Some diminutive colorectal polyps can be removed and discarded without pathological examination.

BACKGROUND AND STUDY AIMS: Pathological examination of colorectal polyps is useful if clinical management is affected (i. e. when invasive carcinoma is detected or postpolypectomy surveillance interval is guided). Our aim was to assess whether the pathological examination of some diminutive (measuring ≤ 5 mm) polyps can be omitted. PATIENTS AND METHODS: Consecutive patients undergoing a colonoscopy at Pasteur Hospital (Colmar, France) between January and August 2008 were included in this prospective study. Six senior gastroenterologists predicted the future surveillance interval without referring to the result of pathological examination. RESULTS: In all, 350 polyps from 175 patients were removed and analyzed. The endoscopist was able to predict the correct surveillance interval without referring to the result of pathological examination in 118 patients (67.4 %; 95 % confidence interval [CI] 60.5 - 74.4). The pathological examination of 18.4 % (95 % CI 13.7 - 23.1) of diminutive polyps either associated with a cancer or a polyp measuring ≥ 10 mm or removed in very old or frail patients could be omitted without any consequence for the patient. If diminutive polyps one or two in number were discarded without pathological examination in patients with a personal history of colorectal neoplasm, three patients out of 43 would have a 5-year instead of a 3-year surveillance interval. As a whole, if 44.1 % (95 % CI 38.0 - 50.1) of diminutive polyps were discarded, the surveillance interval would remain identical in 98.3 % (95 % CI 96.4 - 100) of patients. CONCLUSIONS: The pathological examination of up to 44 % of diminutive polyps (i. e. 33 % of all polyps), can be safely omitted. The pathological examination would be required only for those with suspicious gross appearance, those three or more in number, and those isolated one or two in number that are removed from people without personal history of colorectal neoplasm.

Localization and posttranslational modifications of otefin, a protein required for vesicle attachment to chromatin, during Drosophila melanogaster development.

Otefin is a peripheral protein of the inner nuclear membrane in Drosophila melanogaster. Here we show that during nuclear assembly in vitro, it is required for the attachment of membrane vesicles to chromatin. With the exception of sperm cells, otefin colocalizes with lamin Dm0 derivatives in situ and presumably in vivo and is present in all somatic cells examined during the different stages of Drosophila development. In the egg chamber, otefin accumulates in the cytoplasm, in the nuclear periphery, and within the nucleoplasm of the oocyte, in a pattern similar to that of lamin Dm0 derivatives. There is a relatively large nonnuclear pool of otefin present from stages 6 to 7 of egg chamber maturation through 6 to 8 h of embryonic development at 25 degrees C. In this pool, otefin is peripherally associated with a fraction containing the membrane vesicles. This association is biochemically different from the association of otefin with the nuclear envelope. Otefin is a phosphoprotein in vivo and is a substrate for in vitro phosphorylation by cdc2 kinase and cyclic AMP-dependent protein kinase. A major site for cdc2 kinase phosphorylation in vitro was mapped to serine 36 of otefin. Together, our data suggest an essential role for otefin in the assembly of the Drosophila nuclear envelope.

Interactions among Drosophila nuclear envelope proteins lamin, otefin, and YA.

The nuclear envelope plays many roles, including organizing nuclear structure and regulating nuclear events. Molecular associations of nuclear envelope proteins may contribute to the implementation of these functions. Lamin, otefin, and YA are the three Drosophila nuclear envelope proteins known in early embryos. We used the yeast two-hybrid system to explore the interactions between pairs of these proteins. The ubiquitous major lamina protein, lamin Dm, interacts with both otefin, a peripheral protein of the inner nuclear membrane, and YA, an essential, developmentally regulated protein of the nuclear lamina. In agreement with this interaction, lamin and otefin can be coimmunoprecipitated from the vesicle fraction of Drosophila embryos and colocalize in nuclear envelopes of Drosophila larval salivary gland nuclei. The two-hybrid system was further used to map the domains of interaction among lamin, otefin, and YA. Lamin's rod domain interacts with the complete otefin protein, with otefin's hydrophilic NH2-terminal domain, and with two different fragments derived from this domain. Analogous probing of the interaction between lamin and YA showed that the lamin rod and tail plus part of its head domain are needed for interaction with full-length YA in the two-hybrid system. YA's COOH-terminal region is necessary and sufficient for interaction with lamin. Our results suggest that interactions with lamin might mediate or stabilize the localization of otefin and YA in the nuclear lamina. They also suggest that the need for both otefin and lamin in mediating association of vesicles with chromatin might reflect the function of a protein complex that includes these two proteins.

Effect of truncated forms of the steroidogenic acute regulatory protein on intramitochondrial cholesterol transfer.

