Cloves syndrome: a case report and perinatal diagnostic findings.

We report a neonate with prenatal ultrasound imaging features suggestive of CLOVES syndrome, confirmed postnatally by clinical and imaging findings of the constellation of truncal overgrowth, cutaneous capillary malformations, lymphatic and musculoskeletal anomalies. The clinical, radiological and histopathological findings noted in our patient help differentiate from other overgrowth syndromes such as Proteus syndrome. We report perinatal findings and add new clinical findings of this rare syndrome.

Partial trisomy 3p24.3 and partial monosomy 5p15.33: case report and a literature review.

We report on a preterm neonate with a deletion of the distal short arm of chromosome 5p15.33 and partial trisomy of the distal short arm of chromosome 3p24.3. The patient was the first-born monozygotic twin. There were no pertinent facial or physical features except a small lower lip hemangioma. The neonate presented with cardiac defects, which included a patent ductus arteriosus, an atrial septal defect and ventricular septal defects. After 94 days of age, however, the patient died from superior vena cava syndrome, recurrent chylothoraces and generalized anasarca. Array comparative genomic hybridization (aCGH) using a custom oligonucleotide microarray (Agilent 180,000 probe platform revealed a terminal duplication of 1,128 oligonucleotide probes from 3pter to 3p24.3, spanning approximately 20.4 megabases (Mb), and a terminal deletion of 271 oligonucleotide probes from 5pter to 5p15.33, spanning approximately 4.3 Mb. This is the first report of a patient with partial trisomy 3p24.3 and partial monosomy 5p15.33 without major dysmorphic features.

Spectrophotometric determination of tranexamic acid using vanillin.

A new spectrophotometric method has been examined for the determination of the tranexamic acid (TA) by derivatization with vanillin (VAN). The molar absorptivity of TA was calculated 25,160 L x mol(-1) x cm(-1) at lambdamax 354 nm and obeyed the Beer's law within 0.5-2.5 microg x mL(-1). The color reaction was highly stable and did not show any change in absorbance up to 24 h. The method was applied for the analysis of TA from capsules, injections and tooth pastes. The amounts of TA found in capsules, injections and tooth pastes of various pharmaceutical companies were observed with 249.0-250.9 mg/capsule, 249.3-250.7 mg/injection and 0.048%-0.049% in tooth pastes with relative standard deviation (RSD) 0.2%-5.0% (n = 3).

Serum cystatin C as a marker of renal function in patients with acute renal failure.

Serum creatinine level is the traditionally used tool to detect changes in renal function. Serum cystatin C (CC) has been suggested to be an equally effective marker of renal function. We measured the serum levels of creatinine and CC in 73 patients with acute renal failure (ARF) and 300 age and sex matched healthy controls. The serum CC was measured by particle enhanced nephlometric immunoassay (PENIA). As expected, the serum creatinine and CC levels were significantly higher in ARF patients than the healthy controls and serum CC levels correlated significantly with serum creatinine (r = 0.47, p< 0.0001). This correlation further increased for multiple measurements, (r = 0.51, p< 0.0001. No gender difference was noted. Serum CC also correlated significantly with calculated GFR. Correlation of serum CC with serum creatinine and calculated GFR was much greater in patients with deteriorating renal function, compared to patients with improving renal function (p< 0.0001). Our study further suggests that the serum CC is a good marker of renal function in ARF patients, especially those with worsening renal function. Further larger studies are needed to evaluate its role in detecting early ARF and institute possible intervention.

Dialyzer reuse impact on dialyzer efficiency, patient morbidity and mortality and cost effectiveness.

Since the introduction of dialyzer reuse more than three decades ago, several studies have reported its safety, efficacy and cost effectiveness. Reuse of hemodialyzer was prospectively studied in ten chronic hemodialysis (HD) patients recruited from the renal unit, the King Khalid University Hospital, Riyadh, Saudi Arabia, for three months. During the study period, 66 dialyzers were used for 408 sessions of HD, with a mean reuse of 6.2 +/- 5.3 episodes per dialyser, the mean of maximum reuse episodes being 13.7 +/- 8.0. The urea reduction ratio was maintained between 73 +/- 5% at baseline to 71.2 +/- 9.03% (p=0.53) at the maximum reuse. Similarly phosphate reduction with each HD session was maintained; mean decrease in phosphate levels was 0.67 mmol/L. Significant increase in heparin requirement was noted; however, the risk of bleeding was not increased. Hematocrit levels increased from 30.4 +/- 4.1% to 33.2 +/- 3.6% at the end of the study (p=0.6). Albumin leak in dialysate decreased with each reuse; baseline 8.27 +/- 7.93 mg/L to 2.8 +/- 0.4 mg/L at maximum reuse (p=0.04). Serum albumin levels remained stable. No short-term adverse effects on patients' morbidity and mortality were noted. Total cost savings of 53% was achieved with the reuse of dialyzers, excluding capital equipment used for preparation for reuse. In conclusion, dialyzer reuse seems to be safe and may provide an economical and efficient dialysis. Studies involving larger number of patients is required to validate this observation.

