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D Martin

Publications and source records attributed to D Martin.

At least 73 records · Page 4Linked to original sources
PubMed2001

West nile virus surveillance in Romania: 1997-2000.

In response to the 1996 West Nile (WN) fever epidemic that occurred in Bucharest and southeastern Romania, a surveillance program was established. The surveillance system detected 39 clinical human WN fever cases during the period 1997-2000: 14 cases in 1997, 5 cases in 1998, 7 cases in 1999, and 13 cases in 2000. Thirty-eight of the 39 case-patients lived in the greater Danube Valley of southern Romania, and 1 case-patient resided in the district of Vaslui, located on the Moldavian plateau. The estimated annual case incidence rate for the surveillance area during the period 1997-2000 was 0.95 cases per million residents. Thirty-four cases were serologically confirmed, and 5 cases were classified as probable. Twenty-four case-patients presented with clinical symptoms of meningitis (62%), 12 with meningoencephalitis (31%), 1 with encephalitis (3%), and 2 with febrile exanthema (5%). Five of the 39 cases were fatal (13%). Fourteen case-patients resided in rural areas, and 25 in urban and suburban areas, including 7 case-patients who resided in Bucharest. The ages of case-patients ranged from 8 to 76 years with a median age of 45 years. Twenty-four case-patients were males and 15 were females. Dates of onset of illness occurred from May 24 through September 25, with 82% of onset dates occurring in August and September. Limited entomological surveillance failed to detect WN virus. Retrospective sampling of domestic fowl in the vicinity of case-patient residences during the years 1997-2000 demonstrated seroprevalence rates of 7.8%-29%. Limited wild bird surveillance demonstrated seroprevalence rates of 5%-8%. The surveillance data suggest that WN virus persists focally for several years in poorly understood transmission cycles after sporadic introductions or that WN virus is introduced into Romania at relatively high rates, and persists seasonally in small foci.

Adolescent↗
PubMed2001

Clinical intestinal transplantation: a decade of experience at a single center.

OBJECTIVE: To assess the long-term efficacy of intestinal transplantation under tacrolimus-based immunosuppression and the therapeutic benefit of newly developed adjunct immunosuppressants and management strategies. SUMMARY BACKGROUND DATA: With the advent of tacrolimus in 1990, transplantation of the intestine began to emerge as therapy for intestinal failure. However, a high risk of rejection, with the consequent need for acute and chronic high-dose immunosuppression, has inhibited its widespread application. METHODS: During an 11-year period, divided into two segments by a 1-year moratorium in 1994, 155 patients received 165 intestinal allografts under immunosuppression based on tacrolimus and prednisone: 65 intestine alone, 75 liver and intestine, and 25 multivisceral. For the transplantations since the moratorium (n = 99), an adjunct immunosuppressant (cyclophosphamide or daclizumab) was used for 74 transplantations, adjunct donor bone marrow was given in 39, and the intestine of 11 allografts was irradiated with a single dose of 750 cGy. RESULTS: The actuarial survival rate for the total population was 75% at 1 year, 54% at 5 years, and 42% at 10 years. Recipients of liver plus intestine had the best long-term prognosis and the lowest risk of graft loss from rejection (P =.001). Since 1994, survival rates have improved. Techniques for early detection of Epstein-Barr and cytomegaloviral infections, bone marrow augmentation, the adjunct use of the interleukin-2 antagonist daclizumab, and most recently allograft irradiation may have contributed to the better results. CONCLUSION: The survival rates after intestinal transplantation have cumulatively improved during the past decade. With the management strategies currently under evaluation, intestinal transplant procedures have the potential to become the standard of care for patients with end-stage intestinal failure.

Adult↗
PubMed2001

Ten years of experience with the submental flap.

This article describes the authors' experience with the submental flap over the past 10 years. A brief review of the key points and some refinements in the operative technique are discussed. The results concern 31 patients with a mean age of 57 years. All flaps were pedicled except two. One case of composite flap with bone was used. The mean size of the flap was 11.8 x 5.5 cm, and the mean postoperative stay was 11.1 days. Complications encountered were one case of temporary palsy of the marginal mandibular branch of the facial nerve, one hematoma at the recipient site, and two cases of partial flap loss. Color and texture match were good. The authors believe this flap to have great clinical potential and to be a worthwhile addition to the existing surgical armamentarium.

