Retraction: Isolated Polycystic Liver Disease: A Rare Genetic Disorder.

[This retracts the article DOI: 10.7759/cureus.18560.].

Complete Currarino Triad Presenting With Chronic Constipation.

Currarino syndrome (CS) is a congenital disorder that is characterized by the triad of anorectal malformation, sacrococcygeal anomalies, and a presacral mass. The inheritance of CS is autosomal dominant. Chronic constipation is the most common symptom of CS. MRI is considered the most sensitive test to diagnose CS. The report describes an eight-month-old baby girl who presented with chronic constipation. Physical examination showed abdominal distension and anal stenosis. Plain radiographs and MRI revealed sacrococcygeal abnormalities with a presacral mass. A patient was diagnosed with Currarino syndrome and managed surgically with excision of the presacral mass and an anorectoplasty via a posterior sagittal midline incision.

Isolated Polycystic Liver Disease: A Rare Genetic Disorder.

Polycystic liver disease is a rare clinical condition that causes portal hypertension. It constitutes a group of disorders with liver lesions resulting from abnormal development of the embryological ductal system. Isolated polycystic disease with the absence of polycystic kidney disease is considered a rare condition. We present the case of a 46-year-old man who presented with epigastric pain and episodes of hematemesis. Abdominal examination revealed enlarged liver. He underwent a computed tomography scan that revealed innumerable cystic liver lesions with the presence of ascites. Further investigations confirmed abnormal liver functions and portal hypertension. Physicians need to consider this diagnosis in the appropriate clinical settings. Extensive involvement of the liver may lead to persistent severe symptoms requiring liver transplantation.

Toward physiologically motivated registration of diagnostic CT and PET/CT of lung volumes.

PURPOSE: Current clinical practice for lung cancer diagnosis and staging requires the acquisition of a diagnostic computed tomography (CT) as well as positron emission tomography (PET)/CT volumes from a hybrid scanner, where the CT is used for attenuation correction (AC-CT). The PET and AC-CT images are implicitly aligned, however, image registration between the diagnostic CT and PET volumes is needed to relate the anatomical correspondences. This is an important but difficult task due to the absence of a direct or functional relationship between the intensities. Alternatively, here we propose the diagnostic CT can be aligned with the PET image through an indirect registration process that uses the AC-CT. The resultant deformation field can then be used to align the PET image to the diagnostic CT. The registration of the diagnostic CT to AC-CT registration still presents two major challenges: (a) it is a multimodal registration problem since the diagnostic CT is acquired after the injection of a contrast agent, and (b) the type and amplitude of the deformations require a registration process that includes physically motivated properties to achieve an accurate and physiologically plausible alignment. METHODS: The authors propose a new framework based on fluid registration including three physiologically motivated properties: (i) sliding motion of the lungs against the pleura; (ii) preservation of rigid structures; (iii) preservation of topology. The sliding motion is modeled using direction dependent regularization that decouples the tangential and the normal components of the external force term. The rigid shape of the bones is preserved using a spatially varying filter for the deformations. Finally, the topology is maintained using the concept of log-unbiased deformations. To solve the multimodal problem, the authors use local cross correlation (LCC) as the similarity measure. RESULTS: The proposed framework is first evaluated on CT lung image pairs representing several phases of the respiratory cycle. The authors show that their proposed framework has a superior performance compared to the classic fluid registration, both in quantitative and qualitative terms. The authors then evaluate the framework using ten real patient scans, where the authors also demonstrate how their physiologically motivated registration framework can be successfully applied to the task of fusing diagnostic CT with the PET/CT image volumes. CONCLUSIONS: The proposed registration framework has better results for the fusion of diagnostic CT with PET images in comparison to the classic fluid registration framework.

Piecewise-diffeomorphic image registration: application to the motion estimation between 3D CT lung images with sliding conditions.

In this paper, we propose a new strategy for modelling sliding conditions when registering 3D images in a piecewise-diffeomorphic framework. More specifically, our main contribution is the development of a mathematical formalism to perform Large Deformation Diffeomorphic Metric Mapping registration with sliding conditions. We also show how to adapt this formalism to the LogDemons diffeomorphic registration framework. We finally show how to apply this strategy to estimate the respiratory motion between 3D CT pulmonary images. Quantitative tests are performed on 2D and 3D synthetic images, as well as on real 3D lung images from the MICCAI EMPIRE10 challenge. Results show that our strategy estimates accurate mappings of entire 3D thoracic image volumes that exhibit a sliding motion, as opposed to conventional registration methods which are not capable of capturing discontinuous deformations at the thoracic cage boundary. They also show that although the deformations are not smooth across the location of sliding conditions, they are almost always invertible in the whole image domain. This would be helpful for radiotherapy planning and delivery.

