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At least 1,171 records · Page 65Linked to original sources
PubMed1992

A clinico-pathological study of the origin of adeno-carcinoma of the mid-thoracic oesophagus and results of surgical resection.

UNLABELLED: Adenocarcinomas of the mid-thoracic oesophagus are rare, and in a recent review were found to be 93 in 1099 (8.5%) in our series of carcinoma of the oesophagus and cardia. Study was planned to establish the origins of adeno carcinoma in the mid-thoracic oesophagus and to carry out a comparative evaluation of the results of surgery of such tumours derived from different origins. SUBJECT: 58 patients with adeno carcinoma in the mid-thoracic oesophagus undergoing surgical resection (10% of all resected patients). Protocol of the study: clinical, radiological, endoscopic and intra-operative study together with serial histopathological examination of all resected specimens, follow-up check. RESULTS: Four types of adenocarcinoma were identified according to their origin judged by the study results. Type 1: in 29 patients (20 males, 9 females) the tumour had risen from the cardia and had extended upwards in one continuous sheet. Type 2: in 16 cases (8 males, 8 females) adeno carcinoma had originated from the stomach within a hiatal hernia and had extended to the "mid" oesophagus. Type 3: 2 patients (1 male, 1 female) had adeno carcinoma in the mid-oesophagus surrounded by squamous epithelium and presumably originated from oesophageal glands. Type 4: in 11 patients (10 males, 1 female) the tumour had clearly risen from columnar epithelial lined oesophagus (Barrett). SURGICAL RESULTS: 2 patients died in hospital and one at home 25 days after operation (total mortality just over 5%). There was no serious morbidity. The long-term results per type were: Type 1: 4 survived 5 years or more, the remainder survived 14 months on average. Type 2: 2 survived 5 years or more, the remainder survived 16 months on average. Type 3: None survived 5 years, 2 survived 10 and 18 months. Type 4: None survived 5 years, 2 average survived was 11 months. CONCLUSIONS: Only 20% of the adeno carcinoma of the mid-oesophagus are associated with Barrett and these have the worst prognosis after surgical resection.

Adenocarcinoma↗
PubMed1992

Initiation of DNA replication in ColE1 plasmids containing multiple potential origins of replication.

We have investigated the frequency of replication origin usage in bacterial plasmids containing more than one potential origin. Escherichia coli recA- cells were selectively transformed with pBR322 monomers, dimers, or trimers. Plasmid DNA was isolated and digested with a restriction enzyme that cut the monomer only once, and the replicative intermediates (RIs) were analyzed by neutral/neutral two-dimensional agarose gel electrophoresis. Evidence for initiation outside the linearized plasmid was found only for oligomers. Moreover, in dimers, the intensity of the signal indicative for external initiation was equivalent to that reflecting internal initiation, whereas it was approximately twice as strong in trimers. To determine whether initiation could occur simultaneously at two origins in a single plasmid, we studied the replication of a neodimer in which both units could be unambiguously distinguished. The results showed that although both origins were equally competent to initiate replication, only one was active per plasmid. These observations strongly suggest that in ColE1 plasmids, replication initiates at a single site even when there are several identical potential origins per plasmid. In addition to the conventional two-dimensional gel patterns, novel specific patterns were observed with intensities that varied from one DNA sample to another. These unique patterns were the result of breakage of the RIs at a replication fork. This type of breakage changes both the mass and shape of RIs. When the entire population of RIs is affected, a new population of molecules is formed that may generate a novel pattern in two-dimensional gels.

DNA Replication↗
PubMedDate not supplied

P53 mutations as an identification marker for the clonal origin of bladder tumors and its recurrences.

