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Tony Mazzulli

Publications and source records attributed to Tony Mazzulli.

At least 37 records · Page 2Linked to original sources
PubMed2004

Use of the Vitek-1 and Vitek-2 systems for detection of constitutive and inducible macrolide resistance in group B streptococci.

A prospective study of erythromycin and clindamycin resistance was performed with 304 consecutive group B streptococci (GBS) isolates. According to two automated susceptibility testing systems, Vitek-1 and Vitek-2, and double-disk agar diffusion, 79.9% were susceptible to both erythromycin and clindamycin. However, for macrolide-lincosamide-streptogramin B-inducible isolates, the accuracies of the Vitek-1 and Vitek-2 systems were 5.6 and 94.4%. In light of these results, we recommend that GBS be routinely tested using the double-disk diffusion method.

Clindamycin↗
PubMed2004

Severe acute respiratory syndrome-associated coronavirus in lung tissue.

Efforts to contain severe acute respiratory syndrome (SARS) have been limited by the lack of a standardized, sensitive, and specific test for SARS-associated coronavirus (CoV). We used a standardized reverse transcription-polymerase chain reaction assay to detect SARS-CoV in lung samples obtained from well-characterized patients who died of SARS and from those who died of other reasons. SARS-CoV was detected in all 22 postmortem lung tissues (to 10(9) viral copies/g) from 11 patients with probable SARS but was not detected in any of the 23 lung control samples (sample analysis was blinded). The sensitivity and specificity (95% confidence interval) were 100% (84.6% to 100%) and 100% (85.1% to 100%), respectively. Viral loads were significantly associated with a shorter course of illness but not with the use of ribavirin or steroids. CoV was consistently identified in the lungs of all patients who died of SARS but not in control patients, supporting a primary role for CoV in deaths.

Adult↗
PubMed2004

Severe acute respiratory syndrome: overview with an emphasis on the Toronto experience.

OBJECTIVE: To provide an overview of the severe acute respiratory syndrome (SARS) outbreak in Toronto, Ontario, which experienced the largest outbreak outside Asia, and to review what has been learned during the past year. DATA SOURCES: MEDLINE search of all studies related to SARS, including review of the Centers for Disease Control and Prevention, World Health Organization (WHO), and Health Canada Web sites. DATA SYNTHESIS: During the SARS outbreak in Toronto, 438 people had been diagnosed as having suspected or probable SARS and 44 people died. Elderly people and those with comorbid illnesses were at greatest risk of complications or death. Transmission was via direct contact with respiratory secretions. The use of gloves, gowns, N95 masks, and eye protection was effective in preventing transmission. No transmission occurred before symptom onset or after recovery. Serologic tests suggest that antibodies may not appear until 28 days after illness onset. Molecular tests give their greatest yield during the second week of illness. The value of ribavirin treatment remains questionable. The combination of interferon plus corticosteroids appears to be better than corticosteroids alone. Postmortem examination revealed pulmonary edema and evidence of diffuse alveolar damage. Very few morphological changes were noted in other organs despite the presence of viral RNA as detected by polymerase chain reaction. CONCLUSION: On July 5, 2003, the WHO declared that the SARS outbreak was over. Since then, new cases of SARS have been reported in Asia. With global travel, the disease can rapidly spread throughout the world. Therefore, we must remain vigilant to prevent another pandemic.

Animals↗
PubMed2003

Relation between apolipoprotein E genotype, hepatitis B virus status, and thyroid status in a sample of older persons with Down syndrome.

