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1.
Aust Vet J ; 101(4): 142-152, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36635984

RESUMO

Numerous culture-based diagnostics are available on the Australian and international markets for on-farm detection of bacterial pathogens in milk. Use of such diagnostics may provide an opportunity to improve the prudent use of antimicrobials in udder health management. Farms are low-resource settings in terms of diagnostic microbiology capacity. The World Health Organisation has identified criteria for the evaluation of diagnostic tests in low resource settings based on Accuracy, Sensitivity, Specificity, User-friendliness, being Rapid or Robust, Equipment-free and being Deliverable (ASSURED). Here, we review how those criteria can be interpreted in the context of microbiological diagnosis of mastitis pathogens, and how on-farm diagnostics that are currently available in Australia perform relative to ASSURED criteria. This evaluation identifies multiple trade-offs, both with regard to scientific criteria and with regards to convenience criteria. More importantly, the purpose of testing may differ between farms, and test performance should be evaluated relative to its intended use. The ability of on-farm mastitis diagnostics to inform mastitis treatment decision-making in a timely and cost-effective manner depends not just on test characteristics but also on farm-specific pathogen prevalence, and on the farm enterprise's priorities and the farm manager's potential courses of action. With most assay evaluations to date conducted in professional laboratories, there is a surprising dearth of information on how well any of the diagnostic tests perform on-farm and, indeed, of the on-farm decision-making processes that they aim to inform.


Assuntos
Anti-Infecciosos , Doenças dos Bovinos , Mastite Bovina , Bovinos , Feminino , Animais , Fazendas , Mastite Bovina/diagnóstico , Austrália , Leite/microbiologia , Indústria de Laticínios
2.
J Biol Regul Homeost Agents ; 31(2 Suppl. 2): 179-182, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28702979

RESUMO

Successful embryo implantation requires good quality embryo but also needs a receptive endometrium site. In our clinical practice, we daily verify that an adequate endometrial growth is reached for successful implantation. To understand whether platelet rich plasma (PRP) can improve endometrium thickness and performance, PRP treatment was carried out after at least three of the classic medical protocols currently in use had been unsuccessfully adopted. Eight patients with more than 3 cryo-transfers cancelled because of failure of endometrial growth, defined as endometrium less than 6 mm, with negative hysteroscopic screening for endometrial pathology, and with negative bacteriologic screening, before present and all previous treatment, were selected to undergo PRP treatment. In 7 out of 8 treatments, an endometrial thickness greater than 6.5 mm (mean 6.9 mm) was reached, with endometrial three-layer pattern, before progesterone administration and embryo transfer was performed. In 6 out of 7 patients, who underwent embryo transfer, beta-HCG were positive, with 2 biochemical abortions, one miscarriage at 6-week pregnancy, two babies born and one drop-out. In this study, 8 patients had extraordinarily poor endometrial quality, and the endometrium was non-responsive to conventional estrogenic therapy, resulting in cycle cancellation. After application of PRP, the endometrial thickness was satisfactory in all the patients except one. Of these, beta-HCG was positive in 6 women, the pregnancy was progressing normally in 2 women, and one had an early miscarriage. We can suppose that the multiple implantation failures were caused by inefficient expression adhesion molecules, which can hypothetically be more represented after PRP application.

3.
HNO ; 62(4): 282-5, 2014 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-23744084

RESUMO

BACKGROUND: Malignant tumors occur in up to 15 % of patients with paraneoplastic syndromes. The temporal association between malignancy and paraneoplasia is variable. Dermatomyositis belongs to the facultative cutaneous paraneoplasia. CASE REPORT: A patient presented with a cervical swelling and preexisting dermatomyositis. Staging revealed a tonsillar carcinoma with cervical, mediastinal and bone metastasis, and meningeal carcinomatosis. Systemic intrathecal chemotherapy was initiated. CONCLUSION: Dermatomyositis has only been described four times worldwide as a paraneoplastic disease with tonsillar carcinoma. Upon occurrence of a paraneoplastic syndrome, an intensive search for tumours is required at regular intervals until the primary tumor is diagnosed.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/terapia , Dermatomiosite/diagnóstico , Síndromes Paraneoplásicas/diagnóstico , Síndromes Paraneoplásicas/terapia , Neoplasias Tonsilares/diagnóstico , Neoplasias Tonsilares/terapia , Dermatomiosite/prevenção & controle , Evolução Fatal , Humanos , Masculino , Pessoa de Meia-Idade
5.
Naunyn Schmiedebergs Arch Pharmacol ; 386(11): 991-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23832378