The clonality of synchronous and metachronous bladder tumors has been studied for years with controversial results. Some recent studies support the 'polyclonal origin' hypothesis, i.e. that independently transformed different tumor cell clones exist in the same bladder cancer patient and arise from the field cancerogenisation affecting the entire bladder urothelium by environmental mutagens. Others could demonstrate a monoclonal origin of primary bladder tumors and its recurrences due to a single genetically transformed cell clone spread through the urinary system. With increasing understanding of the clonal origin of bladder tumors and recurrences, clonality markers might contribute to an early and accurate prediction of tumor recurrence and progression. We used p53 mutations as an identification marker permitting the prediction of clonality in bladder tumors and its recurrences. Primary tumors (n=33) and recurrences (n=63) were screened by direct genomic sequencing the p53 mutation hot spot region, exons 5-8. P53 mutations occurred in 12% in our cohort, predominantly in higher malignant (>or=G2), invasive (>or=T1) tumor samples. We were able to demonstrate intratumoral heterogeneity regarding the p53 status and that recurrences may occur from genetically unrelated primary tumor sites. Some of our results argue for a polyclonal origin of synchronous and metachronous bladder tumors possibly due to the field effect in bladder carcinogenesis. Evidence for a monoclonal origin was found in two cases: one case with a high malignant primary tumor and 3 metachronous recurrences, all of them harbouring the same exon 8 mutation found in the primary tumor; one case with identical mutations of exon 8 in the primary and one recurrent tumor. For further implications concerning clonality of recurrent bladder tumors, p53 status should be combined with a broader range of markers such as CGH and LOH pattern.

Biomarkers, Tumor↗
PubMed2004

Atypical squamous cells, cannot exclude HSIL: a review of original vs. duplicate thin-layer slides.

OBJECTIVE: To assess the utility of consensus review of original ThinPrep slides (Cytyc Corp., Boxborough, Masssachusetts) vs. duplicate slides and to identify the significance of the number of representative cells in classifying atypical squamous metaplastic cells, cannot exclude high grade squamous intraepithelial lesion (ASC-H). STUDY DESIGN: A duplicate ThinPrep slide was prepared from 19 cases of ASC-H. Both original and duplicate slides underwent blinded review by 4 pathologists. Consensus cytologic interpretations (75% agreement) were noted and compared with follow-up diagnoses. Dots with atypical metaplastic cells from each slide were counted and correlated with the consensus cytologic interpretation. RESULTS: Following review of 19 original and 19 duplicate slides, consensus interpretations were reached in 14 and 15 cases, respectively. Nine cases of squamous intraepithelial lesion (SIL) were confirmed by biopsies. Consensus interpretation of original and duplicate slides predicted 7 and 6 cases of SIL, respectively. Consensus interpretation of duplicate slides predicted 60% of histologically benign cases. Two-thirds of nonconsensus cases were histologically benign. Consensus interpretations for high grade SIL were reached more often on slides with greater numbers of atypical squamous metaplastic cells. Fewer abnormal cells were present on the duplicate slides. CONCLUSION: Consensus reviews of original and duplicate slides are equally useful in classifying atypical squamous cells, cannot exclude high grade squamous intraepithelial lesion, but may not be practical in all circumstances. HPV DNA testing of all such cases may better detect clinically significant cases.

Adult↗
PubMed2005

Aortic arch variation: a unique case with anomalous origin of both vertebral arteries as additional branches of the aortic arch distal to left subclavian artery.

We present the case of bilateral anomalous origin of both vertebral arteries (VAs) in a 20-year-old male patient who presented for routine contrast-enhanced CT follow-up examination of the chest. Contrast-enhanced CT revealed abnormal origins of both the VAs from the aortic arch distal to the origin of the left subclavian artery. Following this, CT angiography was performed, which confirmed the findings. To our knowledge, this is the first report of anomalous origins of both VAs beyond the origin of the left subclavian artery. The possible embryonic mechanism and the clinical importance of this variant is also reviewed.

Adult↗
PubMedDate not supplied

[Ultramorphometric study of the plastids in apical tuber cells of original and transgenic potato plants treated with ambiol].

Ultramorphometric characteristics of plastids in cells of apical tuber meristems of original and defensin gene-transfected potato (Solanum tuberosum L.) plants, either maintained under normal conditions or subjected to treatment with the antioxidant ambiol, were compared. Under normal conditions, the tuber cells of the original and transgenic potato plants differed in neither the number nor size of the plastids. Only certain quantitative distinctions in the development of individual ultrastructural characteristics of plastids were detected. Treatment with ambiol enhanced the differentiation of the internal membrane system of plastids in the cells of original and transgenic plants, especially the tubular membrane systems. Certain differences in the responses to ambiol of cell plastids of original and transgenic plants were related to plastid sizes and development of individual intraplastid structures. The results comply with earlier data on varying responses of mitochondria of original and transgenic plants to ambiol treatment.

Benzimidazoles↗
PubMed2005

[Investigation of the site of origin to develop micro-focal nasopharyngeal carcinoma].