A buyer-seller watermarking protocol.

Digital watermarks have previously been proposed for the purposes of copy protection and copy deterrence for multimedia content. In copy deterrence, a content owner (seller) inserts a unique watermark into a copy of the content before it is sold to a buyer. If the buyer sells unauthorized copies of the watermarked content, then these copies can be traced to the unlawful reseller (original buyer) using a watermark detection algorithm. One problem with such an approach is that the original buyer whose watermark has been found on unauthorized copies can claim that the unauthorized copy was created or caused (for example, by a security breach) by the original seller. In this paper, we propose an interactive buyer-seller protocol for invisible watermarking in which the seller does not get to know the exact watermarked copy that the buyer receives. Hence the seller cannot create copies of the original content containing the buyer's watermark. In cases where the seller finds an unauthorized copy, the seller can identify the buyer from a watermark in the unauthorized copy and furthermore the seller can prove this fact to a third party using a dispute resolution protocol. This prevents the buyer from claiming that an unauthorized copy may have originated from the seller.

Secret and public key image watermarking schemes for image authentication and ownership verification.

We describe a watermarking scheme for ownership verification and authentication. Depending on the desire of the user, the watermark can be either visible or invisible. The scheme can detect any modification made to the image and indicate the specific locations that have been modified. If the correct key is specified in the watermark extraction procedure, then an output image is returned showing a proper watermark, indicating the image is authentic and has not been changed since the insertion of the watermark. Any modification would be reflected in a corresponding error in the watermark. If the key is incorrect, or if the image was not watermarked, or if the watermarked image is cropped, the watermark extraction algorithm will return an image that resembles random noise. Since it requires a user key during both the insertion and the extraction procedures, it is not possible for an unauthorized user to insert a new watermark or alter the existing watermark so that the resulting image will pass the test. We present secret key and public key versions of the technique.

Effect of intravenous cyclophosphamide pulse therapy on renal functions and histopathology in patients with severe lupus nephritis.

Despite the wide use of intravenous cyclophosphamide (IC) in lupus nephritis (LN), there are few published studies showing the effect of this treatment on renal histology. In this prospective study, we report the effect of IC on the evolution of histopathologic features in successive renal biopsies in patients with LN. Thirty patients with class IV or V LN were started on IC (10-15 mg/kg) administered once every month for six months followed by three monthly for another six doses making a total of two years of therapy. The clinical course of the disease, serum creatinine and 24 hours urinary protein and creatinine clearance were tested at entry and subsequently during each follow-up visit. Repeat renal biopsy was performed after completion of two years of therapy. The mean serum creatinine of the study patients was 166.3 + 42 tmol/L at entry which decreased to 104 + 46.4 tmol/L at two years (P + 2.4 g at entry to 1.39 + 1.54 g at two years (P + 31 ml/min at the start of treatment to 64 + 32 ml/min at two years of therapy (P 200 tmol/L, of whom six progressed to variable degrees of chronic renal failure. Repeat renal biopsy was performed in 21 patients. The original biopsy of these patients showed class IV in 17 and class V in four patients. On repeat biopsy, five of class IV disease had progressed to advanced sclerosis, four to class V, and five remained unchanged. The remaining three patients with class IV LN changed to one each of class I, II and III. Of the four patients with class V, one progressed to advanced sclerosis, one changed to class III and two remained the same. There was a significant decrease (P < 0.05) in the activity index although there was a significant increase in the chronicity index (P < 0.001). Multivariat analysis for possible risk factors for progression to chronic renal failure showed initial high serum creatinine to be a powerful predictor of renal failure. In conclusion, IC pulse therapy is effective in improving or stabilizing renal function in patients with class IV or V LN. The only poor prognostic determinant observed was higher initial serum creatinine value.

Prevalence of glomerular diseases: king khalid university hospital, saudi arabia.