It has been proposed that the steroidogenic acute regulatory (StAR) protein controls hormone-stimulated steroid production by mediating cholesterol transfer to the mitochondrial inner membrane. This study was conducted to determine the effect of wild-type StAR and several modified forms of StAR on intramitochondrial cholesterol transfer. Forty-seven N-terminal or 28 C-terminal amino acids of the StAR protein were removed, and COS-1 cells were transfected with pCMV vector only, wild-type StAR, N-47, or the C-28 constructs. Lysates from the transfected COS-1 cells were then incubated with mitochondria from MA-10 mouse Leydig tumor cells that were preloaded with [3H]cholesterol. After incubation, mitochondria were collected and fractionated on sucrose gradients into outer membranes, inner membranes, and membrane contact sites, and [3H]cholesterol content was determined in each membrane fraction. Incubation of MA-10 mitochondria with wild-type StAR containing cell lysate resulted in a significant 34.9% increase in [3H]cholesterol content in contact sites and a significant 32.8% increase in inner mitochondrial membranes. Incubations with cell lysate containing N-47 StAR protein also resulted in a 16.4% increase in [3H]cholesterol in contact sites and a significant 26.1% increase in the inner membrane fraction. In contrast, incubation with the C-28 StAR protein had no effect on cholesterol transfer. The cholesterol-transferring activity of the N-47 truncation, in contrast to that of the C-28 mutant, was corroborated when COS-1 cells were cotransfected with F2 vector (containing cytochrome P450 side-chain cleavage enzyme, ferridoxin, and ferridoxin reductase) and either pCMV empty vector or the complementary DNAs of wild-type StAR, N-47 StAR, or C-28 StAR. Pregnenolone production was significantly increased in both wild-type and N-47-transfected cells, whereas that in C-28-transfected cells was similar to the control value. Finally, immunolocalization studies with confocal image and electron microscopy were performed to determine the cellular location of StAR and its truncated forms in transfected COS-1 cells. The results showed that wild-type and most of the C-28 StAR protein were imported into the mitochondria, whereas most of N-47 protein remained in the cytosol. These studies demonstrate a direct effect of StAR protein on cholesterol transfer to the inner mitochondrial membrane, that StAR need not enter the mitochondria to produce this transfer, and the importance of the C-terminus of StAR in this process.

Mechanical stress of the carotid artery at the early phase of spontaneous hypertension in rats.

Common carotid artery (CCA) hypertrophy has long been recognized in the neonatal period of development in spontaneously hypertensive rats (SHR), but the mean circumferential and shear stresses acting on the arterial wall have never been investigated in vivo. We investigated intra-arterial blood pressure in conscious rats, CCA diameter (echotracking techniques), blood flow velocity (pulsed Doppler), wall thickness (histomorphometry), and ganglionic blockade (hexamethonium) in Wistar rats and SHR at 5 and 12 weeks of age. During this interval, weight gain was identical in the strains, whereas the increase in wall thickness and blood pressure was greater in SHR. CCA diameter was identical at week 5 and increased similarly at week 12 in both strains. During ganglionic blockade, a larger diameter was observed in SHR at week 5 for the same BP level, whereas equivalent values were observed at week 12. Blood flow velocity decreased with age but to a significantly greater extent in SHR. Mean circumferential stress and shear stress index were identical in both strains at week 12. However, from weeks 5 to 12, mean circumferential stress increased with age similarly in both strains, whereas the age-related decrease in mean shear stress index was much greater in SHR than Wistar rats. Thus, despite a higher blood pressure, SHR exhibit the same carotid diameter as Wistar rats during early development. Because the kinetics of shear stress are different in both strains, altered flow-dilatation mechanisms, and possibly resulting endothelial dysfunction, may be involved in the diameter changes.

Immunoaffinity purification: basic principles and operational considerations.

Immunoaffinity purification has become an important technique in biotechnology. In this review the basic principles of immunoaffinity separations are described with respect to the stages of operation and potential application. The most commonly used support materials, activation procedures, and coupling chemistries are compared to one another for suitability in various applications. Individual operational steps for fixed bed immunoadsorbents including loading, washing, elution and regeneration are described in terms of both theory and practice. Factors influencing adsorbent stability are identified, and alternative operation and configuration strategies are discussed in light of their application to immunoaffinity systems.

Human serum carnosinase: characterization, distinction from cellular carnosinase, and activation by cadmium.

Human serum carnosinase was assayed using a simple and sensitive fluorometric method. Under optimum conditions, the average adult serum hydrolyzed 42 mu mol of carnosine per ml per hour, about 17 times the average activity reported in the literature. Cadmium was twice as effective as manganese as an activator of this enzyme. Serum carnosinase was found to be different in many respects from cellular carnosinase. For example, the serum isozyme hydrolyzed homocarnosine, whereas the cellular carnosinase did not. The apparent molecular weight of serum carnosinase was 160 000, while that of the cellular isozyme was 90 000. Although it has been reported that serum contains two molecular forms of carnosinase, only one form was detected using several electrophoretic methods and two ion exchange chromatography procedures. The concentration of serum carnosinase varied greatly between individuals. Little or no enzyme was detected in children below 10 months in age. Thereafter, the average concentration of carnosinase increased gradually to reach the adult range at age 13-15.

Fluoxetine in tricyclic refractory major depressive disorder.