RESUMO

Ajmaline is a class Ia anti-arrhythmic compound that is widely used for the diagnosis of Brugada syndrome and the acute treatment of atrial or ventricular tachycardia. For ajmaline, inhibitory effects on a variety of cardiac K(+) channels have been observed, including cardiac Kv1 and Kv4 channels. However, the exact pharmacological properties of channel blockade have not yet been addressed adequately. Using two different expression systems, we analysed pharmacological effects of ajmaline on the potassium channels Kv1.5 and Kv4.3 underlying cardiac I Kur and I to current, respectively. When expressed in a mammalian cell line, we find that ajmaline inhibits Kv1.5 and Kv4.3 with an IC50 of 1.70 and 2.66 µM, respectively. Pharmacological properties were further analysed using the Xenopus expression system. We find that ajmaline is an open channel inhibitor of cardiac Kv1.5 and Kv4.3 channels. Whereas ajmaline results in a mild leftward shift of Kv1.5 activation curve, no significant effect on Kv4.3 channel activation could be observed. Ajmaline did not significantly affect channel inactivation kinetics. Onset of block was fast. For Kv4.3 channels, no significant effect on recovery from inactivation or channel deactivation could be observed. Furthermore, there was no use-dependence of block. Taken together, we show that ajmaline inhibits cardiac Kv1.5 and Kv4.3 channels at therapeutic concentrations. These data add to the current understanding of the electrophysiological basis of anti-arrhythmic action of ajmaline.


Assuntos
Ajmalina/farmacologia , Antiarrítmicos/farmacologia , Canal de Potássio Kv1.5/antagonistas & inibidores , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio Shal/antagonistas & inibidores , Animais , Células CHO , Cricetulus , Técnicas In Vitro , Canal de Potássio Kv1.5/fisiologia , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Canais de Potássio Shal/fisiologia , Xenopus
6.
Naunyn Schmiedebergs Arch Pharmacol ; 386(9): 795-804, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23666493

RESUMO

Duloxetine is a selective serotonin-noradrenaline reuptake inhibitor approved for treatment of major depressive disorder. So far, duloxetine has been found to be well tolerated and reported cardiac side effects were negligible. However, pharmacological effects on cardiac hERG channels have not been properly addressed yet. hERG channels were expressed in Xenopus oocytes and a human embryonic kidney (HEK) cell line. Currents were measured using voltage clamp and patch clamp techniques. Channel surface expression was quantified using Western blot analysis. We found that duloxetine inhibits heterologously expressed hERG channels in a concentration-dependent manner, yielding an IC50 of 142.8 µM in Xenopus oocytes. Inhibitory effects were even more pronounced when using a mammalian cell line resulting in a 34 or 59% current decrease by 10 or 30 µM duloxetine, respectively. Duloxetine did not affect channel activation or inactivation kinetics. However, channel deactivation was accelerated by duloxetine. We further showed that inhibition occurs in the open and inactivated, but not closed, states. There was no frequency dependence of block. However, effects of duloxetine were significantly attenuated when using the hERG pore mutants Y652A and F656A. Subacute effects of duloxetine on hERG channel expression were analyzed using the Western blot technique. We found that incubation with duloxetine results in a concentration-dependent decrease of channel surface expression. Whereas inhibitory effects of duloxetine seem negligible under therapeutically relevant concentrations, hERG block should be considered in cases of duloxetine overdose and when administering duloxetine to patients susceptible to drug-induced QT prolongation.


Assuntos
Inibidores da Captação Adrenérgica/farmacologia , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Tiofenos/farmacologia , Animais , Cloridrato de Duloxetina , Canal de Potássio ERG1 , Canais de Potássio Éter-A-Go-Go/fisiologia , Células HEK293 , Coração/fisiologia , Humanos , Oócitos/efeitos dos fármacos , Oócitos/fisiologia , Xenopus laevis
7.
Br J Pharmacol ; 165(5): 1467-75, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21838752

