Morphologic variation of the diaphragmatic crura: a correlation with pathologic processes of the esophageal hiatus?

The contributions of muscle fibers from the right and left diaphragmatic crura to the formation of the esophageal hiatus have been documented in several studies, none coming to a complete consensus on the number of anatomic variations or the prevalence of these variations in the human population. These variations may play a role in the pathogenicity of specific diseases that involve the esophageal hiatus, such as hiatal hernias. We examined a total of two hundred adult cadavers during 2000-2007. The variations in the diaphragmatic crura, particularly their muscular contributions to the formation of the esophageal hiatus, were grossly examined and revealed a bilateral occurrence of diaphragmatic crura in all 200 specimens. The results of the various morphological patterns of circumferential muscle fibers forming the esophageal hiatus were classified into six groups. The most common type (Type I, 45%) formed the esophageal hiatus from muscular contributions arising solely from the right crus. In Type II (20%) the esophageal hiatus was formed by muscular contributions from the right and left crura. In Type III (15%), the right and left muscular contributions arose from the right crus with an additional band from the left crus. Type IV (10%) showed that the right and left muscular contributions arose from the right crus, with two additional (anterior and posterior) bands arising from the left crus. Type V (5%) demonstrated the contributions arising solely from the left crus. In Type VI (5%) the right and left contributions originated from the left crus with two additional bands, one from the right crus and one from the left crus. These variations may play a role in the pathogenicity of specific diseases that involve the esophageal hiatus such as hiatal hernia, gastroesophageal reflux disease and Dunbar's syndrome.

Effects of ertiprotafib on hepatic cytochrome P450 and peroxisomal enzymes in rats and dogs, and in rat and human primary hepatocytes

Ertiprotafib (ERTI) significantly increased liver weights in male and female rats, and moderately increased liver weights in male dogs after treatment for 28 days. The present study tested the hypotheses that the organ weight increases were associated with peroxisome proliferation in rats and induction of hepatic enzymes in rats and dogs, and would have limited impacts on humans. At a dosage of 200 mg kg-1 day-1, CYP4A was induced by tenfold in male rats and 2.4-fold in female rats. In male rats, CYP2B was induced by 1.2-fold and CYP3A was induced by 1.7-fold. Palmitoyl CoA oxidase was induced by 5.1-fold in male rats and 2.9-fold in female rats; carnitine acetyltransferase was induced by 10.4-fold in male rats and 5.2-fold in female rats. CYP3A, CYP4A and peroxisomal enzymes were not induced in dogs at 150/200 mg kg-1 day-1. ERTI at 50 microM markedly induced the mRNA level of CYP4A by up to fivefold in rat hepatocytes, but not in human primary hepatocytes. In conclusion, the liver weight increases observed in rats treated with ERTI appears to be due to rodent-specific peroxisome proliferation and the substantial induction of CYP4A1. ERTI is not a potent P450 inducer in dogs or in human hepatocytes. Therefore, ERTI is not expected to exert any significant effects on hepatic drug-metabolizing enzymes in humans.

A case of May-Thurner syndrome

May-Thurner syndrome is a condition that results from narrowing of the left common iliac vein lumen due to pressure from the right common iliac artery as it crosses anterior to it. We describe a very rare case in which a previously asymptomatic patient presented with May-Thurner syndrome.

The clinical anatomy of the cephalic vein in the deltopectoral triangle

Identification and recognition of the cephalic vein in the deltopectoral triangle is of critical importance when considering emergency catheterization procedures. The aim of our study was to conduct a cadaveric study to access data regarding the topography and the distribution patterns of the cephalic vein as it relates to the deltopectoral triangle. One hundred formalin fixed cadavers were examined. The cephalic vein was found in 95% (190 right and left) specimens, while in the remaining 5% (10) the cephalic vein was absent. In 80% (152) of cases the cephalic vein was found emerging superficially in the lateral portion of the deltopectoral triangle. In 30% (52) of these 152 cases the cephalic vein received one tributary within the deltopectoral triangle, while in 70% (100) of the specimens it received two. In the remaining 20% (38) of cases the cephalic vein was located deep to the deltopectoral fascia and fat and did not emerge through the deltopectoral triangle but was identified medially to the coracobrachialis and inferior to the medial border of the deltoid. In addition, in 4 (0.2%) of the specimens the cephalic vein, after crossing the deltopectoral triangle, ascended anterior and superior to the clavicle to drain into the subclavian vein. In these specimens a collateral branch was observed to communicate between the cephalic and external jugular veins. In 65.2% (124) of the cases the cephalic vein traveled with the deltoid branch of the thoracoacromial trunk. The length of the cephalic vein within the deltopectoral triangle ranged from 3.5 cm to 8.2 cm with a mean of 4.8+/-0.7 cm. The morphometric analysis revealed a mean cephalic vein diameter of 0.8+/-0.1 cm with a range of 0.1 cm to 1.2 cm. The cephalic vein is relatively large and constant, usually allowing for easy cannulation.