Dementia of the Alzheimer type (DAT) is common in older persons with Down syndrome (DS). There are three common alleles of the apolipoprotein E (ApoE) gene (Sigma 2, Sigma 3, and Sigma 4) resulting in three different isoforms (E2, E3, and E4) and six different genotypes (2,2; 2,3; 2,4; 3,3; 3,4; and 4,4). Sigma 4 is a risk factor for DAT whereas Sigma 2 appears prophylactic. As hepatitis B virus (HBV) infection and hypothyroidism also are common in DS, we evaluated associations between ApoE type, HBV status, and thyroid status in a sample of older persons with DS (n = 55; mean age, 44.3 +/- 10.8 years) using chi-squared analysis. Participants were classified as E2 (2,2 or 2,3), E3 (3,3), or E4 (3,4 or 4,4); positive for markers of HBV infection in the present or past (i.e., total HBcAb+ and/or HBsAg+ with or without infectivity, defined as HBV+) or negative for markers of HBV infection (defined as HBV-) and, currently receiving thyroid hormone supplement (defined as "hypothyroidism") or having normal thyroid function. The majority of the HBV+ were currently HBcAb+ and HBsAb+, but not HBsAg+. In females, there was an ApoE allele effect on thyroid status (P < or = 0.01), E2 being negatively (P < or = 0.01) and E4 being positively (P < or = 0.05) associated with "hypothyroidism". There was no evidence for an ApoE allele effect on thyroid status in males. There was no evidence for an ApoE allele effect on HBV status, or for an HBV status effect on thyroid status. As thyroid status can affect cognitive function, ApoE allele effects in DAT may, in part, be thyroid effects.

Adult↗
PubMed2003

West Nile virus infection in 2002: morbidity and mortality among patients admitted to hospital in southcentral Ontario.

BACKGROUND: In August and September 2002 an outbreak of West Nile virus (WNV) infection occurred in southern Ontario. We encountered a number of seriously ill patients at our hospitals. In this article we document the clinical characteristics of these cases. METHODS: We conducted a retrospective chart review of patients who came to the attention of infectious disease or neurology consultants or the microbiology laboratories at 7 hospitals in the municipalities of Toronto, Peel and Halton, Ont. Patients were included if they had been admitted to hospital or stayed overnight in the emergency department, had serological evidence of WNV infection and had clinical evidence of WNV fever, aseptic meningitis, encephalomyelitis or motor neuronopathy. RESULTS: In all, 64 patients met the inclusion criteria; 57 had encephalitis or neuromuscular weakness or both, 5 had aseptic meningitis, and 2 had WNV fever. The mean age was 61 years (range 26-87). The patients were predominantly active, middle-aged or elderly people living independently in the community. Seven patients were immunocompromised A febrile prodromal illness preceded the neurological symptoms in almost all cases. The most common neurological abnormality was decreased level of consciousness; this frequently evolved to severe lower motor neuron neuromuscular weakness. Ataxia and swallowing disorders were frequent and important problems. Sixteen patients (25%) required intubation and mechanical ventilation because of a decreased level of consciousness, inability to clear secretions or respiratory muscle weakness; 9 others had disabling muscle weakness of one or more limbs. Ten patients died. The study patients were in hospital a total of 1856 patient-days, including 532 patient-days in an intensive care unit. Only 28% (13/47) of the patients who survived encephalitis or neuromuscular weakness, or both, were discharged home without additional support. Slow turnaround time for serological test results resulted in delayed diagnosis. INTERPRETATION: The 2002 WNV infection outbreak in Ontario caused serious morbidity and mortality in the subset of patients who had encephalitis or neuromuscular weakness severe enough to require hospital admission.

Adult↗
PubMed2003

The immediate psychological and occupational impact of the 2003 SARS outbreak in a teaching hospital.

BACKGROUND: The outbreak of severe acute respiratory syndrome (SARS) in Toronto, which began on Mar. 7, 2003, resulted in extraordinary public health and infection control measures. We aimed to describe the psychological and occupational impact of this event within a large hospital in the first 4 weeks of the outbreak and the subsequent administrative and mental health response. METHODS: Two principal authors met with core team members and mental health care providers at Mount Sinai Hospital, Toronto, to compile retrospectively descriptions of the experiences of staff and patients based on informal observation. All authors reviewed and analyzed the descriptions in an iterative process between Apr. 3 and Apr. 13, 2003. RESULTS: In a 4-week period, 19 individuals developed SARS, including 11 health care workers. The hospital's response included establishing a leadership command team and a SARS isolation unit, implementing mental health support interventions for patients and staff, overcoming problems with logistics and communication, and overcoming resistance to directives. Patients with SARS reported fear, loneliness, boredom and anger, and they worried about the effects of quarantine and contagion on family members and friends. They experienced anxiety about fever and the effects of insomnia. Staff were adversely affected by fear of contagion and of infecting family, friends and colleagues. Caring for health care workers as patients and colleagues was emotionally difficult. Uncertainty and stigmatization were prominent themes for both staff and patients. INTERPRETATION: The hospital's response required clear communication, sensitivity to individual responses to stress, collaboration between disciplines, authoritative leadership and provision of relevant support. The emotional and behavioural reactions of patients and staff are understood to be a normal, adaptive response to stress in the face of an overwhelming event.