RESUMO

BACKGROUND AND PURPOSE: TASK1 (K(2P)3.1) two-pore-domain K(+) channels contribute substantially to the resting membrane potential in human pulmonary artery smooth muscle cells (hPASMC), modulating vascular tone and diameter. The endothelin-1 (ET-1) pathway mediates vasoconstriction and is an established target of pulmonary arterial hypertension (PAH) therapy. ET-1-mediated inhibition of TASK1 currents in hPASMC is implicated in the pathophysiology of PAH. This study was designed to elucidate molecular mechanisms underlying inhibition of TASK1 channels by ET-1. EXPERIMENTAL APPROACH: Two-electrode voltage clamp and whole-cell patch clamp electrophysiology was used to record TASK1 currents from hPASMC and Xenopus oocytes. KEY RESULTS: ET-1 inhibited TASK1-mediated I(KN) currents in hPASMC, an effect attenuated by Rho kinase inhibition with Y-27632. In Xenopus oocytes, TASK1 current reduction by ET-1 was mediated by endothelin receptors ET(A) (IC(50) = 0.08 nM) and ET(B) (IC(50) = 0.23 nM) via Rho kinase signalling. TASK1 channels contain two putative Rho kinase phosphorylation sites, Ser(336) and Ser(393) . Mutation of Ser(393) rendered TASK1 channels insensitive to ET(A) - or ET(B)-mediated current inhibition. In contrast, removal of Ser(336) selectively attenuated ET(A) -dependent TASK1 regulation without affecting the ET(B) pathway. CONCLUSIONS AND IMPLICATIONS: ET-1 regulated vascular TASK1 currents through ET(A) and ET(B) receptors mediated by downstream activation of Rho kinase and direct channel phosphorylation. The Rho kinase pathway in PASMC may provide a more specific therapeutic target in pulmonary arterial hypertension treatment.


Assuntos
Endotelina-1/metabolismo , Proteínas do Tecido Nervoso/antagonistas & inibidores , Canais de Potássio de Domínios Poros em Tandem/antagonistas & inibidores , Quinases Associadas a rho/metabolismo , Animais , Células Cultivadas , Feminino , GTP Fosfo-Hidrolases/metabolismo , Humanos , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/fisiopatologia , Potenciais da Membrana/genética , Potenciais da Membrana/fisiologia , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/fisiologia , Mutação , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/fisiologia , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Fosforilação , Canais de Potássio de Domínios Poros em Tandem/genética , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Artéria Pulmonar/metabolismo , Artéria Pulmonar/fisiologia , Receptor de Endotelina A/metabolismo , Receptor de Endotelina B/metabolismo , Transdução de Sinais , Vasoconstrição/genética , Vasoconstrição/fisiologia , Xenopus laevis , Quinases Associadas a rho/antagonistas & inibidores
8.
J Mol Cell Cardiol ; 51(5): 722-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21803046

RESUMO

The transient outward current I(to) is an important determinant of the early repolarization phase. I(to) and its molecular basis Kv4.3 are regulated by adrenergic pathways including protein kinase C. However, the exact regulatory mechanisms have not been analyzed yet. We here analyzed isoenzyme specific regulation of Kv4.3 and I(to) by PKC. Kv4.3 channels were expressed in Xenopus oocytes and currents were measured with double electrode voltage clamp technique. Patch clamp experiments were performed in isolated rat cardiomyocytes. Unspecific PKC stimulation with PMA resulted in a reduction of Kv4.3 current. Similar effects could be observed after activation of conventional PKC isoforms by TMX. Both effects were reversible by pharmacological inhibition of the conventional PKC isoenzymes (Gö6976). In contrast, activation of the novel PKC isoforms (ingenol) did not significantly affect Kv4.3 current. Whereas TMX-induced PKC activation was not attenuated inhibition of PKCß, inhibition of PKCα with HBDDE prevented inhibitory effects of both PMA and TMX. Accordingly, stimulatory effects of PMA and TMX could be mimicked by the α-isoenzyme selective PKC activator iripallidal. Further evidence for the central role of PKCα was provided with the use of siRNAs. We found that PKCα siRNA but not PKCß siRNA abolished the TMX induced effect. In isolated rat cardiomyocytes, PMA dependent I(to) reduction could be completely abolished by pharmacologic inhibition of PKCα. In summary we show that PKCα plays a central role in protein kinase C dependent regulation of Kv4.3 current and native I(to). These results add to the current understanding of isoenzyme selective ion channel regulation by protein kinases.