Single wire radial junction photovoltaic devices fabricated using aluminum catalyzed silicon nanowires.

Single nanowire radial junction solar cell devices were fabricated using Si nanowires synthesized by Al-catalyzed vapor-liquid-solid growth of the p(+) core (Al auto-doping) and thin film deposition of the n(+)-shell at temperatures below 650 °C. Short circuit current densities of 11.7 mA cm(-2) were measured under 1-sun AM1.5G illumination, showing enhanced optical absorption. The power conversion efficiencies were limited to < 1% by the low open circuit voltage and fill factor of the devices, which was attributed to junction shunt leakage promoted by the high p(+)/n(+) doping. This demonstration of a radial junction device represents an important advance in the use of Al-catalyzed Si nanowire growth for low cost photovoltaics.

Comparison of the fit of Procera crowns made from stone with those made from polyurethane resin.

This study compared the average marginal gap of Procera crowns fabricated from a definitive cast made from polyurethane resin with those made from type IV stone. A metallic maxillary central incisor and first premolar were prepared according to the Procera guidelines and incorporated into a U-shaped definitive cast. From this definitive cast, 20 primary casts were made in polyurethane resin. Two sets of impressions (10 with type IV stone and 10 with polyurethane resin) were made and poured onto these casts. Forty pure aluminum oxide substructures for Procera crowns were made for these groups, with 10 incisors and 10 premolars in each group. Each substructure was cemented on the respective primary die and sectioned. Using an optical microscope and special software, sections were measured and compared for marginal adaptation. Based on the findings, both materials were equally adequate for producing a Procera crown. However, the mean margin gap was consistently larger for type IV stone dies than for polyurethane resin dies.

In vitro evaluation of the "replica technique" in the measurement of the fit of Procera crowns.

AIM: The objective of this study was to compare the film thickness of a light body polyvinylsiloxane addition silicone impression material using the "replica technique" (RT) to the film thickness resulting from the cementation of Procera copings. METHODS AND MATERIALS: Twenty Procera copings were fabricated on ten casts each having one central incisor and one premolar. The thickness of the light body was first measured using the RT; then on the same casts dies were cemented with glass-ionomer cement, sawed, and the film thickness of cement was measured. These two materials were expected to behave differently under stress according to their respective physical properties. RESULTS: The thickness of silicone material did not differ significantly from that of the glass-ionomer cement used in this experiment. Also, when the two groups of central incisors and premolars were taken separately, at three different areas (occlusal, axial, and cervical), no significant difference was found. Only when each surface (buccal, palatal, mesial, and distal) was compared separately at the cervical area, some significant differences between the two techniques was detected. CONCLUSION: Within the limitations of this study, the RT is an accurate and reliable technique that can simulate crown gap space after cementation. CLINICAL SIGNIFICANCE: The RT is reliable for evaluating cement thickness at the marginal and internal gaps of Procera AllCeram crowns during try-in sessions.

Production of inert cushioning beads: effect of excipients on the physicomechanical properties of freeze-dried beads containing microcrystalline cellulose produced by extrusion-spheronization.

Conventional highly compactible fillers such as microcrystalline cellulose (MCC) can be mixed with drug-loaded membrane-coated beads and compressed to form a tablet. However, due to particle size differences, there is substantial risk of segregation leading to weight variation and content uniformity problems. Furthermore, whenever modified release beads are included in a tablet matrix, care must be taken to assure the integrity of the coated beads. This paper describes the development of placebo beads containing MCC whose properties make them uniquely suitable for tableting modified release beads. These placebo beads have high compactibility and the ability to rapidly disintegrate. They deform readily and may provide a high degree of protection to drug-loaded membrane-coated beads during compression ('cushioning effect'). They can be produced in size ranges that provide minimal segregation propensity. Beads containing different MCC/lactose ratios and different types and levels of superdisintegrants were produced by extrusion-spheronization followed by freeze drying. The presence of high levels of MCC and different superdisintegrants, especially croscarmellose sodium, increased the granulation liquid requirement, thus producing freeze-dried beads with higher porosities and compactibility. Athy-Heckel analysis studies revealed that beads rich in MCC exhibited lower mean yield pressures than those containing high levels of lactose. The freeze-dried beads exhibited both plastic deformation and brittle fracture characteristics.

Gene deletion patterns in spinal muscular atrophy patients with different clinical phenotypes.

