Frequency and characterization of the accessory heads of the biceps brachii: A multicentric cadaveric study.

PURPOSE: The biceps brachii muscle (BBM) is a large and thick muscle on the ventral portion of the upper arm. The scientific literature reports the existence of extra heads. OBJECTIVE: The present work investigated the frequency of occurrence of BBM accessory head(s) in four different Anatomy Laboratories at universities in Northeast Brazil. MATERIAL AND METHODS: Once the upper limbs with an anatomical variation of the BBM heads were identified, the accessory head was evaluated for morphometric characterization (the length, width, and thickness). RESULTS: The sample consisted of 249 upper limbs and the outcomes were 26 members with BBM accessory heads (10.44% of the total sample). Among the 26 members studied was found a single accessory head in 22 (84.62%), two accessory heads in 3 (11.54%), and three accessory heads in 1 (3.85%). BBMs with one, two, and three accessory heads were found, with different origins. The average length, width, and thickness of these accessory heads were 169.39mm, 10.25mm, and 3.39mm, respectively. CONCLUSION: The frequency of BBM accessory heads in a population of northeastern Brazil in this cadaveric study was 10.44%.

Excess mortality associated with COVID-19 in Brazil: 2020-2021.

OBJECTIVE: To evaluate excess mortality in Brazil from January 2020 to April 2021, according to the primary causes of death registered in the Brazilian Mortality Information System (MIS). METHODS: Cross-sectional study with data extracted from the MIS. Excess deaths were examined by the primary cause of death according to 11 grouped causes. Autoregressive models used mortality data from 2015 to 2019 to predict expected deaths from January 2020 to April 2021. Excess deaths were calculated as the difference between the observed and the expected number of deaths. RESULTS: Total excess deaths of 370 055 were observed in the studied period, corresponding to a ratio of observed to expected of 1.14 in 2020 and 1.40 in 2021. Excess deaths were seen in three groups: symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified; other diseases of the respiratory system and coronavirus infection, unspecified site. CONCLUSIONS: The excess mortality in Brazil in these 16 months was 1.20 times greater than the previous year. The increase in not elsewhere classified causes and causes of death associated to COVID-19 indicate caution about the negative balance for some causes. Furthermore, the inequalities of mortality reporting systems in low- and middle-income countries in relation to underestimation of mortality still need to be addressed.

Efficacy of hydrogen peroxide wipes for decontamination of AZD1222 adenovirus COVID-19 vaccine strain on pharmaceutical industry materials.

This study aimed to evaluate the performance of accelerated hydrogen peroxide® wipes (HPW) for decontamination of the chimpanzee adenovirus AZD1222 vaccine strain used in the production of recombinant COVID-19 vaccine in a pharmaceutical industry. Two matrices were tested on stainless-steel (SS) and low-density-polyethylene (LDP) surfaces: formulated recombinant COVID-19 vaccine (FCV) and active pharmaceutical ingredient (API). The samples were spiked, dried and the initial inoculum, possible residue effect (RE) and titre reduction after disinfection with HPW were determined. No RE was observed. The disinfection procedure with HPW resulted in complete decontamination the of AZD1222 adenovirus strain in FCV (≥7·46 and ≥7·49 log10 infectious unit [IFU] ml-1 for SS and LDP carriers respectively) and API (≥8·79 and ≥8·78 log10 IFU ml-1 for SS and LDP carriers respectively). In conclusion, virucidal activity of HPW was satisfactory against the AZD1222 adenovirus strain and can be a good option for disinfection processes of SS and LPD surfaces in pharmaceutical industry facilities during recombinant COVID-19 vaccine production. This procedure is simple and can be also applied on safety unit cabins and sampling bags made of LDP as well.

Evaluation of hydrogen peroxide efficacy against AZD1222 chimpanzee adenovirus strain in the recombinant COVID-19 vaccine for application in cleaning validation in a pharmaceutical manufacturing industry.