Assuntos
Potenciais da Membrana/fisiologia , Miócitos Cardíacos/metabolismo , Oócitos/metabolismo , Proteína Quinase C-alfa/metabolismo , Canais de Potássio Shal/metabolismo , Transdução de Sinais , Animais , Carbazóis/farmacologia , Inibidores Enzimáticos/farmacologia , Feminino , Isoenzimas/genética , Isoenzimas/metabolismo , Potenciais da Membrana/efeitos dos fármacos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Oócitos/citologia , Oócitos/efeitos dos fármacos , Técnicas de Patch-Clamp , Plasmídeos , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , Proteína Quinase C beta , Proteína Quinase C-alfa/genética , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Canais de Potássio Shal/genética , Transdução de Sinais/efeitos dos fármacos , Especificidade por Substrato , Acetato de Tetradecanoilforbol/farmacologia , Transfecção , Xenopus
9.
Tissue Antigens ; 75(3): 235-41, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20070602

RESUMO

The T-cell immunoglobulin mucin (TIM) gene family encodes receptors on T-cells that regulate Th1- and Th2-cell-mediated immunity. Recently published data implied differential expression of human TIM molecules by mononuclear cells in cerebrospinal fluid of patients with multiple sclerosis (MS) and might therefore be involved in different phases of the pathogenesis of MS. The purpose of this study was to investigate the association of TIM1 gene polymorphism with susceptibility to and clinical progression in MS. In total, 272 patients with MS and 272 sex- and age-matched healthy blood donors from Western Austria were genotyped for 10 single nucleotide polymorphisms (SNPs). Five SNPs were located in the promoter region of TIM1 (rs7702920, rs41297577, rs41297579, rs9313422 and rs34333511). Another five SNPs were selected in exon 4 (rs1553316 and rs12522248) and in the intronic regions 4 and 7 of TIM1 (rs1553318, rs2279804 and rs2277025), respectively. None of these SNPs showed a significant association with MS after correction for multiple comparisons. Haplotype analysis of our data resulted in 11 haplotypes and showed no significant differences between MS patients and controls. Our findings suggest that even fine mapping of TIM1 shows no significant association of this gene with multiple sclerosis.


Assuntos
Imunoglobulinas/genética , Mucina-1/genética , Esclerose Múltipla/genética , Receptores de Superfície Celular/genética , Áustria , Éxons , Genótipo , Haplótipos , Humanos , Imunoglobulinas/metabolismo , Mucina-1/metabolismo , Esclerose Múltipla/metabolismo , Polimorfismo Genético , Polimorfismo de Nucleotídeo Único , Receptores de Superfície Celular/metabolismo , Linfócitos T/metabolismo
10.
Euro Surveill ; 13(49)2008 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-19081002

RESUMO

In recent years, Clostridium difficile infection (CDI) has emerged as an increasing problem, both in in- and outpatients. In a rural region of southern Germany, the annual number of C. difficile toxin (Tcd)-positive patients has increased from 95 to 796 in the period from 2000 to 2007. Simultaneously, the proportion of positive tests among all Tcd examinations has risen from 7.0% to 12.8%, indicating that the higher number of affected patients was not solely due to an increase in the number of assays. Elevated numbers of CDI have recently been associated with outbreaks of the ribotype 027 strain, particularly in North America. This strain has also been isolated in Europe, including in Germany. Ribotyping and PCR testing for binary toxin genes of C. difficile strains isolated from in- and outpatients demonstrate a predominance (59%) of C. difficile ribotype 001, which exhibits antibiotic resistance to erythromycin, ciprofloxacin, and moxifloxacin, but lacks binary toxin genes. In summary, in our region of Germany, the number of patients affected by CDI has increased, probably due to spread of C. difficile ribotype 001.


Assuntos
Clostridioides difficile/genética , Clostridioides difficile/isolamento & purificação , Surtos de Doenças/estatística & dados numéricos , Enterocolite Pseudomembranosa/epidemiologia , Enterocolite Pseudomembranosa/microbiologia , Vigilância da População , Medição de Risco/métodos , Clostridioides difficile/classificação , Alemanha/epidemiologia , Humanos , Incidência , Reação em Cadeia da Polimerase/estatística & dados numéricos , Prevalência , Ribotipagem/estatística & dados numéricos , Fatores de Risco
11.
Br J Pharmacol ; 154(8): 1680-90, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18516069