Spinal muscular atrophy (SMA) is an autosomal recessive disorder characterized by degeneration of lower motor neurons. We have assayed deletions in two candidate genes, the survival motor neuron (SMN) and neuronal apoptosis inhibitory protein (NAIP) genes, in 108 samples, of which 46 were from SMA patients, and 62 were from unaffected subjects. The SMA patients included 3 from Bahrain, 9 from South Africa, 2 from India, 5 from Oman, 1 from Saudi Arabia, and 26 from Kuwait. SMN gene exons 7 and 8 were deleted in all type I SMA patients. NAIP gene exons 5 and 6 were deleted in 22 of 23 type I SMA patients. SMN gene exon 7 was deleted in all type II SMA patients while exon 8 was deleted in 19 of 21 type II patients. In 1 type II SMA patient, both centromeric and telomeric copies of SMN exon 8 were deleted. NAIP gene exons 5 and 6 were deleted in only 1 type II SMA patient. In 1 of the 2 type III SMA patients, SMN gene exons 7 and 8 were deleted with no deletion in the NAIP gene, while in the second patient, deletions were detected in both SMN and NAIP genes. None of the 62 unaffected subjects had deletions in either the SMN or NAIP gene. The incidence of biallelic polymorphism in SMN gene exon 7 (BsmAI) was found to be similar (97%) to that (98%) reported in a Spanish population but was significantly different from that reported from Taiwan (0%). The incidence of a second polymorphism in SMN gene exon 8 (presence of the sequence ATGGCCT) was markedly different in our population (97%) and those reported from Spain (50%) and Taiwan (0%).

Canadians without regular medical doctors. Who are they?

OBJECTIVE: Because having a regular medical doctor is associated with positive outcomes, this study attempted to determine the characteristics of Canadians without regular doctors so that alternative methods of delivering care to people with those characteristics can be studied. DESIGN: Secondary data analysis of the National Population Health Survey using bivariate analyses and logistic regression. PARTICIPANTS: A total of 15,777 respondents older than 20 years. MAIN OUTCOME MEASURES: Responses to the question "Do you have a regular medical doctor?" and analysis of 11 variables covering demographics, health status, and lifestyle factors. RESULTS: One in seven respondents did not have a regular doctor. Younger respondents, men, single people, poorer respondents, respondents who perceived themselves in better health, recent immigrants, those without confidants, and smokers were more likely not to have regular doctors. Comparing provinces, participants from Quebec were least likely to have regular doctors. CONCLUSION: Primary care reform might need to consider alternative ways of providing care to certain people. Future primary care programs could be targeted to improve coverage of relatively underserviced people, particularly men, people on low incomes, those without confidants, and recent immigrants.

Is silicified wet-granulated microcrystalline cellulose better than original wet-granulated microcrystalline cellulose?

The purpose of this study was to investigate the effect of granulating water level on the physical-mechanical properties of microcrystalline cellulose (MCC) and silicified microcrystalline cellulose (SMCC). Granulations containing either MCC or SMCC were manufactured at different water levels using a high-shear mixer and were then tray-dried. The water level ranged from 0 to 100%. The granules were evaluated for size, granular and true density, porosity, flow, compactibility, compressibility, and strain-rate sensitivity index (SRS). Increasing the water level affected the size, increased the granular density and flow properties of the granules, and decreased the porosity and compactibility. The compactibilities for both materials were similar and acceptable at each granulating water level up to 40%. They both showed poor compactibility at higher water levels. Yield values and SRSs revealed that MCC and SMCC have similar compressibility, and that both exhibit a plastic component to the deformation process. The granulating water level had no statistically significant effect on the compressibility or the SRS for MCC or SMCC. SMCC did not offer practical advantages over MCC, other than better flow in the powder form, which could be attributed to slightly larger particle size and the presence of silicon dioxide in its structure.

Bartter's syndrome in Arabic children: review of 13 cases.

BACKGROUND: Bartter's syndrome (BS) is an inherited disease of renal potassium wasting characterized by hypokalemic alkalosis, normal blood pressure, vascular insensitivity to pressor agents and elevated plasma concentrations of renin and aldosterone. It is caused by generalized hyperplasia of the juxtaglomerular apparatus at the site of renin production caused by mutations in the Na-K-2Cl cotransporter gene, NKCC2. The objective of our study is to establish the prevalence and incidence of BS in Kuwait and to assess treatment modalities for it. METHODS AND RESULTS: Bartter's syndrome was diagnosed in 13 Kuwaiti children over a 14 year period (1981-1995) with the estimated incidence of 1.7/100,000 live births. The mean age at diagnosis was 9.3 months (range 2-32 months). There were five males and eight females (ratio 1:1.6). The mean duration of follow up was 5.6 years (1-14 years). Both consanguinity and familial history among our patients were high (69 and 54%, respectively). All patients had hypokalemia, hypochloremia with metabolic alkalosis, hyperreninemia and were normotensive. Clinical presentation was essentially similar to that in other series. Eleven patients (85%) had growth failure, two had nephrocalcinosis (15%) and one had renal failure. All patients were treated with supplemental potassium, an aldosterone antagonist (spironolactone) and a prostaglandin synthetase inhibitor (indomethacin or aspirin) sequentially. Significant catch-up of growth (four patients) and increases in serum potassium (eight patients) were recorded after administration of indomethacin therapy. One patient died of severe pneumonia with respiratory failure from hypokalemic myopathy. Clinical presentation, inheritance, complications and therapy of BS are briefly discussed. CONCLUSION: Bartter's syndrome is a rare disease, but should be considered in the differential diagnosis of other disorders with growth failure and/or hypokalemia. Early diagnosis, close follow up and compliance with treatment may lead to appropriate growth and development.