This study aimed to evaluate the performance of hydrogen peroxide vapour (HPV) to inactivate the chimpanzee adenovirus AZD1222 vaccine strain used in the production of recombinant COVID-19 vaccine for application in cleaning validation in pharmaceutical industries production areas. Two matrixes were tested: formulated recombinant COVID-19 vaccine (FCV) and active pharmaceutical ingredient (API). The samples were dried on stainless steel and exposed to HPV in an isolator. One biological indicator with population >106 Geobacillus stearothermophilus spores was used to validate the HPV decontamination cycle as standard. HPV exposure resulted in complete virus inactivation in FVC (≥5·03 log10 ) and API (≥6·40 log10 ), showing HPV efficacy for reducing chimpanzee adenovirus AZD1222 vaccine strain. However, the optimum concentration and contact time will vary depending on the type of application. Future decontamination studies scaling up the process to the recombinant COVID-19 vaccine manufacturing areas are necessary to evaluate if the HPV will have the same or better virucidal effectivity in each specific production area. In conclusion, HPV showed efficacy for reducing AZD1222 chimpanzee adenovirus strain and can be a good choice for pharmaceutical industries facilities disinfection during recombinant COVID-19 vaccine production.

Two novel pathogenic variants in MED13L: one familial and one isolated case.

BACKGROUND: Genetic variants involving the MED13L gene can lead to an autosomal dominant syndrome characterised by intellectual disability/developmental delay and facial dysmorphism. METHODS: We investigated two cases (one familial and one isolated) of intellectual disability with speech delay and dysmorphic facial features by whole-exome sequencing analyses. Further, we performed a literature review about clinical and molecular aspects of MED13L gene and syndrome. RESULTS: Two MED13L variants have been identified [MED13L(NM_015335.5):c.4417C>T and MED13L(NM_015335.5):c.2318delC] and were classified as pathogenic according to the ACMG (American College of Medical Genetics and Genomics) guidelines. One of the variants was present in sibs. CONCLUSIONS: The two pathogenic variants identified have not been previously reported. Importantly, this is the first report of a familial case of MED13L nonsense mutation. Although the parents of the affected children were no longer available for analysis, their apparently normal phenotypes were surmised from familial verbal descriptions corresponding to normal mental behaviour and phenotype. In this situation, the familial component of mutation transmission might be caused by gonadal mosaicism of a MED13L mutation in a gonad from either the father or the mother. The case reports and the literature review presented in this manuscript can be useful for genetic counselling.

Coverage and factors associated with receiving campaign polio vaccines in an urban population in Guinea-Bissau.

BACKGROUND: Polio eradication campaigns are intended to complement routine immunization. Studies addressing factors associated with campaign coverage are warranted to identify children missed by campaigns. METHODS: Bandim Health Project runs demographic surveillance with registration of routine immunization and campaign participation data in urban Guinea-Bissau. We assessed coverage and factors associated with receiving campaign polio vaccines in children aged 0-35 months in two polio eradication campaigns conducted in 2017 and 2018 using univariate and multivariate regression models. RESULTS: Campaign coverage reached 84% in 2017 and 88% in 2018. We found lower coverage among children of young and not formally educated mothers in univariate analyses; Children <9 months and Fula children had lower campaign coverage in both univariate and multivariate analyses. CONCLUSIONS: To increase campaign coverage in urban Guinea-Bissau attention may be directed at informing young mothers, mothers of young children, mothers without formal education, and the Fula ethnic group about campaigns.

Association between screen time and accelerometer-measured 24-h movement behaviors in a sample of Brazilian adolescents.

OBJECTIVES: Different screen time activities may be related to sleep, physical activity, and sedentary behavior. The objective was to examine the association between self-reported screen time activities and accelerometer-measured 24-h movement behaviors. STUDY DESIGN: This was a cross-sectional study. METHODS: Adolescents' (n = 718, 50.4% girls, 16 years) sleep duration, sedentary behavior, light-intensity physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) were estimated with wrist-worn accelerometry. Time spent on screen time activities related to studying, working, watching videos, playing video games, and using social media was self-reported. Multilevel linear regressions were used to test the association between screen time with sleep, sedentary behavior, and physical activity. RESULTS: Boys and girls slept 6.4 and 6.7 h per night, spent 10.4 and 10.1 h/d in sedentary behavior, spent 4.0 and 4.4 h/d in LPA, and spent 34.7 and 29.2 min/d in MVPA, respectively. Studying was inversely related to LPA and MVPA. Working was inversely related to sleep and positively related to LPA. Watching videos was associated with lower LPA and MVPA. For boys, videogames were associated with increased sedentary behavior and lower LPA and MVPA. For girls, studying and/or using social media were associated with lower LPA and MVPA. CONCLUSIONS: Indicators of screen time were associated with different accelerometer-measured 24-h movement behaviors in this sample of Brazilian adolescents.

