Identification of mutations in the PARK2 gene in Serbian patients with Parkinson's disease

Mutations in the PARK2 (PRKN) gene are the most common cause of autosomal-recessive (AR) juvenile parkinsonism and young-onset Parkinson's disease (YOPD). >100 different variants have been reported, including point mutations, small indels and single or multiple exon copy number variations. Mutation screening of PARK2 was performed in 225 Serbian PD patients (143 males and 82 females) with disease onset before 50 years and/or positive family history with apparent AR inheritance. All coding regions and their flanking intronic sequences were amplified and directly sequenced. Whole exon multiplications or deletions were detected using Multiple Ligation Probe Amplification (MLPA) method. We identified 12 PD patients with PARK2 mutations (5.3%). Five patients (2.2%) had biallelic mutations and seven (3.1%) were single mutation carriers. Patients with compound heterozygous mutations had earlier onset of the disease compared to non-carriers (p = 0.005) or heterozygotes (p = 0.001). Other clinical features in mutation carriers were not different compared to non-carriers. In our cohort, sequence and dosage variants were equally represented in patients, inducing their first symptoms mainly before the age of 30. For efficient genetic testing strategy, patients with early, especially juvenile onset of PD were strong candidates for both dosage and sequence variants screening of PARK2 gene.

Brain structural and functional signatures of impulsive-compulsive behaviours in Parkinson's disease

This study assessed brain structural and functional alterations in patients with Parkinson's disease and impulsive-compulsive behaviours (PD-ICB) compared with controls and PD no-ICB cases. Eighty-five PD patients (35 PD-ICB) and 50 controls were recruited. All subjects underwent three-dimensional T1-weighted, diffusion tensor (DT), and resting state functional magnetic resonance imaging (RS fMRI). We assessed cortical thickness with surface-based morphometry, subcortical volumes using FIRST, DT MRI metrics using region of interest and tractography approaches, and RS fMRI using a model free approach. Compared with controls, both PD groups showed a pattern of brain structural alterations in the basal ganglia (more evident in PD no-ICB patients), sensorimotor and associative systems. Compared with PD no-ICB, PD-ICB cases showed left precentral and superior frontal cortical thinning, and motor and extramotor white matter tract damage. Compared with controls, all patients had an increased functional connectivity within the visual network. Additionally, PD no-ICB showed increased functional connectivity of bilateral precentral and postcentral gyri within the sensorimotor network compared with controls and PD-ICB. Severity and duration of PD-ICB modulated the functional connectivity between sensorimotor, visual and cognitive networks. Relative to PD no-ICB, PD-ICB patients were characterised by a more severe involvement of frontal, meso-limbic and motor circuits. These data suggest ICB in PD as the result of a disconnection between sensorimotor, associative and cognitive networks with increasing motor impairment, psychiatric symptoms, and ICB duration. These findings may have important implications in understanding the neural substrates underlying ICB in PD.

10 GHz pulse repetition rate Er:Yb:glass laser modelocked with quantum dot semiconductor saturable absorber mirror

Semiconductor saturable absorber mirror (SESAM) modelocked high pulse repetition rate (≥10  GHz) diode-pumped solid-state lasers are proven as an enabling technology for high data rate coherent communication systems owing to their low noise and high pulse-to-pulse optical phase-coherence. Compared to quantum well, quantum dot (QD)-based SESAMs offer potential advantages to such laser systems in terms of reduced saturation fluence, broader bandwidth, and wavelength flexibility. Here, we describe the first 10 GHz pulse repetition rate QD-SESAM modelocked laser at 1.55 μm, exhibiting 2 ps pulse width from an Er-doped glass oscillator (ERGO). The 10 GHz ERGO laser is modelocked with InAs/GaAs QD-SESAM with saturation fluence as low as 9  μJ/cm².

Possible implications of TGF-alpha in oesophageal dysmotility in systemic sclerosis

OBJECTIVES

Hypoxia is a characteristic feature of systemic sclerosis (SSc).Transforming growth factor alpha (TGF-α) has an important role in excessive inflammation under hypoxic conditions. Since oesophageal dysmotility is one of the most common signs of SSc, the aim of this study was to explore the relation between TGF-α and oesophageal dysmotility in SSc.

METHODS

The study included 35 patients with SSc and 32 healthy controls matched for sex and age. Serum concentrations of TGF-α were measured using ELISA. Oesophageal motility was assessed by oesophageal scintigraphy. A multiple-swallow test was performed in the study population with 99mTc-DTPA. A region of interest over the entire oesophagus was defined and the retention index (RI) was calculated.

