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Cunha GR, Young P, Christov K, Guzman R, Nandi S, Talamantes F, Thordarson G. Mammary phenotypic expression induced in epidermal cells by embryonic mammary mesenchyme. ACTA ANATOMICA 1995; 152:195-204. [PMID: 7572029 DOI: 10.1159/000147698] [Citation(s) in RCA: 70] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The goal of this research was to establish methods for inducing mammary epithelial differentiation from nonmammary epithelium. For this purpose, mid-ventral or dorsal epidermis (skin epithelium; SKE) from 13-day rat or mouse embryos was associated with 13-day embryonic mouse mammary mesenchyme (mammary gland mesenchyme; MGM) (mouse MGM+rat or mouse SKE). The resultant MGM+SKE recombinants as well as controls (homotypic mouse mammary recombinants, homotypic mouse skin recombinants and mouse mammary mesenchyme by itself) were grafted under the renal capsule of syngeneic or athymic female nude mouse hosts. Most female hosts were induced to undergo lactogenesis by grafting an adult pituitary which elicited a state of hyperprolactinemia. Tissue recombinants of mouse MGM+rat or mouse SKE grown for 1 month in vivo formed a hair-bearing keratinized skin from which mammary ductal structures extended into the mesenchyme. The ducts were composed of columnar luminal epithelial cells as well as basal, actin-positive myoepithelial cells. When grown in pituitary-grafted hosts, the ductal epithelial cells expressed casein and alpha-lactalbumin as judged by immunocytochemistry. The expression of caseins in MGM+SKE recombinants was confirmed by Western blot. The epithelial cells in mouse MGM+rat SKE recombinants expressing milk proteins were shown to be rat cells while the surrounding connective tissue was composed of mouse cells based upon staining with Hoechst dye 33258. Using mammary-specific markers, these studies confirmed the earlier morphological studies of Propper and unequivocally demonstrated for the first time that embryonic mammary mesenchyme can induce morphological and functional mammary differentiation from nonmammary epithelium.
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102
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Cunha GR, Young P, Hamamoto S, Guzman R, Nandi S. Developmental response of adult mammary epithelial cells to various fetal and neonatal mesenchymes. EPITHELIAL CELL BIOLOGY 1992; 1:105-18. [PMID: 1307943] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Adult mouse mammary epithelial cells were isolated and grown in combination with mesenchyme from the following sources: embryonic preputial gland, foot skin, tail skin, genital tubercle skin, mammary gland, and neonatal uterus, vagina and urinary bladder. Following 1 month of in vivo cultivation of the tissue recombinants as grafts underneath the renal capsule of normal female or hyperprolactinaemic (pituitary-grafted) hosts, the specimens were analysed histologically and immunocytochemically for the expression of milk proteins, smooth muscle actin, and cytokeratins. Mesenchymal effects on adult mammary epithelium varied with the source of the mesenchyme and the hormonal status of the host. In normal female hosts preputial gland mesenchyme induced extensive mammary epithelial growth and ductal branching morphogenesis with epithelial differentiation and ductal pattern being comparable to that observed in homotypic recombinants composed of mammary gland mesenchyme plus adult mammary epithelium. Other mesenchymes (from foot, tail, genital tubercle and uterus) preserved ductal morphology and normal epithelial differentiation, but elicited minimal epithelial growth and branching morphogenesis in adult mammary epithelium. In association with urogenital sinus, vaginal or bladder mesenchymes ductal branching morphogenesis of the mammary epithelium was absent or greatly distorted and the epithelium exhibited a stratified cuboidal phenotype even though considerable epithelial growth had occurred. In hyperprolactinaemic hosts (which received a pituitary graft) epithelial growth, alveolar morphogenesis, and synthesis of casein and milk fat globule protein was stimulated in all tissue recombinants although to different extents. Alveolar morphogenesis and milk protein expression were extensive in tissue recombinants prepared with mesenchyme from embryonic mammary gland, preputial gland, tail skin and urinary bladder, but were minimal in tissue recombinants prepared with foot or genital tubercle skin. Few milk-protein-positive alveoli formed in tissue recombinants composed of mammary epithelium combined with urogenital sinus or vaginal mesenchyme, even following growth in pituitary-grafted hosts. These findings demonstrate: (1) that adult mammary epithelial cells are responsive to the growth-promoting influences of heterotypic embryonic and neonatal mesenchymes; (2) that mammary growth and branching morphogenesis are induced to variable extents by different mesenchymes; (3) that fibrous (non-adipose) mesenchymes are effective inducers of mammary epithelial development; and (4) that the ability to form alveoli and produce milk proteins in adult mammary epithelial cells is critically dependent upon the nature of the connective tissue environment.
