Autofluorescence-Free Live-Cell Imaging Using Terbium Nanoparticles.

Fluorescent nanoparticles (NPs) have become irreplaceable tools for advanced cellular and subcellular imaging. While very bright NPs require excitation with UV or visible light, which can create strong autofluorescence of biological components, NIR-excitable NPs without autofluorescence issues exhibit much lower brightness. Here, we show the application of a new type of surface-photosensitized terbium NPs (Tb-NPs) for autofluorescence-free intracellular imaging in live HeLa cells. The combination of exceptionally high brightness, high photostability, and long photoluminecence (PL) lifetimes for highly efficient suppression of the short-lived autofluorescence allowed for time-gated PL imaging of intracellular vesicles over 72 h without toxicity and at extremely low Tb-NP concentrations down to 12 pM. Detection of highly resolved long-lifetime (ms) PL decay curves from small (∼10 µm2) areas within single cells within a few seconds emphasized the unprecedented photophysical properties of Tb-NPs for live-cell imaging that extend well beyond currently available nanometric imaging agents.

Arterial thromboembolism in a cat with transient myocardial thickening.

Feline arterial thromboembolism has been reported to be secondary to various feline cardiomyopathies; however, it has not been described in cats with transient myocardial thickening. A previously healthy, one-year-old, castrated male cat presented with acute paraparesis and congestive heart failure. Echocardiography revealed asymmetric left ventricular free wall thickening and left atrial enlargement. Antithrombotic treatment and cardiac medication resulted in reperfusion and mobility on day seven in one limb and on day 10 in the other. Different complications were managed successfully, including worsening acute kidney injury, inflammation, pleural effusion, and anemia. After three weeks, the cat was discharged and prescribed oral antithrombotic drugs (clopidogrel and rivaroxaban) and cardiac medication. Within five months, echocardiographic findings normalized, and medical treatment was gradually discontinued. To date, the cat remains healthy at 1735 days after the initial diagnosis and 1494 days after the last antithrombotic medication. To the best of our knowledge, this is the first case report on feline arterial thromboembolism combined with transient myocardial thickening, with favorable long-term survival.

Long-term follow-up after transvenous single coil embolization of patent ductus arteriosus in dogs.

BACKGROUND: Long-term follow-up studies after interventional therapy of patent ductus arteriosus (PDA) in dogs are rare. HYPOTHESIS: Transvenous PDA embolization with a single detachable coil is a highly effective method in patients with an angiographically determined PDA≤4.0 mm. ANIMALS: Twenty-eight dogs with an angiographic PDA≤4.0 mm were included. METHODS: Prospective follow-up study after PDA coil embolization. RESULTS: The median follow-up time was 792 days (range, 2-3, 248 days). The rate of complete closure demonstrated by Doppler color flow was 54% at day 3 after intervention and the final cumulative rate was 71%. The rate of complete closure was significantly different between small and moderately sized PDA over the study period (P<.0001) and finally was 100 and 50%, respectively. In 16 dogs with complete closure, no recanalization was found. Disappearance of the continuous heart murmur was found in 89% after 3 days, and this increased to a final cumulative rate of 96%. Indexed left ventricular internal diameter in diastole (LVDd-I) decreased significantly (P<.0001). In the group with moderately sized PDA, a significant difference (P=.0256) was seen in LVDd-I between patients with and without residual shunt after exclusion of patients with persistent severe mitral valve regurgitation. CONCLUSION AND CLINICAL IMPORTANCE: Long-term follow-up after single coil embolization showed complete closure in all small PDA but a residual shunt with mild hemodynamic consequences was present in half of the moderately sized PDA.

Dual chamber pacemaker implantation in dogs with atrioventricular block.

