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OBJECTIVE: Encephalocele is a rare congenital neural tube defect (NTD) characterized by herniation of intracranial contents through a defect in the skull. In our study, encephalocele was diagnosed in our clinic and its association with hydrocephalus was evaluated. The effect of this association on the prognosis was discussed. PATIENTS AND METHODS: Patients who underwent surgery and follow-up with the diagnosis of encephalocele in the neurosurgery clinic of our hospital in an 8-year period from 2013 to 2021 were retrospectively examined. RESULTS: Patient records were obtained from the case notes of patients who underwent excision and repair for encephalocele. Of the 78 patients included in the study, 88.4% underwent surgery in the neonatal period. Moreover, 47% of the patients are male, and 31% are female. Encephalocele was present in 62.8% of patients and meningocele in 37.2%. Furthermore, 82.1% of encephalocele sacs were located in the occipital region. Chiari type 3 malformation was present in 57.6% of patients. Hydrocephalus developed in 56.4% of patients. There was an additional syndrome in 10.3% of the cases. The most common additional syndromes were corpus callosum dysgenesis with 39.7% and colpocephaly with 29.5%. The additional disease was present in 43.6% of patients. Preoperative and postoperative examination findings of more than half of patients were normal, but 33.3% were apathetic. Furthermore, 67.9% of patients, who underwent complete repair, survived, and 32.1% died. Hydrocephalus was present in 73.5% of patients with encephalocele (p<0.05). Hydrocephalus developed in 77.8% of patients with Chiari type 3 malformation (p<0.05). Hydrocephalus was found in 88.0% of patients with Ex (p<0.05). CONCLUSIONS: Encephalocele, which is a subgroup of NTD, differs clinically by its location and accompanying additional anomalies. In encephaloceles, the risk of morbidity and mortality can only be reduced with the multidisciplinary approach. Hydrocephalus and Chiari type 3 malformation are common in patients with encephalocele. These associations adversely affect the prognosis of the disease. Further research should be conducted on the evaluation of risk factors of NTD and methods of prevention from NTD. In this regard, we recommend that the training be repeated at certain intervals and that people's awareness should be raised. [ABSTRACT FROM AUTHOR]

The angiotensin II receptor, losartan, has been found to inhibit platelet aggregability to some extent in in vitro experiments. There have been conflicting results about the in vivo effects of losartan. We sought to clarify the in vivo effect of losartan on platelet aggregation. Forty patients with grade I essential hypertension were treated with losartan for 3 weeks. Platelet aggregation tests with adenosine diphosphate (ADP) and ristocetin were analyzed and compared before and at the end of the study. Losartan effectively decreased systolic (SBP) and diastolic (DBP) blood pressure. Mean SBP before and after treatment was 159.6 ± 12.8 and 149.2 ± 17.3 mmHg, respectively. Mean DBP decreased from 93.7 ± 8.2 to 87.7 ± 10.3 mmHg after treatment. The results of the platelet aggregation tests with ADP and ristocetin were not significantly different when both rate and amplitude of maximal aggregation were included. Peak platelet aggregation with ADP regarding the lowest light transmission in the aggregometer was 59.8% ± 24.3% before and 58.3% ± 18.1% after the treatment. The same variables with ristocetin were 66.8% ± 21.6% and 60.8% ± 23.3%, respectively. In vivo effects of losartan on platelet aggregation with ADP and ristocetin were insignificant. [ABSTRACT FROM AUTHOR]

