Isolation and characterization of a process impurity in tizanidine hydrochloride

A new process impurity was detected during the HPLC analysis of Tizanidine hydrochloride (I) batches. The impurity (II) was isolated by preparative HPLC and characterized by NMR and Mass spectral analysis as 5-S-ethyl-N-(4,5-dihydro-1H-imidazol-2-yl)-2,1,3-benzothiadiazol-4-amine hydrochloride.

Periosteal pedicle graft for the treatment of gingival recession defects: a novel technique

BACKGROUND

The periosteum is a highly cellular connective tissue with rich vascularity and regenerative potential. These qualities make it a suitable autogenous graft. A technique utilizing autogenous periosteal pedicle graft (PPG) for the treatment of gingival recession defects is described.

METHODS

Four patients with Miller Class I and II recessions > or = 3 mm were treated utilizing PPG.

RESULTS

At the end of one year, all defects were completely covered.

CONCLUSIONS

The PPG technique can be used for the treatment of gingival recession defects successfully.

A calcitonin receptor (CALCR) single nucleotide polymorphism is associated with growth performance and bone integrity in response to dietary phosphorus deficiency

Although concerns over the environmental impact of excess P in the excreta from pig production and governmental regulations have driven research toward reducing dietary supplementation of P to swine diets for over a decade, recent dramatic increases in feed costs have further motivated researchers to identify means to further reduce dietary P supplementation. We have demonstrated that genetic background impacts P utilization in young pigs and have identified genetic polymorphisms in several target genes related to mineral utilization. In this study, we examined the impact of a SNP in the calcitonin receptor gene (CALCR) on P utilization in growing pigs. In Exp. 1, 36 gilts representing the 3 genotypes identified by this CALCR SNP (11, 12, and 22) were fed a P-adequate (PA) or a marginally P-deficient (approximately 20% less available P; PD) diet for 14 wk. As expected, P deficiency reduced plasma P concentration, bone strength, and mineral content (P < 0.05). However, the dietary P deficiency was mild enough to not affect the growth performance of these pigs. A genotype x dietary P interaction (P < 0.05) was observed in measures of bone integrity and mineral content, with the greatest reduction in bone strength and mineral content due to dietary P deficiency being associated with the allele 1. In Exp. 2, 168 pigs from a control line and low residual feed intake (RFI) line were genotyped for the CALCR SNP and fed a PA diet. As expected, pigs from the low RFI line consumed less feed but also gained less BW when compared with the control line (P < 0.05). Although ADFI did not differ between genotypes, pigs having the 11 genotype gained less BW (P < 0.05) than pigs having the 12 or 22 genotypes. Pigs of the 11 and 12 genotypes had bones that tolerated greater load when compared with animals having the 22 genotype (P < 0.05). A similar trend was observed in bone modulus and ash % (P < 0.10). These data are supportive of the association of this CALCR SNP with bone integrity and its response to dietary P restriction. Although the allele 1 is associated with greater bone integrity and mineral content during adequate P nutrition, it is also associated with the greatest loss in bone integrity and mineral content in response to dietary P restriction. Understanding the underlying genetic mechanisms that regulate P utilization may lead to novel strategies to produce more environmentally friendly pigs.

Amplification of RUNX1 gene in two new cases of childhood B-cell precursor acute lymphoblastic leukemia: A case report