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103
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Weiner MF, Denke M, Williams K, Guzman R. Intramuscular medroxyprogesterone acetate for sexual aggression in elderly men. Lancet 1992; 339:1121-2. [PMID: 1349145 DOI: 10.1016/0140-6736(92)90723-g] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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104
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Aviles A, Rodriguez L, Guzman R, Talavera A, Garcia EL, Diaz-Maqueo JC. Angiocentric T-cell lymphoma of the nose, paranasal sinuses and hard palate. Hematol Oncol 1992; 10:141-7. [PMID: 1398510 DOI: 10.1002/hon.2900100303] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Sixty-five cases of malignant lymphoma of the nose, paranasal sinuses and hard palate were retrospectively analysed to identify the presence or absence of angiocentric lesions. We observed that the 23 patients with angiocentric lesions had a worse prognosis with a shorter duration of response and also a shorter duration of survival, compared with 42 cases of malignant lymphoma of the same anatomical region but without angiocentric lesions. Patients with angiocentric lymphoma were associated with other bad prognostic factors such as elevated levels of lactic dehydrogenase and beta 2 microglobulin, local bone destruction and lymphopenia. Immunophenotyping studies showed that most patients with angiocentric lesions had T cell lymphomas (18 of 23, 78 per cent). We believe that patients with angiocentric T cell lymphomas of the nose, paranasal sinuses and hard palate represent a distinctive clinico-pathological entity with different clinical presentation and outcome. Patients with angiocentric T cell lymphomas had frequent relapse at extranodal sites and combined therapy should be considered as the initial therapeutic approach.
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105
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Kwan H, Pecenka V, Tsukamoto A, Parslow TG, Guzman R, Lin TP, Muller WJ, Lee FS, Leder P, Varmus HE. Transgenes expressing the Wnt-1 and int-2 proto-oncogenes cooperate during mammary carcinogenesis in doubly transgenic mice. Mol Cell Biol 1992; 12:147-54. [PMID: 1530875 PMCID: PMC364078 DOI: 10.1128/mcb.12.1.147-154.1992] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The Wnt-1 and int-2 proto-oncogenes are transcriptionally activated by mouse mammary tumor virus insertion mutations in virus-induced tumors and encode secretory glycoproteins. To determine whether these two genes can cooperate during carcinogenesis, we have crossed two previously characterized lines of transgenic mice to obtain bitransgenic animals carrying both Wnt-1 and int-2 transgenes under the control of the mouse mammary tumor virus long terminal repeat. Mammary carcinomas appear earlier and with higher frequency in the bitransgenic animals, especially the males, than in either parental line. Nearly all bitransgenic males develop mammary neoplasms within 8 months of birth, whereas only 15% of Wnt-1 transgenic males and none of the int-2 transgenic males have tumors. In virgin bitransgenic females, tumors occur approximately 2 months earlier than in their Wnt-1 transgenic siblings; int-2 transgenic females rarely exhibit tumors. Preneoplastic glands from the bitransgenic animals of either sex demonstrate pronounced epithelial hyperplasia similar to that seen in Wnt-1 transgenic virgin females and males, and both transgenes are expressed in the hyperplastic glands and mammary tumors. RNA from the int-2 transgene is more abundant in mammary glands from bitransgenic animals than from int-2 transgenic animals; the increase is associated with high levels of RNA specific for keratin genes 14 and 18, suggesting that Wnt-1-induced epithelial hyperplasia is responsible for the observed increase in expression of the int-2 transgene.