Abstract Background Identification of approximate tandem repeats is an important task of broad significance and still remains a challenging problem of computational genomics. Often there is no single best approach to periodicity detection and a combination of different methods may improve the prediction accuracy. Discrete Fourier transform (DFT) has been extensively used to study primary periodicities in DNA sequences. Here we investigate the application of DFT method to identify and study alphoid higher order repeats. Results We used method based on DFT with mapping of symbolic into numerical sequence to identify and study alphoid higher order repeats (HOR). For HORs the power spectrum shows equidistant frequency pattern, with characteristic two-level hierarchical organization as signature of HOR. Our case study was the 16 mer HOR tandem in AC017075.8 from human chromosome 7. Very long array of equidistant peaks at multiple frequencies (more than a thousand higher harmonics) is based on fundamental frequency of 16 mer HOR. Pronounced subset of equidistant peaks is based on multiples of the fundamental HOR frequency (multiplication factor n for nmer) and higher harmonics. In general, nmer HOR-pattern contains equidistant secondary periodicity peaks, having a pronounced subset of equidistant primary periodicity peaks. This hierarchical pattern as signature for HOR detection is robust with respect to monomer insertions and deletions, random sequence insertions etc. For a monomeric alphoid sequence only primary periodicity peaks are present. The 1/fβ – noise and periodicity three pattern are missing from power spectra in alphoid regions, in accordance with expectations. Conclusion DFT provides a robust detection method for higher order periodicity. Easily recognizable HOR power spectrum is characterized by hierarchical two-level equidistant pattern: higher harmonics of the fundamental HOR-frequency (secondary periodicity) and a subset of pronounced peaks corresponding to constituent monomers (primary periodicity). The number of lower frequency peaks (secondary periodicity) below the frequency of the first primary periodicity peak reveals the size of nmer HOR, i.e., the number n of monomers contained in consensus HOR.

Purpose: To evaluate the neuroprotective effect of resveratrol, urapidil, and a combined administration of these drugs against middle cerebral artery occlusion (MCAO) induced ischemia/reperfusion (IR) injury model in rats., Methods: Thirty-five rats were divided into five groups of seven animals each. Animals in IR, IR resveratrol (IRr), IR urapidil (IRu), and IR + combination of resveratrol and urapidil (IRc) were exposed to MCAO induced cerebral ischemia reperfusion injury model. Rats in IRr and IRu groups received 30-mg/kg resveratrol and 5-mg/kg urapidil respectively. Animals in IRc received a combined treatment of both drugs. At the end of the study, brain tissues were used for oxidative stress (malondialdehyde, glutathione, and superoxide dismutase), pro-apoptotic caspase-3, anti-apoptotic Bcl-2, and pro-inflammatory tumor necrosis factor-α cytokine level measurements., Results: The MCAO model successfully replicated IR injury with significant histopathological changes, elevated tissue oxidative stress, and upregulated apoptotic and inflammatory protein expression in IR group compared to control group (p < 0.001). All parameters were significantly alleviated in IRr group compared to IR group (all p < 0.05). In IRu group, all parameters except for caspase-3 and Bcl-2 were also significantly different than IR group (all p < 0.05). The IRc group showed the biggest difference compared to IR group in all parameters (all p < 0.001). The IRc had higher superoxide dismutase and Bcl-2 levels, and lower caspase-3 levels compared to both IRr and IRu groups (all p < 0.05). Also, the IRc group had lower MDA and TNF-α levels compared to IRu group (all p < 0.05)., Conclusions: The results indicate that combined treatment of resveratrol and urapidil may be a novel strategy to downregulate neurodegeneration in cerebral IR injury.

Objective: The measurement of optic nerve sheath diameter is a noninvasive, practical, and economical method used to identify increased intracranial pressure. The purpose of this study is to detect the preoperative and postoperative changes in optic nerve sheath diameter in patients with intracranial mass, to correlate these changes with optic nerve diameter variations, and to evaluate the impact of hydrocephalus on these alterations., Material and Method: This study was conducted with patients who presented to our clinic with complaints of intracranial mass, were decided for surgery, and underwent surgical procedures., Findings: The optic nerve and optic nerve sheath diameter measurement values were different preoperatively and postoperatively, with a significant decrease in the optic nerve sheath diameter in all groups in postoperative measurements, while the optic nerve diameter significantly increased., Conclusions: Although there was no significant difference between the effects of hydrocephalus and intracranial mass-related increase in intracranial pressure on the optic nerve and optic nerve sheath, it was observed that hydrocephalus increased intracranial pressure when considering the Evans ratio. It has been determined that as ventricular dilatation increases, so does intracranial pressure, which leads to an increase in the diameter of the optic nerve sheath, resulting in papilledema and thinning of the optic nerve. These findings indicate the importance of early cerebrospinal fluid diversion and monitoring optic nerve sheath diameter in the management., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Aim: To validate a new particulate embolization method using degradable starch microspheres (DSM) and intraarterial exogenous amylase administration, which allow for regulated temporary cerebral arterial embolization without compromising tissue perfusion., Material and Methods: Twenty-four male New Zealand rabbits were randomly divided into three groups. All animals underwent routine angiography. The control group received no additional intervention. In the ischemia group, 0.2ml DSM was administered to the animals via the right carotid artery with pulsed, gentle injections to induce ischemia in the cerebral microcirculation. Animals in the reperfusion group received 0.05 ml of exogenous amylase along with DSM administration. Six hours after the procedure, the animals were sacrificed and histopathological analysis was performed., Results: The ischemia group was the most adversely affected group by embolization, with the highest number of pyknotic neurons. The reperfusion group, which received exogenous amylase, had lower pyknotic neurons than the ischemia group. The pyknotic neuron count was similar in some regions between reperfusion and control groups., Conclusion: Exogenous amylase can rapidly attenuate cerebral ischemia caused by microembolization with DSM.