Adult↗
PubMed2001

Internal use of n-butyl 2-cyanoacrylate (Indermil) for wound closure: an experimental study.

n-Butyl 2-cyanoacrylate glue (Indermil) was used for the closure of dorsal wounds on rabbits. A 4-cm-long and 1-cm-wide laceration was created bilaterally on the back of 15 rabbits. One side was closed with absorbable 2-0 subcutaneous sutures and fast absorbable 3-0 skin sutures, whereas the other side was closed with cyanoacrylate glue applied on both deep and superficial tissues. A partial wound dehiscence occurred on the glue side in one animal at 2 weeks. The animal was killed at this time and considered a bad result in the glue group. In all other animals, no seroma, partial dehiscence, or wound infection occurred. Histopathologic analysis revealed that Indermil induced edema and a mild acute inflammatory reaction and resorbed almost completely within 2 months when applied to well-vascularized tissues. The application of glue on the cutaneous wound edges is a fast and easy procedure that does not seem to delay or inhibit the healing process or its quality.

Animals↗
PubMed2001

EMF1, a novel protein involved in the control of shoot architecture and flowering in Arabidopsis.

Shoot architecture and flowering time in angiosperms depend on the balanced expression of a large number of flowering time and flower meristem identity genes. Loss-of-function mutations in the Arabidopsis EMBRYONIC FLOWER (EMF) genes cause Arabidopsis to eliminate rosette shoot growth and transform the apical meristem from indeterminate to determinate growth by producing a single terminal flower on all nodes. We have identified the EMF1 gene by positional cloning. The deduced polypeptide has no homology with any protein of known function except a putative protein in the rice genome with which EMF1 shares common motifs that include nuclear localization signals, P-loop, and LXXLL elements. Alteration of EMF1 expression in transgenic plants caused progressive changes in flowering time, shoot determinacy, and inflorescence architecture. EMF1 and its related sequence may belong to a new class of proteins that function as transcriptional regulators of phase transition during shoot development.

Amino Acid Sequence↗
PubMed2001

Localization of surface immunogenic protein on group B streptococcus.

The localization and accessibility of the group B streptococcus (GBS) surface immunogenic protein (Sip) at the surface of intact GBS cells were studied by flow cytometric assay and immunogold electron microscopy. Antibodies present in pooled sera collected from mice after immunization with purified recombinant Sip efficiently recognized native Sip at the surfaces of the different GBS strains tested, which included representatives of all nine serotypes. Examination of GBS cells by immunogold electron microscopy revealed that the Sip-specific antibodies attached preferentially to polar sites and the septal region. This result confirmed that Sip is exposed at the intact-cell surface, but it also suggests that its distribution is restricted to certain regions of the cell.

Animals↗
PubMed2001

A multilevel analysis of the effects of rurality and social deprivation on premature limiting long term illness.

STUDY OBJECTIVE: To examine the geographical variation in self perceived morbidity in the south west of England, and assess the associations with rurality and social deprivation. DESIGN: A geographically based cross sectional study using 1991 census data on premature Limiting Long Term Illness (LLTI). The urban-rural and intra-rural variation in standardised premature LLTI ratios is described, and correlation and regression analyses explore how well this is explained by generic deprivation indices. Multilevel Poisson modelling investigates whether Customized Deprivation Profiles (CDPs) and area characteristics improve upon the generic indices. SETTING: Nine counties in the south west of England PARTICIPANTS: The population of the south west enumerated in the 1991 census. MAIN RESULTS: Intra-rural variation is apparent, with higher rates of premature LLTI in remoter areas. Together with high rates in urban areas and lower rates in the semi-rural areas this indicates the existence of a U shaped relation with rurality. The generic deprivation indices have strong positive relations with premature LLTI in urban areas, but these are a lot weaker in semi-rural and rural locations. CDPs improve upon the generic indices, especially in the rural settings. A substantial reduction in unexplained variation in rural areas is seen after controlling for the level of local isolation, with higher isolation, at the wider geographical scale, being related to higher levels of LLTI. CONCLUSIONS: This study highlights the need to treat rural areas as heterogeneous, although this has not been the tendency in health research. Generic deprivation indices are unlikely to be a true reflection of levels of deprivation in rural environments. The importance of CDPs that are specific to the area type and health outcome is emphasised. The significance of physical isolation suggests that accessibility to public and health services may be an important issue, and requires further research.