RESUMO

BACKGROUND AND PURPOSE: Two-pore-domain potassium (K2P) channels mediate potassium background (or 'leak') currents, controlling excitability by stabilizing membrane potential below firing threshold and expediting repolarization. Inhibition of K2P currents permits membrane potential depolarization and excitation. As expected for key regulators of excitability, leak channels are under tight control from a plethora of stimuli. Recently, signalling via protein tyrosine kinases (TKs) has been implicated in ion channel modulation. The objective of this study was to investigate TK regulation of K2P channels. EXPERIMENTAL APPROACH: The two-electrode voltage clamp technique was used to record K2P currents in Xenopus oocytes. In addition, K2P channels were studied in Chinese hamster ovary (CHO) cells using the whole-cell patch clamp technique. KEY RESULTS: Here, we report inhibition of human K2P3.1 (TASK-1) currents by the TK antagonist, genistein, in Xenopus oocytes (IC50=10.7 microM) and in CHO cells (IC50=12.3 microM). The underlying molecular mechanism was studied in detail. hK2P3.1 was not affected by genistin, an inactive analogue of genistein. Perorthovanadate, an inhibitor of tyrosine phosphatase activity, reduced the inhibitory effect of genistein. Current reduction was voltage independent and did not require channel protonation at position H98 or phosphorylation at the single TK phosphorylation site, Y323. Among functional hK2P family members, genistein also reduced K2P6.1 (TWIK-2), K2P9.1 (TASK-3) and K2P13.1 (THIK-1) currents, respectively. CONCLUSIONS AND IMPLICATIONS: Modulation of K2P channels by the TK inhibitor, genistein, represents a novel molecular mechanism to alter background K+ currents.


Assuntos
Genisteína/farmacologia , Proteínas do Tecido Nervoso/antagonistas & inibidores , Canais de Potássio de Domínios Poros em Tandem/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Animais , Células CHO , Linhagem Celular , Cricetinae , Cricetulus , Eletrofisiologia , Genisteína/administração & dosagem , Humanos , Concentração Inibidora 50 , Proteínas do Tecido Nervoso/metabolismo , Oócitos , Técnicas de Patch-Clamp , Fosforilação , Canais de Potássio de Domínios Poros em Tandem/efeitos dos fármacos , Canais de Potássio de Domínios Poros em Tandem/metabolismo , Inibidores de Proteínas Quinases/administração & dosagem , Transdução de Sinais , Xenopus laevis
12.
Phys Rev Lett ; 100(3): 032001, 2008 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-18232967

RESUMO

We present the first results for neutral-kaon mixing using (2+1)-flavors of domain-wall fermions. A new approach is used to extrapolate to the physical up and down quark masses from our numerical studies with pion masses in the range 240-420 MeV; only SU(2)_{L}xSU(2)_{R} chiral symmetry is assumed and the kaon is not assumed to be light. Our main result is B_{K};{MS[over ]}(2 GeV)=0.524(10)(28) where the first error is statistical and the second incorporates estimates for all systematic errors.

13.
Laryngorhinootologie ; 86(6): 443-7, 2007 Jun.
Artigo em Alemão | MEDLINE | ID: mdl-17219336

RESUMO

PATIENT: A clinical case of a 49-year-old man is described who presented with a right facial paresis for 4 weeks. The patient had undergone a decompression of facial nerve and a radical mastoidectomy elsewhere in 1998 because of a facial paresis and acute mastoiditis. In the following years a complete right facial paresis occurred several times improving with prednisolone. In addition to topognostic examinations a high resolution computed tomography of the temporal bone was made. CT showed a mass in the right tympanic cavity with close contact to the ossicular chain. Diagnostic tympanotomy disclosed a tumor of the tympanic segment of the facial nerve. Pathological examination indicated a diagnosis of neurinoma with an Antoni B architecture. In a second operation the tumor was resected totally and a facial nerve reconstruction was performed by a greater auricular nerve interposition graft. Seven month postoperative beginning nerve reinnervation was seen proceeding continually until the control examination after 1 1/2 year. DISCUSSION: Facial neurinoma are a rare course of facial paresis. There are no specific symptoms. That's why the diagnosis is difficult. But it is necessary to think of with differential diagnosis of facial paresis.


