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At least 1,549 records · Page 86Linked to original sources
PubMed2003

Short androgen receptor allele length is a poor prognostic factor in epithelial ovarian carcinoma.

PURPOSE: Epidemiological evidence implicates a heightened androgenic state in women with epithelial ovarian cancer. Androgen activity may be modulated by altered expression or activity of the androgen receptor (AR) or AR polymorphisms. Exon 1 of the AR gene contains a polymorphic (CAG)(n) sequence whose length is inversely correlated with transcriptional activity. EXPERIMENTAL DESIGN: Differential expression of AR mRNA and protein was examined in 46 primary cultures of normal human ovarian surface epithelium (HOSE) and malignant Cedars-Sinai ovarian cancer (CSOC) ovarian epithelial cells. AR allele length was characterized by genotyping in 77 ovarian cancer specimens. RESULTS: AR mRNA expression was higher in CSOC primary cultures (1.58 +/- 0.17) when compared with HOSE (1 +/- 0.09, P = 0.005), but protein expression was not statistically different. CAG repeat lengths were shorter in CSOC (20.6 +/- 1.2) than in HOSE (23.4 +/- 0.9, P = 0.04). Patients with an AR allele containing < or =19 CAG repeats had a shorter time to recurrence (5.5 versus 19.4 months, P < 0.0001) and overall survival (9 versus 32.6 months, P = 0.0007). There was no correlation between AR allelotype and age of diagnosis, stage, or grade; however, a short CAG length < or =19 repeats was associated with decreased surgical cytoreducibility (44.4 versus 10.3%, P = 0.035). Multivariate analyses confirmed a short AR allele as an independent prognostic factor (P = 0.02). CONCLUSIONS: These data support epidemiological evidence linking heightened androgenicity to the pathogenesis and tumor biology of epithelial ovarian cancer.

Alleles↗
PubMed2004

Isolation of a promoter region of a secreted metalloprotease gene from Microsporum canis.

MEP3 of Microsporum canis encodes a 43.5 kDa extracellular keratinolytic metalloprotease, which is thought to be one of the virulence-related factors in dermatophytosis. In order to analyze the system underlying the regulation of MEP3 gene expression, the 5'-upstream region was isolated by inverse PCR. The nucleotide sequence of a DNA fragment of about 2.1 kb containing the coding region contains putative transcription factor binding sites and transcriptional initiation points. Further analyses of the regulatory sequence may be useful for understanding the molecular basis of the coordinated expression of the various genes involved in dermatophytosis.

Amino Acid Sequence↗
PubMed2005

Magnetic resonance imaging of pelvic and femoral bones for detection of bone marrow infiltration in patients with non-Hodgkins lymphoma.

OBJECTIVE: Detection of the residual bone marrow (BM) involvement is essential in treatment of patients with non-Hodgkin's lymphoma (NHL). Bilateral iliac crest BM biopsies appear to have low sensitivity for BM infiltration, while magnetic resonance imaging (MRI) presents more global view of BM. This study was conducted to determine the advantage of femoral marrow MRI as a non-invasive technique over bilateral iliac crest BM biopsies in detecting BM infiltration before treatment and residual disease after completion of treatment. METHODS: Over a period of 27 months from January 2002 to March 2004, a total of 30 patients with newly diagnosed NHL were included in the study. Magnetic resonance imaging of 26 patients were conducted in King Fahd Hospital of the University, Al-Khobar, Kingdom of Saudi Arabia. Magnetic resonance imaging of 4 patients were referred from different hospitals in the Eastern Province. Twenty-five patients were of B-cell type and 5 patients were of T-cell type. Coronal MRI of the pelvis and femoral marrow were obtained by the T1, T2-weighted spin echo sequences and short TI inversion recovery technique. RESULTS: Magnetic resonance images showed BM infiltration in 17 cases (56.7%) before treatment and positive biopsy results were found in 9 cases (30%); all had abnormal MR images. There was a significant difference between both methods in the detection of infiltration (p=0.037). Magnetic resonance imaging showed that 58.8% of cases have scattered pattern, 23.5% were uniform and 17.6% of cases have nodular patterns. Magnetic resonance images after completion of treatment showed residual BM infiltration in 6 out of 17 cases who previously had positive MR images and only one case of them had a positive BM biopsy with a significant difference between both methods and all of them relapsed within 6 months (p=0.034). CONCLUSION: Magnetic resonance images of the pelvis and femoral marrow were superior than BM biopsy on detection of BM infiltration before treatment and residual infiltration after treatment.