Aim: To evaluate the protective effects of azathioprine, a macrophage-inhibiting agent, on secondary injury in spinal cord trauma., Material and Methods: A total of 40 Wistar rats were randomly divided into 4 groups. All the animals had undergone T8-10 laminectomy. Except in group I (control), all the animals were exposed to spinal cord trauma at the T9 level. Animals in group II (trauma) received no treatment following trauma. Animals in group 3 (treatment) and group IV (vehicle) were given intraperitoneal azathioprine 4 mg/kg and saline 2 ml, respectively, 30 minutes after the trauma. Half of the animals in each group were sacrificed 24 hours after injury and specimens were used for biochemical and immunohistochemical evaluations. The rest of the animals were followed-up for 4 weeks in terms of neurological functions and were also sacrificed to perform the histopathological analysis., Results: Significant decrease in apoptotic cells and improved neurological function were observed in the animals treated with azathioprine. Biological and immunohistochemical analysis also showed less oxidative stress in this group compared to those without treatment., Conclusion: Azathioprine, a potent macrophage-inhibiting agent, has been shown to decrease the extent of secondary injury following spinal cord trauma.

Aim: To evaluate the long-term outcomes and prognostic variables in a surgical cohort of pediatric meningiomas treated in a single institution., Material and Methods: Medical records and follow-up notes of 23 pediatric patients aged < 18 years (12 male and 11 female; mean age on presentation, 13.1 ± 4.4 years) harboring 27 meningiomas operated between 1994 and 01/2019 at Hacettepe University Ihsan Dogramaci Children’s Hospital were evaluated., Results: One patient had neurofibromatosis (NF) type 1, and five patients had NF2. Tumors were most commonly located in the convexity (n=6) and parasagittal or falcine (n=6). Gross total resection was performed in 70.4% of cases. WHO grade I tumors accounted for 56% of all cases, whereas high-grade meningiomas accounted for 44% (33% grade II, 11% grade III). The mean follow-up duration was 10.3 ± 7.7 years. Three patients (13%) died during follow-up, and 76.2% of the patients had favorable outcome (Glasgow Outcome Scale > 3) during the last follow-up assessment. Ten patients (43.5%) had relapse. In univariate analysis, low histological grade (p=0.030) and gross total resection (p=0.024) were associated with favorable outcome. The 10-year overall survival rate was 86%., Conclusion: Meningiomas in the pediatric age group are surgically treatable tumors with fairly good outcomes. However, relapses are common even for low-grade tumors; therefore, long-term surveillance and aggressive treatment are needed.

Aim: To share a single center experience with 27 atypical teratoid/rhabdoid tumor (AT/RT) cases, and to determine the effect of gross total tumor resection and other clinical characteristics on the overall survival rate of AT/RT., Material and Methods: We included 27 patients-with a histopathologically confirmed primary intracranial childhood AT/ RT-who were operated in our clinic between January 2000 and December 2017. Age, sex, tumor location, disseminated disease, the presence of hydrocephalus, symptom duration till diagnosis, the extent of resection, and adjuvant radiotherapy were evaluated for their influence on overall survival., Results: Median age at diagnosis for 27 patients was 19.1 months (7.2 months-5 years). Gross total resection was possible in 13 (48.72%) patients. Except for three patients who died of perioperative complications, all patients received chemotherapy and 11 received radiotherapy. In univariate analysis, male sex, older age at diagnosis (≥24 months), gross total resection, and radiotherapy were associated with overall longer survival; however, radiotherapy remained the only significant parameter in multivariate analysis., Conclusion: AT/RT is a rare and dreadful brain tumor that has low survival rates despite contemporary treatment. Radiotherapy seems to prolong survival; however, large-scale studies are needed to establish prognostic factors.