To obtain a more recent and comprehensive insight into the prevalence of glomerular diseases in our patient population, medical records of 200 patients with biopsy proven glomerulonephritis (GN), between January 1994 and June 1999, at the King Khalid University Hospital, Riyadh, Saudi Arabia were analyzed. Primary glomerular disease was found to be the most prevalent, accounting for 63.5% of all glomerular diseases. Among primary glomerular diseases, focal and segmental glomerulosclerosis (FSGS) was the most common histological lesion (34.6%) and was associated with a high prevalence of hypertension (86.4%), nephrotic syndrome (68.18%), hematuria (63.6%) and renal functional impairment (27.3%). Mesangioproliferative GN was the second most common lesion (25.1%) followed by mesangiocapillary GN (15.7%), IgA nephropathy (10.2%), and minimal change disease (8.5%). Amongst secondary glomerular diseases, lupus nephritis was the most prevalent (24.5%). In conclusion, primary glomerular diseases constituted the commonest group encountered and the prevalence of FSGS was quite high with male sex and young adults predominating. FSGS was also associated with a high prevalence of end-stage renal disease. Further collaborative studies are necessary to explore the predisposing factors and associations of glomerular disease, especially FSGS.

Counterfeiting attacks on oblivious block-wise independent invisible watermarking schemes.

In this paper, we describe a class of attacks on certain block-based oblivious watermarking schemes. We show that oblivious watermarking techniques that embed information into a host image in a block-wise independent fashion are vulnerable to a counterfeiting attack. Specifically, given a watermarked image, one can forge the watermark it contains into another image without knowing the secret key used for watermark insertion and in some cases even without explicitly knowing the watermark. We demonstrate successful implementations of this attack on a few watermarking techniques that have been proposed in the literature. We also describe a possible solution to this problem of block-wise independence that makes our attack computationally intractable.

Context-based lossless interband compression--extending CALIC.

This paper proposes an interband version of CALIC (context-based, adaptive, lossless image codec) which represents one of the best performing, practical and general purpose lossless image coding techniques known today. Interband coding techniques are needed for effective compression of multispectral images like color images and remotely sensed images. It is demonstrated that CALIC's techniques of context modeling of DPCM errors lend themselves easily to modeling of higher-order interband correlations that cannot be exploited by simple interband linear predictors alone. The proposed interband CALIC exploits both interband and intraband statistical redundancies, and obtains significant compression gains over its intrahand counterpart. On some types of multispectral images, interband CALIC can lead to a reduction in bit rate of more than 20% as compared to intraband CALIC. Interband CALIC only incurs a modest increase in computational cost as compared to intraband CALIC.

An analysis of some common scanning techniques for lossless image coding.

Though most image coding techniques use a raster scan to order pixels prior to coding, Hilbert and other scans have been proposed as having better performance due to their superior locality preserving properties. However, a general understanding of the merits of various scans has been lacking. This paper develops an approach for quantitatively analyzing the effect of pixel scan order for context-based, predictive lossless image compression and uses it to compare raster, Hilbert, random and hierarchical scans. Specifically, for a quantized-Gaussian image model and a given scan order, it shows how the encoding rate can be estimated from the frequencies with which various pixel configurations are available as previously scanned contexts, and from the corresponding conditional differential entropies. Formulas are derived for such context frequencies and entropies. Assuming an isotropic image model and contexts consisting of previously scanned adjacent pixels, it is found that the raster scan is better than the Hilbert scan which is often used in compression applications due to its locality preserving properties. The hierarchical scan is better still, though it is based on nonadjacent contexts. The random scan is the worst of the four considered. Extensions and implications of the results to lossy coding are also discussed.

Context-based lossless and near-lossless compression of EEG signals.

In this paper, we study compression techniques for electroencephalograph (EEG) signals. A variety of lossless compression techniques, including compress, gzip, bzip, shorten, and several predictive coding methods, are investigated and compared. The methods range from simple dictionary-based approaches to more sophisticated context modeling techniques. It is seen that compression ratios obtained by lossless compression are limited even with sophisticated context-based bias cancellation and activity-based conditional coding. Though lossy compression can yield significantly higher compression ratios while potentially preserving diagnostic accuracy, it is not usually employed due to legal concerns. Hence, we investigate a near-lossless compression technique that gives quantitative bounds on the errors introduced during compression. It is observed that such a technique gives significantly higher compression ratios (up to 3-bit/sample saving with less than 1% error). Compression results are reported for EEG's recorded under various clinical conditions.

Dual-lumen femoral vein catheterization as vascular access for hemodialysis--a prospective study.