Anti-Inflammatory Agents↗
PubMed2003

Clinical features and short-term outcomes of 144 patients with SARS in the greater Toronto area.

CONTEXT: Severe acute respiratory syndrome (SARS) is an emerging infectious disease that first manifested in humans in China in November 2002 and has subsequently spread worldwide. OBJECTIVES: To describe the clinical characteristics and short-term outcomes of SARS in the first large group of patients in North America; to describe how these patients were treated and the variables associated with poor outcome. DESIGN, SETTING, AND PATIENTS: Retrospective case series involving 144 adult patients admitted to 10 academic and community hospitals in the greater Toronto, Ontario, area between March 7 and April 10, 2003, with a diagnosis of suspected or probable SARS. Patients were included if they had fever, a known exposure to SARS, and respiratory symptoms or infiltrates observed on chest radiograph. Patients were excluded if an alternative diagnosis was determined. MAIN OUTCOME MEASURES: Location of exposure to SARS; features of the history, physical examination, and laboratory tests at admission to the hospital; and 21-day outcomes such as death or intensive care unit (ICU) admission with or without mechanical ventilation. RESULTS: Of the 144 patients, 111 (77%) were exposed to SARS in the hospital setting. Features of the clinical examination most commonly found in these patients at admission were self-reported fever (99%), documented elevated temperature (85%), nonproductive cough (69%), myalgia (49%), and dyspnea (42%). Common laboratory features included elevated lactate dehydrogenase (87%), hypocalcemia (60%), and lymphopenia (54%). Only 2% of patients had rhinorrhea. A total of 126 patients (88%) were treated with ribavirin, although its use was associated with significant toxicity, including hemolysis (in 76%) and decrease in hemoglobin of 2 g/dL (in 49%). Twenty-nine patients (20%) were admitted to the ICU with or without mechanical ventilation, and 8 patients died (21-day mortality, 6.5%; 95% confidence interval [CI], 1.9%-11.8%). Multivariable analysis showed that the presence of diabetes (relative risk [RR], 3.1; 95% CI, 1.4-7.2; P =.01) or other comorbid conditions (RR, 2.5; 95% CI, 1.1-5.8; P =.03) were independently associated with poor outcome (death, ICU admission, or mechanical ventilation). CONCLUSIONS: The majority of cases in the SARS outbreak in the greater Toronto area were related to hospital exposure. In the event that contact history becomes unreliable, several features of the clinical presentation will be useful in raising the suspicion of SARS. Although SARS is associated with significant morbidity and mortality, especially in patients with diabetes or other comorbid conditions, the vast majority (93.5%) of patients in our cohort survived.

Adult↗
PubMed2003

Effects of low-level laser therapy (LLLT) of 810 nm upon in vitro growth of bacteria: relevance of irradiance and radiant exposure.

OBJECTIVE: The aim of this study was to investigate the irradiance-dependency of low-level laser therapy (LLLT) effects on bacterial growth. BACKGROUND: LLLT is applied to open wounds to improve healing; however, its effect on wound bacteria is not well understood. MATERIALS AND METHODS: Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus were irradiated using a wavelength of 810 nm at irradiances of 0.015 W/cm2 (0-50 J/cm2) and 0.03 W/cm2 (0-80 J/cm2). Bacteria were counted after 20 h of incubation. RESULTS: LLLT effects varied significantly with species. P.aeruginosa growth decreased overall dependent on an interaction of irradiance and radiant exposure; greatest inhibition was produced using high irradiance delivering radiant exposures in the range of 1-20 J/cm2 (p = 0.001-0.04). In contrast, E. coli growth increased overall (p = 0.01), regardless of irradiance; greatest effects were produced using low radiant exposures (1-20 J/cm2). There was a main effect for irradiance (p = 0.03) on S. aureus growth; however, growth was not different compared with controls. Additional analysis showed that there were differences in growth of P.aeruginosa when comparing samples that were matched by exposure times (66, 329, 658, 1316, 1974, and 2632 sec) rather than radiant exposure; this suggests that irradiance rather than exposure time was the significant factor in P. aeruginosa inhibition. CONCLUSION: These findings have immediate relevancy in the use of LLLT for infected wounds. Exposure to 810-nm irradiation (0.03 W/cm2) could potentially benefit wounds infected with P. aeruginosa. However, increased E. coli growth could further delay recovery.

