RADIATION THERAPY IN BREAST CANCER—A Preliminary Report on the Application of a Technique of the McWhirter Type

A modification of the radiation technique advocated by McWhirter was used in the treatment of 12 patients with carcinoma of the breast. On the basis of observations it is believed that the method has definite merit. It is believed that for patients who have had radical mastectomy, radiotherapy should be protracted over a period of more than three weeks.     

Contribution of P2X4 receptor in pain associated with rheumatoid arthritis: a review

Purinergic Signalling - Pain is the most common symptom reported by patients with rheumatoid arthritis (RA) even after the resolution of chronic joint inflammation. It is believed that...     

Metastatic cervical carcinoma to the thyroid gland: a case report and review of the literature

Although metastases within the thyroid gland are rare, they are not as infrequent as generally believed. Asymptomatic breast, lung, and renal cell carcinomas may metastasize to the thyroid. When they become symptomatic, diagnosis relies upon fine needle aspiration cytology. We report the case of a squamous cell cervical cancer that presented metastatic lesions to the thyroid gland four years after the initial diagnosis. The procedures used to confirm the diagnosis, stage, and subsequently manage the patient are described. We present both a review of the necessary clinical investigation and the therapeutic options open to these patients. We conclude that patients who present swelling or palpable nodules in the thyroid side and have a history of a previous malignancy must be considered for metastatic disease.     

On the dispersion index of a Markovian molecular clock

The number of nucleotide substitutions accumulated in a gene or in a lineage is an important random variable in the study of molecular evolution. Of particular interest is the ratio of the variance to the mean of that random variable, often known as the dispersion index. Because nucleotide substitution is most commonly modeled by a continuous-time four-state Markov chain, this paper provides a systematic method of computing the dispersion indices exhibited by a continuous-time four-state Markov chain. Using this method along with computer algebra and Monte Carlo simulation, this paper offers partially proven conjectures that were supported by thorough computer experiments. It is believed that the Tamura model, the equal-input model and the Takahata-Kimura model always exhibit dispersion indices less than 2. It is also believed that a general four-state model can be chosen to exhibit a dispersion index of any desired magnitude, although the chance of a randomly chosen such model exhibiting a dispersion index greater than 2 is as small as about 2%. Relevance of these findings to the neutral theory is discussed.     

Patterns of contraceptive pill taking in an inner city practice.

A total of 161 patients completed a questionnaire about their pattern of taking the oral contraceptive pill. Only 28% (45) of patients were taking the pill according to the manufacturer''s instructions, and in the event of the pill being missed only 26% of patients would use a sheath. A tenth of the patients believed that amenorrhoea always indicated pregnancy, but 35% believed that amenorrhoea was harmful to the body. This group did not differ in their pill taking from the remaining 65% of patients.     

Adrenal-cortical function in patients with medullary carcinoma of the thyroid and pheochromocytoma.

Medullary carcinoma of the thyroid (MCT) is reported to synthesize ACTH. This ACTH is believed to be responsible for the development of Cushing's syndrome in some patients with MCT. To determine the frequency of occurrence of adrenal cortical overactivity in patients with MCT, we measured plasma cortisol concentration and the urinary excretion of 17-hydroxycorticosteroids, 17-ketosteroids and urinary free cortisol in 22 patients with MCT and 7 patients with MCT plus pheochromocytomas. The patients with MCT and MCT plus pheochromocytoma had similar adrenal cortical function to age and sex matched normal subjects. We conclude that adrenal cortical function is usually normal in patients with MCT.     

