Unconventional Field-Induced Spin Gap in an S=1/2 Chiral Staggered Chain.

We investigate the low-temperature magnetic properties of the molecule-based chiral spin chain [Cu(pym)(H_{2}O)_{4}]SiF_{6}·H_{2}O (pym=pyrimidine). Electron-spin resonance, magnetometry and heat capacity measurements reveal the presence of staggered g tensors, a rich low-temperature excitation spectrum, a staggered susceptibility, and a spin gap that opens on the application of a magnetic field. These phenomena are reminiscent of those previously observed in nonchiral staggered chains, which are explicable within the sine-Gordon quantum-field theory. In the present case, however, although the sine-Gordon model accounts well for the form of the temperature dependence of the heat capacity, the size of the gap and its measured linear field dependence do not fit with the sine-Gordon theory as it stands. We propose that the differences arise due to additional terms in the Hamiltonian resulting from the chiral structure of [Cu(pym)(H_{2}O)_{4}]SiF_{6}·H_{2}O, particularly a uniform Dzyaloshinskii-Moriya coupling and a fourfold periodic staggered field.

Clinical evaluation of an international static image-based telepathology service.

Telepathology is the use of telecommunications technology as a means to facilitate transfer of image-rich pathology data between remote locations for the purposes of diagnosis, education, and research. Although varying levels of technology exist to accomplish this task, static image--based systems are currently the most widely used around the world. Field selection and image quality have often been identified as major impediments to the successful use of static images for diagnostic telepathology. Between November 1994 and July 1999, the Armed Forces Institute of Pathology (AFIP) performed electronic consultation on over 1,250 static image--based cases, recording a clinically significant concordance rate of 97.3% between telepathology and final diagnosis (in cases in which follow-up material was available). For the same subset of cases, an absolute concordance rate of 73.7% was attained. A review of the case flow and construction of the AFIP telepathology system is presented, as well as factors that have an impact on the diagnostic accuracy of static image-based telepathology sytems in general.

Telehematopathology in a clinical consultative practice.

We studied a series of 60 telepathology cases sent in consultation to the Department of Hematopathology from January 1, 1995, through July 31, 2000. Cases from the United States and the world representing academic, private, military, and federal sectors were reviewed. Ninety percent of patients were adults (54 of 60), and male patients outnumbered female patients 2 to 1. Ages were from 1 to 79 years (mean, 42 years). Forty-three cases were lymph nodes (72%), 14 were bone marrow or peripheral blood (23%), and 3 were from other sites (5%). Twenty-seven of the consultant diagnoses were benign (27 of 60). Twenty-nine were malignant (non-Hodgkin lymphoma, Hodgkin disease, and "other malignancy" groups), and 4 were nondiagnostic. Glass slide/paraffin tissue blocks were available in only 35 (58%) of 60 cases. The concordance rate for diagnostic telehematopathology cases with subsequent glass slide/paraffin block follow-up was 91% (29 of 32 cases). The discordance rate was 9% (3 of 32). This finding shows a high degree of diagnostic accuracy for consultative telehematopathology. Of 118 images analyzed, 58 were considered very good/good (49%), 32 were poor/very poor (27%), and 28 were fair (24%). Poor images had suboptimal resolution, color, or technical quality of transmission, and most poor images were low-power images. Additional case problems included insufficient immunoperoxidase stain availability, selection, and labeling; transmitted field selection; specimen preparation and staining; presence or absence of accompanying clinical data; and availability of ancillary studies such as flow cytometric, cytogenetic, and molecular data. From this analysis, the following recommendations are offered. To optimize telehematopathology consultation, include any additional information that have a significant influence on the final consultant diagnosis. Include any pertinent clinical information, laboratory data, special stains, immunoperoxidase stains, and molecular data. Select representative and diagnostically significant low-power and high-power fields for an accurate diagnosis. Label every immunostain or special stain submitted. Always send glass slides and tissue blocks when requested by the consultant. Optimize telemedicine microscopy and computer equipment with appropriate technical expertise, training, and support. In conclusion, the field of telepathology offers an exciting and potentially powerful solution to the problem of national and global subspecialty consultation. Hematopathology is potentially well suited to this technologically advanced marriage of computer and Internet technologies with modern microscopy, molecular diagnostics, immunophenotypic profiling, and the consultant pathologist.

Characteristics of a telecytology consultation service.