OBJECTIVE: To investigate the prevalent area where the nasopharyngeal carcinoma (NPC) initially would develop most frequently in the nasopharynx. METHODS: From March, 1994 to June, 2003, the data of original micro-focus of 32 pathologically confirmed NPC were retrospectively reviewed, All cases were shown by CT to have stages T(0) or T(1) lesions. RESULTS: On clinical examination, only 3 cases (9.4%) were found to have original micro-tumor in the recess, the other 29 cases (90.6%) had developed from the other regions including 20 (69.0%) from the roof and 9 cases (31.0%) from the posterior wall, all with the mucosa in the recess smooth and symmetrical. However, CT images showed that membrane of all the nasopharyngeal walls, including the recess, were normal in 24 cases (75.0%); except the micro-foci were observed on one side of the posterior wall in 5 cases (15.6%) but still with the recess normal, One lateral wall and/or the recess were involved with abnormal appearance in 3 cases (9.4%) who were clinically found to have NPC focus originated from the recess. CONCLUSION: Our data suggest that the roof of nasopharyngeal cavity may be the area likely to develop the original NPC micro-focus, followed in frequency by the posterior wall, with the recess the least likely. The recess involvement observed in advanced lesions may be the extension of the NPC focus from the original site on the roof or the posterior wall of nasopharynx.

Adult↗
PubMed2005

Site of origin of nasal polyps: relevance to pathogenesis and management.

The site of origin of sino-nasal polyps was documented in 113 consecutive patients undergoing functional endoscopic sinus surgery (FESS). These patients were assigned pre-operatively to 4 clinical groups according to the out-patient recorded endoscopic appearance of their nasal cavities; chronic rhinosinusitis without polyps (CRSS) n=35, grade 1 polyps n=28, grade 2 polyps n=30 and grade 3 polyps n=20. In the group of patients diagnosed with polyps pre-operatively, 97.4% had polyps originating in the anterior ethmoid complex, of which 89.7% had polyps originating in the anterior ethmoidal cells and over 60% had polyps specifically originating from each of the following sites: the uncinate or infundibulum, the posterior ethmoid sinus, the frontal recess and the face of the bulla ethmoidalis. In the group diagnosed pre-operatively as CRSS without polyps, polyps were found in 60% of patients within the sinuses during surgery. In summary, our findings suggest that polyps originate from the middle meatus, and may be found at surgery when undetectable at pre-operative endoscopy.

Adult↗
PubMedDate not supplied

A fundamental plant evolutionary problem: the origin of land-plant sporophyte; is a new hypothesis possible?

The origin of the sporophyte in land plants represents a fundamental phase in the plant evolution. Today this subject is controversial and, in my opinion, scarcely considered in our textbooks and journals of botany, in spite of its importance. There are two conflicting theories concerning the origin of the alternating generations in land plants: the "antithetic" and the "homologous" theory. These have never been fully resolved. The antithetic theory maintains that the sporophyte and gametophyte generations are fundamentally dissimilar and that the sporophyte originated in an ancestor organism with haplontic cycle by the zygote dividing mitotically rather than meiotically, and with a developmental pattern not copying the developmental events of the gametophyte. The sporophyte generation was an innovation of critical significance for the land-plant evolution. By contrast, the homologous theory simply stated that a mass of cells forming mitotically from the zygote adopted the same developmental plan of the gametophyte, but giving origin to a diploid sporophyte. In this context, a very important question concerns the possible ancestor or ancestors of the land plants. Considerable evidences at morphological, cytological, ultrastructural, biochemical and, especially, molecular level, strongly suggest that the land plants or Embryophyta (both vascular and non-vascular) evolved from green algal ancestor(s), similar to those belonging to the genus Coleochaete, Chara and Nitella, living today. Their organism is haploid for most of their life cycle, and diploid only in the zygote phase (haplontic cycle). On the contrary, the land plants are characterized by a diplo-haplontic life cycle. Several questions are implied in these theories, and numerous problems remain to be solved, such as, for example, the morphological difference between gametophyte and sporophyte (heteromorphism, already present in the first land plants, the bryophytes), and the strong gap existing between these last with a sporophyte dependent on the gametophyte, and the pteridophytes having the gametophyte and sporophyte generations independent. On the ground of all of the evidences on the ancestors of the land plants, the antithetic theory is considered more plausible than the homologous theory. Unfortunately, no phylogenetic relationship exists between some green algae with diplontic life cycle and the land plants. Otherwise, perhaps, it should be possible to hypothesize another scenario in which to place the origin of the alternating generations of the land plants. In this case, could the gametophyte be formed by gametes produced from the sporophyte, through their mitoses or a delayed fertilization process?