Adolescent↗
PubMed2005

[Karyotype and karyofund of chironomids Polypedilum (Pentapedilum) sordens (Diptera, Chironomidae)].

Karyotypes and karyofund of chironomids P. Polypedilum (Pentapedilum) sordens (Van der Wulp, 1874) from four water bodies of Saratov region have been analysed. 2n = 6, I (GAB) > II (CD) > III (EF). A cytophotochart of polytene chromosomes of this species was composed, and discovered inversions were identified on its base. The level of inversion polymorphism is high. There are 18 chromosome sequences in the karyofund. The frequency of heterozygote inversions is 1.6-2.5 per specimen. On the base of this cytochart it is possible to produce chromosome charts of other species of subgenus Pentapedilum.

Animals↗
PubMed1990

[Magnetic resonance imaging in optic nerve lesions with multiple sclerosis].

Magnetic resonance imaging (MRI) of the optic nerves was performed in 10 patients with multiple sclerosis (MS) using short inversion time inversion recovery (STIR) pulse sequences, and the results were compared with the visual evoked potentials (VEP). The 10 patients had optic neuritis in the chronic or remitting phase together with additional symptoms or signs allowing a diagnosis of clinically definite or probable MS. Sixteen optic nerves were clinically affected and 4 were unaffected. MRI was performed using a 0.5 tesla superconducting unit, and multiple continuous 5 mm coronal and axial STIR images were obtained. A lesion was judged to be present if a focal or diffuse area of increased signal intensity was detected in the optic nerve. In VEP, a delay in peak latency or no P 100 component was judged to be abnormal. With regard to the clinically affected optic nerves, MRI revealed a region of increased signal intensity in 14/16 (88%) and the VEP was abnormal in 16/16 (100%). In the clinically unaffected optic nerves, MRI revealed an increased signal intensity in 2/4 (50%). One of these nerves had an abnormal VEP and the other had a VEP latency at the upper limit of normal. The VEP was abnormal in 1/4 (25%). In the clinically affected optic nerves, the degree of loss of visual acuity was not associated with the longitudinal extent of the lesions shown by MRI. The mean length was 17.5 mm in optic nerves with a slight disturbance of visual acuity and 15.0 mm in nerves with severe visual loss.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMedDate not supplied

[Magnetic resonance in renal transplants].

The authors report their experience in the study of renal transplant recipients by MR, in order to determine its clinical potentials. The main purpose of this work is to focus on MR patterns in relation to clinical findings of rejected or normally functioning kidney. Twenty-four patients were examined with a 0.5 T superconductive magnet, body coil, spin-echo pulse sequence (SE) and inversion-recovery (IR). MRI patterns could be seen in normally functioning kidneys and transplant rejections, while variable MRI findings were observed in transplants with acute tubular necrosis (ATN). In the normally functioning transplanted kidney there is a clear corticomedullary differentiation (CMD), and the extent of vascular penetration into the renal parenchyma is clearly seen. In transplant rejection, CMD is either diminished or absent, and there is no vascular penetration into the parenchyma; to differentiate acute from chronic rejections, the increase/decrease in renal size and the change in renal shape (spherical shape in acute transplant rejection) respectively must be observed. MRI proves thus to be useful in the study of renal transplants, even in case of questionable clinical findings, and in patients in whom renal biopsy is contraindicated.

Adolescent↗
PubMed1995

[Effect of antisense oligonucleotides on myo-intimal hyperplasia in a model of abdominal aortic injury in the rat].

