The effect of arsenic, cadmium, mercury, and lead on the genotoxic activity of Boletaceae family mushrooms present in Serbia.

The aim of this study was to determine accumulation of heavy metals and metalloids which are widely distributed in the environment and in food chain using wild edible mushrooms belonging to the Boletaceae family mushrooms. In addition, methanol extracts of mushrooms were tested for in vitro protective effect by the cytochalasin-B blocked micronucleus (CBMN) assay using chromosome aberrations in human peripheral lymphocytes as a model. The genotoxic activity of methanol extracts prepared at 4 different concentrations (1, 2, 3 or 6 µg/ml) was examined using amifostine and mitomycin C as positive controls. Extracts of species B. regius and B. edulis exhibited the greatest reduction in the frequency of micronuclei (MN). Extract of B. regius at concentrations of 2 µg/ml showed the highest decrease in number of MN. In comparison, extract of mushroom B. edulis at a concentration of 3 µg/ml displayed less reduction. However, as heavy metals and metalloids are found in mushrooms, another aim was to examine whether these agents affected genotoxicity. Principal component analysis (PCA) identified clustering differences between control and heavy metals and metalloids groups and might explain the influence of heavy element content and genotoxic activity in mushrooms.

Host B chromosomes as potential sex ratio distorters of intestinal nematode infrapopulations in the yellow-necked mouse (Apodemus flavicollis).

The yellow-necked mouse, Apodemus flavicollis, can be considered as a model for genetic polymorphism produced by the frequent presence of supernumerary or B chromosomes (Bs). Host genetic background is rarely taken into account in studies of parasite sex ratio. The main aim of this study was to investigate the range of infrapopulation sex ratios for nematode parasites of the yellow-necked mouse and to determine which factors most influence variation in parasite sex ratios. Six nematode species found in the collected yellow-necked mice were analysed. We confirmed the predominant pattern of female-biased sex ratios in vertebrate parasite infrapopulations. The presence of B chromosomes in host genomes played an important role in infrapopulations of Heligmosomoides polygyrus, Syphacia stroma and Trichuris muris, as hosts with B chromosomes carried a higher proportion of males. The relative increase of males in infrapopulations could result from a shift in parasite life history strategy, induced by adaptation to the specific host genotypes (Bs present). In a meta-analysis with previously published data, the sex determination system was demonstrated to play a significant role in nematode sex ratio variation, as well as specific life history patterns, such as the place of egg hatching.

Is there a Host Sex Bias in Intestinal Nematode Parasitism of the Yellow-necked Mouse (Apodemus Flavicollis) at Obedska Bara Pond, Serbia?

Fifty-one yellow-necked mice from the Obedska bara locality were analysed for the presence of intestinal nematode parasites in order to assert whether there was a host sex bias in infection. Previous research indicated that males would be the more infected sex, either due to the immunosuppressive effect of testosterone or their different allocation of resources towards immune defence. Quantitative infection parameters were compared between host sexes for all nematode species and nematodes in general. In addition, the influence of host sex, age, total body length, body mass and presence of other nematode species on parasite abundance was analysed. No statistically significant differences between males and females were noted for any of the studied quantitative parameters, leading to an absence of sex-biased parasitism in this study.

Knowledge about cervical cancer, Pap test, and barriers to women's participation in screening in Belgrade, Serbia.