e21000

Background: Chromosome abnormalities of leukemia cells have important prognostic significance in childhood acute lymphoblastic leukemia (ALL). B-cell precursor acute lymphoblastic leukemia (BCP-ALL) ETV6/RUNX1 (alias TEL/AML1) is most frequent i.e. 15 - 35% in the children with 2 - 18 age group. We report two new cases with Pre B- cell ALL without ETV6/RUNX1 rearrangement, showing amplification of AML1 gene detected by FISH analysis. Methods: Bone marrow samples were analyzed for chromosomal abnormalities with conventional G-banding techniques and interphase fluorescence in situ hybridization (FISH) using probes to detect BCR/ABL t(9;22)(q34-q11) fusion, cryptic TEL/AML1 t(12:21)(p13-q22) and MLL rearrangement for del 11q23. Results: In first case a 3-year girl with four copies of AML (RUNX1) gene were observed in 95% of the cell with normal two copies of TEL (ETV6) gene in both interphase and metaphase FISH. We observed BCR-ABL negative translocation and no MLL gene rearrangement in all the interphase cells after doing FISH. We got a normal 46XX karyotype from bone marrow with conventional cytogenetics (CC) in the same patient. In second case, a 4-year male we observed four copies of AML and two copies of TEL gene in more than 80% of cells. In this patient, we got BCR-ABL negative translocation and three copies of MLL gene without any rearrangement through FISH. We got normal 46XY karyotype in the same patient through CC. Conclusions: In both the patients, we observed hyperdiploidy detected with four copies of RUNX1 gene showing tetrasomy of chromosome 21 detected with metaphase FISH analysis whereas G-banding shows normal diploidy. Bone marrow karyotype in combination with molecular cytogenetic techniques like FISH should be done for improvement in sensitivity and accurate cytogenetic analysis in childhood ALL patients for proper identification of prognostic group for optimum treatment. This is one of the few reported studies worldwide for amplification of RUNX1 gene from Indian subcontinent in childhood BCP-ALL.

No significant financial relationships to disclose.

A novel stone retrieval basket for more efficient lithotripsy procedures

This paper presents the development of an improved stone retrieval device that uses a newly designed cage of Nitinol wires encompassing a mesh basket made of a material that is laser resistant. Current methods to extract large stones involve imaging, using a laser to fragment the stones and then using existing cage-like baskets to trap the fragments individually and extracting them one at a time. These procedures are tedious, and may result in leaving some fragments behind that can reform causing the need for another procedure. The device presented in this paper will have a mesh-like sack which will consist of a laser resistant material of polytetrafluoroethylene (PTFE) enclosed within a newly designed Nitinol cage. Two alternate designs are provided for the cage in this paper. The handle of the device is revised to allow for a 3 Fr (1 mm) opening such that a laser's fiber optic cable can enter the device. Using this device a laser can be used to fragment the stone, and all the fragments are retained in the basket in both the design options. The basket can then be retracted allowing for the retrieval of all the fragments in one shot. The stone retrieval basket presented in this paper will significantly improve the efficiency and effectiveness of lithotripsy procedures for removal of large kidney and biliary tract stones.

Multifunctional catheters combining intracardiac ultrasound imaging and electrophysiology sensing

A family of 3 multifunctional intracardiac imaging and electrophysiology (EP) mapping catheters has been in development to help guide diagnostic and therapeutic intracardiac EP procedures. The catheter tip on the first device includes a 7.5 MHz, 64-element, side-looking phased array for high resolution sector scanning. The second device is a forward-looking catheter with a 24-element 14 MHz phased array. Both of these catheters operate on a commercial imaging system with standard software. Multiple EP mapping sensors were mounted as ring electrodes near the arrays for electrocardiographic synchronization of ultrasound images and used for unique integration with EP mapping technologies. To help establish the catheters' ability for integration with EP interventional procedures, tests were performed in vivo in a porcine animal model to demonstrate both useful intracardiac echocardiographic (ICE) visualization and simultaneous 3-D positional information using integrated electroanatomical mapping techniques. The catheters also performed well in high frame rate imaging, color flow imaging, and strain rate imaging of atrial and ventricular structures. The companion paper of this work discusses the catheter design of the side-looking catheter with special attention to acoustic lens design. The third device in development is a 10 MHz forward-looking ring array that is to be mounted at the distal tip of a 9F catheter to permit use of the available catheter lumen for adjunctive therapy tools.

Response to dietary phosphorus deficiency is affected by genetic background in growing pigs