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106
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Downs AR, Guzman R, Formichi M, Courbier R, Jausseran JM, Branchereau A, Juhan C, Chakfe N, King M, Guidoin R. Etiology of prosthetic anastomotic false aneurysms: pathologic and structural evaluation in 26 cases. Can J Surg 1991; 34:53-8. [PMID: 1997148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
To determine the etiology of anastomotic false aneurysms (AFAs), 26 textile graft specimens, removed because of AFA, were studied morphologically, histologically and by scanning electron microscopy. No cases of suture-related failures leading to AFA were found. Nine cases of frayed grafts were documented but were not the cause of AFA formation. In three cases, chemical degradation of the fibres, which may have been secondary to lipid infiltration, may have contributed to AFA formation. There were no cases of overt clinical infection, but the presence of bacteria was documented by scanning electron microscopy in 20 cases. The role of bacteria is not well defined, but they may be a factor in host arterial-wall degeneration as a cause for AFA formation.
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107
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Avilés A, Díaz-Maqueo JC, Torras V, Guzman R. [Hodgkin's disease treated with chemotherapy at reduced dosage]. SANGRE 1990; 35:341-4. [PMID: 1705365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Fifty-six patients with Hodgkin's disease in advanced stages (III-IV) were entered in a study aimed to compare standard doses (28 cases) with low doses (28 cases) ABVD regimen. Both groups had similar clinico-pathological features. The group receiving standard doses chemotherapy achieved complete remission rate of 89% versus 85% for the low-doses group. The number of relapses was, respectively, 8 and 9, and the duration of remission was 66 and 57 months, respectively. Presently, 24 patients have died, 11 of the standard doses group and 13 of the reduced doses group. Toxicity was notably higher in the group receiving standard dosage, where fatal myelosuppression was present in two instances. Those data appear to suggest that chemotherapy with reduced doses for Hodgkin's disease can attain similar response rate and survival than those achieved with standard treatment, with the advantages of a lower toxicity.
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108
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Batt M, Gagliardi JM, Avril G, Guzman R, Guidoin R, Hassen-Khodja R, Marois M, Le Bas P. Human umbilical vein grafts as infrainguinal bypasses: long-term clinical follow-up and pathological investigation of explanted grafts. CLIN INVEST MED 1990; 13:155-64. [PMID: 2208831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
This retrospective study examines 105 consecutive infrainguinal bypasses using human umbilical vein (HUV) grafts as blood conduits over a 9 year period. In addition, 39 segments of these grafts were harvested at reoperation and submitted for morphologic, histologic, and scanning electron microscopy examinations. Fifty-two below-knee femoro-popliteal and 53 femoro-distal bypasses were performed in 93 patients. Sixty-seven per cent of these bypasses were performed for either rest pain (18%) or gangrene (49%) and 29% were performed for acute ischemia. Primary and secondary patency rates were not statistically different and were 38% and 29% at 1 and 3 years respectively. Factors found to have a significant effect on patency were site of distal anastomosis, state of distal run-off, and indication for operation. Other complications requiring reoperation included aneurysm formation (8 cases), infection (6 cases), mural thrombus (2 cases), and stenosis (2 cases). Pathologic examination revealed a damaged luminal surface in 22 grafts, deep folds in 8 grafts and delamination of the graft wall in 16 cases. Bacteria were seen in the folds of the grafts and, in addition, the presence of bacteria was documented in 7 out of 26 clinically non-infected grafts. The combination of poor patency rates and pathologic evidence of biodegradative phenomena have led us to discontinue HUV as an arterial substitute.
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109
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Ranalli DN, Guzman R, Schmutz JA. Craniofacial and intraoral manifestations of congenital hemifacial hyperplasia: report of case. ASDC JOURNAL OF DENTISTRY FOR CHILDREN 1990; 57:203-8. [PMID: 2345214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The craniofacial and intraoral developmental and morphologic characteristics of the rare congenital disorder known as hemifacial hyperplasia are reviewed. The case of a 7.7-year-old Caucasian girl affected by this malformation is presented to corroborate and supplement existing clinical knowledge regarding hemifacial hyperplasia. Suggestions are made regarding the implications of early differential diagnosis and treatment planning of affected individuals. Special emphasis is placed on the advantage of multidisciplinary team management.