RESULTS

Statistically significant differences in serum concentration of TGF-α as well as of RI of 99mTc-DTPA were found between patients with SSc and healthy controls. A statistically significant correlation was found between serum concentrations of TGF-α and RIs of 99mTc-DTPA. This correlation was inverse, i.e. when serum concentrations of TGF-α increased, the RI of 99mTc-DTPA decreased (Spearman rho =-0361, p=0.033).

CONCLUSIONS

These results point to a possible relation between TGF-α and oesophageal dysmotility in SSc. Although the results do not explain the exact role of this cytokine in the pathogenesis of esophageal changes, the finding of inverse correlation between TGF-α and oesophageal dysmotility is intriguing and requires further investigation.

Systolic right ventricular adaptive changes in athletes as predictors of the maximal functional capacity: a pulsed tissue Doppler study

AIM

The aim of this study was to extend the analysis of the systolic right ventricular (RV) adaptation to combined endurance and strength training, to assess the utility of tissue Doppler imaging in detecting the degree of these changes and to find independent RV predictors of the maximal functional capacity.

METHODS

Standard Doppler and TDI were used to assess cardiac parameters at rest in 37 elite male athletes (16 wrestlers, 21 water polo players) and 20 sedentary subjects of similar age. Progressive maximal test on treadmill was used to assess VO2max. The obtained parameters were adjusted for HR, FFM, and BSA.

RESULTS

Wrestlers showed higher VO2max than controls, but lesser than water polo players. RV diameter was larger in athletes. Right atrial pressure (RVE/e) was higher in water polo players than in other groups. Systolic function assessed by tricuspid annular plane systolic excursion (TAPSE) and RVs' was the highest in wrestlers. Global RV systolic parameters myocardial performance index (MPI) and preejection time/ejection time index (PET/ET) were similar. On multivariate analysis systolic parameters were independent predictors of VO2max only in wrestlers: RVs' (beta=3.18, P=0.001) and RV ET (beta=2.32, P=0.001). RVE/e` correlated with RVs' (r=-0.57, P=0.000). TAPSE correlated with RV ET (r=0.32, P=0.015) and RVs` (beta=0.28, P=0.033).

CONCLUSION

Systolic function assessed by TAPSE and RVs` has more improved in less endurance athletes. RVs`and TDI ejection time predict VO2max in wrestlers, and possibly in other athletes with lesser right atrial pressure. TDI enables quantifying RV adaptation degree in athletes, but complementary to M-mode technique.

Function after intersphincteric resection for low rectal cancer and its influence on quality of life

AIM

The aim of the study was to investigate function and quality of life after different types of intersphincteric resection (ISR).

METHOD

Between January 2006 and February 2008, 45 patients (34 men and 11 women) with distal third rectal cancer underwent curative ISR. Function was evaluated using the Memorial Sloan Kettering Cancer Center bowel function questionnaire and Wexner score, anal manometry and measurements of rectal capacity were also performed. Quality of life was assessed using the Serbian version of the European Organisation for Research and Treatment of Cancer, quality of life questionnaire (EORTC QLQ-C30) and the translated version of the fecal incontinence quality of life scale (FIQL).

RESULTS

There were no postoperative deaths. Partial ISR was performed in 22 (48.9%) patients, subtotal ISR was performed in 19 (42.2%) patients and total ISR was performed in four (8.9%) patients. Anastomotic leakage occurred in nine (20%) patients. Five (11.1%) of 45 patients had major (complete) incontinence and a further six (13.3%) patients had continuing frequent faecal leakage 12 months after ileostomy reversal. There was no significant difference in quality of life between the groups in the EORTC QLQ-C30 scale, but this was significantly altered by internal anal sphincter resection in two of the FIQL scales (coping/behaviour and depression/self-perception).

CONCLUSION

Although ISR does not affect quality of life in general, the extent of internal anal sphincter resection has a negative impact on symptom-specific quality of life owing to faecal incontinence.

Determination of parameters of the Jacobi room model using the Brownian motion model

Parameters of the Jacobi room model were estimated with simulation of Brownian motion. Deposition on internal room surfaces and attachment of progeny atoms to three modally distributed aerosols were taken into account. The values of parameters were presented as functions of aerosol concentrations. The deposition rate of an unattached progeny was estimated in the range 30-47 h-1; the deposition rate of an attached progeny was very small and its range is 0.0007-0.004 h-1; the attachment rate of a progeny is in range 40-170 h-1. The statistical uncertainty was lower than 1%. The ranges of parameters were similar to those reported in literature.