Adolescent↗
PubMed2001

Nifedipine-activated Ca(2+) permeability in newborn rat cortical collecting duct cells in primary culture.

To characterize Ca(2+) transport in newborn rat cortical collecting duct (CCD) cells, we used nifedipine, which in adult rat distal tubules inhibits the intracellular Ca(2+) concentration ([Ca(2+)](i)) increase in response to hormonal activation. We found that the dihydropyridine (DHP) nifedipine (20 microM) produced an increase in [Ca(2+)](i) from 87.6 +/- 3.3 nM to 389.9 +/- 29.0 nM in 65% of the cells. Similar effects of other DHP (BAY K 8644, isradipine) were also observed. Conversely, DHPs did not induce any increase in [Ca(2+)](i) in cells obtained from proximal convoluted tubule. In CCD cells, neither verapamil nor diltiazem induced any rise in [Ca(2+)](i). Experiments in the presence of EGTA showed that external Ca(2+) was required for the nifedipine effect, while lanthanum (20 microM), gadolinium (100 microM), and diltiazem (20 microM) inhibited the effect. Experiments done in the presence of valinomycin resulted in the same nifedipine effect, showing that K(+) channels were not involved in the nifedipine-induced [Ca(2+)](i) rise. H(2)O(2) also triggered [Ca(2+)](i) rise. However, nifedipine-induced [Ca(2+)](i) increase was not affected by protamine. In conclusion, the present results indicate that 1) primary cultures of cells from terminal nephron of newborn rats are a useful tool for investigating Ca(2+) transport mechanisms during growth, and 2) newborn rat CCD cells in primary culture exhibit a new apical nifedipine-activated Ca(2+) channel of capacitive type (either transient receptor potential or leak channel).

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed2001

Exhaled nitric oxide correlated with induced sputum findings in COPD.

STUDY OBJECTIVES: Neutrophilic airway inflammation may underlie the pathogenesis of COPD. We examined repeated measurements of the fractional concentration of exhaled nitric oxide (FENO) and the correlation with cells and mediators in induced sputum (IS) from patients with COPD. PARTICIPANTS: Eleven COPD subjects (9 men and 2 women, aged 46 to 69 years) with predicted FEV(1) of 45 to 70%. SETTING: A hospital research laboratory. DESIGN: Single-cohort, prospective study with four visits at two weekly intervals. INTERVENTIONS: FENO and spirometry were assessed at all visits, and IS for differential cell count, leukotriene-B(4) (LTB(4)) and interleukin (IL)-8, nitrite, and nitrate at visit 1, visit 3, and visit 4. RESULTS: During the study, there were significant declines in mean percent predicted FEV(1), from 55.2 to 51.6% (p = 0.029), and mean FEV(1)/FVC ratio, from 50.4 to 45.4% (p = 0.001), accompanied by a significant increase in FENO geometric mean (95% confidence limits), from 15.2 (10.9 to 21.2) to 23.6 (17.1 to 32.4) parts per billion (p = 0.037), and sputum LTB(4), from 1.79 (1.03 to 3.11) to 3.57 (1.95 to 6.53) ng/mL (p = 0.033), but no significant change in other sputum parameters. From visits 1 to 4, the change in percent neutrophils correlated with the changes in FENO and IL-8 (r = 0.648, p = 0.028; r = 0.60, p = 0.05, respectively). Hypertonic saline solution induction of sputum caused a fall in FEV(1), from 1.83 +/- 0.44 to 1.46 +/- 0.44 L (p = 0.049). CONCLUSIONS: The worsening spirometry results were accompanied by significant increases in FENO and sputum LTB(4). FENO may be related to neutrophilic inflammation driven by the chemoattractant IL-8. FENO and IS may be useful markers of airway inflammation in COPD patients. Sputum induction with hypertonic saline solution causes a significant fall in FEV(1) requiring appropriate caution.