Biological Evolution↗
PubMed2006

Relationship between nuclear grade of ductal carcinoma in situ and cell origin markers.

Ductal carcinoma in situ (DCIS) is a group of heterogeneous lesions genetically, morphologically, and biologically. Recently, breast epithelium in the terminal ductal lobular unit has been sub-classified based on the expression of several cytokeratin markers as stem cells (CK5/6 +), luminal cells (CK8, CK18 +), and basal cells (CK14, CK17 +). In this study we describe the relationship between DCIS of different nuclear grades (non-high grade and high grade) and these cell origin markers. Fifty-three cases of non-high grade and 46 cases of high grade DCIS were selected, and representative sections from each case were stained with antibodies to these cytokeratin markers. High grade DCIS showed significantly higher rates of expression with stem and basal cell markers compared with non-high grade DCIS (p <0.05). The majority of DCIS, both high grade and non-high grade, expressed luminal cell markers (67% to 91%) and single type of cell origin marker (72% to 87%). High-grade DCIS more frequently co-expressed all three types of cell origin markers compared with non-high grade DCIS (p <0.05). In summary, a subset of high grade DCIS frequently rises from stem or/and basal cell populations; the subset is associated with poor prognosis in invasive breast carcinoma. Thus, these markers may be used to identify a potentially more aggressive subgroup of breast carcinoma at its pre-invasive stage (DCIS), and to manage it accordingly. Second, most DCIS express luminal cell markers, suggesting that malignant transformation occurs relatively late along the cell differentiation pathway, contrary to the traditional belief that most neoplasms arise from a more primitive stem cell population. Third, the majority of DCIS exclusively express one type of progenitor marker, indicating that in most incidences they may arise from a single progenitor population. Last, triple expression of all types of cell origin marker is frequently associated with high grade DCIS, suggesting that more complicated pathways are involved in these more aggressive lesions. Further studies are needed to delineate the relationships of cell origin markers in DCIS and invasive carcinoma to the clinical outcome.

Biomarkers, Tumor↗
PubMed1991

Replication of plasmid R6K origin gamma in vitro. Dependence on dual initiator proteins and inhibition by transcription.

We have developed a more efficient in vitro replication system for the plasmid R6K with the objective of dissecting the mechanism of activation of replication origins at a distance. Using this in vitro system we have shown that the activation of replication origin gamma of R6K is absolutely dependent on two exogenously added initiator proteins: namely the host-encoded DnaA and the plasmid-encoded Pi proteins. Replication was inhibited by novobiocin, suggesting a requirement for DNA gyrase. Surprisingly, rifampicin stimulated in vitro replication significantly, and this stimulation was manifested in the quantitative enhancement of replication without any noticeable qualitative change in the reaction products. This result suggests that transcription at or near the gamma origin keeps it repressed. Replication intermediates that were allowed to accumulate by dideoxynucleoside triphosphate incorporation were analyzed both by restriction enzyme digestion and by electron microscopy, and both sets of analyses revealed initiation from the gamma origin resulting in theta-type replication intermediates. Further development of this system should help us to understand how DNA-protein interaction at the gamma origin/enhancer activates the distal origins alpha and beta.

Autoradiography↗
PubMed2006

Vertebral artery origin stent placement with distal protection: technical and clinical results.