Factors Associated with Frailty Syndrome in Older Adults.

OBJECTIVE: Frailty is a common geriatric syndrome, characterized by a decrease in energy reserve and stress resistance, resulting in an accumulated decline of multiple physiological systems and greater vulnerability. Frailty syndrome has a multifactorial etiology involving a biological basis associated with sociobehavioral factors. We verify the association of frailty syndrome with family functionality level, nutritional status and medication adherence in older adults. DESIGN: Observational and analytical study. SETTING AND PARTICIPANTS: Conducted at ambulatory the university hospital, with patients aged 60 years or older. MEASUREMENTS: Cognitive function was measured using the Mini-Mental State Examination (MMSE); nutritional status was evaluated using the Mini Nutritional Assessment (MNA) and Body Mass Index, BMI; the 5-item FRAIL scale was used for frailty screening; family functioning was assessed using the Family APGAR Index, which evaluates Adaptability, Partnership, Growth, Affection, and Resolve; Self-reported medication adherence was measured by the eight-item Morisky Medication Adherence Scale (MMAS-8). RESULTS: The study involved 308 older adults, with a mean age of 70.40 years, There was an association between frailty and highly dysfunctional family with an OR of 5.9 (95% CI 1.9-18.5)(p<0.05), nutritional risk assessed by BMI, where low weight presented an OR of 2.5 (95% CI 1.1-5.8) and obesity an OR of 2.8 (95% CI 1.1-7.0)(P <0.05) and a nutritional risk assessed by MNA with an OR 6.3(95% CI 1.9-20.4) and low medication adherence with an OR of 8.9 (95% CI, 3.6-21.6)(P = 0.01). CONCLUSION: Frailty syndrome is associated with high levels of family dysfunction, nutritional risk and poor medication adherence amongst older people.

Sound exposure and its beneficial effects on embryonic growth and hatching of broiler chicks.

1. The physical factors that involve artificial incubation determine embryonic growth and hatching of broiler chicks, and have important implications for the poultry production chain and chick welfare. This study explored the effects of sound exposure on incubation responses (hatching, embryonic development and chick quality).2. A 2 × 2 factorial experiment with the factors 'sound pressure level' (at 70 and 90 dB) and 'species-specific vocalisations' (at 75dB - 85dB) was performed in four experimental incubators (loaded with 90 eggs each) for eight consecutive cycles of incubation, totalling 2880 Cobb-500® broiler breeder eggs.3. Embryonic growth was not influenced by any experimental factor, but the highest sound pressure level (90 dB) led to earlier hatching, higher hatchability, better chick quality and lower weight at hatching. Additional effects of species-specific vocalisations were found at 70 dB noise, which caused early hatching and better chick quality.4. It was concluded that the loud noise found in commercial hatcheries (at 90 dB) can be beneficial. Furthermore, the presence of species-specific vocalisations could improve the hatching time and chick quality from experimental incubators (at 70 dB). However, this would not provide additional benefits in commercial hatcheries, due to the machinery noise masking them.

Strong magnetic exchange and frustrated ferrimagnetic order in a weberite-type inorganic-organic hybrid fluoride.

We combine powder neutron diffraction, magnetometry and 57Fe Mössbauer spectrometry to determine the nuclear and magnetic structures of a strongly interacting weberite-type inorganic-organic hybrid fluoride, Fe2F5(H taz). In this structure, Fe2+ and Fe3+ cations form magnetically frustrated hexagonal tungsten bronze layers of corner-sharing octahedra. Our powder neutron diffraction data reveal that, unlike its purely inorganic fluoride weberite counterparts which adopt a centrosymmetric Imma structure, the room-temperature nuclear structure of Fe2F5(H taz) is best described by a non-centrosymmetric Ima2 model with refined lattice parameters a = 9.1467(2) Å, b = 9.4641(2) Å and c = 7.4829(2) Å. Magnetic susceptibility and magnetization measurements reveal that strong antiferromagnetic exchange interactions prevail in Fe2F5(H taz) leading to a magnetic ordering transition at TN = 93 K. Analysis of low-temperature powder neutron diffraction data indicates that below TN, the Fe2+ sublattice is ferromagnetic, with a moment of 4.1(1) µB per Fe2+ at 2 K, but that an antiferromagnetic component of 0.6(3) µB cants the main ferromagnetic component of Fe3+, which aligns antiferromagnetically to the Fe2+ sublattice. The zero-field and in-field Mössbauer spectra give clear evidence of an excess of high-spin Fe3+ species within the structure and a non-collinear magnetic structure. This article is part of the theme issue 'Mineralomimesis: natural and synthetic frameworks in science and technology'.