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110
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Merhi Y, Roy R, Douville Y, Ben-Slimane S, Guzman R, Downs A, Hébert J, Roy PE, Guidoin R. Fresh venous femoral autografts and allografts as carotid substitutes in matched dogs from the same litter. THE JOURNAL OF CARDIOVASCULAR SURGERY 1990; 31:147-55. [PMID: 2341469] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Pathological and biochemical investigations were performed on femoral veins used as fresh autografts and allograft substitutes in the carotid arteries of dogs from the same litter and separated in two groups described as compatible and incompatible after a mixed leukocyte culture (MLC). After 5 months of implantation, all the arterial substitutes were patent. The analyses gave the following results: 1. The haematologic parameters were not affected by the grafts. 2. Light microscopy (LM) and scanning electron microscopy (SEM) indicate a thrombotic accumulation and the presence of inflammatory cells in the compatible and the incompatible allografts. The occurrence of pathological changes was more pronounced in the incompatible group. 3. Immunostaining of anti-factor VIII-related antigen reveals a better preservation of the endothelial cell wall on the autograft. 4. The 6-keto-PGF1 alpha/TXB2 ratios of the autografts and the compatible allografts were similar.
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111
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Batt M, Avril G, Gagliardi JM, Guzman R, Guidoin R, Boas N, Daune B, Hassen-Khodja R, Le Bas P. Femorodistal bypass using the chemically processed human umbilical vein graft: 9-year experience. Can J Surg 1990; 33:61-5. [PMID: 2302603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
To evaluate patency, limb salvage rates and complications associated with the use of human umbilical vein as an arterial substitute, the authors carried out a retrospective review of 52 femorodistal bypasses performed over 9 years using human umbilical vein. Indications for operation included acute ischemia, rest pain and nonhealing ulceration or gangrene. There were 28 early occlusions, which resulted in a 1-month primary patency rate of 46% and a secondary patency rate of 52%. The primary and secondary patency rates at 1 year were 18% and 19% respectively. The mean limb salvage rate at 1 month was 57% and at 1 year 34%. Three aneurysms occurred (two anastomotic, one graft). Factors found to have a significant effect on patency rates were indication for operation and state of distal runoff. Infection occurred in 6% of grafts and led to amputation in every case. These disappointing results have caused the authors to discontinue use of human umbilical vein as an arterial substitute.
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112
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Guzman R, Elliott MA, Rossie KM. Odontodysplasia in a pediatric patient: literature review and case report. Pediatr Dent 1990; 12:45-8. [PMID: 2169046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
A case of a three-year-old Caucasian male with odontodysplasia is presented. Although the etiology of this condition is unknown, this anomaly involves both the mesodermal and ectodermal dental components and results in deficient and abnormal formation of dentin and enamel. The orofacial characteristics and dental findings of the condition are presented in this case report.
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113
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Gill F, Guzman R, Guidoin R, Avril G, Charara J, Batt M, Roy PE, Marois M, Graham AM, Symes JF. An histo-morphological evaluation of ninety surgically excised human umbilical vein grafts. JOURNAL OF BIOMEDICAL MATERIALS RESEARCH 1989; 23:363-80. [PMID: 2613744 DOI: 10.1002/jbm.820231410] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Morphological, histological, and scanning electron microscopy examinations were performed on 90 surgically excised human umbilical vein grafts. Most of the explanted grafts were removed because of thrombosis or infection and were removed typically from a patient in the mid 60s and after an average duration of implantation of 11 months. Multiple structural defects were found including deep folds, breaks on the luminal surface, and delamination. These areas as well as anastomotic sites represented potential areas for thrombotic accumulation. A higher incidence of infection was observed in grafts composed of 2 or 3 segments. Bacteria were often found in folds and could be seen invading the wall of the prosthesis. In addition, bacteremic colonization was often seen in noninfected grafts. The late aneurysmal formations were also of particular concern. The biodegradation of the wall and the disruption of the polyester mesh were the probable causes. The second generation Dardik Biograft aimed at reducing these formations. The success of this new processing remains to be evaluated.