Concern over the environmental effect of P excretion from pig production has led to reduced dietary P supplementation. To examine how genetics influence P utilization, 94 gilts sired by 2 genetic lines (PIC337 and PIC280) were housed individually and fed either a P-adequate diet (PA) or a 20% P-deficient diet (PD) for 14 wk. Initially and monthly, blood samples were collected and BW recorded after an overnight fast. Growth performance and plasma indicators of P status were determined monthly. At the end of the trial, carcass traits, meat quality, bone strength, and ash percentage were determined. Pigs fed the PD diet had decreased (P < 0.05) plasma P concentrations and poorer G:F (P < 0.05) over the length of the trial. After 4 wk on trial, pigs fed the PD diet had increased (P < 0.05) plasma 1,25(OH)(2)D(3) and decreased (P < 0.05) plasma parathyroid hormone compared with those fed the PA diet. At the end of the trial, pigs fed the PD diet had decreased (P < 0.05) BW, HCW, and percentage fat-free lean and tended to have decreased LM area (P = 0.06) and marbling (P = 0.09) and greater (P = 0.12) 10th-rib backfat than pigs fed the PA diet. Additionally, animals fed the PD diet had weaker bones and also decreased (P < 0.05) ash percentage and increased (P < 0.05) concentrations of 1alpha-hydroxylase and parathyroid hormone receptor mRNA in kidney tissue. Regardless of dietary treatment, PIC337-sired pigs consumed more feed and gained more BW than their PIC280-sired counterparts (P < 0.05) during the study. The PIC337-sired pigs also had greater (P < 0.05) HCW, larger (P < 0.01) LM area, and tended to have (P = 0.07) greater dressing percentage. Meat from the PIC337-sired pigs also tended to have greater (P = 0.12) concentrations of lactate but decreased (P = 0.07) concentrations of total glucose units 24 h postslaughter. Although plasma 1,25(OH)(2)D(3) concentrations were elevated (P < 0.05) in all the animals fed the PD diet, this elevation due to P deficiency tended (P = 0.09) to be greater in the PIC337-sired pigs after 12 wk on the treatment. The PIC337-sired pigs had stronger (P < 0.01) bones with greater ash percentage than the PIC280-sired pigs. The difference in the strength of the radii between the PIC337-sired pigs fed the PA and PD diets was greater than their PIC280-sired counterparts, which resulted in sire line x treatment interactions (P < 0.05). These data indicate differing mechanisms of P utilization between these genetic lines. Elucidating these mechanisms may lead to strategies to increase efficiency of growth in a more environmentally friendly manner.

A lumped-parameter model to investigate the effect of plantar pressure on arterial blood flow in a diabetic foot

This paper presents a lumped-parameter model for the big-toe region that investigates the effect of plantar pressure on the diameter of the blood vessels, specifically the arteries, in the presence of arterial and/or tissue changes. The model developed in this paper uses a multi-domain energy system approach to develop the lumped-parameter differential equations. Blood flow is modelled as fluidic flow through compliant pipes that have inertia, stiffness, and damping. The tissue material is treated as a soft compliant material that transmits the external force to the blood vessels. Conclusions have been drawn to show the effect of plantar pressure, tissue damage, and their combination on the diameter of the blood vessels. The principles used here can be used to model the entire foot and the model used to investigate the effect of plantar pressure, tissue damage, and arterial changes on different parts of the foot. The work presented here may also have applications in other vascular diseases.

Pediatric salivary gland neoplasms: The M. D. Anderson Cancer Center experience

20006

Background: Epithelial salivary gland neoplasms (ESGN) are uncommon tumors that mainly occur in adults, only 5 percent of ESGNs occur in children. Data regarding differences in clinical presentation and biologic behavior of these tumors between adult and pediatric patients remain unclear. There is less data concerning the role of radiation therapy in the treatment of ESGNs in pediatric patients. Methods: Retrospective review of medical records of patients presenting under age 18 years from January 1988 to August 2006. Results: 45 patients were evaluable. 26 patients were female. Median age at diagnosis was 14.7 years. Mucoepidermoid carcinoma (MEC) was seen in 22 cases (49%), acinic cell carcinoma 10 cases (22%), adenocystic carcinoma (ACC) 8 cases, and pleomorphic adenoma (PA) 5 cases. The parotid area was the most common involved site (25/45; 56%) with MEC and acinic cell noted in 80% of parotid cases. 76% of MEC cases (16/21) were grade 2 or 3 tumors. Initial complete resection was achieved in 20 ESGN cases, while the remaining cases required re-excision or adjuvant therapy. Thirteen patients received postoperative radiation. Median age was 15.8 years. Radiation therapy was used in 6 ACC cases, 4 MEC and 3 adenoid cystic. Primary site and first echelon nodes dose range was 54–64 Gy, and supraclavicular dose was 50 Gy in those in whom regional nodes were treated. Positive margin status and local invasion (perineural, lymphatic, or nodal) were the most common indications. Mean follow-up for 35 patients was 60.3 months (2–175 months). Nine patients were lost to follow- up, and one patient received therapy at another institution. Two patients died from progressive disease, and both had received radiation therapy. Conclusions: MEC is the most common ESGN in pediatrics, and the parotid is the most common involved site. Complete surgical resection remains the treatment of choice. Radiation therapy may be used as adjuvant therapy, but more study is required.