Aged↗
PubMed2001

A comparative statistical analysis of neuronavigation systems in a clinical setting.

The use of neuronavigation (NN) in neurosurgery has become ubiquitous. A growing number of neurosurgeons are utilizing NN for a wide variety of purposes, including optimizing the surgical approach (macrosurgery) and locating small areas of interest (microsurgery). The goal of our team is to apply rapid advances in hardware and software technology to the field of NN, challenging and ultimately updating current NN assumptions. To identify possible areas in which new technology may improve the surgical applications of NN, we have assessed the accuracy of neuronavigational measurements in the Radionics and BrainLab systems. Using a phantom skull, we measured how accurate the visualization of a navigational probe's tip was in these systems, taking a total of 2180 measurements. We found that, despite current NN tenets, error is maximal at the six marker count and minimal in the spreaded marker setting; that is, placing less markers around the area of interest maximizes accuracy and active tracking does not necessarily increase accuracy. Comparing the two systems, we also found that accuracy of NN machines differs both overall and in different axes. As researchers continue to apply technological advances to the NN field, an increasing number of currently held tenets will be revised, making NN an even more useful tool in neurosurgery.

Factor Analysis, Statistical↗
PubMed2001

Neuronavigational epilepsy focus mapping.

The localization of a seizure focus for resective surgery often requires invasive monitoring for precise localization of the target as well as structures to avoid. We report on the use of intra-operative surgical navigation to precisely localize and co-register subdural electrodes to regions of know radiographic pathology. Additionally, the navigation system was used to develop intra-operative electrode maps. These maps were subsequently used in the sub-acute recording phase to assign electrographic pathology and function (e.g. speech) to a specific cortical surface anatomy. This permitted for more precise planning of surgery and better assessment of potential risk, based on functional as well as anatomical criterion.

Artificial Intelligence↗
PubMed2001

The submental flap: its uses as a pedicled or free flap for facial reconstruction.

The submental flap is an alternative to microsurgical flaps for facial and intraoral defects. The submental flap is simple and can be raised rapidly. It produces good color, texture, and contour match without a conspicuous site. Its versatility and its rotational arc explains its large application in facial surgery. The pedicle is reliable when the flap is not used with a reverse flow. The surgeon must know the possible presence of valves in the venous system of the face and plan to perform a venous microsurgical anastomosis if venous congestion jeopardizes the flap's survival. The location of the flap in a lymph node area restricts its uses for traumatic cases, and for benign and malignant tumors, to reduce the potential of cancer spreading to the lymph nodes (e.g., basal cell carcinoma).

Aged↗
PubMed2001

[Comparison of MRA and angiography in the follow-up of intracranial aneurysms treated with GDC].

OBJECTIVE: Evaluation of TOF 3D MRA compared to angiography in the follow-up of intracranial aneurysms treated by Guglielmi detachable coils (GDC). MATERIAL: and method: Prospective analysis of follow-up MRA and angiographies for 20 patients with 22 aneurysms. There were 2 MRAs for 3 aneurysms giving a total of 25 cases. RESULTS: A poor correlation between MRA and angiography was observed in 21 cases of 25. For 9 cases, stable exclusion (95-100%) visible on MRA was confirmed by angiography. For 12 other cases, a residual flow within the aneurysmal neck or a residual flow between coils was detected by MRA and confirmed by angiography. A poor correlation was found in 4 cases out of 25: 3 residual flows within the aneurysmal neck and 1 residual flow within the coil mass not visible on MRA. MRA has a sensibility of 75% for the detection of an anomaly, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 69.2%. MRA is able to detect a large residual flow within aneurysmal neck and a re-growth, which would need a second embolization. Anomalies not visible on MRA as observed in our study, residual flow within the coil mass and the aneurysmal neck, do not require complementary treatment. CONCLUSION: A normal TOF 3D MRA can avoid an angiography in the follow-up of an intracranial aneurysm treated by GDC.

Adult↗
PubMed2001

[MRI screening of vestibular schwannomas without gadolinium: usefulness of the turbo gradient spin echo T2-weighted pulse sequence].