Restenosis at a rate > 30% at 6 months is the major complication of both coronary and peripheral arterial angioplasty. Restenosis is mainly due to proliferation of smooth muscle cells, extracellular matrix and collagen which form a neointima. The proto-oncogene c-myb is a gene with an immediate response which has been implicated in the proliferation and alteration of the phenotype of smooth muscle cells. The antisenses are molecules of single-helix DNA the sequence of which is inverse to that of messenger RNA of the target proto-oncogene. They therefore have the possibility of forming a double helix with the messenger RNA and of preventing its translation. The antisenses of c-myb have already been successfully tested in in vitro and in vivo models of neointimal proliferation. The aim of this study was to demonstrate the efficacy of c-myb antisenses on the proliferation of smooth muscle cells in a model of abdominal aortic injury in the rat. Thirty-five male Wistar rats with an average weight of 350 grams were operated. Smooth muscle cell proliferation was obtained by desendothelialisation of the abdominal aorta from the level of the left renal vein to the aortic bifurcation. Using a randomised, double-blind protocol, 17 rats were given 500 microliters of pluronic gel (control group), 9 a sense oligonucleotide of c-myb in 500 microliters of pluronic gel (sense group) and 9 a c-myb antisense oligonucleide in 500 microliters of pluronic gel (antisense group). Two rats were given fluorescinlabelled antisenses; one was sacrificed 4 hours and the other 24 hours later.(ABSTRACT TRUNCATED AT 250 WORDS)

Angioplasty↗
PubMedDate not supplied

Prominent white matter cavitation in an infant with Alexander's disease.

The clinical history and autopsy findings are reported on a case of infantile Alexander's disease (AD). The patient, a white baby girl, developed seizures at age 4 months accompanied by internal hydrocephalus. She died at age 11 months following a progressive, downhill course of profound psychomotor retardation, recurrent seizures and cachexia. The general autopsy was remarkable for cachexia. The formalin fixed brain and spinal cord were studied by light and electron microscopy (EM). The brain was normal in weight for age but showed diffuse pallor of white matter and marked cavitation involving the cerebral and cerebellar subcortical white matter, most profound in the frontal lobes. Microscopically the CNS showed classic features of AD with diffuse paucity of myelin and massive proliferation of astrocytes bearing Rosenthal fibers (RF). The latter appeared as granular osmiophilic deposits associated with 8-10 nm filaments within astrocytic processes and cell bodies by EM. This case of AD is remarkable for the extreme degree of cavitation. Cavitary changes affect up to one third of typical cases of AD and are invariably present in the frontal white matter. Affected patients are generally much younger and have a shorter clinical course than AD patients without brain cavitation. The dysmyelination of AD inversely parallels the temporal sequence of normal myelination and suggests a relative resistance of early myelinated structures to the presumed astrocytic defect causing AD. Adults with de novo formation of RF's in the CNS have a varied clinical and pathological appearance, rarely show brain cavitation and should probably be distinguished from classic AD in children.

Astrocytes↗
PubMed1994

[The role of magnetic resonance in characterizing focal liver lesions].

128 Magnetic resonance (MR) investigations of single or multifocal nodular liver lesions were retrospectively reviewed. All lesions had been identified, but not characterized, with ultrasonography (US). All the studies were performed with a 0.5-T superconductive magnet (Philips Gyroscan); spin-echo (SE) T1/proton density/T2-weighted and inversion recovery (IR) pulse sequences were used routinely. Characterization was attempted considering the following variables: a) lesion outline; b) the presence of some kind of capsular or pseudocapsular ring; c-d) homogeneity of signal intensity and its difference from surrounding liver parenchyma; e) possible central scar and its signal features; f) associated lesions (multifocal nodules, ascites, locoregional adenopathies, venous thrombosis). Diagnostic confirmation was obtained by means of biopsy (63 patients), of other imaging techniques (35 patients), or of clinical follow-up over 12 months at least (30 patients). Our results confirm high MR accuracy in the diagnosis of hemangioma (48/50 cases, 96% confidence) and even higher accuracy in focal fatty liver infiltration (9/9 cases, 100% confidence), thanks to some typical MR signal patterns on appropriate acquisition techniques--i.e., SE multiecho pulse sequences and IR sequences, respectively, with liver and fat signal nulling. Primary non-malignant focal liver lesions were identified mainly on a morphological basis (smooth roundish outline with/without capsular or pseudocapsular ring; central starlet scar; "basket" or "spoked wheel" patterns): these features allowed the correct identification of 5/7 focal nodular hyperplasia cases. On the other hand, in the absence of these typical morphological features and of specific MR signal changes, adenomas were misdiagnosed in all cases but one. The study of focal lesions in cirrhotic liver disease exhibited 66.6% confidence in the diagnosis of regenerating nodules, on the basis of their iso/hypointensity relative to liver on T2-weighted pulse sequences. Such a behavior seems to be due to intracellular iron loading, to small cell size and to thin vascular network, which are typical of cirrhotic regenerating areas. The diagnosis of hepatocellular carcinoma relies on both morphostructural features and possible associated lesions: in our series, 22/25 cases (88% confidence) were correctly identified. Indeed, this result was somehow influenced by the case history of the patients and by specific serologic indexes. Finally, MRI exhibited high sensitivity in the detection of focal liver involvement in neoplastic patients. However, the intrinsic range of variability and the lack of specificity of MR signal intensity, because of different histopathologic cell types, do not usually allow an unquestionable diagnosis to be made, especially for single lesions.