No significant financial relationships to disclose.

Spinal myxopapillary ependymoma outcomes in patients treated with surgery and radiotherapy at M. D. Anderson Cancer Center

1547

Background: Myxopapillary ependymomas (MPEs) are a distinctive variant of ependymomas both clinicopathologically and genetically. These tumors usually occur in the lumbosacral/cauda equina region. Most spinal ependymoma series published in the literature included a few patients with MPEs. In this study, we report the outcomes from a single institutional experience with 35 spinal MPEs treated with either surgery alone or with adjuvant radiotherapy (RT). Methods: The medical records of 35 patients with MPE treated at The University of Texas M. D. Anderson Cancer Center between December 1968 and July 2002 were reviewed. The median age of patients in this series was 35 years (range, 14–63 years) and the male to female ratio was 2.5:1. Twenty-one patients (60%) underwent a gross total resection, 13 (37%) a subtotal resection, and 1 (3%) a biopsy only; 22 of these patients (63%) also received adjuvant RT. The endpoints analyzed were progression-free survival, overall survival, and local control. Results: The median follow-up was 10.7 years. The 10-year OS, PFS and LC rates for the entire group were 97%, 62%, and 72% respectively. Twelve patients (34%) had disease recurrence, all in the neural axis; 8 patients had treatment failure at the primary site only, 3 in the distant neural axis only, and 1 at the primary site and in the distant neural axis. Older patient age (≤35 vs. >35 years; p=0.002) and initial treatment modality (surgery vs. surgery + adjuvant RT; p=0.04) showed significant impact on PFS. Conclusions: The long-term patient survival duration for MPE managed with surgery and adjuvant RT is favorable. Regardless of the extent of resection adjuvant RT appears to significantly reduce the rate of tumor progression. Failures in this series occurred exclusively in the neural axis, mainly at the primary site.

No significant financial relationships to disclose.

Total body irradiation, fludarabine, melphalan, and allogeneic hematopoietic stem cell transplantation for advanced pediatric hematologic malignancies

We evaluated the efficacy and toxicity of adding 9 Gy of total body irradiation (TBI), in three single daily fractions of 3 Gy, to the reduced intensity regimen of fludarabine 30 mg/m2 i.v. x 4 days and melphalan 140 mg/m2 i.v. x 1 day in advanced pediatric hematologic malignancies. Twenty-two acute lymphoblastic leukemia (ALL), six acute myeloid leukemia (AML), and one non-Hodgkin lymphoma patients were transplanted. Of these, 13 were beyond second remission, and five had prior hematopoietic stem cell transplant (HSCT). Twenty-one donors were unrelated, of which 19 were from cord blood (CB) units. Three of the eight related donors were genotypically disparate. Oral mucositis and diarrhea were the most common toxicities. Twenty-seven patients achieved neutrophil engraftment (median 16 days), and 23 had platelet engraftment (median 42 days). One patient had primary graft failure. Seven patients died of non-relapse causes in the first 100 days. With a median follow-up of 52 months, seven of 22 ALL, five of six AML, and one of one lymphoma patients are alive and in remission. The regimen of TBI, fludarabine, and melphalan allows the engraftment of allogeneic hematopoietic stem cells (including mismatched CB). It was fairly well tolerated in pediatric patients, even for second transplants. Its efficacy requires further evaluation.

Osteoarthritis

Osteoarthritis (OA) is a chronic degenerative disorder of multifactorial etiology characterized by loss of articular cartilage and periarticular bone remodelling. OA causes joint pain, typically worse with weight-bearing and activity as well as can manifest with stiffness after inactivity. It can present as localized, generalized or as erosive osteoarthritis. Primary osteoarthritis is mostly related to aging, whereas, secondary osteoarthritis is caused by another disease or condition. X-rays, arthrocentesis and arthroscopy remain the main diagnostic tools. Blood tests are performed to exclude diseases that can cause secondary osteoarthritis. The treatment of osteoarthritis includes non-pharmacological management, pharmacological treatment in the form of drugs which can modify symptoms, symptomatic slow acting drugs for OA or structure modifying OA drugs depending upon the clinical requirement of the patient. Patients with persistent pain and progressive limitation of daily activities despite medical management may be the candidates for surgery.