Phytotoxic potential of Senna occidentalis (L.) Link extracts on seed germination and oxidative stress of Ipê seedlings.

Senna occidentalis is an invasive plant producing a series of allelochemicals that might inhibit the development of other plants. The objective of this study was to assess the phytotoxic effect of S. occidentalis extracts on the germination, development and antioxidant defence of the native species Tabebuia chrysotricha, T. pentaphylla, T. roseoalba and Handroanthus impetiginosus (Ipê species). We evaluated the effects of chemicals extracted from S. occidentalis on the germination rate, germination speed index (GSI) and biometric parameters of the test species under controlled conditions. The effect of the extracts on the pigment content, amount of H2 O2 and malondialdehyde (MDA), and the activity of the antioxidant enzymes in roots and leaves were also tested. Alkaloids, coumarins, phenols, saponins, free steroids and condensed tannins were present in all extracts of S. occidentalis, while catechins were present only in leaf and stem extracts. Stem and root extracts caused a growth reduction in all Ipê species and total inhibition of seed germination in T. chrysotricha and T. roseoalba. All target species showed an increase in H2 O2 and MDA in radicles and leaves. Oxidative stress contributed strongly to the morphological changes, such as seed blackening, thinning and darkening of radicle tips and reduction of biomass allocation in all Ipê species. Although there was activation of antioxidant defence mechanisms, such as an increase in activity of ascorbate peroxidase (APX) and peroxidase (POD) enzymes, the joint action of the allelochemicals caused phytotoxicity, leading to cell dysfunction in all Ipê species.

Cryotherapy: biochemical alterations involved in reduction of damage induced by exhaustive exercise.

When exercises are done in intense or exhaustive modes, several acute biochemical mechanisms are triggered. The use of cryotherapy as cold-water immersion is largely used to accelerate the process of muscular recovery based on its anti-inflammatory and analgesic properties. The present study aimed to study the biochemical effects of cold-water immersion treatment in mice submitted to exercise-induced exhaustion. Swiss albino mice were divided into 4 treatment groups: control, cold-water immersion (CWI), swimming exhaustive protocol (SEP), and SEP+CWI. Treatment groups were subdivided into times of analysis: 0, 1, 3, and 5 days. Exhaustion groups were submitted to one SEP session, and the CWI groups submitted to one immersion session (12 min at 12°C) every 24 h. Reactive species production, inflammatory, cell viability, and antioxidant status were assessed. The SEP+CWI group showed a decrease in inflammatory damage biomarkers, and reactive species production, and presented increased cell viability compared to the SEP group. Furthermore, CWI increased acetylcholinesterase activity in the first two sessions. The present study showed that CWI was an effective treatment after exercise-induced muscle damage. It enhanced anti-inflammatory response, decreased reactive species production, increased cell viability, and promoted redox balance, which could decrease the time for the recovery process.

Neuroimaging Findings of Zika Virus-Associated Neurologic Complications in Adults.

When the first suspected cases of neurologic disorders associated with the Zika virus were noticed in Brazil in late 2015, several studies had been conducted to understand the pathophysiology of the disease and its associated complications. In addition to its well-established association with microcephaly in neonates, the Zika virus infection has also been suggested to trigger other severe neurologic complications in adults, such as Guillain-Barré syndrome, radiculomyelitis, and meningoencephalitis. Hence, the Zika virus should be deemed a global threat that can cause devastating neurologic complications among individuals in all age ranges. The aim of this review was to further describe neuroimaging findings of Zika virus infection and associated neurologic complications found in adults.

Correlates of accelerometer-assessed physical activity in pregnancy-The 2015 Pelotas (Brazil) Birth Cohort Study.