BACKGROUND: Pacemaker implantation is the treatment of choice for symptomatic bradyarrhythmias. In dogs, a single chamber system is commonly used. In human patients with high-grade 2nd- or 3rd-degree atrioventricular (AV) block, physiologic pacing is recommended, because it improves cardiac output, blood pressure, exercise tolerance, and quality of life. In dogs, this type of pacing is seldom used. HYPOTHESIS: The implantation of a dual chamber pacemaker in dogs with AV block is a feasible procedure for restoring AV synchrony. ANIMALS: Thirty-three privately owned dogs with high-grade 2nd- or 3rd-degree AV block were included. METHODS: Patient data of all dogs with AV block presented for pacemaker implantation between December 1997 and November 2004 were reviewed. RESULTS: Dual chamber pacemaker implantation with AV synchronous stimulation was successfully performed in 33/33 dogs (100%). In 9/33 (27%) major and in 12/33 (36%) minor complications were observed. Mean survival time for the patients discharged from hospital (n = 32) was 33.6 +/- 20.4 months (range, 3.9-83.5 months). CONCLUSION AND CLINICAL IMPORTANCE: Dual chamber pacing is a feasible procedure in dogs with 2nd- or 3rd-degree AV block and is not associated with a higher complication rate compared with single chamber pacemaker systems. A major advantage over ventricular demand pacemaker systems is the restoration of AV synchrony for a substantial period of time.

[Restrictive ventricular septal defect in a dwarf rabbit]. / Restriktiver Ventrikelseptumdefekt bei einem Zwergkaninchen.

A 9-week-old intact female dwarf rabbit was presented for evaluation of a heart murmur. Physical examination revealed a grade IV/VI systolic heart murmur with the maximal intensity over the right heart base. Evidence for a left-sided cardiomegaly was present on lateral and dorsoventral radiographs. An electrocardiogram was recorded in right lateral recumbency, which revealed a sinus tachycardia with a heart rate of 360 beats/minute. Echocardiography showed normal dimensions for the atria and ventricles. Two-dimensional echocardiography confirmed the presence of a perimembranous ventricular septal defect (VSD) with a diameter of 0.8 mm. Identification of the VSD was possible from a right (long and short axes) and a left parasternal window. Peak flow velocity of the systolic left to right shunt was 5.2 m/s. Additionally, a relative pulmonic stenosis (peak flow in the pulmonary artery of 1.02 m/s, pulsed-wave Doppler) was present. According to these findings, the VSD was classified as restrictive. At this time point, medical treatment was unnecessary. The re-examination after 7 weeks revealed unchanged morphological and haemodynamic findings. The VSD in this dwarf rabbit displayed both in the physical and echocardiographic examinations typical features as seen in dogs and cats as well as in one New Zealand white rabbit.

Direct conjugation of antibodies to the ZnS shell of quantum dots for FRET immunoassays with low picomolar detection limits.

Compact and functional nanoparticle-antibody conjugates are of paramount importance for the development of quantum dot (QD)-based immunoassays. Here, we present a simple strategy to directly conjugate IgG, F(ab')2, and Fab antibodies via their endogenous disulfide groups directly to the inorganic ZnS shell of compact penicillamine-coated QDs. The functionality of the conjugates was demonstrated by terbium (Tb)-to-QD FRET immunoassays against prostate specific antigen in serum samples. Detection limits of 2.5 pM (0.080 ng mL-1) were 10 and 25 times lower compared to conjugation via maleimide-terminated ligands and polymer chains, respectively. These more compact, simple, and sensitive QD-antibody conjugates will be highly advantageous for nanocrystal-based biosensing applications.

Transvenous embolization of small patent ductus arteriosus with single detachable coils in dogs.

Transvenous embolization of small patent ductus arteriosus (PDA; < or = 4 mm) with a single detachable coil was attempted in 24 dogs (median age 5.7 months, range, 2.6-65.5 months; median body weight 5.5 kg, range, 1.5-30.0 kg). Angiographic imaging of the duct and pressure measurements were made before and after embolization. The minimal ductal diameter was 2.7 +/- 0.7 mm. In all dogs, a single coil was employed regardless of residual shunting. Ten dogs (PDA minimal diameter range, 1.5-2.2 mm) received a 5-mm coil, and 14 dogs (PDA minimal diameter range, 2.9-3.6 mm) received a 8-mm coil. After coil embolization the angiographic shunt grade decreased significantly (n = 20, P < .001). Residual shunts were assessed by angiography 15 minutes after and by Doppler echocardiography 1-3 days and 3 months after the intervention. In the dogs treated with the 5-mm coils the residual shunt rate was low (0%, 10%, and 0% for angiography and Doppler echocardiography at 1-3 days and 3 months, respectively), in contrast to the dogs treated with the 8-mm coils (91%, 79%, and 67% for angiography and Doppler echocardiography at 1-3 days and 3 months, respectively). After 3 months, no residual murmur was found in dogs treated with the 5-mm coils (0/7), in contrast to murmurs in 5 of 12 (42%) dogs treated with the 8-mm coils. Despite incomplete closure in these dogs, volume loading of the left heart decreased in all dogs. Pulmonic or aortic coil embolism did not occur. Analysis of initial results shows that single detachable coil embolization is possible in all dogs with a small PDA (< or = 4 mm), but only very small PDA (< or = 2.5) could be treated effectively, and for the moderate PDA (2.6-4.0 mm) longer coils or multiple coils may be necessary to achieve complete occlusion.