Phenotypic and functional characterisation of follicle-associated epithelium of rectal lymphoid tissue

Lymphoid follicles cluster in the terminal rectum of various animal species and of man and hence this site may be important in the development of immune responses to pathogens. For the induction of immune responses at mucosal sites, interplay is required between various cell types performing functions ranging from antigen-sampling cells via antigen-presenting cells to antigen-specific lymphocytes. Therefore, we have characterised the cell populations and relevant functioning of follicle-associated epithelium (FAE) and associated follicles in the terminal portion of rectum in cattle as a representative mammal. Immunohistochemical studies of this region identified immune cell subsets (CD4+, CD8+, WC 1+gammadelta, CD2+, CD 21+ and CD 40+ cells) characteristic of an immune-inductive site. Examination of FAE identified a subset of cells with structural and functional features of antigen-sampling M-cells. Cells of the FAE and adjacent follicle-associated crypts expressed vimentin and a subset of these cells internalised microparticles, a further attribute of M-cells. The FAE cells were phenotypically heterogeneous and therefore the function and phenotype of these cell subsets requires further characterisation, particularly with respect to their potentially important role in the interaction of hosts with pathogens and the development of immune responses.

COX-2 selective nonsteroidal anti-inflammatory drugs: current status

Since, their introduction, COX (cyclooxygenase enzyme)-2 specific inhibitors have become a rapidly growing segment of the prescription drug market. Researchers have recently focused on the potentially lethal side effects associated with their. FDA has banned the use of nimesulide (hepatotoxic) in pediatric patients and rofecoxib (cardiovascular complications) in both adults and children. COX-2 inhibitors may decrease vascular prostacyclin production and may tip the balance in favour of prothrombotic eicosanoids (thromboxane A2) and lead to increased cardiovascular thrombotic events. COX-2 inhibitors can also result into increase blood pressure, macular eruptions, urticaria, pseudoporphyria, erythema multiforme, oedema, worsening of heart failure, fatal allergic vasculitis and aggravation of doxorubicin-mediated cardiac injury. The COX-2 enzyme is also involved in the development of many organ systems, and its inhibition may lead to various congenital defects in neonates. It has been reported that COX-2 inhibitors also interfere with implantation, hence their use should be avoided in sexually active women at risk of pregnancy. However, presently the choice of COX-2 selective inhibitors for a particular patient should be based upon their relative efficacy, toxicity, concomitant drug use, concurrent disease states, hepatic and renal function and relative cost.

A novel reduced intensity regimen for allogeneic hematopoietic stem cell transplantation associated with a reduced incidence of graft-versus-host disease

SUMMARY

In all, 55 patients at high risk or ineligible for a conventional allogeneic hematopoietic stem cell transplant (HSCT) received a regimen consisting of extracorporeal photopheresis, pentostatin, and reduced dose total body irradiation. The median age was 49 years (18-70 years); 44 received a sibling and 11 an unrelated HSCT; 44% were over the age of 50 years and 31% had undergone a prior HSCT. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine and methotrexate. Full donor chimerism was documented in 98% by day +100. The 1000-day nonrelapse mortality was 11%. The median follow-up is 502 days (154-1104 days). The 1- and 2-year overall survival (OS) and event-free survival (EFS) are 67, 58 and 55%, and 47%, respectively. Patients who had not received a prior HSCT or had less than three prior chemotherapy regimens had a 71% OS and 67% EFS at 1 year. Greater than grade II aGVHD developed in 9% and chronic GVHD (cGVHD) in 43%, and extensive in 12% and limited in 31%. Of the patients, 86% who engrafted had a disease response, 72% had complete and 14% partial responses. This novel reduced intensity preparative regimen was well tolerated and associated with a low incidence of transplant-related mortality and serious acute and cGVHD.