Objective: To investigate the concentrations of plasma cytokines and Galectin-3 (Gal-3) as inflammatory markers in patients with acute myocardial infarction (AMI)., Methods: The study population consisted of 29 patients with AMI and 29 healthy control subjects. We measured Gal-3, tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6) levels in plasma using enzyme-linked immunosorbent assays (ELISAs). We measured levels of C-reactive protein (CRP) via the nephelometric method., Results: Patients with AMI showed significantly higher plasma Gal-3, TNF-α, and IL-6 levels compared with controls. Gal-3 levels were positively and significantly correlated with plasma IL-6, TNF-α, and CRP levels in the control and patient groups., Conclusion: Our findings suggest that Gal-3 can be a new circulating biomarker of inflammation associated with AMI., (Copyright© by the American Society for Clinical Pathology (ASCP).)

Comparison of human and chimpanzee genomes has received much attention, because of paramount role for understanding evolutionary step distinguishing us from our closest living relative. In order to contribute to insight into Y chromosome evolutionary history, we study and compare tandems, higher order repeats (HORs), and regularly dispersed repeats in human and chimpanzee Y chromosome contigs, using robust Global Repeat Map algorithm. We find a new type of long-range acceleration, human-accelerated HOR regions. In peripheral domains of 35mer human alphoid HORs, we find riddled features with ten additional repeat monomers. In chimpanzee, we identify 30mer alphoid HOR. We construct alphoid HOR schemes showing significant human-chimpanzee difference, revealing rapid evolution after human-chimpanzee separation. We identify and analyze over 20 large repeat units, most of them reported here for the first time as: chimpanzee and human ~1.6 kb 3mer secondary repeat unit (SRU) and ~23.5 kb tertiary repeat unit (~0.55 kb primary repeat unit, PRU); human 10848, 15775, 20309, 60910, and 72140 bp PRUs; human 3mer SRU (~2.4 kb PRU); 715mer and 1123mer SRUs (5mer PRU); chimpanzee 5096, 10762, 10853, 60523 bp PRUs; and chimpanzee 64624 bp SRU (10853 bp PRU). We show that substantial human-chimpanzee differences are concentrated in large repeat structures, at the level of as much as ~70% divergence, sizably exceeding previous numerical estimates for some selected noncoding sequences. Smeared over the whole sequenced assembly (25 Mb) this gives ~14% human-chimpanzee divergence. This is significantly higher estimate of divergence between human and chimpanzee than previous estimates.

Serum total sialic acid (sTSA) has recently been shown to be a cardiovascular risk factor. However, there is little information about the role of sTSA and TSA in saliva in periodontitis, a chronic and inflammatory disease known to be a risk factor for cardiovascular disease (CVD). We aimed to investigate the changes in sTSA and TSA levels in saliva in patients having both periodontitis and CVD versus periodontitis patients without diagnosed CVD. The study group consisted of 26 patients with proven periodontitis and 26 controls with no diagnosed systemic disease but periodontitis. sTSA and saliva TSA levels were determined by the thiobarbituric acid method, and C-reactive protein (CRP) was evaluated by the nephelometric method. The severity of periodontitis has been determined by the community periodontal index of treatment needs (CPITN). TSA in blood and saliva and CRP levels in blood were significantly increased in CVD patients compared with the control group. CPITN ranged from 2 to 4 in both groups. Significant and positive correlations were found between sTSA and saliva SA levels in patients and controls and between tooth loss and TSA both in blood and saliva. Therefore, TSA in saliva may be a useful marker similar to sTSA in CVD patients., (Copyright © 2011 S. Karger AG, Basel.)