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114
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Gaitan E, Cooksey RC, Meydrech EF, Legan J, Gaitan GS, Astudillo J, Guzman R, Guzman N, Medina P. Thyroid function in neonates from goitrous and nongoitrous iodine-sufficient areas. J Clin Endocrinol Metab 1989; 69:359-63. [PMID: 2753978 DOI: 10.1210/jcem-69-2-359] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
We compared thyroid function between newborns from goitrous and nongoitrous localities in which iodine intake has been supplemented since 1955. Cord serum samples were analyzed in 185 infants born during a 9-month period (1986-1987) in 2 goitrous and 1 nongoitrous localities of western Colombia. Urinary iodine was determined in all mothers before delivery. No significant differences were found among neonates of the 3 localities (Kruskal-Wallis test) for the various thyroid hormone values, and all values were within the normal range, although there was a trend in distribution of TSH to higher values in both goiter areas. Thyroid autoantibodies (antithyroglobulin and antithyroid microsomal) were negative in all neonates, and iodine intake, as indicated by urinary iodine, was adequate and similar among the mothers of the 3 groups. Those newborn infants with serum TSH values higher than 20 mU/L were reexamined 5-7 months later. At this time, all infants had lower serum TSH values and their serum free T4 index and T3 values were normal. Gestational age, weight, and height at birth were normal and also equal among the neonates in the 3 localities. These results indicate that neonates from goitrous iodine-sufficient areas have thyroid function similar to that of infants born in nongoitrous areas equally supplemented with iodine, and therefore, they are not more at risk to develop congenital hypothyroidism.
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115
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Guzman R, Torres JL, Carbonell RG, Kilpatrick PK. Water-soluble nonionic surfactants for affinity bioseparations. Biotechnol Bioeng 1989; 33:1267-76. [DOI: 10.1002/bit.260331007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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116
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Julien S, Gill F, Guidoin R, Guzman R, Charara J, Roy PE, Marois M, Laroche G, Batt M, Roy P. Biologic and structural evaluation of 80 surgically excised human umbilical vein grafts. Can J Surg 1989; 32:101-7. [PMID: 2920312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Human umbilical vein is a valuable alternative to autogenous saphenous vein in lower-limb revascularization. However, the long-term patency is not as good. To understand better the reasons for this, the authors studied the biologic and structural changes occurring in 80 segments of human umbilical vein (HUV) grafts excised from 70 patients. Morphologic, histologic and scanning electron microscopy examinations were performed on each specimen. It was noted that increasing duration of implantation was associated with greater encapsulation and less surrounding inflammatory reaction. Twenty-six percent of clinically noninfected grafts were found to harbour bacteria. Bacteremic colonization was often in the folds of the luminal surface. As a result of these findings, the authors emphasize the need for complete excision of clinically infected grafts. Anastomoses between HUV segments are discouraged because they are associated with a high frequency of infection and a corresponding decrease in duration of implantation. Delamination of the wall was common, and such sites may represent areas at risk for further degradation. Continued surveillance of the biologic and structural changes occurring in excised grafts remains an important method in increasing our understanding of the evolutive complications of HUV grafts.