Although numerous reports describe the application of remote video microscopy to pathologic diagnosis (telepathology), only a few address some of the special issues surrounding remote cytologic diagnosis (telecytology). These studies have generally suggested a high correlation between telecytologic diagnoses and those arising from direct examination of the glass slides, but factors affecting the clinical utility of routine cytologic diagnosis have not been examined. In this report, we describe our experience in telecytologic consultation on 99 cases seen at the Armed Forces Institute of Pathology between October 1995 and November 1999. The mean time between receipt of the telecytologic images and the contributor receipt of the faxed report was 9.9 hours (median, 5.13 hours). Using stringent criteria for agreement, we find fair to good (48%) concordance between the contributor's impression and the consultant's opinion. The concordance between the consultant's telecytologic diagnosis and the subsequent glass slide diagnosis is imperfect; in 8 (31%) of 26 cases in which the glass slide was sent after the telecytology consultation, a minor discrepancy between these diagnoses was found. No major discrepancies were found between the consultant's telecytologic and glass slide diagnoses.

Telecytology: intraobserver and interobserver reproducibility in the diagnosis of cervical-vaginal smears.

Telecytologic diagnosis of cervical-vaginal smears is potentially useful because it could allow more efficient use of cytopathologist resources and expertise. A pathologist in one location could, in principle, review cytotechnologists' findings using a video display hundreds or thousands of miles away. Currently, bandwidth restrictions limit practical implementation of such a system to review of fields that had been selected for review by the cytotechnologist. The purpose of our investigation was to evaluate how well this type of review correlates with a review in which the entire slide is available for examination by the pathologist. We prospectively selected 100 consecutive cervical-vaginal smears over an 11-day period in August 1999. For each smear, 4 to 12 fields containing abnormal cells from each slide were digitally imaged. Each of 3 pathologists reviewed all digitized images and all glass slides. Diagnoses based on selected digitized images were compared with those based on conventional pathologist review. The kappa statistic, a measure of chance-corrected agreement (reproducibility), was calculated in each setting. Overall, intraobserver and interobserver reproducibility of cervical-vaginal smear diagnoses is fair to excellent. The use of remote digital images for pathologist review did not introduce large (2-step) diagnostic disagreements. The disagreement between a pathologist's glass slide and digital diagnoses is less than that for different pathologists reviewing glass slides, although interobserver differences were even greater in the interpretation of digital images.

Effects of cyclocreatine in rat hepatocarcinogenesis model.

Cyclocreatine (CCr), a substrate analogue of creatine kinase (CK: EC 2.7.3.2.), exhibits anti-tumor activity in vitro and in vivo. We examined the effects of CCr on the hepatocarcinogenesis of F344 rats caused by treatment with diethylnitrosamine (DEN), partial hepatectomy (PH) or 2-acetylaminofluorene (2-AAF). The rats were given a single intraperitoneal injection of 200 mg of DEN per kg in 0.85% NaCl solution at four weeks of age. Two weeks later they were divided into two groups. One group was continuously fed a commercial powder diet containing 0.02% 2-AAF for 12 weeks and the other was continuously fed a commercial powder diet containing 1% CCr plus 0.02% 2-AAF for 12 weeks. A third group of rats as a control was given only a normal powder diet for 12 weeks. All the groups were subjected to a two-thirds partial hepatectomy (PH) at 3 weeks under avertin anesthesia. To elucidate the inhibitory effect of CCr on chemical induced hepatocarcinogenesis, we examined not only the distribution of glutathione-S-transferase placental form (GST-P) a marker used for tumorigenesis, but also the inhibition of the degree of apoptosis. The number (No./cm2) and area (mm2/cm2) of GST-P positive liver foci were significantly lower in the 2-AAF + CCr treated when compared to the group treated with 2-AAF only. Our data suggest that CCr inhibits the degrees of GST-P-positive cells and apoptosis and is active against hepatocarcinogenesis in rat models. This result points out the unique nature of an anticancer agent that inhibits progression of chemically induced hepatocarcinogenesis of rats.

Multiple congenital malformation in a Holstein calf.

A 10-day-old male Holstein dairy calf with orthopaedic abnormalities was unable to stand but was alert with a suckle reflex. At necropsy, the calf showed multiple defects, including partial agenesis of the left rib plate, deformed left scapula, shortened left humerus, agenesis of the left kidney, atresia ani and scoliosis. The cause of these anomalies could not be determined. This report is the first to describe partial agenesis of ribs in a calf.

Surgical treatment and long-term outcome of ferrets with bilateral adrenal tumors or adrenal hyperplasia: 56 cases (1994-1997).