Since periodontitis is a chronic and inflammatory disease, a number of hypotheses have proposed that it has an etiological or modulating role in cardiovascular disease (CVD). This study aimed to ascertain the changes in the plasma levels of C-reactive protein (CRP) and protein C (PC), a natural anticoagulant also having an anti-inflammatory effect, in patients who have mild-to-severe periodontitis with or without CVD. The test group consisted of 26 patients with CVD and chronic periodontitis and the control group consisted of 26 patients with chronic periodontitis and no systemic disease. In both groups Community Periodontal Index of Treatment Needs scores were recorded and blood samples were collected. CRP levels were significantly high and PC activity was significantly low in the test group compared to the control group (p < 0.001). There was a negative correlation between tooth loss and PC and between CRP and PC. How PC is affected by the inflammatory events and its association with CRP is an active area of investigation., (Copyright © 2010 S. Karger AG, Basel.)

Background: Identification of approximate tandem repeats is an important task of broad significance and still remains a challenging problem of computational genomics. Often there is no single best approach to periodicity detection and a combination of different methods may improve the prediction accuracy. Discrete Fourier transform (DFT) has been extensively used to study primary periodicities in DNA sequences. Here we investigate the application of DFT method to identify and study alphoid higher order repeats., Results: We used method based on DFT with mapping of symbolic into numerical sequence to identify and study alphoid higher order repeats (HOR). For HORs the power spectrum shows equidistant frequency pattern, with characteristic two-level hierarchical organization as signature of HOR. Our case study was the 16 mer HOR tandem in AC017075.8 from human chromosome 7. Very long array of equidistant peaks at multiple frequencies (more than a thousand higher harmonics) is based on fundamental frequency of 16 mer HOR. Pronounced subset of equidistant peaks is based on multiples of the fundamental HOR frequency (multiplication factor n for nmer) and higher harmonics. In general, nmer HOR-pattern contains equidistant secondary periodicity peaks, having a pronounced subset of equidistant primary periodicity peaks. This hierarchical pattern as signature for HOR detection is robust with respect to monomer insertions and deletions, random sequence insertions etc. For a monomeric alphoid sequence only primary periodicity peaks are present. The 1/fbeta- noise and periodicity three pattern are missing from power spectra in alphoid regions, in accordance with expectations., Conclusion: DFT provides a robust detection method for higher order periodicity. Easily recognizable HOR power spectrum is characterized by hierarchical two-level equidistant pattern: higher harmonics of the fundamental HOR-frequency (secondary periodicity) and a subset of pronounced peaks corresponding to constituent monomers (primary periodicity). The number of lower frequency peaks (secondary periodicity) below the frequency of the first primary periodicity peak reveals the size of nmer HOR, i.e., the number n of monomers contained in consensus HOR.

Understanding the folding of centromere DNA in the maximally condensed methaphase chromosome remains a basic challenge in cell biology. We propose here a set of structural models with a graphical presentation of alphoid higher order repeat (HOR) distribution in the centromere folding, based on the assumption of encryption key for microtubule-centromere interaction which arises from chromosome-specific crystal-like structure of HORs. Specific HOR leads to a characteristic geometrical pattern which may be responsible for individual microtubule to recognize a specific structure of centromere in each chromosome.

Key string algorithm (KSA) could be viewed as robust computational generalization of restriction enzyme method. KSA enables robust and effective identification and structural analyzes of any given genomic sequences, like in the case of NCBI assembly for human genome. We have developed a method, using total frequency distribution of all r-bp key strings in dependence on the fragment length l, to determine the exact size of all repeats within the given genomic sequence, both of monomeric and HOR type. Subsequently, for particular fragment lengths equal to each of these repeat sizes we compute the partial frequency distribution of r-bp key strings; the key string with highest frequency is a dominant key string, optimal for segmentation of a given genomic sequence into repeat units. We illustrate how a wide class of 3-bp key strings leads to a key-string-dependent periodic cell which enables a simple identification and consensus length determinations of HORs, or any other highly convergent repeat of monomeric or HOR type, both tandem or dispersed. We illustrated KSA application for HORs in human genome and determined consensus HORs in the Build 35.1 assembly. In the next step we compute suprachromosomal family classification and CENP-B box / pJalpha distributions for HORs. In the case of less convergent repeats, like for example monomeric alpha satellite (20-40% divergence), we searched for optimal compact key string using frequency method and developed a concept of composite key string (GAAAC--CTTTG) or flexible relaxation (28 bp key string) which provides both monomeric alpha satellites as well as alpha monomer segmentation of internal HOR structure. This method is convenient also for study of R-strand (direct) / S-strand (reverse complement) alpha monomer alternations. Using KSA we identified 16 alternating regions of R-strand and S-strand monomers in one contig in choromosome 7. Use of CENP-B box and/or pJalpha motif as key string is suitable both for identification of HORs and monomeric pattern as well as for studies of CENP-B box / pJalpha distribution. As an example of application of KSA to sequences outside of HOR regions we present our finding of a tandem with highly convergent 3434-bp Long monomer in chromosome 5 (divergence less then 0.3%).