INTRODUCTION: Cervical cancer (CC) is a serious public health concern in Serbia, due to opportunistic screening still being in force, which led to twice higher than the average incidence rate of cervical cancer in Europe. Despite the fact that early detection and treatment services of CC are available at no additional cost, majority of women use inadequate screening services in Serbia. OBJECTIVE: This study aimed to examine the link between the knowledge about CC and Papanicolaou (Pap) test and perception of barriers to women's participation in CC screening. MATERIALS AND METHODS: The study included 300 women aged 21 to 69, with a place of residence in the city of Belgrade (Serbia), who were attending for their medical examination to the University Clinic of Gynecology and Obstetrics - "Narodni front", from June through December 2014. A survey instrument to collect data was an adapted questionnaire for the assessment of knowledge about and barriers to CC and Pap test. Patients were divided into three groups: a study group consisted of women attending irregularly (over three years), women who never participated in screening, and a control group that included women regularly participating in screening. RESULTS: Women regularly participating in screening (52.7%) had adequate knowledge about CC and Pap test, while women who irregularly (79.4%) or never participated (71.9%) did not have any adequate knowledge. There was a significant statistical difference between the CC and Pap test awareness in a group of respondents who regularly participated in comparison to respondents who irregularly or never participated in screening (x²= 27.772, p = 0.000). Regarding knowledge about human papillomavirus (HPV), 80% of women did not know that Pap test cannot be used for detection of HPV, as well as that abnormal Pap test result may be due to HPV (61.7%). Majority of women (93.7%) had poor knowledge about Pap test role in CC early detection and considered Pap test to be used to diagnose CC. The authors found a significant statistical correlation between participation of women in screening and barriers. Women who were irregular or never participated, had barriers such as: lack of time (F = 9.51; p = 0,000), difficult access to Healthcare facilities (F = 11.29; p = 0.000), lack of knowledge about the Pap test procedure (F = 21.27,p = 0.000), discomfort (F = 9.36; p = 0.000), and anxiety of Pap test results (F = 3.35; p = 0.036). Women who regularly participated did not have prejudice when choosing a gynecologist, unlike the other two groups that preferred a female gynecologist (F = 3.61; p = 0.028). CONCLUSION: This study showed that the level of knowledge about CC and Pap test in women is an important factor associated with regular participation in screening. It is necessary to take educational measures in order to raise awareness of women regarding risk factors, as well as to overcome fear and shame, with the ultimate aim to reduce frequency and mortality rate caused by CC in Serbia.

Resurgence of measles in Serbia 2010-2011 highlights the need for supplementary immunization activities.

Between December 2010 and August 2011 an outbreak of measles occurred in Serbia with 363 reported cases. Sera and/or nose/throat swabs were collected from 193 patients and tested for measles-specific IgM antibodies by ELISA and viral RNA by RT-PCR, respectively. Epidemiological data were obtained from the surveillance database of the Institute of Public Health of Serbia. Of the 363 cases involved in the outbreak, 113 were laboratory confirmed. More than one third of the patients were hospitalized (n = 130, 35·8%) and for 15 (4·1% of the reported outbreak cases) the infection was complicated by pneumonia. Mostly pre-school children aged ⩽4 years (37·8%) and adults aged ⩾30 years (27·3%) were affected. The majority of patients belonged to the Roma population with a preponderance of female cases (57·0%). Nearly 94% of the patients were either unvaccinated or of unknown vaccination status. The main outbreak virus was the D4-Hamburg strain. The outbreak in Serbia occurred after several years of very low measles incidence despite a high routine immunization coverage in the general population, suggesting that special efforts to identify and vaccinate susceptible population groups are required even in countries with apparently good disease control.

Diversity of nematodes in the yellow-necked field mouse Apodemus flavicollis from the Peripannonic region of Serbia.

Up to six nematode species were identified from 86 specimens of the yellow-necked field mouse Apodemus flavicollis from three mountainous localities known as Avala, Cer and Liskovac in Serbia. The highest prevalence of infection of 97% was recorded from Mt. Avala. Only one nematode species, Syphacia frederici, occurred in all three localities. There was complete overlap in nematode species from Mts. Avala and Liskovac, whereas the taxonomic distinctness of Mt. Cer was seen in the presence of the insect-transmitted species Rictularia proni. Locality was a statistically significant factor in all the best-fitted generalized linear models of variation in abundances. The highest level of both species richness and parasite alpha diversity (Shannon's H= 1.47) was found in the easternmost Mt. Liskovac, whereas the diversity indices were lowest for the westernmost Mt. Cer (Shannon's H= 0.48). In view of this geographical difference, the beta diversity indices were calculated along a west to east longitudinal gradient.

Clinical implementation of cardiac resynchronization therapy-regional disparities across selected ESC member countries.