The ansa cervicalis revisited

Recurrent laryngeal nerve paralysis represents a major complication in oesophageal cancer surgery. Nerve-muscle transplantation to the paraglottic space after resection of the recurrent laryngeal nerve with the ansa cervicalis (AC) has recently become the procedure of choice. The aim of this study was to investigate the anatomical variations of AC in order to avoid iatrogenic injuries and facilitate surgical procedures. We examined 100 adult human formalin-fixed cadavers. The ansa cervicalis showed a great degree of variation regarding origin and distribution. The origin of the superior root of AC was found to be superior to the digastric muscle in 92% of the cases. Its vertical descent was found to be superficial to the external carotid artery in 72% and superficial to the internal carotid artery in 28% of the specimens. The inferior root of AC was derived from the primary rami of C2 and C3 in 38%, from C2, C3 and C4 in 10%, from C3 in 40% and from C2 in 12% of the cases. The inferior root passed posterolaterally to the internal jugular vein in 74% and anteromedially in 26% of the cases. The roots of AC were long (70%) or short (30%), and the union between the two roots was situated inferior or superior to the omohyoid. Not only is knowledge of the anatomy of the ansa cervicalis important for nerve grafting procedures, but surgeons should be aware of AC and its relationships to the great vessels of the neck in order to avoid inadvertent injury during surgical procedures of the neck.

Immune reconstitution inflammatory syndrome associated with PML in AIDS: A treatable disorder

An HIV-1-infected patient with progressive multifocal leukoencephalopathy presented clinical deterioration and contrast-enhancing lesions on brain nuclear MR after the initiation of highly active antiretroviral therapy (HAART). Brain biopsy identified an inflammatory reaction compatible with immune reconstitution inflammatory syndrome. Treatment with corticosteroids and transient suppression of HAART led to marked neurologic improvement.

Identification of greater occipital nerve landmarks for the treatment of occipital neuralgia

Important structures involved in the pathogenesis of occipital headache include the aponeurotic attachments of the trapezius and semispinalis capitis muscles to the occipital bone. The greater occipital nerve (GON) can become entrapped as it passes through these aponeuroses, causing symptoms of occipital neuralgia. The aim of this study was to identify topographic landmarks for accurate identification of GON, which might facilitate its anaesthetic blockade. The course and distribution of GON and its relation to the aponeuroses of the trapezius and semispinalis capitis were examined in 100 formalin-fixed adult cadavers. In addition, the relative position of the nerve on a horizontal line between the external occipital protuberance and the mastoid process, as well as between the mastoid processes was measured. The greater occipital nerve was found bilaterally in all specimens. It was located at a mean distance of 3.8 cm (range 1.5-7.5 cm) lateral to a vertical line through the external occipital protuberance and the spinous processes of the cervical vertebrae 2-7. It was also located approximately 41% of the distance along the intermastoid line (medial to a mastoid process) and 22% of the distance between the external occipital protuberance and the mastoid process. The location of GON for anaesthesia or any other neurosurgical procedure has been established as one thumb's breadth lateral to the external occipital protuberance (2 cm laterally) and approximately at the base of the thumb nail (2 cm inferior). This is the first study proposing the use of landmarks in relation to anthropometric measurements. On the basis of these observations we propose a target zone for local anaesthetic injection that is based on easily identifiable landmarks and suggest that injection at this target point could be of benefit in the relief of occipital neuralgia.