OBJECTIVE: To report the feasibility, safety, and 1-month results of performing stent placement for vertebral origin stenosis with the use of a distal protection device. Distal protection devices have been shown to reduce the number of cerebral emboli and subsequent ischemic events when used as adjuncts to percutaneous carotid intervention; however, one case of the use of a distal protection device for vertebral artery has been reported in the literature. METHODS: We retrospectively determined rates of technical success and 1-month stroke or death associated with stent placement by using distal protection (Filter EX; Boston Scientific, Natick, Mass) in patients with symptomatic vertebral artery origin stenosis. Technical success was defined as successful deployment of distal protection device and stent at target lesion followed by successful retrieval of the device and a final residual stenosis of less than 30%. Other outcomes ascertained included any stroke, death, and semiquantitative assessment of particulate material retained by the filter device. RESULTS: The mean age of the 12 treated patients was 68 years (range, 52-88 years) and the group included 9 men and 3 women. The mean percentage of vertebral artery origin stenosis was 71 +/- 6%. Femoral and radial approaches were used in 9 and 3 cases, respectively. Technical success was achieved in 11 of the 12 patients in whom distal protection device placement was attempted. Postprocedure residual stenosis was 5 +/- 4%. Eight devices held macroscopically visible embolic debris (large and small amounts in 3 and 5 devices, respectively). No stroke or death was observed in the 1-month follow-up. CONCLUSION: The present study demonstrates the feasibility of performing stent placement for vertebral artery origin stenosis by using a distal protection device. Further studies are required to determine the effectiveness of this approach for vertebral artery origin atherosclerosis.

Aged↗
PubMed1991

Specific destruction of host-reactive mature T cells of donor origin prevents graft-versus-host disease in cyclophosphamide-induced tolerant mice.

In cyclophosphamide (CP)-induced tolerance, a long lasting skin allograft tolerance was established in many H-2-identical strain combinations without graft vs host disease. Destruction of donor-reactive T cells of host origin, followed by intrathymic clonal deletion of these cells, has been revealed to be the chief mechanisms of this system. Here, we studied the fate of host-reactive populations in donor-derived T cells of C3H/He (C3H) (H-2k, Mls-1b, Mls-2a) mice rendered CP-induced tolerant to AKR/J (AKR) (H-2k, Mls-1a, Mls-2b), by assessing AKR-derived Thy-1.1+ T cells bearing TCR V beta 3 that are specifically reactive with Mls-2a-encoded Ag of the recipient C3H mice. In the AKR-derived Thy-1.1+ lymph node cells of the C3H mice that had been treated with AKR spleen cells plus CP, CD4(+)-V beta 3+ T cells were obviously decreased by day 10 after the CP treatment. At this stage, the Thy-1.1+ T cells were not detected in the C3H thymus, suggesting that the obvious decrease of CD4(+)-V beta 3+ T cells of AKR origin was not due to intrathymic clonal deletion in the recipient C3H mice. Therefore, the destruction of the host-reactive mature T cells of donor origin, as well as that of the donor-reactive mature T cells of host origin, occurred by the CP treatment at the induction phase. Furthermore, after the establishment of intrathymic mixed chimerism in the recipient C3H mice, V beta 3+ T cells were not detected among the Thy-1.1+ T cells of AKR origin in the mixed chimeric thymus, suggesting that the host-reactive immature T cells repopulated from the injected donor hematopoietic cells were clonally deleted in the recipient thymus. These two mechanisms appear to prevent graft vs host disease in CP-induced tolerance.

Animals↗
PubMed2006

Symptomatic anomalous origination of the left coronary artery from the opposite sinus of valsalva. Clinical presentations, diagnosis, and surgical repair.

Anomalous origination of a coronary artery can have serious, even fatal, consequences. Intravascular ultrasonography has recently provided new insights into anomalous coronary artery origination from the opposite sinus of Valsalva. On the basis of these insights, we describe 3 typical forms of this anomaly with left coronary artery involvement, including clinical presentations, diagnostic methods (particularly intravascular ultrasonography), and details of surgical treatment. In this case series, the left coronary artery originated from the noncoronary sinus in 1 patient and from the right sinus in another patient. In the 3rd patient, both the left and right coronary arteries originated from the ascending aorta above the sinotubular junction. Baseline areas of stenosis ranged from 48.6% to 70.1%. Intravascular ultrasonography was the only method that enabled us to clarify the mechanisms and the severity of the anomaly. Pharmacologic challenge was useful to predict worsening that might have occurred under physiologic conditions. We found that, in cases of symptomatic left anomalous coronary artery origination from the opposite sinus of Valsalva, the proximal segment of the left coronary artery consistently has (1) an intramural course inside the aortic wall; (2) hypoplasia, as determined by its circumference; and (3) a cross-sectional ovaloid deformity (lateral compression) with phasic and exercise-induced worsening of the deformity With regard to surgical treatment, ostioplasty is preferable to coronary bypass. To establish sound guidelines for managing these anomalies, a larger series should be studied prospectively with quantitative parameters and long-term follow-up.