BACKGROUND: The present analysis aimed to estimate the penetration of cardiac resynchronization therapy (CRT) on the basis of the prevalence and incidence of eligible patients in selected European countries and in Israel. METHODS AND RESULTS: The following countries were considered: Italy, Slovakia, Greece, Israel, Slovenia, Serbia, the Czech Republic, Poland, Romania, Hungary, Ukraine, and the Russian Federation. CRT penetration was defined as the number of patients treated with CRT (CRT patients) divided by the prevalence of patients eligible for CRT. The number of CRT patients was estimated as the sum of CRT implantations in the last 5 years, the European Heart Rhythm Association (EHRA) White Book being used as the source. The prevalence of CRT indications was derived from the literature by applying three epidemiologic models, a synthesis of which indicates that 10% of heart failure (HF) patients are candidates for CRT. HF prevalence was considered to range from 1% to 2% of the general population, resulting in an estimated range of prevalence of CRT indication between 1000 and 2000 patients per million inhabitants. Similarly, the annual incidence of CRT indication, representing the potential target population once CRT has fully penetrated, was estimated as between 100 and 200 individuals per million. The results showed the best CRT penetration in Italy (47-93%), while in some countries it was less than 5% (Romania, Russian Federation, and Ukraine). CONCLUSION: CRT penetration differs markedly among the countries analyzed. The main barriers are the lack of reimbursement for the procedure and insufficient awareness of guidelines by the referring physicians.

Evaluation of the self-assessment knowledge regarding cardiopulmonary resuscitation in medical students at the University of Belgrade.

OBJECTIVE: Cardiopulmonary resuscitation (CPR) is a vital skill that can improve the outcome of patients with sudden cardiac arrest. To raise awareness about CPR some countries have introduced an obligatory First Aid Course (FAC), usually done parallelly to a driver's license (DL). While expected of doctors to know CPR, the curriculum of some medical schools does not seem to have enforced measures to improve that knowledge. The aim was to have students self-evaluate their current knowledge of CPR, comparing it before university and whether it improved during their studies. SUBJECTS AND METHODS: A cross-sectional study was conducted in October 2020 using an anonymous questionnaire among students at the Faculty of Medicine in Belgrade (studies in English). RESULTS: A total of 172 (66.7%) students possessed a DL, of which 39.8% felt they were ready, 45.8% felt neutral, and 14.4% felt unable to perform CPR. The total number of students that completed a FAC during their studies was 165. Analysis was performed on the ability assessment data after the first FAC during studies, comparing it to FAC for DL and assessments at the end of studies. No statistically significant difference was observed in the level of self-reported ability to perform CPR, while a statistically significant difference was found in ability assessments when comparing only the FAC for the DL, and the one after the first FAC during medical studies, with students feeling more prepared after the FAC for DL. Across the sample, 90.2% of the students wished they had more CPR training during their medical studies. CONCLUSIONS: From this study, it may conclude that students wish and need more CPR training in their curriculum.

Correlation of human papilloma virus infection with cytology, colposcopy and histopathological examination of the bioptic tissue in low- and high-grade intraepithelial lesions.