The aboral pore of hydra: evidence that the digestive tract of hydra is a tube not a sac

The digestive tract of Bilateria is a tube with a mouth at one end and an anus at the other end. Radiata, that include the phylum Cnidaria, have a blind-sac form of digestive tract with only one opening. It has therefore been commonly believed that the evolution of the body plan from Radiata to Bilateria included the change of the digestive tract from a blind sac to a tube. In this study, we report that there is a very narrow opening at the aboral end of hydra termed the aboral pore. This confirms a classical finding by Kanajew (Zool Anz, 76:37-44, 1928), but we confirmed it in both asexually reproduced and sexually reproduced polyps, demonstrating that the aboral pore represents innate morphology. We also find that the opening coincides with the site where synthesis of an extracellular matrix-degrading enzyme, hydra matrix metalloprotease, is elevated suggesting that the pore is maintained by extracellular matrix degradation. Finally, we find that there is material transfer through the opening in both inward and outward directions. From these observations, we conclude that the digestive tract and the body plan of hydra is not a blind sac as formerly believed but is a tube with a tapered end.     

Echocardiographic analysis of a malfunctioning Davila-Sierra mitral valve

Although the Davila-Sierra mitral valve prosthesis was removed from the market nearly a decade ago, a number of patients still have this valve in place. We recently studied the echocardiographic features of a malfunctioning Davila-Sierra mitral valve prosthesis. Abnormalities that suggested improper functioning of the prosthesis included a markedly delayed poppet opening and an early diastolic hump believed to represent motion of the mitral annulus. Previously described echocardiographic indications of dys-function were not observed in our patient. We report the first known echocardiographic evaluation of a Davila-Sierra prosthesis.     

Effectiveness of remantadine in outpatients during a period of epidemic outbreaks of influenza A and B

Extensive clinical data demonstrate that the use of remantadine for the treatment of ambulant influenza patients during the epidemic of influenza, types A and B, proved to be effective, which was manifested by an essential increase in the number of complications, mainly in the respiratory organs, and by a reduced length of the disease. The positive result of the curative action of remantadine is believed to be connected with the simultaneous wide circulation of type A (H1N1) and (H3N2) influenza viruses.     

Natural occurrence of the mycotoxin penitrem a in moldy cream cheese

The occurrence of the mycotoxin penitrem A in refrigerated cream cheese that was involved in the intoxication of two dogs is described. Penitrem A and the fungus Penicillium crustosum were isolated from the cream cheese and identified. This is believed to be the first definitive case of the natural occurrence of penitrem A.     

Evaluation and Treatment of Osteoporosis in Patients with a Fragility Hip Fracture

ObjectiveTo determine whether patients with fragility hip fractures underwent assessment and treatment of osteoporosis during initial hospitalization or recommendations for such intervention were made to the primary care provider (PCP) at the time of hospital dismissal.MethodsA review of medical records of patients admitted with a low-impact hip fracture to the Royal University Hospital in Saskatoon, Saskatchewan, Canada, was performed to determine whether recommendations were made to evaluate for or treat osteoporosis. In addition, a questionnaire was sent to the orthopedic surgeons practicing at the hospital to help identify barriers to widespread diagnosis and treatment of osteoporosis in such patients.ResultsBetween January and December 2004, 174 patients with fragility hip fractures were admitted to the Royal University Hospital. The mean age of these patients was 82.5 ± 9.8 years. Evaluation for treatment of osteoporosis was recommended in only 9 patients (5%). We found no significant differences in the intervention rates between male and female patients, between patients with and those without a prior history of osteoporosis or fracture, between patients who were previously taking osteoporosis medications and those who were not, and between patients who were seen by a medical consultant and those who were not. Most orthopedic surgeons believed that they were primarily responsible for the surgical care of these patients, and because they did not see these patients in regular follow-up, the management of osteoporosis was considered the responsibility of the PCP.Conclusion: The results of this study indicate that only a small number of patients with fragility hip fractures receive appropriate evaluation or treatment for underlying osteoporosis either during initial hospitalization or at the time of dismissal from the hospital. In this study, most orthopedic surgeons believed that evaluation and treatment of osteoporosis were the responsibility of the PCP. Because these patients have an increased risk for future fractures, barriers to the diagnosis and treatment of osteoporosis need to be removed, and health-care professionals need to be educated about appropriate risk factor modification in these patients. (Endocr Pract. 2005;11:370-375)     