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117
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Guzman R, Kirkpatrick J, Forward K, Lim F. Failure of parenteral metronidazole in the treatment of pseudomembranous colitis. J Infect Dis 1988; 158:1146-7. [PMID: 3183427 DOI: 10.1093/infdis/158.5.1146] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
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118
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Torres JL, Guzman R, Carbonell RG, Klipatrick PK. Affinity surfactants as reversibly bound ligands for high-performance affinity chromatography. Anal Biochem 1988; 171:411-8. [PMID: 3407942 DOI: 10.1016/0003-2697(88)90507-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Pyridine was coupled covalently to a nonionic ethoxylated alcohol: octaethylene glycol n-hexadecyl ether. This modified surfactant was found to be a reversible, competitive inhibitor of horse serum cholinesterase. The surfactant bound irreversibly, in aqueous media, to octadecyl-bounded reverse phase silica particles commonly used for high-performance liquid chromatography. The amount of ligand bound was found to be 550 mumol/ml of packing, a concentration that is over 100 times higher than what can be normally bound to agarose affinity chromatography supports. With this packing, a 280-fold purification of cholinesterase from horse serum and a 79-fold purification of human serum cholinesterase were accomplished, with yields greater than 80%, using a 2-cm-long column and a 7-min elution time. The affinity surfactant could be eluted from the column using a 6:4 (v/v) mixture of methanol and isopropanol. This technique should be generally applicable in the development of biospecific supports for high-performance affinity chromatography.
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119
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Mishra M, Guzman R, Rabitz H. Role of potential structure in nonadiabatic collisions. PHYSICAL REVIEW. A, GENERAL PHYSICS 1987; 36:1124-1131. [PMID: 9898969 DOI: 10.1103/physreva.36.1124] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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120
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Guinzberg R, Laguna I, Zentella A, Guzman R, Piña E. Effect of adenosine and inosine on ureagenesis in hepatocytes. Biochem J 1987; 245:371-4. [PMID: 3663162 PMCID: PMC1148131 DOI: 10.1042/bj2450371] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Adenosine and inosine produced a dose-dependent stimulation of ureagenesis in isolated rat hepatocytes. Hypoxanthine, xanthine and uric acid were without effect. Half-maximally effective concentrations were 0.08 microM for adenosine and 5 microM for inosine. Activation of ureagenesis by both nucleosides had the following characteristics: (a) it was observed with either glutamine or (NH4)2CO3, provided that glucose was present; (b) it was not detected when glucose was replaced by lactate plus oleate; (c) it was mutually antagonized by glucagon, but not by adrenaline; and (d) it was dependent on Ca2+. We suggest that the action of adenosine and inosine on ureagenesis might be of physiological significance.
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121
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Diamond MC, Rainbolt RD, Guzman R, Greer ER, Teitelbaum S. Regional cerebral cortical deficits in the immune-deficient nude mouse: a preliminary study. Exp Neurol 1986; 92:311-22. [PMID: 3956664 DOI: 10.1016/0014-4886(86)90083-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
This report examines the morphology of the cerebral cortex in the nude mouse (nu/nu) compared with the BALB/c(+/+). Our experiments indicated that the thickness of the lateral frontal lobe was significantly reduced (8%; P less than 0.005) in the 4-month-old, female nude mouse compared with a BALB/c mouse of like sex and age. In addition, the left hemisphere was, in general, thinner in the nude than in the BALB/c, with area 18 being significantly thinner (2%; P less than 0.005). Oligodendrocytes were less in area 18 in the nude by 25% (P less than 0.02) in contrast to the BALB/c. In some respects these results extend the work of others. In previously published experiments, we showed that the thickness of the frontal cortex from enriched and impoverished female rats (from 60 to 116 days of age) differed by 2 to 3% (P less than 0.001) and in male rats by 3 to 4% (P less than 0.001). The oligodendrocytes in area 18 in the male differed by 20% (P less than 0.02) in rats exposed to their respective enriched or impoverished environments from 25 to 105 days of age. Thus, we have shown that the frontal cortical morphology as well as the occipital cortical oligodendrocytes were altered in both immune-deficient animals and environmentally stimulated or impoverished animals. Based on these separate sets of data, we will be interested to learn if our environmental conditions can alter the immune system and if so by what mechanism.