INTRODUCTION: It is now believed that the majority of cervical cancer is preceded by long-term infection with high-risk types of the human papilloma virus (HPV). The presence of HPV high-risk types (HR-HPV) in the cells of intraepithelial change multiplies the possibility of its progressive development to high-grade cervical precancer and invasive disease. AIM: This study examined the correlation of HPV infection with cytology, colposcopy, and histopathological examination of the bioptic tissue in low- and high-grade cervical lesions. MATERIALS AND METHODS: This research was conducted as a study section. Data collection was performed during a ten-year period, at the University Clinic of Gynecology and Obstetrics - Narodni Front in Belgrade (Serbia). The basic set included 1,927 patients. Colposcopy, cytology, histopathology, and HPV test verification was made in all patients. Statistical analysis was performed using the SPSS program, version 17.0. Contingency tables were used to assess the degree of correlation of variables and chi-square test was used to determine the level of statistical significance in this study. A p value < 0.05 was considered statistically significant. RESULTS: Among 1,927 women studied, 635 (32.95 %) had abnormal cytological findings and among these, 272 (42.83%) were HR-HPV positive. There was a statistical difference between colposcopic and cytological findings in patients with HR-HPV (x2 = 35.33, p = 0.000). There was also a statistically significant difference between histophatological and colposcopical findings in patients with HR-HPV (x2 = 10,171, p = 0.001). Only HR-HPV types 16 and 18 showed a statistical significance compared to histopathological findings, unlike other HR-HPV. An important finding was that the authors found an abnormal colposcopy in 93.30% patients with low-grade intraepithelial neoplasia and 68.05% patients with low-grade squamous intraepithelial lesion (LSIL) had normal cytology and was 70.15 % HR-HPV negative. CONCLUSION: The findings imply that among high-grade intraepithelial neoplasias, the authors found a high presence of HPV type 16 and 18, and a statistical significant presence of HPV 16 in low-grade intraepithelial neoplasia, unlike other HR-HPV types in low-grade intraepithelial findings. The authors found a significant statistical correlation with abnormal cytology and presence of HPV type 16 in both groups (LSIL and high-grade squamous intraepithelial lesion (HSIL). The authors also found an abnormal colposcopy in 93.30% of patients with low-grade intraepithelial neoplasia, while 68.05% of patients with LSIL had normal cytology and were HR-HPV negative in 70.15% of the cases.

Predicting no-reflow phenomenon prior to primary percutaneous coronary intervention using a novel probability risk score derived from clinical and angiographic parameters.

OBJECTIVE: We aimed to create a clinically usable probability risk score for prediction of no-reflow (NRF) phenomenon prior to primary percutaneous coronary intervention (PPCI). PATIENTS AND METHODS: This single-center and retrospective study included 1254 patients with acute ST-segment elevation myocardial infarction (STEMI) who underwent PPCI. Patients were randomly assigned into two groups in the ratio 2:1, the derivation dataset (n=840) and validation dataset (n=414). Independent predictors of NRF were identified and combined to create a prediction model using univariate and multivariate regression analysis in the derivation dataset. The risk score was tested and validated by calculating area under the receiver operating characteristic (ROC) curves in the derivation and validation datasets, respectively. RESULTS: Five significant, independent predictors of NRF were identified: age ≥ 65 years (odds ratio [OR]: 2.473, 95% confidence interval [CI]: 0.389-1.484, p < 0.01), heart rate ≥ 89 bpm (odds ratio [OR]: 1.622, 95% confidence interval [CI]: 0.024-0.945, p < 0.05), Killip class ≥ II (odds ratio [OR]: 1.914, 95% confidence interval [CI]: 0.024-1.306, p < 0.01), total ischemic time ≥ 268 min (odds ratio [OR]: 2.652, 95% confidence interval [CI]: 0.493-1.565, p < 0.01), and thrombus burden G≥4 (odds ratio [OR]: 8.351, 95% confidence interval [CI]: 0.344-15.901, p < 0.01). The risk score was created combining these predictors with assigned points. The overall score ranged from 0 to 17 points. The optimal cutoff value of the risk score was 11 points (area under curve [AUC]: 0.772, 95% confidence interval [CI]: 0.729-0.815, sensitivity 71.21%, specificity 70.34%, positive predictive value 30.92%, negative predictive value 92.91%, p < 0.001). The ROC curve for the validation group showed good discriminant power. CONCLUSIONS: We developed a novel risk score based on five clinical and angiographic parameters, which might be a useful clinical tool for prediction of NRF in STEMI patients prior to PPCI with an acceptable accuracy.

Chronic cognitive sequelae after traumatic brain injury are not related to growth hormone deficiency in adults.