Bacillus subtilis chemotaxis: a deviation from the Escherichia coli paradigm

In Escherichia coli, chemotactic sensory transduction is believed to involve phosphoryl transfer for excitation, and changes in receptor methylation for adaptation. In Bacillus subtilis, changes in degree of receptor methylation do not bring about adaptation. Novel methylation reactions are believed to be involved in excitation in B. subtilis. The main chemotaxis proteins of E. coli--CheA, CheB, CheR, CheW and CheY--are present in B. subtilis but play somewhat different roles in the two organisms. Several unique chemotaxis proteins are also present in B. subtilis. Some of the properties of B. subtilis chemotaxis are also seen in Halobacterium halobium, suggesting that there may be a similar underlying mechanism that predates the evolutionary separation of the bacteria from the archaea and eucarya.     

In vitro modulation using a synthetic antioxidant of the stimulus-induced formation of cyclic AMP

The in vitro treatment of membranes isolated from different rat organs with a water-soluble synthetic antioxidant has resulted in the change of basal and stimulus-induced adenylate cyclase activity. It is believed that the antioxidant effect is realized rather at the level of signal transfer from activated receptor to adenylate cyclase than at the level of agonist-receptor interaction.     

Perfusion Lung Scans Provide a Guide to Which Patients With Apparent Primary Pulmonary Hypertension Merit Angiography

There is hesitancy, based on the perceived risk, to do pulmonary angiography in patients believed to have primary pulmonary hypertension. Yet pulmonary hypertension due to major-vessel, chronic thromboembolism mimics primary pulmonary hypertension clinically and on standard laboratory tests. Because thromboembolic pulmonary hypertension is potentially remediable by thromboendarterectomy and primary pulmonary hypertension is not, differentiating between these disorders is essential. Angiography is required in patients with thromboembolic pulmonary hypertension to define the anatomic location of the thrombi. In evaluating perfusion lung scans of 110 patients with pulmonary hypertension to determine whether the scan might provide a guide to selecting those patients who merit angiography, no segmentalsize perfusion defects were noted on the scans of 64 patients with primary pulmonary hypertension, whereas all 46 patients with thromboembolic hypertension had one or more defects that were segmental in size or larger. These data indicate that a perfusion lung scan should be done in patients with pulmonary hypertension of uncertain cause and that those with one or more segmental or larger defects merit pulmonary angiography before being diagnosed as having primary pulmonary hypertension.     

Confirmation of a double-hit model for the NF1 gene in benign neurofibromas.

Neurofibroma is a benign tumor that arises from small or large nerves. This neoplastic lesion is a common feature of neurofibromatosis type 1 (NF1), one of the most common autosomal dominant disorders. The NF1 gene codes for a protein called "neurofibromin." It possesses a region that shares a high homology with the family of GTPase-activating proteins, which are negative regulators of RAS function and thereby control cell growth and differentiation. The evidence points to the NF1 gene being a tumor-suppressor gene. NF1 patients also have an increased incidence of certain malignant tumors that are believed to follow the "two hit" hypothesis, with one allele constitutionally inactivated and the other somatically mutated. Recently, somatic loss of heterozygosity (LOH) has been described for neurofibromas, and mutations in both copies of the NF1 gene have been reported for a dermal neurofibroma. The aim of our study was the analysis of the NF1 locus in benign neurofibromas in NF1 patients. We performed LOH analysis on 60 neurofibromas belonging to 17 patients, 9 of them with family history of the disease and 8 of them sporadic. We have analyzed five intragenic NF1 markers and six extragenic markers, and we have found LOH in 25% of the neurofibromas (corresponding to 53% of the patients). In addition, we found that in the neurofibromas of patients from familial cases the deletions occurred in the allele that is not transmitted with the disease, indicating that both copies of the NF1 gene were inactivated in these tumors. Therefore, the recent reports mentioned above, together with our findings, strongly support the double inactivation of the NF1 gene in benign neurofibromas.     