Absorbed fractions for electrons and beta particles in sensitive regions of human respiratory tract

The absorbed fractions (AF) of electrons in sensitive layers of human respiratory tract were calculated in this paper. For that purpose the source code for simulation package PENELOPE, based on Monte Carlo method, was developed. The human respiratory tract was modeled according to ICRP66 publication, where AF of electrons was calculated using EGS4 simulation software. Some approximations used in ICRP66 were corrected in this work, and new values of AF for radon progeny are given. Minimal energy (EABS) that electron can have during transport through material is 1 keV in ICRP66, while it is set as low as 100 eV in the presented work. Lowering value of EABS gives more accurate results for AF when initial energy of electrons is below 50 keV. To represent tissue, water is used in ICRP66, while in this work epithelia tissue is used.

Endorectal ultrasound (ERUS) in pelvic disorders

Endorectal ultrasound (ERUS) imaging is a complex process using electronic devices to control ultrasound waves and produce images of anatomic structures. It is a simple, cheep and well-tolerated procedure that provides excellent images of rectal and anal canal wall and pelvic floor muscles together with surrounding organs and tissues. The direct imaging of anal canal and pelvic floor muscles with surrounding tissues allows one to identify sphincter defects, anorectal abscesses and fistulas as well as great variety of benign and malignant pathology of the pelvis. Basically, techniques for ERUS are very similar, but there are some slight modifications regarding equipment, indications, and localization of pathologic process. We describe the technique, indications, results and pitfalls of ERUS with the Bruel and Kjaer type 1850 endosonic probe with 7 and 10 MHz transducers in benign pelvic disorders.

Salvage rectal surgery--overview

Recurrence of the disease represents the major problem in patients who undergo "curative" resection for rectal cancer, with published rate ranging from 3 to 50%. Most relapses occur within first two years of follow-up. Depending on the site of the recurrence, it can be local or distant. It also can be solitary or diffuse. In terms of potential surgical cure the best results are achieved with solitary, localized metastases. The most common sites of the solitary metastases are pelvis, liver and lung, with a fairly even distribution among these three sites. Other sites of the localized metastases can be peritoneum, lymph nodes, brain, bone, abdominal wall, ureter and kidney. These sites are less common, but not so amenable to resection. Local recurrence varies depending on the original type of surgery. It can be stated that surgical technique directly influences local recurrence rate in patients with rectal cancer. According to the results from a number of different authors 5-year survival rate after reresection is 2-13% of all patients with locally recurrent cancer, both alone and associated with distant metastases. The most important moment in this problem is to decide when not to operate. The absolute contraindications for salvage surgery are: "frozen pelvis", aneuploid tumors and those with mucinous component, clinical or CT evidence of invasion of the pelvic nerves, lymphatics or veins, or ureter bilaterally. Also, evidence of involvement of the lateral pelvic sidewalls and/or upper sacral marrow, and/or S2 is an absolute contraindication for surgery. Thus, main goals of this type of surgery are respectively: palliation of symptoms, a good quality of life and, if possible, cure with low treatment-related complication rates.

Ulcerative colitis indications and timing for surgery

Surgery continues to have a major role in the management of ulcerative colitis because it may save the patient's life, eliminate the long-term risk of cancer, and most important, abolish the disease. Treatment of ulcerative colitis still remains the challenge despite growing knowledge about the disease, advances in medical treatment and surgical techniques. Indications and optimal timing for surgery are the mainstays of good outcome and are as important as the quality of medical therapy and surgery. Ulcerative colitis is a complex disease where medical and surgical treatment frequently overlap and clinical decision making should be in hands of well trained and experienced team consisting of surgeon, gastroenterologist, radiologist and pathologist. Recently developed drugs, with high potential in the treatment of severe attacks of ulcerative colitis brought some changes in therapy and indications for surgical treatment. Although as many as half of patients with inflammatory bowel disease require at least one surgical procedure to address complications derived from their disease, the decision in favor of a surgical approach and its timing is rarely an easy one.