The purpose of this retrospective MRI work was to evaluate the use of turbo gradient spin echo (TGSE) high resolution imaging for the detection of eighth nerve schwannomas, without injection of gadolinium. The TGSE sequence (slice thickness: 3 mm with 1.5 mm interleaving; matrix: 512) was compared with a reference sequence: T1-weighted spin echo (SE) after gadolinium injection (slice thickness: 3 mm, matrix: 256). Among 380 internal auditory meatus (IAM) explored, 34 abnormalities were detected on T2-weighted TGSE images compared with 19 on contrast-enhanced T1-weighted SE images. This new sequence has a 100% sensitivity, a 96% specificity and a 100% negative predictive value. Using a rigorous protocol for IAM analysis with the TGSE sequence, gadolinium injection may no longer be needed systematically for vestibular schwannoma screening, but might only be necessary when an abnormality or a doubt persists after TGSE. This approach allows about 20% cost reduction for each patient, a savings of 11,433 euros considering only the true negatives observed in this study.

Adolescent↗
PubMed2001

Proinflammatory cytokine expression contributes to brain injury provoked by chronic monocyte activation.

BACKGROUND: We have proposed that an increased interaction between monocyte/macrophages and blood vessel endothelium predisposes subjects to strokes. The effect of chronic monocyte activation on the development of cerebral infarcts was thus studied in rats after provocation of a modified local Swartzman reaction, in brain vasculature. MATERIALS AND METHODS: Two weeks after an IV bolus of bacillus Calmette-Guérin (BCG), we studied spontaneous superoxide production, integrin expression, endothelial adhesion of monocytes and the neurological symptoms, brain histology, and cytokine immunoreactivity after a provocative dose of LPS (30-300 microg/rat i.c.v.). RESULTS: Monocyte migration into the brain was stimulated by BCG priming. The incidence of paralysis and death in response to LPS was markedly increased in BCG-primed rats. Histological evaluation of the brains of neurologically impaired and moribund animals revealed intravascular thrombosis and pale and hemorrhagic infarcts. Infiltrates of leukocytes expressing immunoreactive IL-1:, IL-6, and TNF-alpha were found around blood vessels, cerebral ventricles, and meninges, and were accompanied by a profound microglial expression of IL1P, endothelial expression of IL-6, and expression of TNF-alpha and TNF-R 1 in glia and neurons of cortex and hippocampus. Treatment (2 x 100 microg/10 ,I, i.c.v.) with recombinant human (rh-)TNF 55kDa receptor completely prevented, and treatment with rh-IL- I receptor antagonist significantly decreased the incidence of paralysis and death in response to BCG + LPS. The improvement of neurological symptoms was accompanied by reduced histological damage and supppression of IL-1P/ expression in the brain tissue. CONCLUSIONS: The data demonstrate that chronic monocyte activation predisposes subjects to thrombosis and hemorrhage via an exaggerated release of proinflammatory cytokines.

Adjuvants, Immunologic↗
PubMed2001

[How I treat ... refractory epilepsy by vagal nerve stimulation].

Intermittent left vagus nerve stimulation is a novel therapeutic modality that can be proposed to patients with a refractory epilepsy and for whom resective surgery is not an option. Its precise mechanism of action is not known. Controlled studies have shown that its efficacy is similar to that of antiepileptic drugs: 50% decrease in seizure frequency in 40% patients after two years. Side effects which are generally mild to moderate are the result of a diffusion of the stimulation to the larynx. No CNS side effect has been reported.

Drug Resistance↗
PubMed2001

Moulds, moisture and microbial contamination of First Nations housing in British Columbia, Canada.

This paper reviews the difficulties experienced with mould growth in First Nations homes in British Columbia and to describe the team approach used in dealing with this problem. Humid, damp conditions promote the growth of bacteria, moulds, and dust mites. These organisms contribute to poor air quality and causes serious health problems. There is increasing evidence indicating an association between mould, particularly toxigenic moulds, and some diseases, notably asthma. These health problems usually improve when families are relocated to more suitable accommodation. Those particularly at risk include atopic, immunocompromised, very young and elderly individuals and those with chronic health conditions. Our experience suggests that substandard housing is a major contributor to poor health in First Nations communities.

Air Pollution, Indoor↗