Determinants of sentence comprehension in aphasic patients in sentence-picture matching tasks.

The results of two studies of sentence comprehension in aphasic patients using sentence-picture matching tests are presented. In the first study, 52 aphasic patients were tested on 10 sentence types. Analysis of the number of correct responses per sentence type showed effects of syntactic complexity and number of propositions. Factor analysis yielded first factors that accounted for two-thirds of the variance in performance to which all sentence types contributed. Clustering analysis yielded groups of patients whose performances progressively deteriorated and in which performance was more affected by sentence types that were harder for the group overall. These results were very similar to those previously obtained using an enactment task. In the second study, 17 aphasic patients were tested on the same 10 sentence types using both sentence-picture matching and enactment tasks. Correlational analyses showed that performance on the two tests was significantly correlated across both subjects and sentences. The results provide data relevant to the determinants of the complexity of a sentence in auditory comprehension.

[NT-proBNP as a diagnostic marker in dogs with dyspnea and in asymptomatic dogs with heart murmur]. / NT-proBNP in der Diagnostik bei Hunden mit Dyspnoe und asymptomatischen Hunden mit Herzgeräusch.

OBJECTIVE: The cardiac biomarker NT-proBNP indicates cardiac load in terms of myocardial wall stress. The objective of the study was to compare the results of NT-proBNP measurements in healthy dogs and dogs with dyspnea as well as asymptomatic dogs with heart murmur with the literature. MATERIAL AND METHODS: Between April 2007 and December 2007 dogs with dyspnea of non-cardiac origin (n=11), dogs with dyspnea of cardiac origin (n=18) and asymptomatic dogs with heart murmur (n=22) were included. Twelve clinically healthy dogs served as a control group. All animals underwent cardiologic examination including echocardiography and measurement of serum NT-proBNP concentration. Serum was centrifuged and frozen within 30 minutes and was stored frozen until analysis was performed. RESULTS: Median NT-proBNP concentration in healthy dogs was 240 pmol/l (range 131-546 pmol/l). Dogs with dyspnea and primary respiratory disease displayed a median NT-proBNP concentration of 876 pmol/l (range 97-2614 pmol/l). In patients with dyspnea of non-cardiac origin, there was a difference in the values of NT-proBNP of dogs with and without pulmonary hypertension diagnosed by echocardiography. Dogs with dyspnea of cardiac origin displayed a median NT-proBNP concentration of 2000 pmol/l (range 137-2614 pmol/l). Low normal NT-proBNP values were only found in patients with pericardial effusion. Median NT-proBNP concentration in asymptomatic dogs with heart murmur was 698.5 pmol/l (range 121-2614 pmol/l). Considerably increased values were particularly measured in asymptomatic patients with severe congenital heart disease. CONCLUSION AND CLINICAL RELEVANCE: NT-proBNP represents a useful additional diagnostic parameter in veterinary clinical cardiology to assess the severity of cardiac disease. Interpretation must take into consideration the clinical picture of the patient, as dogs with severe arrhythmias, sepsis and pulmonary thromboembolism may display high NT-proBNP levels without congestive heart failure. Our results indicate the following cut-off values: <500 pmol/l: no relevant cardiac load; 500-900 pmol/l: moderate cardiac load; >900 pmol/l: severe cardiac load.

Transvenous coil embolization of patent ductus arteriosus in small (≤3.0 kg) dogs.