Observations of differences in laterality imbalance of breast biopsies and breast disease between Caucasian and African American women

10781

Background: A number of published reports have indicated that the left breast is at greater risk of cancer than the right breast (laterality imbalance) in women of all ages. In addition, a woman’s left breast is usually larger than her right breast. In the Clinical Breast Care Project, more than 2400 subjects have been enrolled following HIPAA compliant, IRB approved protocols. Of these, 1200 have undergone a biopsy and completed demographic and pathological questionnaires. We investigated whether there is a laterality imbalance among the patients with respect to ethnicity, menopausal status or pathological diagnoses. Methods: Female patients with biopsies on only one breast whose pathological questionnaire was completed within 90 days of the demographical questionnaire were included in this analysis but patients who were surgically post-menopausal were excluded. Multiple biopsies on one breast for each woman were counted as one event. For statistical analysis, Pearson’s chi-square test in SPSS was used. Results: Of the 1200 patients, 708 (546 caucasian; CA and 172 African American; AA) satisfied the above criteria. Although the total number of biopsy events are essentially evenly distributed on either breast for either ethnicity, statistical analysis showed that post menopausal CA women have fewer biopsy events on the left breast (41%, n=264) than their pre-menopausal counterparts (52%, n = 282; p < 0.05); On the contrary, post-menopausal AA women have significantly more biopsy events on the left breast (62%, n=50) than their pre-menopausal counterparts (42%, n = 122; p = 0.02). Further analysis based on pathological diagnoses indicated that benign, pre-menopausal, AA patients have fewer events on the left breast (42%, n = 98) compared to CA (54%, n = 211; p < 0.05). Discussions: Despite the small sample size, the data nonetheless suggest that there are significant, menopausal status dependent, laterality imbalances of breast disease biopsy among CA and AA women. These differences await evaluation.

No significant financial relationships to disclose.

Identifying low-risk febrile neutropenic cancer patients in the West of Scotland

18592

Background: Febrile neutropenia (FN) is a potentially life threatening complication of chemotherapy. In-patient treatment using intravenous antibiotics reduces FN related mortality. However, most patients with FN are at low risk of complication. Identifying them could result in new strategies such as out-patient, oral antibiotic, based treatment resulting in improved quality of life and cost savings. The Multinational Association for Supportive Care in Cancer (MASCC) and the Talcott model were developed to identify such patients. Two randomised controlled trials have shown that oral antibiotics in low risk patients are safe and effective. However are such models appropriate in populations with a high incidence of co-morbidity such as the West of Scotland? This study reviews FN admissions to our cancer centre to determine the proportion of patients that would fall into a low risk group according to the MASCC and/or Talcott models and to identify other factors that might predict for low risk. Methods: Review of FN admissions between June–December 2002. Data included: patient demographics, MASCC score, Talcott group, co-morbidity, haematological and biochemical values, prior use of antibiotics and growth factors (GFs) and whether the fever resolved without serious medical complication (FRWMC). Results: 77 episodes of FN involving 68 patients. Mean age = 51 (range 16–79). 94% involved patients with solid malignancies. Commonest tumour type was breast (29%). Patients were classified as MASCC and Talcott low risk in 52% and 31% of episodes respectively. There was a significant association between low risk MASCC score and low risk Talcott score (χ2 28.665, d.f.3, p < 0.001). Low risk MASCC was associated with FRWMC (χ2 4.193, d.f.1, p < 0.05). Multiple logistic regression of risk factors showed that high bilirubin and low albumin were associated with a worse outcome. FN mortality rate was 7.8%. Conclusions: The use of clinical risk models to identify low risk patients can predict for an uncomplicated recovery in our patients. Bilirubin and albumin values at presentation added predicted value for low risk over and above the MASCC model. Future trials may validate this observation.

No significant financial relationships to disclose.

Functional relationship and gene ontology classification of breast cancer biomarkers

Breast cancer is a complex disease that still imposes a significant healthcare burden on women worldwide. The etiology of breast cancer is not known but significant advances have been made in the area of early detection and treatment. The advent of advanced molecular biology techniques, mapping of the human genome and availability of high throughput genomic and proteomic strategies opens up new opportunities and will potentially lead to the discovery of novel biomarkers for early detection and prognostication of breast cancer. Currently, many biomarkers, particularly the hormonal and epidermal growth factor receptors, are being utilized for breast cancer prognosis. Unfortunately, none of the biomarkers in use have sufficient diagnostic, prognostic and/or predictive power across all categories and stages of breast cancer. It is recognized that more useful information can be generated if tumors are interrogated with multiple markers. But choosing the right combination of biomarkers is challenging, because 1) multiple pathways are involved, 2) up to 62 genes and their protein products are potentially involved in breast cancer-related mechanisms and 3) the more markers evaluated, the more the time and cost involved. This review summarizes the current literature on selected biomarkers for breast cancer, discusses the functional relationships, and groups the selected genes based on a Gene Ontology classification.