OBJECTIVE: The objective of the study was to asses the possible influence of hypothalamo-pituitary deficiencies, and growth hormone (GH) deficiency in particular, on cognition in adult patients with traumatic brain injury (TBI). TBI is a recently identified risk factor for cognitive deficits and hypopituitarism. Even the patients with favorable outcome after TBI may present with persistent bodily, psychosocial, and cognitive impairments, resembling patients with untreated partial or complete pituitary insufficiency. DESIGN: We performed retrospective and cross-sectional study of endocrine and cognitive function in TBI in 61 patients (aged 37.7 +/- 1.7 years) of both sexes (44 m,17 f), at least 1 year after TBI (3.9 +/- 0.6 years). Serum insulin-like growth factor 1 (IGF-I), thyroxin, thyroid-stimulating hormone (TSH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), testosterone (in men), prolactin, and cortisol were measured, and GH secretion was assessed by growth hormone releasing hormone (GHRH) + growth hormone releasing peptide-6 (GHRP-6) test. Cognitive function was assessed by using a standard neuropsychological battery. RESULTS: GH deficiency (GHD) and GH insufficiency (GHI) were found in 20 patients (32.8%). After adjustment for confounders [age, body mass index (BMI), education level, time elapsed from TBI], there were no significant differences in results of neuropsychological tests between patients with TBI with GHD, GHI, and normal GH secretion. There were no correlations of neuropsychological variables with stimulated peak GH secretion or IGF-I level. CONCLUSIONS: GHD persists long after the TBI, independently of trauma severity and age at traumatic event. GH secretion is more sensitive to TBI than other pituitary hormones. No evidence is found for an association of cognitive function impairment and somatotropic axis impairment in adult patients tested more than 1 year after the TBI.

Analysis of cutaneous melanoma in the province of Vojvodina.

PURPOSE: To analyse the incidence and mortality of melanoma in the province of Vojvodina - the north part of Serbia- from the epidemiologic and clinical point of view. PATIENTS AND METHODS: In this retrospective study, we used databases of the Cancer Registry of Vojvodina, Oncology Institute of Vojvodina in Sremska Kamenica; Clinical Centre of Vojvodina in Novi Sad; Institute of Public Health of Vojvodina in Novi Sad; and Institute of Public Health of Serbia in Belgrade. RESULTS: The incidence and mortality of melanoma in Vojvodina is permanently increasing over the last three decades. The number of newly diagnosed and deceased patients was higher in men and in women in Vojvodina than in central Serbia. Considering the incidence rate, the region of Vojvodina would be placed in the middle of the European countries. The results are more unfavorable with mortality, especially in male population, similar to the range of higher mortality rates among European countries. CONCLUSION: These upsetting facts call for improvement of primary and secondary prevention. Education of the population, continuous efforts to recognize groups of population at high risk for developing melanoma and detection of early phases of the disease increases the chances for cure and significantly reduces treatment costs.

Serum N-acetyl-beta-D-glucosaminidase profiles in type 1 diabetes secondary complications: causes of changes and significance of determination.

The connection between changes in the activity of serum N-acetyl-beta-D-glucosaminidase (NAG, E.C.3.2.1.30) and iso-enzymes and degree of secondary complications was analyzed in four groups of type 1 diabetic patients (n=69): without complications (n=22); with retinopathy (n=16); with retinopathy and polyneuropathy (n=13), and with retinopathy, neuropathy, and nephropathy (n=18). In all groups statistically significant higher (P<0.001) percent fraction of A form (83.84+/-6.09, 84.37+/-5.74, 81.76+/-6.02, 76.37+/-7.38%, resp.) and lower (P<0.001, P<0.01) fraction of B form (15.87+/-5.65, 15.66+/-5.74, 18.33+/-5.98, 23.63+/-7.38, resp.) in total NAG compared with the control (A=69.38+/-4.79%, B=30.61+/-4.78%) were found. The differences in A as well as B forms between diabetic groups were not statistically significant. Significant strong positive correlations between total NAG and glycemia (0.494-0.623), total NAG and A form (0.934-0.966), and A form and glycemia (0.512-0.638) were found in all groups. No correlation was found between the fractions of B and A forms, except in the fourth group. The A form of diabetic patients in the fourth group was more acidic compared with the control and other diabetic groups. It was concluded that the changes in serum NAG and iso-enzymic profiles in diabetes are the consequence of its increased exocytose, especially of the A form, in hyperglycemia and posttranslational modifications of iso-enzymes. The total activity of serum NAG and iso-enzymic profiles cannot be used for monitoring the development and distinction of type 1 diabetes secondary complications.