BACKGROUND: Surgical and interventional therapy for occlusion of a patent ductus arteriosus (PDA) in small dogs is challenging. Interventional closure of a PDA is rarely described in small dogs. HYPOTHESIS: Transvenous single-coil occlusion of a PDA in small (≤3.0 kg) dogs is possible and safe. ANIMALS: Twenty-one client-owned dogs with a left-to-right shunting PDA. METHODS: Prospective clinical study. Inclusion criteria were a left-to-right shunting PDA and a body weight ≤3.0 kg. Dogs with additional congenital cardiac diseases were excluded. Without arterial access, a single detachable coil was implanted by a transvenous approach with a 4 Fr catheter. RESULTS: Twenty-one dogs were the study population with Chihuahua and Yorkshire Terrier being the commonest breeds (n = 6 and n = 5, respectively). There were 14 female and 7 male dogs. The age range was 1.9-83.5 months (median, 7.7 months), and the body weight was 1.0-2.9 kg (1.87 ± 0.45). By angiography, the minimal ductal diameter measured 1.2-2.4 mm (median, 1.8 mm) and the PDA ampulla diameter was 2.4-5.9 mm (median, 4.6 mm). Coil implantation was successful in all dogs. After detachment of the coil from the delivery cable, repositioning of the pulmonary loop of the coil became necessary in 1 dog. The prevalence of immediate closure was 76%. The prevalence of cumulative closure was 90%. CONCLUSION: For an experienced cardiologist, transvenous occlusion of a PDA in small dogs is possible with a 4 Fr catheter and a commercial single detachable coil. Arterial access is not essential. The procedure is safe and successful in experienced hands.

Pelvic inflammatory disease: a review with emphasis on antimicrobial therapy.

Pelvic inflammatory disease accounts for 5%-20% of hospital admissions for gynecologic problems and is associated with health care costs of more than 1 billion dollars annually. This article reviews the epidemiology, polymicrobial etiology, and diagnosis of this disease state. Special consideration is given to in vivo and in vitro studies of antimicrobial therapy, including both established regimens and expanded-spectrum beta-lactam antibiotics. The adjunctive modalities reviewed include treatment of sexual contacts, removal of intrauterine devices, use of alternative contraceptive methods associated with a reduced risk of disease, and surgery. Although understanding of pelvic inflammatory disease has increased markedly, investigation of its various aspects is both necessary and ongoing. In particular, well-designed, controlled, comparative clinical trials of new treatment regimens must be performed to verify a true advantage of these therapies.

PIP: This state-of-the-art review focuses on the epidemiology, etiology, diagnosis, and treatment of pelvic inflammatory disease (PID). 5-20% of hospital admissions for gynecologic problems are secondary to PID; the condition itself is associated with health care costs of about $1.25 billion each year in the US. Special consideration is given in this article to in vivo and in vitro studies of antimicrobial therapy, including both established regimens and expanded spectrum beta-lactam antibiotics. Early treatment of PID can reduce the effects of the infection on the fallopian tubes; however, microbe-related inflammation and tubal necrosis can precede the manifestation of symptoms, especially in cases where Chlamydia is the infecting agent. The 2nd-generation cephalosporins seem to offer advantages in the treatment of PID because of an expanded spectrum that includes many of the major pathogens. In vitro tests have demonstrated considerable activity against penicillinase-producing strains of N gonorrhoeae resistant to both penicillin and 1st-generation cephalosporins. Cefoxitin is currently considered the most attractive such cephalosporin and has shown cure rates of 95-100% in the treatment of uncomplicated gonorrhea. Also reviewed in this article are adjunctive methods of treatment, including treatment of sexual contacts, removal of IUDs, use of alternate methods of contraception associated with a reduced risk of disease and surgery. Oral contraceptives are the logical alternative when a switch in contraception is indicated given the lower risk of PID incidence and severity, infertility, and ectopic pregnancy in pill users. There remains a need for well-designed, prospective, comparative studies of new treatment regimens.

Location of lesions in stroke patients with deficits in syntactic processing in sentence comprehension.

Sixty patients, 46 with left-hemisphere strokes and 14 with right-hemisphere strokes, and 21 normal control subjects were tested for the ability to use syntactic structures to determine the meaning of sentences. Patients enacted thematic roles (the agent, recipient and goal of an action) in 12 examples of each of 25 sentence types, which were designed to test a wide variety of syntactic operations. Both right-and left-hemisphere damaged patients performed worse than control subjects on syntactically complex sentences, and left-hemisphere patients performed worse than right-hemisphere patients. Eighteen patients with left-hemisphere strokes underwent CT scanning to image the perisylvian association cortex. There was no difference between the performance of patients with anterior and posterior lesions, and no correlation between the degree of impairment and the size of lesions in different regions of the perisylvian cortex. These results are consistent with the view that syntactic processing involves an extensive neural system, whose most important region is the left perisylvian cortex. When these results are combined with those of other studies, the picture that emerges is one in which, within this cortical region, this system manifests features of both distributed and localized processing.