OBJECTIVE: To determine signalment, clinical signs, concurrent diseases, response to surgical treatment, and long-term outcome of ferrets with bilateral adrenal tumors or adrenal hyperplasia. DESIGN: Retrospective study. ANIMALS: 56 ferrets with bilateral adrenal tumors or adrenal hyperplasia confirmed histologically following subtotal bilateral adrenalectomy. PROCEDURE: Medical records of all ferrets with bilateral adrenal tumors or hyperplasia examined between 1994 and 1997 were reviewed. Ferrets underwent a subtotal bilateral adrenalectomy or a unilateral adrenalectomy initially, followed by a unilateral subtotal adrenalectomy when tumors or hyperplasia later developed on the contralateral adrenal gland. A long-term follow-up of a minimum of 18 months after final adrenal gland surgery was obtained by examination of medical records and follow-up telephone conversations. RESULTS: Clinical signs of hyperadrenocorticism included bilaterally symmetric alopecia, return to male sexual behavior in castrated male ferrets, or swollen vulva in spayed female ferrets. Surgical treatment of bilateral adrenal disease by subtotal bilateral adrenalectomy (or unilateral adrenalectomy followed by contralateral unilateral subtotal adrenalectomy) was effective with a mortality rate of < 2%. Only 3 (5%) ferrets required glucocorticoid or mineralocorticoid replacement following subtotal bilateral adrenalectomy. Recurrence after bilateral adrenalectomy was 15% with a mean long-term follow-up period of 30 months. CONCLUSIONS AND CLINICAL RELEVANCE: Bilaterally symmetric alopecia, return to male sexual behavior in castrated male ferrets, or swollen vulva in spayed female ferrets are indicative of adrenal tumors or adrenal hyperplasia in ferrets. Surgical treatment of bilateral adrenal disease by subtotal bilateral adrenalectomy is effective, with a low rate of complications and postoperative recurrence rate.

Coronavirus-associated epizootic catarrhal enteritis in ferrets.

OBJECTIVE: To characterize clinical signs and lesions and identify the etiologic agent associated with epizootic catarrhal enteritis in domestic ferrets. DESIGN: Cross-sectional study. ANIMALS: 119 ferrets with epizootic diarrhea of presumed viral cause and 5 control ferrets. PROCEDURE: Clinical records and biopsy or necropsy specimens of ferrets with presumed epizootic catarrhal enteritis were reviewed. Immunohistochemical staining for coronavirus antigen was performed on paraffin-embedded tissues from approximately 10% of affected ferrets to identify viral antigen and determine its distribution. Transmission electron microscopy was performed on fecal samples and sections of jejunum. Virus isolation studies as well as immunofluorescent tests for other similar viruses were performed. RESULTS: Characteristic microscopic lesions consistent with intestinal coronavirus infection (vacuolar degeneration and necrosis of villus enterocytes; villus atrophy, fusion, and blunting; and lymphocytic enteritis) were consistently detected in affected ferrets. Coronavirus particles were identified in feces and jejunal enterocytes by use of transmission electron microscopy. Immunohistochemical staining of jejunal sections revealed coronavirus antigens. Antigen staining was not detected in healthy ferrets or ferrets with other gastrointestinal tract diseases. Virus isolation was unsuccessful, and other similar viruses were not detected. CONCLUSIONS AND CLINICAL RELEVANCE: Results strongly implicate a coronavirus as the causative agent of epizootic catarrhal enteritis in ferrets. Diagnosis may be made on the basis of a combination of historical, clinical, and microscopic findings.

Anterior vertical incremental facial growth: its effects in class II treatment.

The present study shed some light on the anterior incremental vertical growth rates of the face. Both girls' and boys' upper and lower faces were studied starting four years before the presence of the adductor sesamoid of the thumb and stopping two years after closure of the distal epiphysis of the second digit. Examples of the treatment of Class II, Division I mal-occlusions using orthopedic (cervical headgear) forces during the skeletal age period studied were shown. The reactions of vertical changes of the maxilla along with those of the mandible were demonstrated. The clinical responses of both maxilla and mandible should be predictable if skeletal age is used in treatment planning.

Oriented lateral temporomandibular joint laminagraphs. Symptomatic and nonsymptomatic joints compared.

Lateral temporomandibular joint laminagraphs are aligned with the condyle axis on the basis of a submental-vertex radiograph. Condyle positions in nonsymptomatic and symptomatic joints are compared, revealing a wide range in patients with temporomandibular joint and myofascial pain dysfunction syndromes, with significant differences from non-symptomatic patients.

Diagnosis and prevention of maxillary cuspid impaction.