First thousand rectal cancer cases: Local recurrence and survival

In the period 1990 - 2002, 1674 patients with colorectal carcinoma were operated in the First Surgical Clinic, Third Department for Colorectal Surgery. In 1264 cases (75,5%) rectal carcinoma was the indication for surgical treatment. Sphincter saving procedures (SSP) were performed in 824 (65,2%), abdominoperineal resections (APR) in 340 (26,9%) and resections of rectum with definitive stoma (Hartmann procedure) in 100 (7,9%) patients. We analyzed 1095 cases where curative SSP or APR were performed. All cases where curative resection was not possible because of liver metastases or inability to excise all macroscopic disease were excluded. In the group of patients where SSP was performed (767 cases), there were 26,6% high colorectal anastomoses (8cm from anal verge), 65,4% with low (4-8cm from anal verge) and 8,0% with intersphincteric coloanal anastomosis (cm from anal verge). Patohistological exam showed 5,3% Dukes A, 53,1% Dukes B, 36,5% Dukes C and 4,9% Dukes D. In the APR group (328 cases) there were 1,5% Dukes A, 32,4% Dukes B, 62,1% Dukes C and 3,5% Dukes D. In this study we analyzed local recurrence and five-year survival in both groups. Recurrence of the disease was registered in 325 (29,6%) out of 1095 patients. Local recurrence was found in 81 (7,4%) patients. In the SSP group recurrence occured in 215 (28,0%) out of 767 curative resections. Local recurrence alone was found in 53 patients (6,9%). SSP group was also divided into two subgroups; in the first group TME was performed and in second transection of mesorectum was carried out. Analyzing local recurrence in these two groups, in the TME group it was 7,6% and in the transection group 5,6%. In the APR group recurrence was registered in 110 (33,5%) out of 328 patients while local recurrence alone was found in 28 (8,5%) cases. Analyzing mortality we found that 234 (21,4%) out of 1095 patients died during follow-up. In the SSP group 154 out of 767 patients (20,1%) died. In the TME group mortality was 21,7% and in the transection group 16,9%. Mortality in the APR group showed that 80 out of 328 (24,4%) patients died during follow-up. Analysis by the Kaplan-Meier?s test shows cumulative survival of 0,69 for all cases. In the SSP group cumulative survival is 0,72 and in the APR group 0,64 with statistically significant difference (p,001). In the TME group cumulative survival is 0,75 and in the transection group 0,72 with statistically significant difference (p,05). We believe that performing SSP should be encouraged whenever it is possible because there is no difference in local recurrence rates and survival compared to APR. Transection of mesorectum can safely be performed in most cases with tumors located more than 8 cm form anal verge. We believe that exact preoperative staging and preoperative radiotherapy could improve results.

Canadian multicenter randomized clinical trial of chorion villus sampling and amniocentesis. chromosome mosaicism in CVS and amniocentesis samples

Data on 1040 chorionic villus and 969 amniotic fluid samples were collected from women studied in the Canadian Multicentre Randomized Clinical Trial of Chorion Villus Sampling and Amniocentesis. Cytogenetic results were obtained from 98.0 per cent of chorionic villus samples and from 99.9 per cent of amniotic fluid samples. Level I mosaicism (a single cell with an abnormal karyotype) occurred frequently in both chorionic villus and amniotic fluid samples and appeared to have no clinical significance. Level II mosaicism occurred in 0.9 per cent of CVS mesenchyme and 1.5 per cent of amniotic fluid cultures and in general was not perceived to be of sufficient concern to warrant cytogenetic follow-up studies. Level III mosaicism was reported in 18 CVS cases (15 cytotrophoblast, 1 mesenchyme, and 2 with both cell methods) and in one amniotic fluid case. In all cases but one (fetus with trisomy 18), level III mosaicism was confined to the placenta. Maternal cell contamination occurring with a frequency of 6.4 per cent in the mesenchyme analyses was a concern. This study supports the final report of the Canadian Multicentre Randomized Clinical Trial of Chorion Villus Sampling and Amniocentesis. Cytogenetic analysis of chorionic villus samples appears to be an acceptable alternative to the analysis of amniotic fluid samples. However, because of mosaicism and maternal cell contamination concerns, the examination of both cytotrophoblast preparations and mesenchyme cultures from chorionic villus samples is recommended.

Ecto-5'-nucleotidase. I. Expression in human normal and neoplastic lymphoid cell lines representing sequential stages of B-cell differentiation

The possible association of ecto-5'-nucleotidase (5'-NT) with differentiation of B-cells was explored with the use of normal and neoplastic lymphoblastoid cell lines representing sequential stages of B-cell maturation. There was no relationship between patterns of enzyme expression in the cell lines and immunoglobulin (Ig) secretion, chromosome constitution, proliferative rate, cell volume, or the presence of B1 and B2 antigens. Pre-B-cell lines, which were negative for surface Ig or Ig secretion but positive for cytoplasmic mu-chains, showed the presence of 5'-NT, whereas 9 of 11 lymphoma cell lines, Burkitt's or non-Burkitt's type, both secreting and nonsecreting, did not exhibit enzyme activity. Four myeloma cell lines and 13 of 15 normal B-cell lines were positive for 5'-NT. These results suggested that 5'-NT was present in pre-B-cells and in some very early B-cells. 5'-NT usually disappeared from early and some intermediate B-cells and reappeared in mature B-cells and plasmacytoid cells.