Secondary metabolites of Seseli rigidum: Chemical composition plus antioxidant, antimicrobial and cholinesterase inhibition activity.

Extracts of different polarity obtained from various plant parts (root, leaf, flower and fruit) of Seseli rigidum were studied by different antioxidant assays: DPPH and ABTS radical scavenging activity, by total reducing power method as well as via total content of flavonoids and polyphenols. Essential oils of all plant parts showed weak antioxidant characteristics. The inhibitory concentration range of the tested extracts, against bacteria Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus cereus, and fungi Candida albicans and Aspergillus niger was 0.01-1.50 mg/mL and of a microbicidal 0.02-3.00 mg/mL. In the interaction with cholinesterase, all essential oils proved effective as inhibitors. The highest percentage of inhibition versus human and horse cholinesterase was shown by root essential oil (38.20% and 48.30%, respectively) among oils, and root hexane extract (40.56% and 50.65% respectively). Essential oils and volatile components of all plant parts were identified by GC, GC-MS and headspace/GC-MS. Statistical analysis of the ensemble of results showed that the root essential oil composition differed significantly from essential oils of other parts of the plant. Taking into account all of the studied activities, the root hexane extract showed the best overall properties. By means of high performance liquid chromatography coupled to high resolution mass spectrometry, the 30 most abundant constituents were identified in extracts of different polarity. The presence of identified constituents was linked to observed specific biological activities, thus designating compounds potentially responsible for each exhibited activity.

Comparative pharmacological and functional analysis of the human dopamine D4.2 and D4.10 receptor variants.

The human dopamine D4 receptor is a D2-like receptor which is a target for most common neuroleptics. Previous investigations have shown that this receptor displays a large polymorphic variation in the third intracellular loop involving a variable number of direct imperfect tandem repeats (VNTR) of 16 amino acids. The shortest and longest repeat variants reported to date contain two and 10 repeat units (D4.2 and D4.10). No major pharmacological differences have been reported for the most common variants of this receptor (D4.2, D4.4 and D4.7), although the D4.7 was reported by us to display a slightly lower potency for dopamine in functional assays. Direct pharmacological and functional comparison of the longest and shortest variants in this study suggest no major discrepancies in pharmacological or functional profile between both receptors. Both receptors display, on average, a 15-fold and 90-fold lower potency for epinephrine and norepinephrine, respectively, compared with dopamine. We observed small increases in functional potency and affinity for dopamine and quinpirole at the D4.10 receptor variant compared with the D4.2 receptor. Our data indicate that there is no direct relationship between the length of the polymorphism and changes in pharmacology or functional activity. These findings are a suitable caution against the arbitrary pooling of D4 receptor VNTR genotypes in genetic studies, based on length.

Modulation of humoral immune response by central administration of leucine-enkephalin: effects of mu, delta and kappa opioid receptor antagonists.

The effect of leucine-enkephalin (Leu-Enk) on primary humoral immune response was investigated following intracerebroventricular (i.c.v.) administration of the peptide in the rat. Leu-Enk stimulated plaque-forming cell (PFC) response in rats i.c.v. injected with 0.1 and 1 micrograms/kg, whereas does of 20 and 50 micrograms/kg exerted immunosuppressive effects. I.c.v. treatment of rats with delta opioid receptor antagonist ICI 174,864 and kappa opioid receptor antagonist nor-binaltorphimine (nor-BNI) blocked stimulation and suppression of PFC response induced by Leu-Enk, respectively. The mu opioid receptor antagonist beta-funaltrexamine (beta-FNA) reversed both immunomodulatory effects produced by Leu-Enk. Since beta-FNA alone had no effect on PFC response (unlike ICI 174,864 and nor-BNI), these data showed that central effects of Leu-Enk on PFC response were mediated by brain mu opioid receptors, and suggested a possible involvement of delta and kappa opioid receptors.

Acute erythremic myelosis (DiGuglielmo) following atypical aplastic anemia.

