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T McNamara

Publications and source records attributed to T McNamara.

At least 19 recordsLinked to original sources
PubMed2002

Inhibition of proteolytic, serpinolytic, and progelatinase-b activation activities of periodontopathogens by doxycycline and the non-antimicrobial chemically modified tetracycline derivatives.

BACKGROUND: Tetracyclines, particularly doxycycline (Doxy), and their non-antimicrobial chemically-modified derivatives (CMTs) inhibit the activities of human matrix metalloproteinases (MMPs), and reduce the severity and progression of periodontal disease in animal models and humans. In this study, the effects of Doxy and CMT-1, -3, and -5 on proteolytic, serpinolytic, and progelatinase-B activation activities of potent periodontopathogens were studied. METHODS: The effect of Doxy and CMTs (0.5 to 50 microM) on proteolytic activities were investigated by incubating bacteria with chromogenic substrates or human serum albumin. A collagenolytic fraction of Porphyromonas gingivalis was used to evaluate the effect of these substances on collagenolytic (type I collagen) and serpinolytic (alpha1-proteinase inhibitor) activities. Lastly, the effect of Doxy on progelatinase-B (pro-MMP-9) activation by purified proteinases from P. gingivalis and Treponema denticola was investigated by SDS-PAGE/Western immunoblotting. RESULTS: Doxy and CMTs, except CMT-5 which lacks the structural elements required for cation chelation, inhibited Arg- and Lys-gingipain activities as well as collagenolytic activity of P. gingivalis. Doxy and CMTs did not markedly affect the chymotrypsin-like activity of T. denticola but inhibited its trypsin-like activity. In addition, degradation of human serum albumin by cells of P. gingivalis and T. denticola was strongly inhibited by Doxy and CMT-1. Doxy and CMT-1 also inhibited the inactivation of alpha1-proteinase inhibitor (serpinolytic activity) by a collagenolytic fraction of P. gingivalis. Lastly, Doxy prevented the latent to active conversion of human neutrophil progelatinase-B (pro-MMP-9) by Arg-gingipains A/B of P. gingivalis but not by the chymotrypsin-like proteinase of T. denticola. CONCLUSIONS: Data from this study suggest that Doxy and CMTs have the potential to inhibit the periodontopathogenic bacterial proteinases, which contribute to tissue destruction cascades during periodontitis directly and indirectly by triggering the host response.

Adhesins, Bacterial↗
PubMed1999

Origin of the West Nile virus responsible for an outbreak of encephalitis in the northeastern United States.

In late summer 1999, an outbreak of human encephalitis occurred in the northeastern United States that was concurrent with extensive mortality in crows (Corvus species) as well as the deaths of several exotic birds at a zoological park in the same area. Complete genome sequencing of a flavivirus isolated from the brain of a dead Chilean flamingo (Phoenicopterus chilensis), together with partial sequence analysis of envelope glycoprotein (E-glycoprotein) genes amplified from several other species including mosquitoes and two fatal human cases, revealed that West Nile (WN) virus circulated in natural transmission cycles and was responsible for the human disease. Antigenic mapping with E-glycoprotein-specific monoclonal antibodies and E-glycoprotein phylogenetic analysis confirmed these viruses as WN. This North American WN virus was most closely related to a WN virus isolated from a dead goose in Israel in 1998.

Amino Acid Sequence↗
PubMed1999

For whom is the Caesarean section rate high?

AIM: To define a method for examining and comparing Caesarean section rates. METHODS: Data on Caesarean section rates at National Women's Hospital for 1997 were analysed by two methods which adjust Caesarean section rates according to casemix: 1. standard nulliparae and 2. grouping women by factors influencing Caesarean section rates. RESULTS: The Caesarean section rate in New Zealand is rising and National Women's Hospital had a Caesarean section rate of 22.3% in 1997. The instrumental vaginal delivery rate was 13.1%. Our 1997 data were analysed for casemix -- standard nulliparae and dividing women into six distinct groups. The Caesarean section rate for standard nulliparae was 19.2%. Nulliparae had an increased induction of labour rate compared to multiparae (29.1% versus 22.9%, p < 0.001). The Caesarean section rate was increased in association with induction of labour for nulipare (26.0% versus 13.1%, p < 0.001), multiparae with unscarred uteri, (5.4% versus 2.5%, p < 0.001) and primiparae with previous caesareans (36.8% versus 30.4%, p = 0.02) CONCLUSION: We suggest our second method of grouping women by the most important factors influencing intervention rates should be used by obstetric units for benchmarking and internal audit purposes.