Biopsy↗
PubMed1996

Back-mutation of the V-Ets to the C-Ets carboxy-terminal amino acids in the P135gag-myb-ets results in chicken neuroretina cells transformation and loss of basic fibroblast growth factor responsiveness.

The v-Myb, v-Ets containing E26 retrovirus (called in this work E26ABC) induces the proliferation of chicken neuroretina (CNR) cells in minimal medium, strongly stimulated by basic Fibroblast Growth Factor (bFGF) which confers on them the ability to form colonies in soft agar. V-Ets differs from its cellular counterpart c-Ets-1 by two point mutations and by the replacement of the 13 last C-terminal amino acids by 16 unrelated residues as a consequence of DNA segment inversion in the viral sequence. It has been documented that this different C-terminal sequence influences DNA binding activity and specificity. Replacement in E26ABC virus of the sequence encoding the 16 v-Ets last C-terminal amino acids by the sequence encoding the 13 c-Ets-1 derived C-terminus (virus E26ABO), results in the production of a P135gag-myb-ets with modified biological properties on CNR cells. E26ABO infected CNR cells proliferate in minimal medium more efficiently than E26ABC, are unresponsive to bFGF and able to grow in soft agar. In contrast, CNR cells infected by viruses encoding Myb and Ets proteins either in the E26ABO or in the E26ABC configuration are bFGF responsive. Since Myb alone is sufficient to induce bFGF responsiveness on CNR cells, these results suggest that the c-Ets-1 C-terminus interferes with the Myb activity of the E26ABO P135gag-myb-ets protein in CNR cells.

Animals↗
PubMed1996

Genesis of discrete higher order DNA fragments in apoptotic human prostatic carcinoma cells.

Higher order DNA fragmentation may be an essential signal in apoptosis. We found that etoposide (VP-16) induced apoptosis in human DU-145 prostatic carcinoma cells in a time- and concentration-dependent manner. Chromatin condensation was morphologically evident only when cells detached from the monolayer; untreated or VP-16-treated attached cells retained a normal morphology. We describe a radiolabeled alu-I sequence-based quantitative field inversion gel electrophoresis (QFIGE) method that permitted observation and quantification of discrete high molecular weight DNA fragments in detached (apoptotic) and attached (preapoptotic) DU-145 cells. The DNA fragments generated during the apoptotic death of these cells were > or = 1 (mega-base pairs) mbp, 450-600 (kilo-base pairs) kbp, and 30-50 kbp; we observed that these DNA fragments increased 9 +/- 2-, 8 +/- 2-, and 25 +/- 11-fold versus control, respectively, with a 24-hr exposure to 30 microM VP-16 in attached cell populations. In detached VP-16-treated cells, there was accrual of 30-50-kbp DNA fragments with a concomitant loss of the > or = 1-mbp and 450-600-kbp fragments; internucleosomal DNA cleavage was never observed. This pattern of high molecular weight DNA fragmentation was inhibited by cycloheximide treatment and was common to other apoptotic agents, including melphalan and bleomycin. These findings suggest that the > or = 1-mbp and 450-600-kbp DNA fragments are products of endonuclease activation and are not topoisomerase II/DNA interactions. Finally, the generation of the 30-50-kbp DNA fragments may mediate chromatin condensation, which characterizes apoptosis.

Antineoplastic Agents↗
PubMed1996

Partial deletion of the gene encoding sterol 27-hydroxylase in a subject with cerebrotendinous xanthomatosis.