Screening 25 dystrophin gene exons for deletions in Arab children with Duchenne muscular dystrophy.

Forty-two Arab children with Duchenne muscular dystrophy (DMD) were studied for intragenic deletions in 25 exons of the dystrophin gene using three different multiplex PCR sets each amplifying a total of 9, 9 and 6 different exons, respectively. Exon 22 was amplified individually. Deletions were found in 78, 76 and 12% of DMD patients with each of the three sets, respectively. With all the three sets, the detection rate increased to 86% (36 of 42 patients). Fifty percent of the deleted exons were located in the distal hot spot, 8% in the proximal hot spot while 42% were scattered over both. This study, the first in an Arab population and only the second to use three PCR multiplex sets, documents one of the highest deletion detection rates in DMD.

Dilution potential: a new perspective.

The objective of this work was to develop a method to assess the dilution capacity of direct compression excipients based on a technique previously proposed by Minchom and Armstrong (MA). The technique involves the addition of increasing quantities of a poorly compactible (compressible) material to the excipient and measuring the resultant decrease in the AUC of the tensile strength versus compaction force profiles. The AUC of each mixture is divided by the AUC of the "0% mixture" to obtain MA's "work potential," called "area ratios" in the present study. The applicability of this approach was tested using three excipients differing in their deformation mechanisms: microcrystalline cellulose (Avicel PH 101, 102, 200, 301, 302) representing a plastic material; dibasic calcium phosphate (Cal-Star) representing a brittle material, and anhydrous lactose, which exhibits both brittle and plastic properties. Ascorbic acid or acetaminophen was the poorly compactible challenge material. In the first study, the MA method was found to apply only to Avicel PH 101, since the area ratios for mixtures containing different compositions of acetaminophen with either Cal-Star or anhydrous lactose remain constant until a certain percentage of drug is exceeded, after which a decline starts to be observed. Further work carried out on mixtures of different grades of Avicel with ascorbic acid revealed that MA's approach reflects only the ability of the excipient to handle internal stress induced by the drug and does not take into account the intrinsic ability of the drug-free excipient to form strong compacts. A new index was thus proposed, called the dilution capacity index (DCI), which weights the MA index by the AUC of the drug-free excipient. The results suggest that DCI can be used to compare different grades of microcrystalline cellulose and provide in-house quality control for microcrystalline cellulose suppliers.

Role of atrial natriuretic factor in sodium and water retention in patients with schistosomal hepatic fibrosis.

Fifty subjects divided into three groups were studied: Group I: 10 normal adult subjects as controls. Group II: 20 patients with schistosomal hepatic fibrosis (SHF) without ascites (compensated stage). Group III: 20 patients with SHF with ascites. In all these patients plasma atrial natriuretic factor (ANF), serum aldosterone and serum osmolality were determined. There was a significant decrease in the plasma ANF in groups II and III compared to group I. There was a significant increase in the serum aldosterone level in group III compared to groups I and II. No significant difference was noted in serum sodium and potassium levels among the three groups. There was a significant decrease in serum osmolality in groups II and III compared to group I.

The prognostic value of the brain sodium-potassium ATPase enzyme concentration in head injury.

Sodium-potassium adenosine triphosphatase (ATPase) enzyme was determined in the brain tissue of 11 patients with head injury and 6 control patients. Patients with head injury included in this study were selected from two categories: (a) patients in deep coma due to severe head injury [Glasgow Coma Scale (GCS) less than 8; 6 cases]; (b) patients with depressed skull fractures with dural tears who were conscious and able to give an adequate verbal response (GCS greater than 10; 5 cases). The level of the enzyme was significantly reduced in comatose patients with severe head injury as compared to the controls (P less than 0.001) or to conscious patients with depressed fractures (P less than 0.001). In the group of conscious patients with depressed fractures, the enzyme level was no different from that of the controls (P = 0.4215). All comatose patients with severely reduced enzyme levels subsequently died, whereas those with depressed fractures with normal enzyme levels survived. The relationship between a low enzyme level and brain edema in severe head injury is discussed.