Prospectively from January 1991 to January 1993, the efficacy and complications of 104 polyurethane, double-lumen femoral vein catheterizations (FVC) in 96 renal failure patients were studied. Ambulation was allowed in the hospital as well as at home while the catheter was in. There were 53 males and 43 females, with ages ranging from 13 to 87 (mean, 48.3 +/- 19.7) years. Forty-eight patients had chronic renal failure and 48 had acute renal failure. The catheters were used for 1 to 26 days (mean, 8 +/- 5 days). Fifty-two (50%) of the FVC were used for 2 weeks and 14 (13.5%) for 3 weeks or longer. The various complications encountered were infection (n=31), poor blood flow (n=8), displaced catheter (n=6), thrombosis of the catheter (n=4), hematoma (n=4), bleeding (n=3), exit site infection (n=3), ileofemoral vein thrombosis (n=2), and tear in the catheter wall (n=2). On removal, bacterial colonization was present in 34 out of 93 catheter tips (36.5%); Staphylococcus epidermidis (n=12) was the commonest organism grown. There was no significant difference of infection between diabetic and nondiabetic chronic renal failure patients. The duration of catheterization was found to have no relation with either thrombosis or infection. Femoral vein catheters can be used for hemodialysis for 2 to 3 weeks and ambulation during cannulation may be allowed.

Peritonitis in Patients on CAPD at King Khalid University Hospital: Less Infection-rate with More Center-experience.

Continuous ambulatory peritoneal dialysis (CAPD) was started at the King Khalid University Hospital in 1986. Peritonitis remains the most significant complication of the procedure. Earlier rates of peritonitis were high, but after gaining sufficient experience, the rates are declining. To evaluate the change in peritonitis trend, 55 new patients who were recruited to our CAPD program between the periods October 1993-October 1996 were analyzed for the development of peritonitis on annual basis. There were 37 (67%) males and 18 (33%) females with a mean age of 43.3 years (range 12-72 years). A total of 34 episodes of peritonitis were recorded with a rate of 1.5 episode/patients year in 1993, 0.5 episode/patient year in 1994 and 0.8 in 1995. only 40% of episodes showed positive cultures whereas 60% remained culture-negative despite use of recommended modified culture techniques. Organisms causing peritonitis included staphylococcus eipdermides (6.7%), E. coli (3.3%), Streptococcus fecalis (3.3%) and pseudomonas (6.7%). Out of 34 episodes of peritonitis, 29 (85.3%) showed response to treatment and five episodes could only be treated after removal of catheter. Of the 29 episodes that responded to treatment, three relapsed and one had recurrent infection . However, all were successfully treated though one responded only after removal of catheter. Thus, a total of six catheters (20%) necessitated removal and replacement. In spite of high diabetic patients population in our series (27.2%) only one died of peritonitis related sepsis and another died of myocardial infarction after clearing the infection. Thus mortality remains low in spite of potential risk. Although we still use straight system CAPD rather than Y system peritonitis rates have declined considerable and we hope that the procedure will gain more acceptability amongst patients with ESRD in Saudi Arabia.

Sarcoidosis with partial reversibility of renal failure: two case reports with review of literature.

Sarcoidosis is one of the granulomatus disorders affecting many organ systems of the body. Renal impairment in sarcoidosis is rare and occurs usually as a result of long standing hypercalcemia or hypercalciuria with nephrocalcinosis or renal stones. Sarcoid glomerulopathy and tubulo-interstitial granulomatus involvement have been described. We report two cases of sarcoidosis, the first with interstitial nephritis and anterior uveitis without evidence of granuloma. The patient was normocalcemic and normocalciuric. The second case presented with nephritic range proteinuria and severe renal insufficiency with a history of recurrent parotid swelling seven years before diagnosis. Renal biopsy showed non-caseating granulomas in the tubulo-interstitial region. Both patients showed good response to steroid therapy, however, there is still residual renal insufficiency six months after therapy. In conclusion, renal sarcoidosis although a rare presentation, should be considered in the presence of extra-renal manifestation of sarcoidosis as it is amenable to treatment.

Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients.