Objective methods to measure physical activity (PA) have become available and widely used given the high degree of precision to evaluate PA. However, few studies have used accelerometers to measure PA during pregnancy, especially in low- and middle-income countries. We assessed overall PA, moderate, vigorous, and moderate-to-vigorous physical activity (MVPA) objectively measured among pregnant women and their correlates in a population-based study. PA was assessed for seven consecutive days using a raw triaxial wrist-worn accelerometer in women interviewed around 16 and 24 weeks of gestation in the 2015 Pelotas (Brazil) Birth Cohort Study. The average acceleration, which expresses overall PA, was presented in milli-g (1 mg = 0.001 g), and average time (min/day) spent in MVPA (>100 mg) was also analyzed in 5- and 10-min bouts. Analyses were performed using linear regression. In total, 2317 women were included in the analyses. Overall PA was 27.6 mg. Pregnant women spent on average 14 min/day in MVPA and 0.4 min in vigorous PA. Time spent in MVPA and total PA were inversely associated with years in school and income, and were lower among women receiving advice to not exercise. MVPA was also inversely associated with age, lower among women living with a partner, and higher among non-white women. The study indicated low levels of PA among pregnant women. The identified correlates may provide a framework to better understand factors influencing PA during pregnancy and thus inform future interventions.

Serum biochemical profile, enzymatic activity and lipid peroxidation in organs of laying hens fed diets containing cashew nut shell liquid.

The objective of this study was to evaluate the effect of feeding laying hens diets containing cashew nut shell liquid (CNSL) as a source of anacardic acid on the blood biochemical parameters as well as the enzymatic activity and lipid peroxidation of liver and tissues of the reproductive system (ovary, magnum, and uterus). A total of 216 Hisex White commercial laying hens were distributed randomly into six treatments, with six replicates of six birds. Treatments consisted of a diet without growth promoter (GP); a diet with GP; and diets without GP, with addition of increasing levels of CNSL (0.25, 0.50, 0.75 and 1.0%). Addition of CNSL to the diet did not affect the blood biochemical parameters (uric acid, creatinine, alanine aminotransferase, aspartate aminotransferase, total cholesterol, high density lipoproteins, low-density lipoproteins and triglycerides), the enzymatic activity (superoxide dismutase and nonprotein sulphydryl groups) in the organs (liver, ovary, magnum and uterus) or the peroxidation of lipids from the blood serum, liver, magnum and uterus (p > 0.05). However, the addition of 0.75% and 1.00% CNSL provided a lower thiobarbituric acid reactive substances content in the birds' ovary (p < 0.001) compared to birds of other treatments, whereas the treatment without the GP provided a higher value. Addition of up to 1% of the CNSL as a source of anacardic acid in the laying hens' diets does not influence blood biochemical parameters or the endogenous enzymatic activity in the liver, ovary, magnum and uterus, but affects the lipid peroxidation in the ovary, although the problem is reduced from the inclusion of 0.75% CNSL.

Cryotherapy: biochemical alterations involved in reduction of damage induced by exhaustive exercise

When exercises are done in intense or exhaustive modes, several acute biochemical mechanisms are triggered. The use of cryotherapy as cold-water immersion is largely used to accelerate the process of muscular recovery based on its anti-inflammatory and analgesic properties. The present study aimed to study the biochemical effects of cold-water immersion treatment in mice submitted to exercise-induced exhaustion. Swiss albino mice were divided into 4 treatment groups: control, cold-water immersion (CWI), swimming exhaustive protocol (SEP), and SEP+CWI. Treatment groups were subdivided into times of analysis: 0, 1, 3, and 5 days. Exhaustion groups were submitted to one SEP session, and the CWI groups submitted to one immersion session (12 min at 12°C) every 24 h. Reactive species production, inflammatory, cell viability, and antioxidant status were assessed. The SEP+CWI group showed a decrease in inflammatory damage biomarkers, and reactive species production, and presented increased cell viability compared to the SEP group. Furthermore, CWI increased acetylcholinesterase activity in the first two sessions. The present study showed that CWI was an effective treatment after exercise-induced muscle damage. It enhanced anti-inflammatory response, decreased reactive species production, increased cell viability, and promoted redox balance, which could decrease the time for the recovery process.

Lead(ii) soaps: crystal structures, polymorphism, and solid and liquid mesophases.

The long-chain members of the lead(ii) alkanoate series or soaps, from octanoate to octadecanoate, have been thoroughly characterized by means of XRD, PDF analysis, DSC, FTIR, ssNMR and other techniques, in all their phases and mesophases. The crystal structures at room temperature of all of the members of the series are now solved, showing the existence of two polymorphic forms in the room temperature crystal phase, different to short and long-chain members. Only nonanoate and decanoate present both forms, and this polymorphism is proven to be monotropic. At higher temperature, these compounds present a solid mesophase, defined as rotator, a liquid crystal phase and a liquid phase, all of which have a similar local arrangement. Since some lead(ii) soaps appear as degradation compounds in oil paintings, the solved crystal structures of lead(ii) soaps can now be used as fingerprints for their detection using X-ray diffraction. Pair distribution function analysis on these compounds is very similar in the same phases and mesophases for the different members, showing the same short range order. This observation suggests that this technique could also be used in the detection of these compounds in disordered phases or in the initial stages of formation in paintings.