Aged↗
PubMed2005

Tissue tracking imaging for identifying the origin of idiopathic ventricular arrhythmias: a new role of cardiac ultrasound in electrophysiology.

Several strategies for mapping ventricular outflow tract tachycardia have been reported as useful indices for differentiating between those originating from the right and the left side. Recently, tissue tracking imaging (TTI) has been demonstrated as a novel non-invasive modality for identifying the origin of outflow tract tachycardias. Tissue tracking imaging is an ultrasonographic technique that measures the myocardial motion amplitude towards the transducer in each region during systole, identifying regional myocardial displacement on the basis of myocardial velocities using color Doppler myocardial imaging principles. In this technique, the origin of the arrhythmia could be recognized as the site where the earliest color-coded signal (ECCS) appeared on the myocardium at the onset of the systole. In preliminary studies this modality was found to be useful in differentiating outflow tract ventricular tachycardias. ECCS was always found below or at the level of the pulmonary valve in all arrhythmias which could be ablated from the right ventricular outflow tract, while in those where the ECCS was above and close to the pulmonary valve it could be ablated from the left sinus of valsalva. These results indicate that TTI can provide detailed and accurate information on the arrhythmia origin of outflow tract tachycardia and may be useful for differentiating between an outflow tract tachycardia originating from the LV epicardium remote from the LSV and that from the LSV. Newer advances in echocardiographic technologies like high resolution, high frame rate real time three dimensional echocardiography with speckle tracking may further improve the precise localization of arrhythmias in the future.

Editorial↗
PubMedDate not supplied

[Meiotic and parental origin of extra chromosome 21 in children with regular trisomy 21].

INTRODUCTION: Down syndrome (DS) or trisomy 21 is the most common chromosomal abnormality in live birth children. Most cases are regular trisomies 21 secondary to a maternal non-disjunction (ND). Meiotic and parental origins have been recently investigated by segregating genetic markers from DNA hypervariable regions. OBJECTIVE: To identify the meiotic and parental origin in children with regular trisomy 21. MATERIALS AND METHODS: There were analyze 20 groups of three (every group included parents and child with Down syndrome). There were used soothe following markers: D21S11, D21S1260, and D21S265. RESULTS: The ND occurred during the first meiotic division (M1) in 13 cases and at the second meiotic division (M2) in the other seven. Twelve out of the 13 NDs from the first group were maternal and one paternal. The parental origin within the M2 group was not elucidated. CONCLUSIONS: Meiotic origin was identified in all cases. As in other reports, the origin of trisomy 21 in the present population is mainly secondary to a maternal ND in M1.

Child↗
PubMed1991

[A theoretical study on the biological origins of Chinese herbs].

Ten new theoretical points concerning the biological origins of Chinese herbs are presented in this paper, i.e. continuity of the biological origins of Chinese herbs, mutation of the biological origins of Chinese herbs; optimum seeking theory of rising species of medicinal herbs; mono-original and limit d multi-original Chinese herbs; etc.

Drug Contamination↗
PubMed1991

Hemoglobin Terre Haute arginine beta 106. A posthumous correction to the original structure of hemoglobin Indianapolis.

The initial report of Hb Indianapolis described two affected individuals with the phenotype of severe beta-thalassemia that was dominantly inherited. The structure of this variant could not be deduced by standard techniques because of its extreme instability. Because of this limitation, the structure was ascertained by analysis of the abnormal globin chain, which had been radioactively labeled. These studies strongly suggested that the structure of this variant was cysteine beta 112 to arginine. Subsequent to this report, two additional families with Hb Indianapolis were found. The carriers were minimally affected and the abnormal hemoglobin was only mildly unstable. This major difference in phenotypic expression suggested that further investigation of the original family should be carried out. Unfortunately, both of the original carriers of the variant succumbed to their severe anemia prior to the subsequent reports. However, by the use of the polymerase chain reaction, enough DNA was obtained to sequence the third exon of the beta-globin gene in the original family from the DNA scraped off a 10-year-old bone marrow microscope slide. These studies revealed a substitution of leucine to arginine at position 106 of the beta-globin chain. The polymerase chain reaction results may be consistent with the original protein structural data, if incomplete tryptic cleavage of this arginine residue occurred in the original sample. We have renamed this variant Hb Terre Haute in an attempt to avoid confusion with the Cys beta 112----Arg substitution.

Arginine↗