Aim: Tissue factor (TF) is a low-molecular-weight glycoprotein responsible for the initiation of the coagulation cascade. The relation between oxidized low-density lipoprotein (Ox-LDL), that has been shown to be involved in atherogenesis, and TF has not been evaluated before in circulating plasma. The aim of this study was to determine plasma levels of TF and Ox-LDL in acute coronary syndrome (ACS) and stable coronary artery disease (SCAD)., Methods: The study group consisted of 41 patients with ACS and 26 patients with SCAD. Among the ACS patients, 12 were diagnosed with unstable angina pectoris (UAP) and 29 were diagnosed with acute myocardial infarction (AMI). The control group consisted of 30 healthy volunteers. TF and Ox-LDL levels were evaluated by ELISA kits., Results: Ox-LDL levels were significantly higher in UAP and AMI patients compared with the control (p < 0.001) and SCAD (p < 0.01 and p < 0.001, respectively) groups. TF levels were significantly higher in the UAP, AMI and SCAD groups compared with the control group (p < 0.001, p < 0.001 and p < 0.01, respectively). In the AMI group a significant increase was observed in TF levels when compared with the SCAD group (p < 0.01). Plasma Ox-LDL levels were significantly and positively correlated with TF levels in the UAP and AMI groups (p < 0.05, r = 702, and p < 0.0001, r = 0.679, respectively)., Conclusion: The potential link between Ox-LDL and TF in circulating blood in ACS may strengthen the evidence supporting a relationship between oxidant stress, lipids and thrombosis and consequently may contribute to understanding the mechanism through which Ox-LDL and TF may mediate the pathogenesis of CAD., (Copyright 2010 S. Karger AG, Basel.)

Using our Key String Algorithm (KSA) to analyze Build 35.1 assembly we determined consensus alpha satellite higher-order repeats (HOR) and consensus distributions of CENP-B box and pJalpha motif in human chromosomes 1, 4, 5, 7, 8, 10, 11, 17, 19, and X. We determined new suprachromosomal family (SF) assignments: SF5 for 13mer (2211 bp), SF5 for 13mer (2214 bp), SF2 for 11mer (1869 bp), SF1 for 18mer (3058 bp), SF3 for 12mer (2047 bp), SF3 for 14mer (2379 bp), and SF5 for 17mer (2896 bp) in chromosomes 4, 5, 8, 10, 11, 17, and 19, respectively. In chromosome 5 we identified SF5 13mer without any CENP-B box and pJalpha motif, highly homologous (96%) to 13mer in chromosome 19. Additionally, in chromosome 19 we identified new SF5 17mer with one CENP-B box and pJalpha motif, aligned to 13mer by deleting four monomers. In chromosome 11 we identified SF3 12mer, homologous to 12mer in chromosome X. In chromosome 10 we identified new SF1 18mer with eight CENP-B boxes in every other monomer (except one). In chromosome 4 we identified new SF5 13mer with CENP-B box in three consecutive monomers. We found four exceptions to the rule that CENP-B box belongs to type B and pJalpha motif to type A monomers.