An Italian subject with cerebrotendinous xanthomatosis (CTX) was found to have a partial deletion of the gene encoding the enzyme sterol 27-hydroxylase (CYP27 gene). Southern blot analysis revealed that this deletion (approximately 2 kb) spans from intron 6 to the 3' flanking (3'FLK) region, eliminating exons 7-9, the last three exons of CYP27 gene. No sterol 27-hydroxylase mRNA was detected in proband cells, either by Northern blot analysis or by reverse transcription polymerase chain reaction (PCR). This suggests that the mutant mRNA devoid of the exon encoding the whole untranslated sequence (exon 9) might be rapidly degraded in the cytoplasm. We used inverse PCR to obtain a partial sequence of the 3'FLK region of the normal CYP27 gene; this allowed us to define the mechanism underlying the deletion. The established sequence was used to design suitable primers to perform step-wise sequences of a 1.7 kb segment of the 3'FLK region of the normal gene and of the deletion joint in the CTX patient. The analysis of the sequence data indicate that the deletion might result from a complex mechanism involving two intragenic recombinations between a) two 14 nucleotide complementary sequences, one in intron 6 and the other in the 3'FLK region: and b) AT-rich complementary sequences of the 3'FLK region, and a slipped mispairing between two 6 nucleotide direct repeats, one in intron 6 and the other in the 3'FLK region. Such repeats are brought close to each other by the formation of the stem-loops induced by the two intragenic recombinations. This is the first example of CTX caused by a rearrangement of CYP27 gene.

Adult↗
PubMed1996

[FLAIR images of subarachnoid hemorrhage].

We studied MR fluid attenuated inversion recovery (FLAIR) pulse sequences in 37 cases with subarachnoid hemorrhage caused by aneurysmal rupture. FLAIR sequence suppressed the CSF signal and produced very heavy T2 weighted images. This has been of particular benefit in identifying lesions at the margins of the brain, around the basal cisterns, in the brain stem and at the gray-white matter junction. Based on these findings, we were able to detect the subarachnoid hemorrhage. Subarachnoid hemorrhage was able to be demonstrated as high signal intensity on FLAIR sequences in all patients. Clear visualization of acute subarachnoid hemorrhage was able to be obtained by MR FLAIR sequences in not only Fisher's group 3 or 4, but also Fisher's group 2. Moreover it was suited for the detection of intraaxial hematoma, Sylvian hematoma, subdural hematoma and subarachnoid hemorrhage in the posterior fossa and interhemispheric fissure. Especially, it was useful for detecting intraventricular hemorrhage. Therefore, if patients suffering from subarachnoid hemorrhage present slight headache or atypical symptoms, sometimes it may be more suitable to perform MRI FLAIR pulse sequences first. Aneurysms were found in 21 cases (56.8%). When the aneurysmal size is more than 7 mm, the rate of detection becomes 100%. Aneurysms present various MR appearances because of flow characteristics. Aneurysms were demonstrated as low signal intensity except in 3 cases. In one out of 3 cases, aneurysms were revealed as high signal intensity and in the other two cases, it was revealed as mixed signal intensity. According to the previous studies, rapid flow was demonstrated as low signal intensity by vascular flow void, and delayed flow was demonstrated as high or mixed signal intensity by flow related enhancement and even echo rephasing. MR clearly delineates the size, the lumen, the flow, and the extraaxial location of aneurysms. In conclusion, MR FLAIR pulse sequences could be reliable and useful for diagnosis of subarachnoid hemorrhage, especially as screening tests for outpatients.

Adult↗
PubMed1997

Fast fluid-attenuated inversion-recovery MR of intracranial infections.

PURPOSE: To assess the usefulness of fast fluid-attenuated inversion-recovery (FLAIR) MR sequences in the diagnosis of intracranial infectious diseases. METHODS: We compared fast FLAIR images with conventional spin-echo images (T1- and T2-weighted) obtained in 20 patients with infectious diseases (six with encephalitis, five with brain abscesses, three with meningitis, two with meningoencephalitis, two with Creutzfeldt-Jakob disease, one with epidural empyema, and one with cysticercosis). Two neuroradiologists independently reviewed the FLAIR images and compared them with the conventional spin-echo images, obtaining agreement in all patients. RESULTS: FLAIR images of diagnostic quality were obtained in 18 patients. In two patients, FLAIR images were degraded by motion. Lesions in the patients with encephalitis and meningoencephalitis were better delineated on FLAIR images than on spin-echo images. FLAIR images clearly depicted lesions in the basal ganglia in both patients with Creutzfeldt-Jakob disease. In patients with brain abscess, meningitis, cysticercosis, and epidural empyema, FLAIR images provided no more information than conventional spin-echo images, and the lesions were seen better on postcontrast T1-weighted spin-echo images. CONCLUSION: Fast FLAIR images showed pathologic changes in intracranial infectious diseases better than or as well as conventional T2- and proton density-weighted spin-echo sequences. However, postcontrast T1-weighted spin-echo sequences resulted in better visibility of abscess, meningitis, cysticercosis, and epidural empyema than did FLAIR images.