Bacteria↗
PubMed2003

Allergic fungal sinusitis associated with Trichoderma longibrachiatum.

We describe allergic fungal sinusitis caused by Trichoderma longibrachiatum in a patient with a history of atopy and asthma. A Gram stain of a sinus biopsy specimen was initially thought to contain yeast cells, but when Trichoderma was recovered in culture, these cells were subsequently recognized as chlamydospores. The patient was successfully managed with a combination of sinus lavage, oral corticosteroids, itraconazole, and allergen immunotherapy. This case also points out that careful scrutiny of direct smears is required to ensure that fungal structures are not misinterpreted.

Adrenal Cortex Hormones↗
PubMed2003

Early prediction of nonresponders to treatment with interferon alpha-2b and ribavirin in patients with chronic hepatitis C.

BACKGROUND: Treatment of chronic hepatitis C virus (HCV) infection with interferon alpha-2b and ribavirin is costly in terms of side effects, medical resources and drug costs. Furthermore, less than 50% of patients overall have a sustained virological response (SVR). OBJECTIVE: To determine if the log fall in HCV RNA between baseline and week 1 (b-wk1) and between baseline and week 4 (b-wk4) after starting treatment could identify the nonresponders. PATIENTS AND METHODS: Sixty-three patients who had completed a full course of therapy were identified. Quantitative measurements of HCV RNA were analyzed from stored sera, collected prospectively. RESULTS: SVR was achieved in 47.1% and 47.3% of patients in the b-wk1 and b-wk4 groups, respectively. No patients had an SVR with a fall in HCV RNA of less than 0.35 log10 and 1.05 log10 at week 1 and week 4, respectively. This accounted for 44.4% and 51.7% of the nonresponders in the b-wk1 and b-wk4 groups, respectively. Once the decline in viral load was known, genotype, age, sex and baseline viral load did not provide additional power in predicting treatment responses. CONCLUSION: A fall of 1.05 log10 in HCV RNA at week 4 predicts those patients who will not respond, identifying one-half of all nonresponders; this allows therapy to be stopped early, without depriving any patient who would have an SVR from treatment.

Adult↗
PubMed2002

Clinical impact of human herpesvirus 6 infection after liver transplantation.

BACKGROUND: Reactivation of human herpesvirus 6 (HHV-6) appears to be common after transplant. Viral reactivation may result in febrile illness and may also play an immunomodulatory role that leads to indirect effects such as opportunistic infections and rejection. The objective of this study was to determine the clinical impact of HHV-6 infection after liver transplantation including both direct and indirect effects. METHODS: This was a prospective single center cohort study of 200 consecutive patients undergoing liver transplantation. Systemic serial HHV-6 viral load measurements and all clinical outcomes including development of opportunistic infections, cytomegalovirus (CMV) disease, and rejection were determined. RESULTS: HHV-6 infection (defined as viral load > or = 2 log10 copies/microg input DNA) occurred in 56/200 (28%) patients. Symptomatic disease attributable to HHV-6 alone occurred in 2/200 (1%) patients. Univariate analysis revealed HHV-6 infection was associated with the development of opportunistic infection and CMV disease. In a multivariate analysis designed to control for the level of immunosuppression, the risk of opportunistic infection increased by 3.68-fold in patients with HHV-6 infection (95% confidence interval [CI], 1.86-7.27; P=0.001). In a similar multivariate analysis, the risk of CMV disease increased by 3.59-fold in patients with HHV-6 infection (95% CI, 1.53-8.44; P=0.003). HHV-6 infection was not associated with rejection except in the subgroup of patients with rejection after 30 days posttransplant (odds ration 2.27; 95% CI, 1.09-4.77; P=0.029). CONCLUSIONS: HHV-6 reactivation after transplant is common and is associated with the development of opportunistic infections and CMV disease and possibly with a subgroup of acute rejection episodes. HHV-6 infection likely has a significant impact in transplant recipients through indirect effects of viral replication.