Motivation: GenBank data are at present lacking alpha satellite higher-order repeat (HOR) annotation. Furthermore, exact HOR consensus lengths have not been reported so far. Given the fast growth of sequence databases in the centromeric region, it is of increasing interest to have efficient tools for computational identification and analysis of HORs from known sequences., Results: We develop a graphical user interface method, ColorHOR, for fast computational identification of HORs in a given genomic sequence, without requiring a priori information on the composition of the genomic sequence. ColorHOR is based on an extension of the key-string algorithm and provides a color representation of the order and orientation of HORs. For the key string, we use a robust 6 bp string from a consensus alpha satellite and its representative nature is tested. ColorHOR algorithm provides a direct visual identification of HORs (direct and/or reverse complement). In more detail, we first illustrate the ColorHOR results for human chromosome 1. Using ColorHOR we determine for the first time the HOR annotation of the GenBank sequence of the whole human genome. In addition to some HORs, corresponding to those determined previously biochemically, we find new HORs in chromosomes 4, 8, 9, 10, 11 and 19. For the first time, we determine exact consensus lengths of HORs in 10 chromosomes. We propose that the HOR assignment obtained by using ColorHOR be included into the GenBank database.

Aim: To use a novel computational approach, Key-string Algorithm (KSA), for the identification and analysis of arbitrarily large repetitive sequences and higher-order repeats (HORs) in noncoding DNA. This approach is based on the use of key string that plays a role of an arbitrarily constructed "computer enzyme"., Method: A cluster of novel KSA-related methods was introduced and developed on the basis of a combination of computations on a very modest scale, by eye inspection and graphical display of results of analysis. Sequence analysis software was developed, containing seven programs for KSA-related analyses. This approach was demonstrated in the case study of alpha satellites and HORs in the human genetic sequence AC017075.8 (193277 bp) from the centromeric region of human chromosome 7. The KSA segmentation method was applied by using DCCGTTT, GTA, and TTTC key strings., Results: Fifty-five copies of 2734-bp 16mer HORs were identified and investigated, and a start-string TTTTTTAAAAA was identified. The HOR-matrix was constructed and employed for graphical display of mutations. KSA identification of HORs in AC017075.8 was compared with that of RepeatMasker and Tandem Repeat Finder, which identified alpha monomers in AC017075.8, but not the HORs. On the basis of KSA study, the centromere folding was described as an effect of HORs and super-HORs (3 x 2734 bp) in AC017075.8. The following novel computational KSA-based methods, easy-to-use and intended for computational "pedestrians", were demonstrated: color-HOR diagram, KSA-divergence method, 171-bp subsequence-convergence diagram, and total frequency distribution of the key-string subsequence lengths. The results were supplemented by Fast Fourier Transform, employing a novel mapping of symbolic genomic sequence into a numerical sequence., Conclusion: The KSA approach offers a simple and robust framework for a wide range of investigations of large repetitive sequences and HORs, involving a very modest scope of computations that can be carried out by using a PC. As the KSA method is HOR-oriented, the identification of HORs is even easier than the identification of underlying alpha monomer itself. This approach provides an easy identification of point mutations, insertions, and deletions, with respect to consensus. This may be useful in a wide range of investigations and applied in forensic medicine, medical diagnosis of malignant diseases, biological evolution, and paleontology.

32 children admitted to Hacettepe University Hospital for surgical treatment of vesicoureteral reflux (VUR) between 1987 and 1988 were included in this prospective double-blind study. All patients underwent intravenous urography (IVU), voiding cystouretrography and 99mTc DMSA renal scanning. The sensitivity and specificity of the DMSA scan and IVU for detecting renal scarring were investigated. With regard to the presence of renal scarring, the sensitivity and specificity of IVU and DMSA were not found to be statistically different. But when the scars were scored, DMSA was found to have a higher scoring index compared to IVU. In patients who were candidates for surgical management of VUR, renal scars could be detected both by IVU and DMSA scan but, for the follow-up, the DMSA scan was found to be the investigation of choice.

Mild vasovagal hypotension occurred in two normal male volunteers during insertion of indwelling venous cannulae. In spite of a rapid intravenous fluid load (3.6-4.6 litres in 90 min) both subjects passed little urine for 100 min. When the experiment was repeated without vasovagal hypotension, a rapid large diuresis followed the fluid load. The prolonged oliguria after vasovagal hypotension was the result of vasopressin release. This was demonstrated by measuring vasopressin in the blood and urine and by observing the renal response to a water load. The observation in man that a mild transient hypotensive episode may reduce urine flow for 100 min has clinical significance.