The biological sense of cancer: a hypothesis

Background  

Most theories about cancer proposed during the last century share a common denominator: cancer is believed to be a biological nonsense for the organism in which it originates, since cancer cells are believed to be ones evading the rules that control normal cell proliferation and differentiation. In this essay, we have challenged this interpretation on the basis that, throughout the animal kingdom, cancer seems to arise only in injured organs and tissues that display lost or diminished regenerative ability.     

The diagnostic effectiveness of an immunoenzyme test system for determining diphtheria toxin antigens in the blood serum in a clinical laboratory trial

The data on the approbation of the diagnostic value of the enzyme immunoassay (EIA) system for the determination of diphtheria toxin in the blood sera of diphtheria patients and persons suspected for diphtheria are presented. The EIA system was prepared on the basis of F(ab)2 fractions of purified antidiphtheria antibodies. 240 serum samples from diphtheria and tonsillitis patients and from healthy persons were studied. Diphtheria toxin was determined in all patients with the toxic form of diphtheria and in 41.3% of patients with its localized forms. Blood was taken mainly of the first week of the disease. In healthy persons the results of EIA were negative. Thus, the trial of the assay system in a clinical laboratory showed its good diagnostic effectiveness. The use of this EIA system in medical practice is believed to be quite promising.     

Lowering β-Amyloid Levels Rescues Learning and Memory in a Down Syndrome Mouse Model

β-amyloid levels are elevated in Down syndrome (DS) patients throughout life and are believed to cause Alzheimer''s disease (AD) in adult members of this population. However, it is not known if β-amyloid contributes to intellectual disability in younger individuals. We used a γ-secretase inhibitor to lower β-amyloid levels in young mice that model DS. This treatment corrected learning deficits characteristic of these mice, suggesting that β-amyloid-lowering therapies might improve cognitive function in young DS patients.     

Toward a survey of somatic mutation of the NF1 gene in benign neurofibromas of patients with neurofibromatosis type 1

Neurofibromatosis type 1 (NF1), a common autosomal dominant disorder caused by mutations of the NF1 gene, is characterized by multiple neurofibromas, pigmentation anomalies, and a variety of other possible complications, including an increased risk of malignant neoplasias. Tumorigenesis in NF1 is believed to follow the two-hit hypothesis postulated for tumor-suppressor genes. Loss of heterozygosity (LOH) has been shown to occur in NF1-associated malignancies and in benign neurofibromas, but only few of the latter yielded a positive result. Here we describe a systematic approach of searching for somatic inactivation of the NF1 gene in neurofibromas. In the course of these studies, two new intragenic polymorphisms of the NF1 gene, a tetranucleotide repeat and a 21-bp duplication, could be identified. Three tumor-specific point mutations and two LOH events were detected among seven neurofibromas from four different NF1 patients. Our results suggest that small subtle mutations occur with similar frequency to that of LOH in benign neurofibromas and that somatic inactivation of the NF1 gene is a general event in these tumors. The spectrum of somatic mutations occurring in various tumors from individual NF1 patients may contribute to the understanding of variable expressivity of the NF1 phenotype.     

MYELOGRAPHY—Diagnostic Value in Lesions of the Lumbar Intervertebral Discs with a Variation in Technique

Myelography using pantopaque in greater than usual amount with a variation in technique, which is described, is believed to provide increased accuracy in differential diagnosis and precise localization of lesions in the lumbar spine. The need for multiple space exploration is eliminated and more detailed information concerning the size and shape of lesions is provided as compared to that secured by the use of 3 or 6 cc. of opaque medium and fluoroscopic examination alone. In 53 cases in which lumbar myelography was performed and the diagnosis verified or disproved at operation, there was a 5 per cent diagnostic error in 41 instances in which the method outlined was used, as compared with 17 per cent error in 12 cases in which only 3 or 6 cc. of radiopaque material and fluoroscopy alone were used. The accuracy of the procedure would appear to warrant its use in the evaluation of patients suspected of having abnormalities of the lumbar discs associated with nerve root compression.