The complete nucleotide sequence, genome organization, and specific detection of Beet mosaic virus

Beet mosaic virus (BtMV) was identified almost five decades ago but has not been fully characterized at the molecular level. In this study, we have determined for the first time the complete nucleotide sequence of BtMV genomic RNA and have developed a specific molecular means for its diagnosis. The viral genome of BtMV comprises 9591 nucleotides, excluding the 3' terminal poly (A) sequence, and contains a single open reading frame (ORF) that begins at nt 166 and terminates at nt 9423, encoding a single polyprotein of 3086 amino acid residues. A 3' untranslated region of 168 nucleotides follows the ORF. The deduced genome organization is typical for a member of the family Potyviridae and includes 10 proteins: P1, HC-Pro, P3, 6K1, CI, 6K2, NIa-VPg, NIa-Pro, NIb and coat protein (CP). Nine putative protease cleavage sites were predicted computationally and by analogy with genome arrangements of other potyviruses. Conserved sequence motifs of homologous proteins of other potyviruses were found in corresponding positions of BtMV. BtMV is a distinct species of the genus Potyvirus with the most closely related species being Peanut mottle virus ( approximately 55% amino acid identity). Based on the nucleotide sequence obtained, we have developed a virus-specific RT-PCR assay for accurate diagnosis and differentiation of BtMV.

p27 deregulation in breast cancer: prognostic significance and implications for therapy

p27 is a key regulator of G1-to-S phase progression. It prevents premature activation of cyclin E-cdk2 in G1 and promotes the assembly and activation of D-type cyclin-cdks. While the p27 gene is rarely mutated in human cancers, the action of p27 is impaired in breast and other human cancers through accelerated p27 proteolysis, sequestration by cyclin D-cdks, and by p27 mislocalization in tumor cell cytoplasm. Reduced p27 protein is strongly associated with high histopathologic tumor grade, reflecting a lack of tumor differentiation. Loss of p27 is also an indicator of poor patient outcome in a majority of breast cancer studies, including node negative disease. The broad application of p27 in the clinical evaluation of breast cancer prognosis will require a consensus on methods of tumor fixation, staining, and scoring. This review will focus on mechanisms of p27 regulation in normal cells and how deregulation of p27 may arise in breast and other human cancers. The prognostic significance of p27 in human breast cancer and the possible therapeutic implications of these findings will also be reviewed.

Late-onset cytomegalovirus-associated interstitial nephritis in a kidney transplant

Cytomegalovirus is the most important viral infection in kidney transplants, but rarely affects the allograft after the sixth month posttransplantation. We present a patient who developed renal failure eighteen months posttransplant; a kidney biopsy showed cytomegalovirus inclusions, acute tubular necrosis and mild interstitial nephritis. After intravenous ganciclovir, renal function transiently improved. Cytomegalovirus pp65 antigen was weekly reported as negative. One month later another biopsy was performed due to renal failure. The findings were consistent with tubular atrophy and severe interstitial nephritis. No cytomegalovirus cellular inclusions were found on histology, including immunohistochemical and polymerase chain reaction studies; pp65 antigen studies were persistently negative. Despite an attempt to recover renal function with steroid therapy, the patient restarted hemodialysis 20 months posttransplantation. This report suggests that cytomegalovirus should be considered as a late cause of kidney failure even in the absence of infection-related symptoms. The irreversible allograft damage can be caused despite the successful eradication of the virus with intravenous ganciclovir.

Educational outcomes and leadership to meet the needs of modern health care

If professionals are to be equipped better to meet the needs of modern health care systems and the standards of practice required, significant educational change is still required. Educational change requires leadership, and lack of educational leadership may have impeded change in the past. In practical terms standards refer to outcomes, and thus an outcome based approach to clinical education is advocated as the one most likely to provide an appropriate framework for organisational and system change. The provision of explicit statements of learning intent, an educational process enabling acquisition and demonstration of these, and criteria for ensuring their achievement are the key features of such a framework. The derivation of an appropriate outcome set should emphasise what the learners will be able to do following the learning experience, how they will subsequently approach these tasks, and what, as a professional, they will bring to their practice. Once defined, the learning outcomes should determine, in turn, the nature of the learning experience enabling their achievement and the assessment processes to certify that they have been met. Provision of the necessary educational environment requires an understanding of the close interrelationship between learning style, learning theory, and methods whereby active and deep learning may be fostered. If desired change is to prevail, a conducive educational culture which values learning as well as evaluation, review, and enhancement must be engendered. It is the responsibility of all who teach to foster such an environment and culture, for all practitioners involved in health care have a leadership role in education.