Data regarding open-label treatment with fluoxetine following failure to respond to tricyclic antidepressants (TCAs) or intolerance of TCA side effects, suggest a response rate between 51.4% and 62.1%, depending on the definition of TCA refractoriness employed. Double-blind study of this issue would extend these findings. Fluoxetine is well tolerated in patients unable to tolerate TCAs. Within this population, more than 80% of patients unable to tolerate TCAs found fluoxetine acceptable. Fluoxetine, as an alternative to polypharmaceutical augmentation, may represent a logical choice as the next step in therapy for a patient who has initially been treated with a TCA and has proven refractory or intolerant.

[Vidarabine treatment of chronic active hepatitis associated with hepatitis B virus multiplication. A randomized multicenter study]. / Traitement par la vidarabine de l'hépatite chronique active associée à la multiplication du virus de l'hépatite B. Etude multicentrique randomisée.

A randomized controlled study of one course of vidarabin was carried out in 30 patients with HBs Ag, HBe Ag, DNAp, positive chronic active hepatitis: 15 patients were treated with vidarabin given intravenously (15 mg/kg/day for 7 days then 7.5 mg/kg/day for 14 days); the other 15 patients received a placebo for 21 days. During treatment, DNA polymerase activity fell dramatically in 13 treated patients and in no controls (p less than 0.001). Six months after inclusion, ALT normalization was observed in 40 p. 100 of the treated patients and 6 p. 100 of the controls (p less than 0.05), a decrease in inflammatory activity on liver biopsies was observed in 70 p. 100 of the treated patients and 20 p. 100 of the controls (p less than 0.05), a permanent lost of DNA polymerase and of HBe Ag occurred in 33 p. 100 and 13 p. 100 of the treated patients and 20 p. 100 and 7 p. 100 of the controls, respectively. In addition, a second course of vidarabin was administered to the 12 patients who were still HBe Ag positive 6 months after the first course. During the next 6 months, 8 patients lost DNA polymerase and 4 lost HBe Ag. Altogether, the final score of durable inhibition of HBV replication was 11/15 (73 p. 100) within one year. The above results demonstrate that one course of vidarabin can significantly improve ALT and liver inflammatory activity but the effect upon HBV replication is only transient. A second course does however increase efficacy on HBV replication without additional side effects.

[Primary signet ring adenocarcinoma ofa diverted neurogenic bladder]. / Adénocarcinome primitif à cellules en bague à chaton sur vessie neurologique exclue. A propos d'un cas.

Primary signet-ring cell carcinoma of urinary bladder is an uncommon primitive bladder tumor. We report the first case occurring on a diverted neurogenic bladder. Except of adenocarcinoma of urachal origin, about 60 cases have been reported to date. The histogenesis of these tumors remains controversial.

[Osteogenic cranial sarcoma in Paget's disease (author's transl)]. / Sarcome ostéogène crânien sur maladie de Paget.

Sarcomatous changes in Paget's disease are known to occur, but cranial localization with invasion of cerebral parenchyma is rarely seen. A case is reported of osteogenic sarcoma occurring during Paget's disease, which was diagnosed from neurological signs, and on which a complete anatomical study was made.

[Multiple Carcinomas. Results of 2 813 autopsies (author's transl)]. / Les cancers multiples. Résultats de 2 813 autopsies.

The presence of multiple primary malignant neoplasms has been proved pathologically in a total of 50 cases recorded during a 5 years period (1970-1974). The 50 patients represented an incidence of 5.4% among the 992 patients proved to have cancer during the same 5 years period. The multiple lesions were diagnosed simultaneously in half of the patients. Twenty six patients had consecutive neoplasms, the average interval between the first and the second cancer was 6.9 years.

Optical information processing characteristics of the microchannel spatial light modulator.

The microchannel spatial light modulator (MSLM) is a versatile, highly sensitive, and optically addressed modulator that is well suited for low-light level real-time optical information processing. The image processing operations that can be achieved with the MSLM include contrast reversal, contrast enhancement, edge enhancement, image addition and subtraction, analog and digital intensity level thresholding, and binary level logic operations such as AND, OR, EXCLUSIVE OR, and NOR. Several of these operations are demonstrated herein. Recent prototype MSLMs have exhibited a halfwave exposure of 2.2 nJ/cm(2), an optical information storage time of more than two months, and a framing rate of 40 Hz with full modulation depth (200 Hz with 20% modulation depth). The role of secondary electron emission in the operation of the MSLM is discussed, and design modifications that would yield a spatial resolution of ~10 cycles/mm at the 50% point on an MTF curve are proposed.

Corticosteroid-resistant pyoderma gangrenosum associated with Crohn's disease: rapid cure with infliximab.

A 41-year-old woman with Crohn's disease had a severe and rapidly extensive corticosteroid-resistant pyoderma gangrenosum (PG) of the leg. She had been treated 2 years previously with antibiotics and surgery for a similar lesion of the back of the hand which had been diagnosed as a fulminating infection. Infliximab 5 mg/kg was given at weeks 0, 5 and 9. A dramatic response was observed within 72 h with a favourable effect persisting for 4 weeks after each infliximab infusion. A complete healing was achieved at week 11. This case illustrates that (1). PG of the hand is frequently misdiagnosed as an infection and treated with inappropriate therapies; (2). infliximab may be an interesting alternative in corticosteroid-resistant PG associated with Crohn's disease.