Adult↗
PubMed1999

Predictors of outcome among patients with class II division 1 malocclusion treated with fixed appliances in the permanent dentition.

This retrospective study investigated the outcomes achieved in 212 consecutively completed patients with Class II Division 1 malocclusion (overjet > 6 mm). All patients were treated in the permanent dentition with upper and lower fixed appliances. A composite outcome measure was used to identify those cases with an excellent outcome (posttreatment PAR </= 5, posttreatment upper incisor to maxillary plane angle between 104.7 degrees and 115.3 degrees, and anterior movement of the lower incisors </= 2 mm). Logistic regression analysis with patient group as the dependent variable was used to evaluate the predictive value of 32 patient and treatment variables. The three outcome measures (posttreatment PAR score, posttreatment upper incisor inclination, and anterior movement of lower incisors) were ranked and combined to form a single continuous outcome variable. This was used as the dependent variable to carry out further analysis with the linear regression method. Both methods of analysis identified pretreatment overjet and pretreatment upper incisor inclination as significant predictors of outcome. The results revealed that in patients with large overjets an excellent outcome can only be predicted if the upper incisors are very proclined. Every 2 mm increase in overjet (above 4 mm) required approximately a 5 degrees increase in incisor proclination to achieve an excellent outcome.

Adolescent↗
PubMed1999

Herpesvirus-associated papillomas in koi carp (Cyprinus carpio).

From January through November 1994, 32% (7/22) of koi carp (Cyprinus carpio) maintained in indoor aquariums developed proliferative cutaneous lesions that consisted of single to multiple 2-10-mm whitish to pink fleshy masses usually associated with fin rays. Although scaleless koi were more commonly affected (3/6) than were normally scaled koi (4/16), the difference in incidence rates was not significant (chi2 text, P > 0.05). Lesions typically resolved spontaneously in 1-3 wk, occasionally persisted for >3 mo, and recurred in several fish after 2-5 mo. Fish were otherwise asymptomatic. Wet mount preparations from lesions were densely cellular and consisted of hyperplastic epidermal cells of normal morphology without parasites or inflammatory cells. Histologically, biopsies were consistent with papillomas and were characterized by a marked benign epidermal hyperplasia without inclusion bodies or inflammatory infiltrate. Transmission electron microscopic examination revealed intranuclear and intracytoplasmic herpesvirus virions. Virus isolation attempts were unsuccessful.

Animals↗
PubMed1998

Treatment outcome for a sample of patients with Class II division 1 malocclusion treated at a regional hospital orthodontic department.

This retrospective study assessed the outcome of orthodontic treatment of 264 patients with Class II division 1 malocclusion (overjet greater than 6 mm). The sample comprised patients who had completed their fixed appliance orthodontic treatment at a regional hospital orthodontic unit in the Republic of Ireland. The PAR Index (Peer Assessment Rating) was used to evaluate treatment outcome using before and after treatment study casts. The results revealed that treatment for this particular type of malocclusion was highly effective with a very few patients failing to benefit from their orthodontic treatment.

Adolescent↗
PubMed1997

Facial talon cusps.

This is a report of two patients with isolated facial talon cusps. One occurred on a permanent mandibular central incisor; the other on a permanent maxillary canine. The locations of these talon cusps suggests that the definition of a talon cusp include teeth in addition to the incisor group and be extended to include the facial aspect of teeth.

Adolescent↗
PubMed1997

Beckwith-Wiedemann syndrome: dental management.

Beckwith-Wiedemann syndrome (BWS) comprises multiple congenital anomalies with a risk of childhood tumours. Macroglossia is the most common manifestation. Two cases are presented to illustrate the importance of early referral and the role of preventive dentistry.

Beckwith-Wiedemann Syndrome↗