Adult↗
PubMed2002

Effects of 810 nm laser irradiation on in vitro growth of bacteria: comparison of continuous wave and frequency modulated light.

BACKGROUND AND OBJECTIVES: Low intensity laser therapy may modify growth of wound bacteria, which could affect wound healing. This study compares the effects on bacteria of 810 nm laser using various delivery modes (continuous wave or frequency modulated light at 26, 292, 1000, or 3800 Hz). STUDY DESIGN/MATERIALS AND METHODS: Staphylococcus (S.) aureus, Escherichia (E.) coli, and Pseudomonas (P.) aeruginosa were plated on agar and then irradiated (0.015 W/cm(2); 1-50 J/cm(2)) or used as controls (sham irradiated); growth was examined after 20 hours of incubation post exposure. RESULTS: There were interactions of species and modulation frequency in the overall effects of irradiation (P = 0.0001), and in the radiant exposure mediated effects (P = 0.0001); thus individual frequencies and each bacterium were analysed separately. Bacteria increased following 3800 Hz (P = 0.0001) and 1000 Hz (P = 0.0001) pulsed irradiation; at particular radiant exposures P. aeruginosa proliferated significantly more than other bacteria. Pulsed laser at 292 and 26 Hz also produced species-dependent effects (P = 0.0001; P = 0.0005); however, the effects for different radiant exposures were not significant. Bacterial growth increased overall, independent of species, using continuous mode laser, significantly so at 1 J/cm(2) (P = 0.02). Analysis of individual species demonstrated that laser-mediated growth of S. aureus and E. coli was dependent on pulse frequency; for S. aureus, however, there was no effect for different radiant exposures. Further tests to examine the radiant exposure effects on E. coli showed that growth increased at a frequency of 1000 Hz (2 J/cm(2); P = 0.03). P. aeruginosa growth increased up to 192% using pulsed irradiation at 1000-3800 Hz; whereas 26-292 Hz laser produced only a growth trend. CONCLUSIONS: The findings of this study point to the need for wound cultures prior to laser irradiation of infected wounds. Similar investigations using other common therapeutic wavelengths are recommended.

Dose-Response Relationship, Radiation↗
PubMed2002

Cytomegalovirus glycoprotein B genotype does not correlate with outcomes in liver transplant patients.

BACKGROUND: Based on sequence variation in the UL55 gene that encodes glycoprotein B (gB), human cytomegalovirus (CMV) can be classified into four gB genotypes. Previous studies have suggested there could be an association between CMV gB genotype and clinical outcome in transplant patients. OBJECTIVES: The goal of this study was to determine the distribution of gB genotypes in a cohort of liver transplant recipients with CMV infection and the effect of gB type on clinical outcomes including CMV disease and rejection. STUDY DESIGN: DNA was extracted directly from the blood of 58 liver transplant recipients with CMV infection. The gB genotype of CMV was determined using the polymerase chain reaction to amplify a region of UL55, followed by restriction analysis based on HinfI and RsaI digestion. Results were correlated with CMV viral load, symptomatic disease, and development of acute rejection. RESULTS: The distribution of CMV gB genotypes was: gB1, 15/58 (25.9%); gB2, 16/58 (27.6%); gB3, 21/58 (36.2%); gB4, 2/58 (3.4%) and four patients (6.9%) had mixed infection. No correlation between CMV genotype and peak CMV viral load was observed. Symptomatic CMV disease developed in 25/58 (43.1%) patients and 26/58 (44.8%) had acute rejection. The rate of CMV disease and acute graft rejection in patients infected with the different CMV gB genotypes was not significantly different. However, all four patients with infection with a mixture of CMV gB genotypes developed progression to CMV disease (P=0.030). CONCLUSIONS: The gB genotype did not correlate with peak CMV viral load and with the development of CMV disease or acute rejection following liver transplantation.

Acute Disease↗
PubMed2002

The production of transgenic pigs for potential use in clinical xenotransplantation: microbiological evaluation.