Assuntos
Neoplasias dos Nervos Cranianos/cirurgia , Neoplasias da Orelha/cirurgia , Orelha Média/cirurgia , Doenças do Nervo Facial/cirurgia , Paralisia Facial/etiologia , Neurilemoma/cirurgia , Neoplasias dos Nervos Cranianos/diagnóstico , Neoplasias da Orelha/diagnóstico , Orelha Média/patologia , Doenças do Nervo Facial/diagnóstico , Paralisia Facial/cirurgia , Seguimentos , Humanos , Masculino , Mastoidite/cirurgia , Pessoa de Meia-Idade , Síndromes de Compressão Nervosa/cirurgia , Regeneração Nervosa/fisiologia , Transferência de Nervo , Neurilemoma/diagnóstico , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Recidiva , Reoperação , Tomografia Computadorizada por Raios X
14.
Herzschrittmacherther Elektrophysiol ; 16(4): 229-38, 2005 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-16362729

RESUMO

The last decade has seen rapid progress in our understanding of the molecular basis of arrhythmias, particularly concerning hereditary arrhythmia syndromes. This has led to significant improvement regarding differentiation, risk stratification and therapy in these patients and their families. However, there is mounting evidence that the knowledge obtained by studying these rare monogenic disorders will also enable us to dissect the molecular mechanisms underlying polygenetic and multi-factorial arrhythmias that are by far more common in clinical practice. The goal of this review is to give a brief overview of current knowledge on the molecular basis of primary electrical heart diseases. A focus is on the long QT syndrome.


Assuntos
Potenciais de Ação , Arritmias Cardíacas/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Modelos Cardiovasculares , Canais de Potássio/metabolismo , Animais , Humanos , Biologia Molecular/métodos
15.
Arch Environ Contam Toxicol ; 41(2): 221-31, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11462147

RESUMO

A range of organohalogen compounds (10 polychlorinated biphenyl [PCB] congeners, DDT and metabolites, chlordane-related compounds, the potential natural organochlorine compound Q1, toxaphene, hexachlorobenzene, hexachlorocyclohexanes, dieldrin, and several yet unidentified brominated compounds) were detected in the blubber of four bottlenose dolphins (Tursiops truncatus), one common dolphin (Delphinus delphis), and seven dugongs (Dugong dugon), as well as in adipose tissue of a green turtle (Chelonia mydas) and a python (Morelia spilota) from northeast Queensland (Australia). The green turtle and dugongs accumulated lower organohalogen levels than the dolphins. Lower levels in dugongs were expected because this species is exclusively herbivorous. Highest PCB and DDT levels recorded in dugongs were 209 and 173 microg/kg lipids, respectively. Levels of the nonanthropogenic heptachlorinated compound Q1 (highest level in dugongs was 160 microg/kg lipids) were estimated using the ECD response factor of trans-nonachlor. Highest organohalogen levels were found in blubber of dolphins for sumDDT (575--52,500 microg/kg) and PCBs (600--25,500 microg/kg lipids). Furthermore, Q1 was a major organohalogen detected in all samples analyzed, ranging from 450--9,100 microg/kg lipids. The highest concentration of Q1 determined in this study represents the highest concentration reported to date in an environmental sample. Levels of chlordane-related compounds were also high (280--7,700 microg/kg, mainly derived from trans-nonachlor), but concentrations of hexachlorobenzene, hexachlorocyclohexanes, dieldrin, and toxaphene were relatively low and contributed little to the overall organohalogen contamination. Furthermore, a series of three major (BC-1, BC-2, and BC-3) and six minor (BC-4 through BC-9) unknown brominated compounds were observable by extracting m/z 79 and m/z 81 from the GC/ECNI-MS full scan run. Structural proposals were made for the two major recalcitrant compounds (referred to as BC-1 and BC-2). BC-2 appears to be a tetrabromo-methoxy-diphenylether (512 u) and BC-1 has 14 u (corresponding with an additional CH(2) group) more relative to BC-1. In general, the organohalogen pattern observed in blubber of dolphins was different compared to similar samples from other locations in the world, which is apparent from the fact that the four major abundant signals in the GC/ECD chromatogram of D. delphis originated from the four unknown compounds Q1, BC-1, BC-2, and BC-3.


Assuntos
DDT/análise , Golfinhos , Dugong , Poluentes Ambientais/análise , Bifenilos Policlorados/análise , Tecido Adiposo/química , Animais , Boidae , Cromatografia Gasosa , DDT/farmacocinética , Exposição Ambiental , Poluentes Ambientais/farmacocinética , Halogênios/análise , Halogênios/farmacocinética , Compostos Orgânicos/análise , Compostos Orgânicos/farmacocinética , Bifenilos Policlorados/farmacocinética , Distribuição Tecidual
16.
Chirurg ; 72(3): 305-7, 2001 Mar.
Artigo em Alemão | MEDLINE | ID: mdl-11317452

RESUMO

We present the case of a 71-year-old woman who was hospitalized because of a severe hip contusion. She had no symptoms or clinical signs of abdominal disease. Routine blood testing showed anemia, presumably owing to occult bleeding. Ultrasonographic abdominal screening revealed ileo-ileal intussusception with a central hyperechoic tumor suggestive of a lipoma as lead point. This diagnosis was confirmed at surgery, where a small bowel resection was performed. Histologic examination disclosed a benign angiolipoma of the ileum with a superficial shallow ulceration which obviously was the source of the occult blood loss. Diagnostic and therapeutic procedures and a literature review are discussed.