Role of aquaporin-7 in ghrelin- and GLP-1-induced improvement of pancreatic ß-cell function after sleeve gastrectomy in obese rats.

BACKGROUND/OBJECTIVES: Glycerol is a key metabolite for lipid accumulation in insulin-sensitive tissues as well as for pancreatic insulin secretion. We examined the role of aquaporin-7 (AQP7), the main glycerol channel in ß-cells, and AQP12, an aquaporin related to pancreatic damage, in the improvement of pancreatic function and steatosis after sleeve gastrectomy in diet-induced obese rats. SUBJECTS/METHODS: Male Wistar obese rats (n=125) were subjected to surgical (sham operation and sleeve gastrectomy) or dietary (pair-fed to the amount of food eaten by sleeve-gastrectomized animals) interventions. The tissue distribution and expression of AQPs in the rat pancreas were analyzed by real-time PCR, western blotting and immunohistochemistry. The effect of ghrelin isoforms and glucagon-like peptide 1 (GLP-1) on insulin secretion, triacylglycerol (TG) accumulation and AQP expression was determined in vitro in RIN-m5F ß-cells. RESULTS: Sleeve gastrectomy reduced pancreatic ß-cell apoptosis, steatosis and insulin secretion. Lower ghrelin and higher GLP-1 concentrations were also found after bariatric surgery. Acylated and desacyl ghrelin increased TG content, whereas GLP-1 increased insulin release in RIN-m5F ß-cells. Sleeve gastrectomy was associated with an upregulation of AQP7 together with a normalization of the increased AQP12 levels in the rat pancreas. Interestingly, ghrelin and GLP-1 repressed AQP7 and AQP12 expression in RIN-m5F ß-cells. AQP7 protein was negatively correlated with intracellular lipid accumulation in acylated ghrelin-treated cells and with insulin release in GLP-1-stimulated ß-cells. CONCLUSIONS: AQP7 upregulation in ß-cells after sleeve gastrectomy contributes, in part, to the improvement of pancreatic steatosis and insulin secretion by increasing intracellular glycerol used for insulin release triggered by GLP-1 rather than for ghrelin-induced TG biosynthesis.

Neurologic complications of acute environmental injuries.

Environmental injuries can result in serious neurologic morbidity. This chapter reviews neurologic complications of thermal burns, smoke inhalation, lightning strikes, electric injury, near drowning, decompression illness, as well as heat stroke and accidental hypothermia. Knowing the pathophysiology and clinical presentation of such injuries is essential to proper management of primary and secondary medical complications. This chapter highlights the most frequently encountered neurologic injuries secondary to common environmental hazards, divided into the topics: injuries related to fire, electricity, water, and the extremes of temperature.

Platelet-activating factor (PAF) receptor as a promising target for cancer cell repopulation after radiotherapy.

A major drawback of radiotherapy is the accelerated growth of the surviving tumor cells. Radiotherapy generates a variety of lipids that bind to the receptor for platelet-activating factor, expressed by cells in the tumor microenvironment. In the present study, using the TC-1 tumor cell line, we found that irradiation induced a twofold increase in receptor expression and generated agonists of receptor. Irradiated cells induced a 20-fold increase in live TC-1 proliferation in vitro. Furthermore, subcutaneous co-injection of irradiated TC-1 cells with TC-1 expressing luciferase (TC-1 fluc+) markedly increased TC-1 fluc+ proliferation in a receptor-dependent way. Moreover we used a human carcinoma cell line not expressing the PAF receptor (KBM) and the same cell transfected with the receptor gene (KBP). Following co-injection of live KBP cells with irradiated KBM in RAG mice, the tumor growth was significantly increased compared with tumor formed following co-injection of live KBM with irradiated KBM. This tumor cell repopulation correlated with increased infiltration of tumor-promoting macrophages (CD206+). We propose that receptor represents a possible target for improving the efficacy of radiotherapy through inhibition of tumor repopulation.