Educational outcomes and leadership to meet the needs of modern health care

If professionals are to be equipped better to meet the needs of modern health care systems and the standards of practice required, significant educational change is still required. Educational change requires leadership, and lack of educational leadership may have impeded change in the past. In practical terms standards refer to outcomes, and thus an outcome based approach to clinical education is advocated as the one most likely to provide an appropriate framework for organisational and system change. The provision of explicit statements of learning intent, an educational process enabling acquisition and demonstration of these, and criteria for ensuring their achievement are the key features of such a framework. The derivation of an appropriate outcome set should emphasise what the learners will be able to do following the learning experience, how they will subsequently approach these tasks, and what, as a professional, they will bring to their practice. Once defined, the learning outcomes should determine, in turn, the nature of the learning experience enabling their achievement and the assessment processes to certify that they have been met. Provision of the necessary educational environment requires an understanding of the close interrelationship between learning style, learning theory, and methods whereby active and deep learning may be fostered. If desired change is to prevail, a conducive educational culture which values learning as well as evaluation, review, and enhancement must be engendered. It is the responsibility of all who teach to foster such an environment and culture, for all practitioners involved in health care have a leadership role in education.

Iminosugars as possible broad spectrum anti hepatitis virus agents: the glucovirs and alkovirs

Glucosidases in the endoplasmic reticulum (ER) mediate the first step in processing N-linked oligosaccharides. Recent evidence suggests that morphogenesis and secretion of members of the hepatitis B and flavivirus families are more dependent on these enzymes than are most host glycoproteins. Thus, it is possible that glucosidase inhibitors can be designed that are safe and selective for the treatment of hepatitis B and possibly C (since hepatitis C virus is a member of the flavivirus family), making them broad spectrum with respect to hepatitis viruses. Numerous pharmacological and genetic dissections support the notion that glucosidase inhibition can have an antiviral effect, and imino sugars that competitively inhibit ER glucosidases have been proposed as anti-hepatitis drug candidates. We call this family of compounds 'glucovirs'. Recently, however, alkylated imino sugars that retain substantial antiviral activity but lack glucosidase inhibitory activity have been described. These compounds are called 'alkovirs' and their mechanism of action is unknown. This review considers the rationale of the glucovir and alkovir approach to the treatment of hepatitis B and C.

Diverse delayed effects in human lymphoblastoid cells surviving exposure to high-LET (56)Fe particles or low-LET (137)Cs gamma radiation

To obtain information on the origin of radiation-induced genomic instability, we characterized a total of 166 clones that survived exposure to (56)Fe particles or (137)Cs gamma radiation, isolated approximately 36 generations after exposure, along with their respective control clones. Cytogenetic aberrations, growth alterations, responses to a second irradiation, and mutant frequencies at the Na(+)/K(+) ATPase and thymidine kinase loci were determined. A greater percentage of clones that survived exposure to (56)Fe particles exhibited instability (defined as clones showing one or more outlying characteristics) than in the case of those that survived gamma irradiation. The phenotypes of the unstable clones that survived exposure to (56)Fe particles were also qualitatively different from those of the clones that survived gamma irradiation. A greater percentage (20%) of the unstable clones that survived gamma irradiation than those that survived exposure to (56)Fe particles (4%) showed an altered response to the second irradiation, while an increase in the percentage of clones that had an outlying frequency of ouabain-resistant and thymidine kinase mutants was more evident in the clones exposed to (56)Fe particles than in those exposed to gamma rays. Growth alterations and increases in dicentric chromosomes were found only in clones with more than one alteration. These results underscore the complex nature of genomic instability and the likelihood that radiation-induced genomic instability arises from different original events.

Characteristics of chromosome instability in the human lymphoblast cell line WTK1

The characteristics of spontaneous and radiation-induced chromosome instability were determined in each of 50 individual clones isolated from control populations of human lymphoblasts (WTK1), as well as from populations of these cells previously exposed to two different types of ionizing radiation, Fe-56 and Cs-137. The types of chromosome instability did not appear to change in clones surviving radiation exposure. Aneuploidy, polyploidy, chromosome dicentrics and translocations, and chromatid breaks and gaps were found in both control and irradiated clones. The primary effect of radiation exposure was to increase the number of cells within any one clone that had chromosome alterations. Chromosome instability was associated with telomere shortening and elevated levels of apoptosis. The results suggest that the proximal cause of chromosome instability is telomere shortening.