Experience with the Arndt paediatric bronchial blocker

Previously reported techniques for single lung ventilation in children have failed to provide consistent, single lung ventilation with relative ease and reliability. We report our experience with the use of a new device, the Arndt 5 French (Fr) paediatric endobronchial blocker, for single lung ventilation in a series of 24 children. We were able to achieve single lung ventilation in 23 of the 24 patients (aged 2-16 yr). Placement required approximately 5-15 min. Attempts at placement were aborted in one patient who was unable to tolerate even short periods of apnoea because of lung pathology. Although it has some limitations, our experience suggests that the paediatric bronchial blocker can be used as a consistent, safe method of single lung ventilation in most young children.

Novel missense mutation in the coagulation factor IX catalytic domain associated with severe haemophilia B--Factor IXDelhi

Factor IX is a vitamin K-dependent serine protease, which exists as a zymogen in the blood. On activation to factor IXa, by factor XIa or tissue factor-factor VIIa complex, it forms tenase complex with factor VIIIa, in the presence of Ca2+. This tenase complex enzymatically converts factor X to factor Xa, thereby bringing about the coagulation cascade. Mutations in factor IX gene have been shown to cause haemophilia B, which is inherited as an X-linked recessive disorder. Herein we report a novel missense mutation at the nucleotide position 30829-T > A in the exon 8 of factor IX gene. This transversion leads to the substitution of histidine 236 to glutamine. This resulting abnormal protein has been named factor IXDelhi. Molecular modelling was performed to predict the molecular pathology of this mutation. We predict that this change in the catalytic domain may affect the surface loop that accommodates Ca2+, thereby leading to severe bleeding disorder.

Inhibition of skin sphingosine synthesis: enhanced percutaneous permeation of 5-fluorouracil

The present study was designed to investigate the role of skin sphingosine inhibition in enhancing the transcutaneous permeation of 5-fluorouracil (5-FU), a hydrophilic drug, across rat skin. Ethanol-perturbation significantly reduced the sphingosine content as compared to that in normal skin until 24 h of perturbation (p < 0.05). To maintain the low content of sphingosine for a longer time, beta-chloroalanine (beta-CA), a selective inhibitor of serine palmitoyl transferase, was used for inhibiting the sphingosine synthesis in viable skin. Application of beta-CA (600 microg or 1200 microg/7 cm2) to viable skin perturbed with ethanol significantly reduced the sphingosine content until 48 h as compared to that in perturbed viable skin (p < 0.05). However, the sphingosine content in viable skin perturbed with ethanol and treated with lower doses (200 or 400 microg/7 cm2) of beta-CA, returned significantly close to that in ethanol-perturbed viable skin at 36 h (p < 0.05). Skin sphingosine synthesis inhibition efficacy of 1200 microg beta-CA was insignificantly different to that of 600 microg dose of beta-CA at 36 h or 48 h (p < 0.05). The systemic delivery of percutaneously applied 5-FU across ethanol-perturbed rat skin treated with either 600 microg or 1200 microg beta-CA was significantly greater as compared to that obtained after oral administration or after application of lower percutaneous doses of beta-CA (p < 0.05). Higher Cmax, MRT, AUC and maintenance of effective plasma concentration of 5-FU for 46 h was achieved by a single topical application of a formulation containing 5-FU and 600 microg beta-CA to ethanol-perturbed skin.

Severe pulmonary hypertension: a frequent complication of stem cell transplantation for malignant infantile osteopetrosis

This report describes eight infants who developed acute severe pulmonary arterial hypertension (PAH) at days -2 to +89 after allogeneic stem cell transplantation (SCT) for malignant infantile osteopetrosis (MIOP). They were taken from a total of 28 children (frequency 29%) transplanted for this disease at three institutions between 1996 and 2002. Typical presentations were acute dyspnoea, hypoxia and brady/tachycardia usually in the absence of fever, crepitations or other evidence of infection. Six patients (75%) required assisted ventilation and five (62%) died. There was clinical or pathological evidence of veno-occlusive disease (VOD) in three children, but absence of VOD in the remaining five suggests that a separate disease process may be responsible for the PAH. Responses to nitric oxide (NO), defibrotide (DF), nicardipine and steroids in varying combinations were disappointing. Three children showed sustained improvement after administration of epoprostenol (EP, prostacyclin) in conjunction with NO and/or DF and remain well and free of PAH 25, 31 and 32 months post-transplant. PAH must therefore be excluded in any child who becomes acutely breathless after SCT for osteopetrosis.