Adolescent↗
PubMed2005

Differentiation between hepatic cyst and hemangioma: additive value of breath-hold, multisection fluid-attenuated inversion-recovery magnetic resonance imaging using half-Fourier acquisition single-shot turbo-spin-echo sequence.

PURPOSE: To evaluate the additive value of breath-hold, multisection fluid-attenuated inversion-recovery (FLAIR) magnetic resonance imaging (MRI) using half-Fourier acquisition single-shot turbo-spin-echo (HASTE) sequence as supplements to moderately and heavily T2-weighted fast-spin-echo (FSE) sequences in differentiating hepatic cyst from hemangioma. MATERIALS AND METHODS: A total of 183 lesions (127 hepatic cysts, 56 hepatic hemangiomas) in 117 patients were evaluated in this study. Three radiologists independently reviewed FLAIR MR images using a HASTE sequence and T2-weighted FSE MR images. Each radiologist used a five-point scale to rate his confidence in determination of hepatic cyst and hemangioma. RESULTS: All three reviewers were significantly better able to differentiate hepatic cyst from hepatic hemangioma with the combination of FLAIR imaging using HASTE and moderately and heavily T2-weighted FSE images (area under the receiver operating characteristic (ROC) curve, 0.99 for each reader) than with moderately and heavily T2-weighted FSE images alone (0.82-0.93; P < 0.05). FLAIR-HASTE imaging in addition to T2-weighted FSE sequences improved the diagnostic performance, including the sensitivity, specificity, accuracy, and confident diagnosis in the differentiation between hepatic hemangiomas and cysts. CONCLUSION: FLAIR-HASTE imaging is useful for distinguishing hepatic hemangioma from hepatic cyst without the use of contrast-enhanced MR images.

Adult↗
PubMed1990

Variation of contrast between different brain tissues with an MR snapshot technique.

The lack of tissue contrast in gradient-echo sequences with very short repetition times can be overcome by using a single inversion pulse prior to the entire imaging sequence. The contrast can be changed by variation of the time delay between the inversion pulse and the first excitation. This snapshot technique was introduced for very fast acquisition of images, but it also provides images with a strong contrast of gray to white matter and of brain tissue to cerebrospinal fluid. The authors designed a sequence that allows sufficient spatial resolution and good image quality. The measurement time is 1.2 seconds, and the in-plane resolution is 0.8 mm. A large variation in contrast with different inversion times was demonstrated on brain images of volunteers and patients.

Brain↗
PubMed1985

The invertible P-DNA segment in the chromosome of Escherichia coli.

In the chromosome of many strains of Escherichia coli K12 the excisable element e14 is found, which contains an invertible DNA region. This invertible P region, and the gene responsible for the inversion (pin) were cloned, together with other e14 sequences. The element e14 contains a gene which kills the host cell. This can be repressed by a function also coded by e14. The kil and repressor genes as well as the attachment site of the element were mapped in different regions of the element. The invertible segment and pin gene were sequenced. The invertible segment is 1794 bp long, and contains one large internal open reading frame of 879 bp and reading frames which overlap the end pont of the invertible segment. Although pin highly homologous to gin of phage Mu, neither the genetic organization of the P segment nor the sequence of the putative proteins resemble the invertible G segment of phage Mu (which codes for genes involved in tail fiber assembly). The complete DNA sequences of both invertible segments were screened for homology. No resemblance was found. The P segment is flanked by inverted repeat sequences of 16 bp. Comparison of these with related inversion systems points out that the recombination site maps probably within a 2-bp region. This cross-over site is contained within a short palindromic sequence (AAACC AA GGTTT) which is more or less conserved in the recombination sites of all related DNA invertases.

Bacterial Proteins↗