Wdpcp, a PCP protein required for ciliogenesis, regulates directional cell migration and cell polarity by direct modulation of the actin cytoskeleton

Planar cell polarity (PCP) regulates cell alignment required for collective cell movement during embryonic development. This requires PCP/PCP effector proteins, some of which also play essential roles in ciliogenesis, highlighting the long-standing question of the role of the cilium in PCP. Wdpcp, a PCP effector, was recently shown to regulate both ciliogenesis and collective cell movement, but the underlying mechanism is unknown. Here we show Wdpcp can regulate PCP by direct modulation of the actin cytoskeleton. These studies were made possible by recovery of a Wdpcp mutant mouse model. Wdpcp-deficient mice exhibit phenotypes reminiscent of Bardet-Biedl/Meckel-Gruber ciliopathy syndromes, including cardiac outflow tract and cochlea defects associated with PCP perturbation. We observed Wdpcp is localized to the transition zone, and in Wdpcp-deficient cells, Sept2, Nphp1, and Mks1 were lost from the transition zone, indicating Wdpcp is required for recruitment of proteins essential for ciliogenesis. Wdpcp is also found in the cytoplasm, where it is localized in the actin cytoskeleton and in focal adhesions. Wdpcp interacts with Sept2 and is colocalized with Sept2 in actin filaments, but in Wdpcp-deficient cells, Sept2 was lost from the actin cytoskeleton, suggesting Wdpcp is required for Sept2 recruitment to actin filaments. Significantly, organization of the actin filaments and focal contacts were markedly changed in Wdpcp-deficient cells. This was associated with decreased membrane ruffling, failure to establish cell polarity, and loss of directional cell migration. These results suggest the PCP defects in Wdpcp mutants are not caused by loss of cilia, but by direct disruption of the actin cytoskeleton. Consistent with this, Wdpcp mutant cochlea has normal kinocilia and yet exhibits PCP defects. Together, these findings provide the first evidence, to our knowledge, that a PCP component required for ciliogenesis can directly modulate the actin cytoskeleton to regulate cell polarity and directional cell migration.

[Stent graft of the thoracic aorta]

Considering the demographic changes in our society and the proliferation of imaging-based improved diagnostics, both acute and chronic aortic diseases attract increasing attention and require dedicated care. Cardiac as well as vascular surgery used to represent the gold standards for therapeutic management of pathologies of the ascending aorta and the arch; however, the technological evolution of endoluminal strategies has had a serious impact on the treatment of the descending aorta, the aortic arch in combination with vascular debranching or bypass, and in selected cases even on managing pathologies of the ascending aorta. Although several case series and meta-analyses of published observations hint towards superiority of endografting in comparison to open surgical repair, the affected usually multimorbid patients with highly complex aortic disease should be subjected to an individual evaluation by a team of cardiologists, cardiac and vascular surgeons as well as imaging specialists; a dedicated individualized treatment concept in highly experienced centers of excellence is likely to provide the best results for such challenging patients.

Enhanced mobilization of the bone marrow-derived circulating progenitor cells by intracoronary freshly isolated bone marrow cells transplantation in patients with acute myocardial infarction

Autologous bone marrow cell transplantation (BMCs-Tx) is a promising novel option for treatment of cardiovascular disease. We analysed in a randomized controlled study the influence of the intracoronary autologous freshly isolated BMCs-Tx on the mobilization of bone marrow–derived circulating progenitor cells (BM-CPCs) in patients with acute myocardial infarction (AMI). Sixty-two patients with AMI were randomized to either freshly isolated BMCs-Tx or to a control group without cell therapy. Peripheral blood (PB) concentrations of CD34/45⁺- and CD133/45⁺-circulating progenitor cells were measured by flow cytometry in 42 AMI patients with cell therapy as well as in 20 AMI patients without cell therapy as a control group on days 1, 3, 5, 7, 8 and 3, 6 as well as 12 months after AMI. Global ejection fraction (EF) and the size of infarct area were determined by left ventriculography. We observed in patients with freshly isolated BMCs-Tx at 3 and 12 months follow up a significant reduction of infarct size and increase of global EF as well as infarct wall movement velocity. The mobilization of CD34/45⁺ and CD133/45⁺ BM-CPCs significantly increased with a peak on day 7 as compared to baseline after AMI in both groups (CD34/45⁺: P < 0.001, CD133/45⁺: P < 0.001). Moreover, this significant mobilization of BM-CPCs existed 3, 6 and 12 months after cell therapy compared to day 1 after AMI. In control group, there were no significant differences of CD34/45⁺ and CD133/45⁺ BM-CPCs mobilization between day 1 and 3, 6 and 12 months after AMI. Intracoronary transplantation of autologous freshly isolated BMCs by use of point of care system in patients with AMI may enhance and prolong the mobilization of CD34/45⁺ and CD133/45⁺ BM-CPCs in PB and this might increase the regenerative potency after AMI.