Assuntos
Angiolipoma/cirurgia , Doenças do Íleo/cirurgia , Neoplasias do Íleo/cirurgia , Intussuscepção/cirurgia , Idoso , Angiolipoma/diagnóstico , Angiolipoma/patologia , Diagnóstico Diferencial , Feminino , Humanos , Doenças do Íleo/diagnóstico , Doenças do Íleo/patologia , Neoplasias do Íleo/diagnóstico , Neoplasias do Íleo/patologia , Íleo/patologia , Íleo/cirurgia , Aumento da Imagem , Intussuscepção/diagnóstico , Intussuscepção/patologia , Sangue Oculto , Tomografia Computadorizada por Raios X , Ultrassonografia
17.
J Agric Food Chem ; 49(2): 759-65, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11262025

RESUMO

A Cl(7) component of technical toxaphene (CTT), previously detected in marine mammals and fish and referred to as "7-1", was isolated from contaminated estuarine sediment using preparative solid-liquid chromatography followed by reversed-phase HPLC. The structure of this compound, elucidated by GC/MS and (1)H NMR, was 2-endo,3-exo,5-endo,6-exo,8,8,10-heptachlorobornane (hereafter referred to as B7-1000). This newly identified CTT eluted in the nonpolar fraction from silica and shares the alternating endo-exo chlorine substitution pattern with other relatively nonpolar, persistent congeners (e.g., B8-1413 and B9-1679). Based on ECNI-MS response, levels of B7-1000 in tissue samples of various higher organisms including humans were as high as 16% of B8-1413. Enantioselective determination of B7-1000 using a modified cyclodextrin chiral stationary phase (beta-BSCD) resulted in enantiomer ratios that were depleted in adipose tissue of a marine bird (skua) and Weddell seal blubber (0.3 and 0.5, respectively), but not in elephant seal blubber (1.1). Elucidation of the structure of B7-1000 thus validates previous predictions of persistence based on structure-activity relationships, chromatographic properties, and molecular modeling.


Assuntos
Canfanos/química , Inseticidas/química , Toxafeno/química , Animais , Canfanos/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Peixes , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Espectroscopia de Ressonância Magnética , Mamíferos , Modelos Moleculares , Sensibilidade e Especificidade
18.
Drug Metab Dispos ; 28(2): 180-5, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10640516

RESUMO

The tobacco-specific nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) induces primarily lung tumors, which are assumed to derive from malignant transformation of alveolar type II (AII) cells within the lung. To elicit its carcinogenic effects, NNK requires metabolic activation by cytochrome P-450 (CYP)-mediated alpha-hydroxylation. Therefore, in this study the metabolism of NNK and expression of the NNK-activating CYP isoform CYP2B1 were investigated in primary cultures of rat AII cells. Although basal expression of CYP2B1 decreased in a time-dependent manner during culture of AII cells, substantial CYP2B1 protein expression was observed in AII cell cultures after the first 24 h. When AII cells were incubated with 0. 05 microM [5-(3)H]NNK, N-oxidation of NNK, which is thought to represent a detoxification pathway, was predominant (42%). alpha-Hydroxylated metabolites resulting from metabolic activation of NNK amounted to 35% of all detected metabolites. However, the proportion of alpha-hydroxylated metabolites decreased to 17% of all detected metabolites when AII cells were incubated with a 100-fold higher concentration of NNK (5 microM). In summary, this study indicates a remarkable activity of cultured AII cells to metabolize NNK, leading to substantial metabolic activation of NNK, which was more pronounced in incubations at low NNK concentration. Because exposure to NNK via cigarette smoking is thought to lead to very low plasma NNK concentrations (1-15 pM), these data suggest that metabolic activation of NNK in cigarette smokers might occur to a larger extent than would be expected according to previous metabolic studies performed with high (micromolar) NNK concentrations.