Upper cuspid impaction is a serious problem that occurs with sufficient frequency to justify diagnosis and intervention as early as a dental age of 8 years. Screening consists of identifying patients who lack a normal cuspid bulge on palpation, with follow-up radiographic evaluation where indicated. Selective removal of deciduous cuspids is a suggested interceptive measure in Class I uncrowded malocclusions.

A longitudinal study of rest position and centric occlusion.

A fifteen-year longitudinal study of rest position and centric occlusion was done on sixteen dentulous subjects with random occlusions. In reviewing the literature the author could find no other investigation with this number of years interim. Records consisted of lateral cephalometric roentgenograms taken when the patient was in rest position and in centric occlusion. Rest position was determined by the patient saying "m" and swallowing, and electromyographically when the anterior belly of the digastric and the temporalis muscles elicited the electrical activity. Both linear and angular measurements were made. The figures from 1958, 1959, and 1960 were averaged and compared with the mean of those taken in 1973. Rest position was found to have a small range of stability in all subjects, while the vertical dimension of centric occlusion increased in ten subjects, decreased in two, and remained the same in four.

Anterior malocclusion and soft tissue profile related to sound production and self-concept.

The objective of this study was to relate self concept and sound production to skeletal malocclusion and soft tissue facial profiles. The sample group consisted of forty-seven subjects divided into two groups. One group of eleven was selected on the basis of not having malocclusions from patients seeking general dental care. The other group of thirty-six subjects was selected on the basis of presenting a malocclusion and was chosen from patients seeking orthodontic care. Both groups were between the ages of eleven and fifteen. The findings indicate a high degree of correlation for the following: 1. Upper lip tip and the lower lip tip with skeletal convexity at Point A. 2. Convexity at Point A and abnormalities in self concept and speech production.

The effect of bite plane use on terminal hinge axis location.

The effect of bite phase therapy on the location of hinge axis was observed and compared in a sample of normal subjects and a group of individuals with TMJ dysfunction. The normal group displayed a mean change of 1.0 mm with a range of 0.3 mm to 3.4 mm between bite plane use and its absence. The direction of change with bite plane use was anterior with a tendency for superior component. The same group utilized the bite plane a second time and the axis location was compared with the original determined with bite plane use. This procedure was done to test the reproducibility of hinge axis on normal subjects. The mean change between the two bite plane uses was .87 mm with a range of 0.0 mm to 3.0 mm. The symptomatic patients changed a mean of 1.46 mm with a range of 0.0 to 3.3 mm. The direction of change was definitely posterior following therapy with a strong tendency for a superior component. This study seems to emphasize the need for a relaxed and asymptomatic muscular pattern for individuals on whom occlusal adjustments are to be made. In the presence of erroneous maxillomandibular skeletal relationships inaccuracy is inherent for occlusal equilibration.

Therapeutics in ferrets.

The domestic ferret (Mustela putorius furo) continues to grow in popularity as a pet species in North America as well as many countries around the world. With this rapid growth comes an increased potential for small and exotic animal practitioners to expand their ferret clientele. This article reviews the commonly used therapeutics in ferrets, as well as the general principles and guidelines for their use.

Repeat cytoreductive surgery (CRS) for recurrent colorectal peritoneal metastases: yes or no?

PURPOSE: To clarify the role of repeat CRS for recurrent colorectal carcinoma (CRC) through: (i) Systematic review of the literature (ii) Analysis of survival outcomes in a prospective cohort. METHODS: (i) Pubmed and MEDLINE from 1980 to July 2013 searched using terms: colorectal carcinoma, peritonectomy, cytoreductive surgery, hyperthermic intraperitoneal chemotherapy (HIPEC), redo, repeat, and iterative. (ii) Kaplan-Meier Survival analysis of consecutive patients undergoing repeat CRS at St George Hospital between Jan 2000 and July 2013. RESULTS: (i) The search strategy yielded 309 articles, 5 meeting inclusion criteria, reporting on 91 patients. Median overall survival from first CRS ranged from 39 to 57.6 months with 3-yr survival of 50%, and 5-year survival of 30%. Median survival from second CRS was 20-months with 1-yr survivals of 72% and 66% and 2-year survivals of 50% and 44%. (ii) Repeat CRS performed on 18 patients found median survival from first CRS was 59 months, with 1, 3, and 5-year survival of 100%, 52% and 26% respectively. Median survival from repeat CRS was 22.6 months with 1, 2, and 3-year survival of 94%, 48% and 12% respectively. CONCLUSION: The current data on repeat CRS in CRC is relatively immature and more data is required before drawing clear conclusions. Patient selection should be on a case by case basis conducted through a MDT process with emphasis on surrogate markers for favourable outcomes.