Surface and intracardiac ECG for discriminating conduction disorders after CoreValve implantation

Background

Transcatheter aortic valve implantation (TAVI) has been developed to minimize operative morbidity and mortality in high-risk symptomatic patients unfit for open surgery. With the proximity of the aortic valve annulus to the conduction system there is, however, an unknown risk of conduction disturbances necessitating monitoring and often cardiac pacing.

Materials and methods

We enrolled 50 consecutive patients from January 2007 to 2008 in our prospective evaluation of conduction disturbances measured by surface and intracardiac ECG recordings. Baseline parameters, procedural characteristics as well as twelve-lead surface ECG and intracardiac conduction times were revealed pre-interventionally, after TAVI and at 7-day follow-up.

Results

TAVI was performed successfully in all patients. During 7 days of follow-up the rate for first-degree AV block raised from 14% at baseline to 44% at day 7 (p < 0.001), while rates for type II second- and third-degree were 0 versus 8% (p < 0.001) and 0 versus 12% (p < 0.001), respectively. Similarly, the prevalence of new left bundle branch block (LBBB) rose from 2 to 54% (p < 0.001). Intracardiac measurements revealed a prolongation of both AH and HV interval from 123.7 ± 41.6 to 136.6 ± 40.5 ms (p < 0.001) and from 54.8 ± 11.7 to 71.4 ± 20.0 ms (p < 0.001), respectively. Pacemaker implantation at a mean follow-up of 4.8 ± 1.2 days was subsequently performed in 23 patients (46%) due to complete AV block (12%) and type II second-degree AV block (8%) while another 13 patients (26%) received a pacemaker for the combination of new LBBB with marked HV prolongation. The high rate of first-degree AV block was primarily driven by an increase in HV interval.

Conclusion

Cardiac conduction disturbances were common in the early experience with CoreValve implantation necessitating close surveillance for at least 1 week.

Ventricular tachycardia and sudden death after primary PCI-reperfusion therapy: impact on primary prevention of sudden cardiac death

BACKGROUND

Current approaches to coronary artery disease (CAD) and acute myocardial infarction (MI) may not be well represented in most primary prevention trials of sudden cardiac death (SCD).

METHODS

The contemporary and ongoing registry of the Rostock infarction network (Drip & Ship) represents a well-defined cohort of patients subjected to percutaneous coronary intervention (PCI) for ST-elevation infarction (STEMI) and served as the database for both candidates for an ICD for primary prevention of SCD and for sudden death (SCD) or ventricular tachycardia (VT) during follow-up.

RESULTS

A total of 855 consecutive patients were treated with PCI for STEMI or NSTEMI in the region of Rostock (Germany) between 2001 and 2004. While all cause mortality was still 17.2%, the SCD rate was low at 1.3% during 728 ± 366 days of follow-up. Within that time 85 patients (9.9%) developed an indication for ICD therapy due to an impaired LV function (LVEF ≤ 35%) and heart failure. Univariate predictors of an ICD indication were delayed reperfusion (p = 0.001), a high creatine kinase (CK) max (p = 0.009), a persistent wide QRS complex (p = 0.001), previous cerebrovascular events (p = 0.033), and chronic renal failure (p = 0. 001). However, only 16.5% of these patients qualifying for an ICD actually received an ICD; nevertheless, the actual SCD rate was only 3.5%, while 5.4% (46 patients) suffered VTs or ventricular fibrillation (VF). The SCD/VT rate in the entire infarct population was associated with time to reperfusion (0.032), left bundle-branch block (0.002), a longer history of CAD (0.032), and VT during follow-up.

CONCLUSION

While mortality in patients with STEMI is still alarming even with PCI, the risk of SCD may be considerably decreased even in patients with an LVEF below 35%. With the current approach to primary prevention of sudden cardiac death, approximately 10% of postinfarction patients qualify for ICD therapy; however this may only reach a quarter of patients prone to SCD.

Endogenous angiogenesis inhibitor blocks tumor growth via direct and indirect effects on tumor microenvironment

Tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) belongs to a small family of endogenous proteins that inhibits a group of enzymes, the matrix metalloproteinases (MMPs). TIMP-2 inhibits endothelial cell proliferation and migration in vitro and angiogenesis in vivo, through MMP-dependent and -independent mechanisms. However, little is known regarding the contribution of these mechanisms to the antitumor effects of TIMP-2. Using a retroviral delivery system, we stably overexpressed TIMP-2 and its mutant Ala+TIMP-2 (devoid of MMP inhibitory activity) in human adenocarcinoma A549 cells. Using real time PCR, and enzyme-linked immunosorbent assay (ELISA), we confirmed enhanced TIMP-2 expression and its MMP inhibitory activity by reverse zymography. In vitro, growth assays suggested that TIMP-2 and Ala+TIMP-2 did not alter basal cell proliferation rates, however, tumor cell migration and invasion were inhibited. In vivo, both TIMP-2 and Ala+TIMP-2 A549 xenografts exhibited reduced growth rate, CD31 immunostaining indicated decreased intratumoral microvascular density, and TUNEL demonstrated enhanced tumor cell apoptosis. Immunoblotting and immunohistochemical analyses of A549 xenograft tissues with either phospho-FAK (Tyr397) or phospho-AKT (Ser473) showed decreased activation in both TIMP-2 and Ala+TIMP-2 tumor cells. We conclude that TIMP-2-mediated inhibition of tumor growth occurs, at least in part, independently of MMP inhibition, and is a consequence of both direct effects of TIMP-2 on tumor cells and modulation of the tumor microenvironment.

Adsorption of a cationic dye, methylene blue, on to chitosan hydrogel beads generated by anionic surfactant gelation

Chitosan hydrogel beads (CSB) formed by sodium dodecyl sulphate (SDS) gelation were used for the removal of a cationic dye, methylene blue (MB), from aqueous solutions. The adsorption capacity of chitosan beads (CB) formed by alkali gelation was low because of charge repulsions between the chitosan (CS) and the MB. The adsorption capacity of CSB (4 g/L SDS gelation) for MB (100 mg/L) was 129.44 mg/g, and it decreased significantly with increasing SDS concentration during gelation. This decrease was a result of increased density of the CSB membrane materials. The CSB membrane materials formed with the 4 g/L SDS gelation showed the highest volumetric adsorption capacity. The MB adsorption on to CB and CSB increased with increasing values for the initial pH of solution. Data from both CB and CSB showed good fit to Sips isotherm models, and the maximum adsorption capacity of CSB (226.24 mg/g) was higher than that of CB (99.01 mg/g).

Dengue: A Clinicohaematological Profile

BACKGROUND

Fifty cases of fever, clinically suspected to be dengue were studied.

METHODS

Complete clinical, haematological evaluation and IgM capture assay was done.

RESULT

54% of patients clinically suspected to have dengue were positive for IgM antibodies by enzyme-linked immunosorbent assay (ELISA). The commonest clinical feature was fever with rash (85%). Thrombocytopenia was seen in 19% of patients only. One patient died of dengue shock syndrome (DSS).

CONCLUSION

Out of the 27 cases of seropositive dengue there was one death due to dengue shock syndrome. Thrombocytopenia may not always be a feature of dengue.

A study on habits of tobacco use among medical and non-medical students of Kolkata

BACKGROUND

Age-old practice "using tobacco" is a well known major global concern as it victimizes all its lovers by a host of chronic noncommunicable diseases including cancer; all develop very slowly and silently, and can cause premature death.

OBJECTIVES

To assess the pattern of tobacco use among the medical and nonmedical college students.

MATERIALS AND METHODS

A cross-sectional descriptive study was carried out in Kolkata collecting anonymous data from 515 medical and 349 nonmedical college students of two medical and two general colleges, selected randomly.

RESULT

Overall prevalence of tobacco use (18.3% vs 43.6%) and smoking (14.9% vs 40.7%) were significantly less in medical subjects, both across the sex and years of study. Lower rate of tobacco adoption at college level, higher quitting rate, correct knowledge regarding uselessness of filter attached with cigarette, and ill-effects of tobacco consumption were observed among medical participants. More nonmedical subjects were increasingly smoking compared to medical students. Filter-tipped cigarette was the top choice, and smoking was more prevalent mode of use among the nonmedical participants, most (62.3%) of whom were mild users. Curiosity was the top influencing factor for the initiation of tobacco use and two-third users wanted to quit.

CONCLUSION

Although the mortal habits was comparatively less among medical students, the medical environment seemed to fail to curb the dreadful practice totally. Thereby it can be recommended that active behavior-changing communication is required for all sections of the society to tear out the social root of the problem instead of unimpressive vague health warnings in vogue.

Effect of the addition mode of carbon nanotubes for the production of chitosan hydrogel core-shell beads on adsorption of Congo red from aqueous solution

The adsorption performance of chitosan (CS) hydrogel beads (CSBs) generated by sodium dodecyl sulfate (SDS) gelation with multi-walled carbon nanotube (CNT) impregnation was investigated for Congo red removal as a model anionic dye. CNT-impregnated CSBs were prepared by four different strategies for dispersing CNTs: (a) in CS solution (CSBN1), (b) in SDS solution (CSBN2), (c) in CS solution containing cetyltrimethylammonium bromide (CTAB) (CSBN3), and (d) in SDS solution for gelation with CTAB-containing CS solution (CSBN4). It was observed from FE-SEM study that depending on nature of CNT dispersion, CNTs were found on the outer surface of CSBN2 and CSBN4 only. The adsorption capacity of the CSBs varied with the strategy used for CNT impregnation, and CSBN4 exhibited the highest maximum adsorption capacity (375.94 mg/g) from the Sips model. The lowest Sips maximum adsorption capacity by CSBN3 (121.07 mg/g) suggested significant blocking of binding sites of CS by CNT impregnation.

