signalling predicts overall and relapse-free survival in stage I non-small cell lung cancer (NSCLC) patients. IGF-II/IGF1R signalling blockade inhibits Nanog expression and attenuates cancer stem cell features. Our data demonstrate that CAFs constitute a supporting niche for cancer stemness, and targeting this paracrine signalling may present a new therapeutic strategy for NSCLC.

Association of conjunctival bacterial infection and female sex in cicatricial trachoma.

PURPOSE: Conjunctival infection with non-chlamydial bacteria may play an important role in the progression of trachoma, especially with regard to the development of corneal opacity and blindness. To further characterize the microbiological profile of bacterial conjunctival infections in cicatricial trachoma, a conjunctival swabbing of adults in rural Ethiopia was performed. METHODS: In a cross-sectional study conducted in nine Ethiopian villages with hyperendemic trachoma, persons 40 years of age or older with signs or symptoms consistent with trichiasis were recruited and conjunctival swabbing for bacterial pathogens was performed. RESULTS: Conjunctival examination and swabbing on 112 females and 36 males were performed. Of the 148 study participants, 101 (68.2%) were confirmed to have trichiasis, and 118 (80%) had conjunctival swabs positive for bacteria. In multivariate analyses, growth of pathogenic conjunctival bacteria was independently associated with trichiasis (odds ratio [OR] 6.93; 95% confidence interval [CI] 2.71-17.7) and female sex (OR 5.90; 95% CI 2.09-16.7). Females were more likely to have swabs positive for Streptococcus pneumoniae or Haemophilus influenzae than were males (OR 9.09; 95% CI 1.17-70.8). CONCLUSIONS: In a region of Ethiopia with endemic trachoma, conjunctival bacterial growth was more common in females than that in males. S. pneumoniae and H. influenzae, both of which frequently colonize the nasopharynx of children, were more common in females, suggesting that the preponderance of infection in females may be attributable to close contact with children. This finding is consistent with the theory that childcare activities may preferentially expose females to ocular chlamydial infection. (ClinicalTrials.gov number, NCT00221364.).

Assessing cervical dislocation as a humane euthanasia method in mice.

Research investigators often choose to euthanize mice by cervical dislocation (CD) when other methods would interfere with the aims of a research project. Others choose CD to assure death in mice treated with injected or inhaled euthanasia agents. CD was first approved for mouse euthanasia in 1972 by the AVMA Panel on Euthanasia, although scientific assessment of its humaneness has been sparse. Here we compared 4 methods of spinal dislocation--3 targeting the cervical area (CD) and one the thoracic region--in regard to time to respiratory arrest in anesthetized mice. Of the 81 mice that underwent CD by 1 of the 3 methods tested, 17 (21%) continued to breathe, and euthanasia was scored as unsuccessful. Postmortem radiography revealed cervical spinal lesions in 5 of the 17 cases of unsuccessful CD euthanasia. In addition, 63 of the 64 successfully euthanized mice had radiographically visible lesions in the high cervical or atlantooccipital region. In addition, 50 of 64 (78%) mice euthanized successfully had radiographically visible thoracic or lumbar lesions or both. Intentionally creating a midthoracic dislocation in anesthetized mice failed to induce respiratory arrest and death in any of the 18 mice subjected to that procedure. We conclude that CD of mice holds the potential for unsuccessful euthanasia, that anesthesia could be valuable for CD skills training and assessment, and that postmortem radiography has minimal promise in quality-control assessments.

Clinical activity and polymerase chain reaction evidence of chlamydial infection after repeated mass antibiotic treatments for trachoma.

It is unclear how the prevalence of clinically active trachoma correlates with the prevalence of ocular chlamydial infection at the community level. In 24 villages from a cluster-randomized clinical trial of mass azithromycin distributions in Ethiopia, the correlation between the prevalence of clinical activity (on examination) and chlamydial infection (by polymerase chain reaction) was moderately strong before mass antibiotic treatments (Pearson's correlation coefficient r = 0.75, 95% confidence interval [CI] = 0.52-0.87), but decreased at each time point during four biannual treatments (at 24 months, r = 0.15, 95% CI = -0.14-0.41). One year after the final treatment, the correlation coefficient had increased, but not to the pre-treatment level (r = 0.55, 95% CI = 0.30-0.73). In a region with hyperendemic trachoma, conjunctival examination was a useful indicator of the prevalence of chlamydial infection before treatments, less useful during mass treatments, but regained utility by one year after treatments had stopped.