Assuntos
Carcinógenos/metabolismo , Nitrosaminas/metabolismo , Alvéolos Pulmonares/metabolismo , Animais , Northern Blotting , Western Blotting , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Citocromo P-450 CYP2B1/biossíntese , Citocromo P-450 CYP2B1/metabolismo , Hidroxilação , Técnicas In Vitro , Pulmão/metabolismo , Masculino , Oxirredução , Alvéolos Pulmonares/enzimologia , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar
19.
Pharmacoeconomics ; 14(3): 299-312, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10186468

RESUMO

OBJECTIVE: This study prospectively assesses the medical costs of Parkinson's disease (PD). DESIGN: Over a period of 3 months (from July to September 1995), patients with PD documented all items of healthcare provision. These data were then used to calculate medical costs for an individual patient as well as the costs of PD. PATIENTS AND SETTING: We included 20 outpatients with idiopathic PD from the neurological outpatient clinic, Klinikum Grosshadern, Munich, and 20 patients from two office-based neurologists in South-West Germany. MAIN RESULTS: The mean 3-month medical cost of PD in 1995 deutschmarks (DM) was 5210 ($US3390, 2240 Pounds) consisting of DM1410 ($US920, 610 Pounds) for care and nursing, DM1580 ($US1030, 680 Pounds) for drug therapy, DM1320 ($US860, 570 Pounds) for inpatient hospital care, DM40 ($US26, 17 Pounds) for outpatient care and DM860 for other expenses ($US560, 370 Pounds). The expenditure was related to the disease evolution. Patients complaining of one-sided symptoms [Hoehn and Yahr stage I; (HY I)] were less expensive to treat (DM1930, $US1250, 830 Pounds) than patients who were severely incapacitated (HY V) [DM9740, $US6330, 4200 Pounds; HY V]. After 3 to 5 years of levodopa treatment approximately 50% of patients start to experience fluctuations in motor ability and dyskinesias [Unified Parkinson's disease rating scale, part IV (UPDRS IV)]. This onset of motor complications parallels an increase in costs. For patients who experienced motor fluctuations, annual costs were DM6550 ($US4260, 2820 Pounds) compared with DM3030 ($US1960, 1300 Pounds) for patients lacking this problem. Indirect non-medical costs were not calculated due to the limited number of patients. The impact of the disease on work, however, is clearly apparent from the patients' history: 19 out of 34 patients who had already stopped working attributed this to the disease, and only 6 patients were still working at the time of the survey. CONCLUSION: PD poses a major financial impact to society which is expected to increase in future years as the age distribution shifts to older age groups. On the basis of a prevalence of PD of 183 per 100,000, we calculated an annual expenditure of DM3.0 billion for the direct medical costs of PD in Germany.


Assuntos
Doença de Parkinson/economia , Adulto , Idoso , Feminino , Custos de Cuidados de Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/terapia , Estudos Prospectivos
20.
Toxicol Appl Pharmacol ; 144(1): 163-70, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9169080

RESUMO

Tissue concentrations of mercury were determined by cold vapor atomic absorption spectrometry in different inbred mouse strains after continuous treatment with HgCl2 (3 weekly sc injections of 0.5 mg/kg bw) for up to 12 weeks. Except for the thymus, in which steadily increasing mercury concentrations were found, in steady state levels of mercury were reached in blood and liver after 4 weeks and in spleen and kidney after 8 weeks. In the closely related strains C57BL/6, B10.D2, and B10.S, which differ only or primarily at the major histocompatibility complex, mercury concentrations in blood and liver were about twofold lower and renal concentrations were about three- to fivefold lower than those detected in strains A.SW and DBA/2. Another strain difference was observed in the spleen: after 8 and 12 weeks of continuous HgCl2 treatment, mercury concentrations in the spleen of strains A.SW, C57BL/6, and B10.S were significantly higher than those in strains DBA/2 and B10.D2. The strain difference in the spleen, an organ of the immune system, correlates with the susceptibility to the HgCl2-induced systemic autoimmune syndrome in mice in that the strains showing a higher mercury accumulation in the spleen are susceptible to this form of chemically induced autoimmunity, whereas the strains with lower mercury concentrations in the spleen are resistant.


Assuntos
Cloreto de Mercúrio/administração & dosagem , Mercúrio/farmacocinética , Animais , Rim/química , Fígado/química , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Especificidade da Espécie , Baço/química , Timo/química , Distribuição Tecidual
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