[Coronary intervention - which indications are controversial?]

Actually, the further development of surgical and interventional techniques enables the treatment of complex coronary artery disease of severely ill patients. Due to this development there is a growing spectrum of possible indications for the interventional technique. Since SYNTAX trial, the individual risk stratification and discussion of possible strategies in interdisciplinar meetings is of utmost importance again. Risk stratification should contain patients history, as well as objective findings like extent of coronary artery disease, left ventricular function, pathological stress tests and patients comorbidities. Today, controversial indications up until a short time ago were possible indications for interventional techniques like demonstrated in recent trials and registries. The most discussed controversial indications were interventions at multivessel-disease with drug-eluting stents (DES), left-main stem and chronic total occlusions.

[Use of diuretics in acute decompensated heart failure]

Patients with acute heart failure usually present with dyspnoe and edema secondary to elevated intracardiac filling pressure resulting from volume overload. Despite significant progress in understanding heart failure, the treatment strategy for acute heart failure did not change in the same way. Diuretics, especially loop diuretics, are the most common therapy used in this setting. Intravenous diuretics act acutely by exerting a modest vasodilatory response and chronically by reducing circulating blood volume. Despite near universal use of diuretics in patients hospitalized with acute heart failure, nearly half of these patients are discharged from hospital without weight loss. This could be due to inadequate diuresis, overdiuresis with subsequent volume replacement and diuretic resistance. Aggressive diuresis carries a significant risk of electrolyte and volume depletion with subsequent arrythmias, hypotension, and worsening renal function. Actually there were scant data available from randomized clinical trials to guide therapeutic choice with diuretics. Thus, the choice and dosing of diuretic therapy must be individualized based on general knowledge of potency and pharmacokinetic and pharmacodynamic considerations.

A new type of chitosan hydrogel sorbent generated by anionic surfactant gelation

A new type of chitosan hydrogel beads (CSB) with a core-shell membrane structure was generated by sodium dodecyl sulfate (SDS) gelation process. CSB exhibited higher mechanical strength and acid stability than chitosan hydrogel beads (CB) formed by alkali gelation. The effect of SDS concentration variation during gelation on the adsorption capacity of CSB for congo red (CR) as a model anionic dye showed that CSB formed by 4gl(-1) SDS gelation had the highest adsorption capacity. The maximum adsorption capacity of CSB (208.3mgg(-1)) obtained from the Sips model was found slightly higher than that of CB (200.0mgg(-1)). Membrane materials of CSB obtained after squeezing core water from the beads showed approximately 25 times higher volumetric adsorption capacity than CB.

Comparative assessment of topical steroids, topical tretenoin (0.05%) and dithranol paste in alopecia areata

BACKGROUND

There have been various controversial reports regarding the efficacy of topical agents in topical therapy of alopecia areata.

AIM

The study aims to find out the effective ones among the readily available ones for a dermatologist.

MATERIALS AND METHODS

Eighty patients were chosen from the skin OPD of Bankura Sammilani Medical College, Bankura, West Bengal, after evaluating the exclusion criterions. Treatments were continued for 3 month period and a follow up after further 3 months. After dividing them into four groups-group-I (topical steroids), group-II (topical tretinoin 0.05%) group-III (dithranol paste 0.25%), and group-IV (white soft petrolatum jelly)-patients were evaluated.

RESULTS

Seventy percent of group-I, 55% of group-II, 35% of group-III, and 20% of the control group (white soft petrolatum jelly) responded favorably. Side effects in the form of dermatitis and hyperpigmentation were seen in group-III. However, no patient discontinued from the study.

CONCLUSION

We conclude that both topical steroids and tretinoin were fairly effective in limited variant of alopecia areata.

[Diagnosis and medical treatment of pulmonary arterial hypertension]

The idiopathic pulmonal arterial hypertension is characterized by a chronic proliferative conversion of the pulmonary arterial vessels leading to an increase of pulmonary vascular resistance and thus resulting in right heart failure and increase mortality rate. With growing advances in understanding of the underlying pathophysiological mechanisms and the development of modern medical treatment strategies, there is a significant improvement of the overall survival rate and quality-of life. In this review we will give an overview about the current knowledge of etiology, diagnosis and management of idiopathic pulmonal arterial hypertension.