High serum fluoride (F-) in patients with chronic renal failure (CRF) and end-stage renal disease (ESRD) is associated with risk of renal osteodystrophy and other bone changes. This study was done to determine F- in normal healthy controls and patients with ESRD on haemodialysis (HD) or peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females) and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l) of F- content in drinking water. Control subjects showed a mean serum F- concentration of 1.08 +/- 0.350 microM/l. Males in control group showed slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F- concentration did not correlate significantly with age and sex among control subjects, whereas such correlation was observed in patients with ESRD on dialysis. Mean serum F- concentration was significantly higher in patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal controls. When grouped according to sex, the mean serum F- concentration in males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped according to age, it was observed that F- concentration was significantly higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated with age and sex, being higher in males and above 20 years. Despite appreciable clearance of F- (39-90%) across the peritoneum, patients on CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs 2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their serum F- concentration above 3.0 microM/l, posing the risk of renal osteodystrophy.

Effect of recombinant human erythropoietin on lymphocyte phenotyping and phagocyte activity in hemodialysis patients.

The effect of recombinant human erythropoietin (rHmEPO) on lymphocytic phenotyping as well as on the phagocyte activity of polymorphonuclear cells and monocytes was evaluated in 16 patients on maintenance hemodialysis. The mean age of the patients was 38.2 +/- 16.2 years. There were seven men and nine women. All patients were started on 50 U/kg of rHmEPO intravenously three times per week, and the dosage was increased gradually to achieve target haemoglobin of 12 g/dL. Predialysis blood samples were taken monthly for 3 months, and phagocyte respiratory burst as well as lymphocyte subsets were studied. Healthy blood donors were taken as controls. By 3 months of rHmEPO treatment, there was no significant increase in total T and B cells, but there was a significant increase in both CD4 (P < 0.001) and CD8 (P < 0.005): however, there was no significant change in the CD4/CD8 ratio. There was significant reduction in the natural killer cells (P < 0.005). The phagocyte activity studies showed a significant increase in the respiratory burst in whole blood (P < 0.001) and opsonized zymosan (P < 0.001) as well as improvement in the suppressed polymorphonuclear cell and monocyte activity by uremia. Phagocytosis studied by yeast uptake showed significant improvement from the pretreatment suppressed phagocytes to normal activity posttreatment. In conclusion, treatment with rHmEPO increases CD4 and CD8 cell counts without affecting the CD4/CD8 ratio, decreases the natural killer cells, and improves the impaired phagocyte activity in hemodialysis patients.

Long-term effect of intravenous calcitriol on the treatment of severe hyperparathyroidism, parathyroid gland mass and bone mineral density in haemodialysis patients.

We conducted this study on 15 chronic haemodialysis patients to evaluate the efficacy of i.v. calcitriol over a 1-year period in the treatment of severe secondary hyperparathyroidism (HPT), in particular its effect on bone mineral density (BMD) and parathyroid gland mass. Mean age was 39 +/- 11.9 (20-65) years and dialysis duration was 58 +/- 3 (19-130) months. i.v. calcitriol was given at a dose of 1 microg post-dialysis 3 times/week for 3 weeks; the dose was then adjusted to maintain the total serum calcium at less than 2.88 mmol/l. The maximum dose was 3 microg 3 times/week. Serum calcium (Ca) and phosphorus (P) were determined prior to treatment, then weekly for 6 weeks and every 2 weeks thereafter. Skeletal survey, dual photon densitometry and parathyroid ultrasound (US) were done prior to treatment and after 1 year. Bone biopsy was done in 10 patients at the beginning of treatment. There was a significant reduction (p < 0.01) in pre-treatment mid-region serum parathyroid hormone (PTH) from 1,476 +/- 895 to 489 +/- 485 P mol/l, as well as alkaline phosphatase (p < 0.04) from 236.5 +/- 221 to 116.3 +/- 49 U/l. This was without a significant increase in serum Ca (2.15 +/- 0.25 to 2.44 +/- 0.26 mmol/l, p = 0.08). Three patients had recurrent hypercalcaemia which responded to reduction of Ca in dialysate. There was a significant increase in BMD over the spine from 1.071 +/- 0.25 to 1.159 +/- 0.22 g/cm2 (p < 0.003) with a percent increase of 9.3 +/- 8.9% as well as over the femoral neck from 0.834 +/- 0.002 to 0.89 +/- 0.09 g/cm2 (p < 0.001) with a percent increase of 7.45 +/- 6.81%. Five patients had enlarged parathyroid glands by US and in 3 of these, there was a significant reduction to normal with treatment. Bone biopsy was done in 10 patients. Six patients had predominant hyperparathyroid bone disease and 4 had mixed uraemic osteodystrophy. In conclusion, long-term i.v. treatment with calcitriol is effective in the treatment of severe secondary HPT. PTH decreased without a significant increase in serum Ca. BMD also increases during this therapy.