Lexical factors in the word-superiority effect.

In the Reicher-Wheeler paradigm, fluent readers can identify letters better when they appear in a word than when they appear in either a pronounceable pseudoword (a lexicality effect) or a single letter (a word-letter effect). It was predicted that if both of these effects involve a lexical factor, then adult acquired dyslexic subjects whose deficit prevents access to visual word form should show disruptions of the normal effects on the Reicher-Wheeler task. The results were that dyslexic subjects as well as matched control subjects showed a lexicality effect; however, while the control subjects showed a normal word-letter effect, the dyslexic subjects showed a reverse letter-superiority effect. Both effects, however, showed a systematic variation: As performance on lexical decision improved, the subjects' performance on words in the Reicher-Wheeler task was better than that for all the other conditions. These subject correlations were replicated by using data from a second lexical decision experiment, which utilized the same words and pseudowords that were used in the Reicher-Wheeler task. In addition, an item analysis showed that the words that the subjects had discriminated correctly in lexical decision showed a significant advantage over those that they had not, as well as an improvement relative to the other conditions. These results suggest that there is a lexical factor underlying the lexicality and word-letter effects, and it is proposed that the abnormal letter-superiority effect can be accounted for as the manifestation of other competing factors.

Pain experience during transvaginal aspiration of immature oocytes.

BACKGROUND: We wanted to determine the pain conception prior to, during, and after transvaginal recovery of immature oocytes for in vitro maturation (IVM). MATERIAL AND METHODS: Fifty women received 1 g Paracetamol and 0.125 mg Halcion as preanalgesics. During the oocyte pick-up para-cervical blockage (PCB) with 5 ml Citanest x2 was given, in addition to 1.5-2 ml Raphiphene intravenously. The pain was measured by using a visual analog scale (VAS). The expected pain was recorded just before the oocyte pick-up. Right after the oocyte pick-up the actual pain was measured and again 1/2 hour, and 1-11/2 hour later. Furthermore, the pain was recorded every second hour after discharge and every third hour the next day. RESULTS: Forty-three women experienced less pain than expected (p=0.003). The pain conception was correlated to the number of punctures through the vagina (p=0.012). Fifteen patients received analgesics postoperatively, and all patients were discharged less than 2 hours after the procedure without complaints. None noted any discomfort or pain after 30 hours following the oocyte pick-up. CONCLUSION: Although the IVM oocyte pick-up procedure involved puncture of very small follicles that required numerous punctures through the vagina, the experienced pain was significantly less than the expected pain, and the procedure was well accepted.

Isolation of a Drosophila homolog of the vertebrate homeobox gene Rx and its possible role in brain and eye development.

Vertebrate and invertebrate eye development require the activity of several evolutionarily conserved genes. Among these the Pax-6 genes play a major role in the genetic control of eye development. Mutations in Pax-6 genes affect eye development in humans, mice, and Drosophila, and misexpression of Pax-6 genes in Drosophila can induce ectopic eyes. Here we report the identification of a paired-like homeobox gene, DRx, which is also conserved from flies to vertebrates. Highly conserved domains in the Drosophila protein are the octapeptide, the identical homeodomain, the carboxyl-terminal OAR domain, and a newly identified Rx domain. DRx is expressed in the embryo in the procephalic region and in the clypeolabrum from stage 8 on and later in the brain and the central nervous system. Compared with eyeless, the DRx expression in the embryo starts earlier, similar to the pattern in vertebrates, where Rx expression precedes Pax-6 expression. Because the vertebrate Rx genes have a function during brain and eye development, it was proposed that DRx has a similar function. The DRx expression pattern argues for a conserved function at least during brain development, but we could not detect any expression in the embryonic eye primordia or in the larval eye imaginal discs. Therefore DRx could be considered as a homolog of vertebrate Rx genes. The Rx genes might be involved in brain patterning processes and specify eye fields in different phyla.