A patient presented with acute erythromyelosis (DiGuglielmo) which was developed after 3 yr of aplastic anemia. Aplastic anemia differed from the classical form, since erythroid cells and megakaryocytes were relatively preserved in the bone marrow. Treatment with androgens induced the increase of hematocrit and reticulocyte as well as general improvement. The sudden appearance of hemorrhagic syndrome due to thrombocytopenia was associated with aggravation of anemia and granulocytopenia. In the bone marrow, giant multinuclear proerythroblasts with bizarre nuclear morphology and PAS positivity with coarse granules was found. Serum erythropoietin (Ep) level was high. Bone marrow cells culture in vitro revealed two types of erythroid colonies: typical and giant multinuclear cells, both benzidine-positive. The number of colonies was irrespective to the Ep dose. "Autonomous" Ep independent growth of these colonies was also demonstrated. The number of colonies was more than 3 times higher per number of cells seeded when compared to normals, which indicated malignant proliferation and Ep independent growth. Treatment with 6-mercaptopurine and transfusions was without effect and the patient died after 15 days with signs of cerebral bleeding.

Short- and long-term heterologous sensitization of adenylate cyclase by D4 dopamine receptors.

The D4 dopamine receptor, a member of the D2-like dopamine receptor family, may be important in the etiology and treatment of schizophrenia. The present study was designed to examine the effects of dopamine agonist exposure on adenylate cyclase activity in HEK293 cells stably expressing recombinant-D4 receptors. Two hour pretreatment with dopamine receptor agonists resulted in heterologous sensitization of forskolin-stimulated cyclic AMP accumulation in intact cells expressing the D4.2, D4.4, or D4.7 dopamine receptor variant. The potency and efficacy of dopamine for sensitization of cyclic AMP accumulation was comparable at all D4 receptor variants. D4 dopamine receptor-mediated sensitization was blocked by the D4 antagonist, clozapine, and prevented by overnight pretreatment with pertussis toxin, implying a role for Gi/Go proteins in heterologous sensitization. Further, long-term (18 h) agonist exposure resulted in a greater degree of sensitization of forskolin-stimulated cyclic AMP accumulation in both intact cells and membrane preparations of cells expressing the D4 receptor, compared to 2 h agonist exposure, without altering the density of the receptors. In addition, long-term agonist exposure decreased the abundance of Gialpha without altering the abundance of Gsalpha, whereas short-term agonist treatment had no effect on the immunoreactivity of either G protein. In summary, long-term agonist-induced sensitization of adenylate cyclase by the D4 receptor may involve mechanisms that do not contribute to short-term sensitization.

Effect of Met-enkephalin and opioid antagonists on rat macrophages.

Effects of Met-enkephalin (Met-ENK) and opioid antagonists on H2O2 release by peritoneal macrophages from DA and AO rats were investigated. Met-ENK increased and decreased H2O2 production by macrophages of DA and AO rats, respectively. These effects were antagonized by low, but not high, concentrations of naloxone and ICI 174864. High concentrations of both antagonists directly modulated H2O2 release and retained the strain-related differences seen with Met-ENK. The results showed direct, strain- and dose-dependent, effects of Met-ENK, naloxone, and ICI 174864 on rat macrophage function.

Multifocal plasmacytoma of hand and foot bones.

Simultaneous occurrence of localized plasmacytomas of both hands and feet has not been reported so far. Here we report a 40-year old female patient, who had at presentation pain and deformity. Of hands and feet, with numerous cystic lytic lesions of phalangeal, metacarpal and metatarsal bones, detected by X-rays. The biopsy of the affected bone showed moderately differentiated plasmacytoma of lambda light chain type (lambda-LC). Serum and urine biochemical analysis revealed the existence of lambda LC monoclonal component. The patient was treated by local radiotherapy and subsequent systemic chemotherapy, which consisted of 3 cycles of the M-2 protocol and 7 cycles of melphalan-prednisone. Five years after the diagnosis, the absence of plasmacytoma was confirmed by puncture biopsy of the left hand phalanx. Monoclonal protein in serum and urine was not detected.