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122
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Richards J, Hamamoto S, Smith S, Pasco D, Guzman R, Nandi S. Response of end bud cells from immature rat mammary gland to hormones when cultured in collagen gel. Exp Cell Res 1983; 147:95-109. [PMID: 6352291 DOI: 10.1016/0014-4827(83)90274-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
End buds from 4- to 5-week-old rat mammary glands were isolated and cultured within a rat tail tendon collagen gel matrix. Media containing equine serum or porcine serum and cholera toxin promoted growth, but not the production of casein or thioesterase II, nor did they induce a state of differentiation as assessed by cell ultrastructure. Medium supplemented with only 5% porcine serum, insulin and cholera toxin did not support growth or differentiation. However, when prolactin, estradiol, progesterone and hydrocortisone were added to this medium, growth was stimulated greatly and a differentiated state was induced as assessed by the production of casein and thioesterase and by the appearance of a highly secretory ultrastructure.
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123
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Richards J, Pasco D, Yang J, Guzman R, Nandi S. Comparison of the growth of normal and neoplastic mouse mammary cells on plastic, on collagen gels and in collagen gels. Exp Cell Res 1983; 146:1-14. [PMID: 6861902 DOI: 10.1016/0014-4827(83)90319-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The growth of normal and neoplastic mouse mammary cells was compared in primary cultures on plastic, on rat tail collagen gels and in rat tail collagen gels. Cells on plastic grew for the first few days, then stopped with only a 1- to 3-fold increase in cell number after 2 weeks in culture. Cells grown on or in collagen gels grew continuously over the 2-week culture period with up to 10-fold increase in cell number for cultures on collagen gels and a 20-fold increase for cells embedded in collagen gels. The difference in growth rates between cells grown in collagen gel and those grown on collagen gels was due, in part, to the three-dimensional growth of the colonies in collagen gel their two-dimensional growth on collagen gel. Cells grown on and in collagen gel can produce an electron-dense basal lamina-like structure which is associated with collagen IV and laminin as judged by immunofluorescence. Cells grown on plastic do not form this structure. Cis-OH-proline blocks the production of collagen and inhibits the growth of the cultured cells indicating collagen production to be involved in growth. Rat tail collagen gels are a superior substratum for the growth of mouse mammary cells and this may be related to the cells' ability to form a collagen IV-containing basal lamina-like structure.
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Richards J, Guzman R, Konrad M, Yang J, Nandi S. Growth of mouse mammary gland end buds cultured in a collagen gel matrix. Exp Cell Res 1982; 141:433-43. [PMID: 6982824 DOI: 10.1016/0014-4827(82)90231-2] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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Rotman B, Guzman R. Identification of the mglA gene product in the beta-methylgalactoside transport system of Escherichia coli using plasmid DNA deletions generated in vitro. J Biol Chem 1982; 257:9030-4. [PMID: 6807987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Three genes (mglA, mglB, and mglC) required for active transport of substrate by the methylgalactoside permease were identified in a hybrid ColE1-DNA plasmid isolated from a clone (pLC3-14) of the Clarke-Carbon bank of Escherichia coli genes. A 4.6-kilobase DNA fragment obtained from pLC3-14 was cloned into the plasmid vector pBR322. The presence of the three mgl genes in the resultant plasmid, pMG3, was verified by genetic complementation and biochemical analysis of mgl mutants transformed with pMG3 DNA. Derivatives of pMG3 containing deletions in each mgl gene were constructed; restriction endonuclease mapping and functional analysis of these plasmids allowed us to physically locate the mgl genes within the inserted plasmid DNA and also to identify a heretofore unknown protein component of the transport system. Expression of these plasmids in vivo resulted in the specific synthesis of three major proteins of apparent molecular weight of 19,000, 36,000, and 52,000. The 36,000-dalton protein is the galactose-binding protein previously identified as the mglB product. The 19,000-dalton protein maybe the product of mglD, a regulatory gene mapping outside of the mgl gene cluster. The 52,000-dalton protein is a new permease component which we have identified here as the mglA product based on the observation that pMG6, a plasmid with a 0.6-kilobase mglA deletion, failed to encode for this protein but produced a truncated polypeptide showing a reduction in molecular weight comparable to the extent of the deletion. In bacteria bearing an mglA+, B-, C+ plasmid (Pmg4), the 52,000-dalton protein is located to a large extent (73%) in the membrane fraction.
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