Debate over the infection hazards of pig-to-human xenotransplantation has focused mainly on the porcine endogenous retroviruses (PERV). However, hazards of exogenous infectious agents possibly associated with the xenograft have also been evaluated (Xenotransplantation 2000; 7: 143). We report the results of a health monitoring program demonstrating the exclusion of more than 80 potential pathogens from nine cohorts of pigs reared in a high welfare bioexclusion facility as potential xenograft source animals. A dynamic bacterial flora of pigs reared under barrier conditions was characterized, emphasizing the significance of monitoring for multiresistant antimicrobial sensitivity patterns. Evidence was found for exclusion of two commonly residual exogenous viruses, porcine cytomegalovirus and porcine lymphotropic herpesviruses, among a proportion of the cohorts tested. Finally, there was histopathological evidence for low grade pneumonitis among sentinel pigs, likely to have been associated with the use of quaternary ammonium disinfectants during the production process, indicating a need for review of toxicology data for disinfectant agents used in such bioexclusion systems. Intensive health monitoring programs, based upon regularly updated recommendations from the microbiological research community, will enable significant reductions in the potential hazards associated with pig-to-human xenotransplantation.

Animal Husbandry↗
PubMed2002

The production of transgenic pigs for potential use in clinical xenotransplantation: baseline clinical pathology and organ size studies.

This report describes the results of hematology, serum biochemistry, growth, and organ weight studies undertaken on pigs from nine cohorts of qualified pathogen free (QPF) pigs reared within a high welfare bioexclusion facility as potential organ source animals. Confirmation of the high health status of the pigs was given through total leukocyte counts and serum globulin concentrations that fell below the expected reference range for conventional pigs. The calculated mean growth rate for QPF pigs was found to exceed target rates set for optimum genotype commercial pig herds. Body weights of QPF pigs were compared with kidney, heart and liver weights at necropsy.

Animals↗
PubMed2002

Interactions between cytomegalovirus, human herpesvirus-6, and the recurrence of hepatitis C after liver transplantation.

Recurrence of hepatitis C (HCV) following liver transplantation is common. Herpesvirus reactivation following transplant may have an immunomodulatory effect resulting in increased HCV replication. We studied whether cytomegalovirus (CMV) and human herpesvirus-6 (HHV-6) may be associated with HCV recurrence and viral load after transplant. We prospectively followed 66 HCV liver-transplant recipients with serial viral load testing for CMV and HHV-6. Infection and viral load were correlated with the development of biopsy-proven HCV recurrence and HCV viral loads. Histologic recurrence of HCV occurred in 41/66 (62.1%) patients. In the primary analysis, CMV infection and disease, and HHV-6 infection were not associated with HCV recurrence. Peak CMV and HHV-6 viral loads were not significantly different in patients with and without recurrence. No correlation was observed between HCV viral loads at 1 and 3 months post-transplant and peak HHV-6 or CMV viral loads. In a subgroup analysis, HHV-6 infection was associated with the development of more severe recurrence (hepatitis and/or fibrosis score > or = 2) (p = 0.01). Also, fibrosis scores at last follow up were higher in patients with CMV disease (1.67 vs. 0.56; p = 0.016) and in patients with HHV-6 infection (1.18 vs. 0.55; p = 0.031). In conclusion, HHV-6 and CMV infection and viral load were not associated with increased overall rates of HCV recurrence or HCV viral load after liver transplantation but may be associated with more severe forms of recurrence.

Cytomegalovirus↗
PubMed2002

Effects of 630-, 660-, 810-, and 905-nm laser irradiation delivering radiant exposure of 1-50 J/cm2 on three species of bacteria in vitro.

OBJECTIVE: To examine the effects of low-intensity laser therapy (LILT) on bacterial growth in vitro. BACKGROUND DATA: LILT is undergoing investigation as a treatment for accelerating healing of open wounds. The potential of coincident effects on wound bacteria has received little attention. Increased bacterial proliferation could further delay recovery; conversely inhibition could be beneficial. MATERIALS AND METHODS: Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus were plated on agar and then irradiated with wavelengths of 630, 660, 810, and 905 nm (0.015 W/cm(2)) and radiant exposures of 1-50 J/cm(2). In addition, E. coli was irradiated with 810 nm at an irradiance of 0.03 W/cm(2) (1-50 J/cm(2)). Cells were counted after 20 h of incubation post LILT. Repeated measures ANOVA and Tukey adjusted post hoc tests were used for analysis. RESULTS: There were interactions between wavelength and species (p = 0.0001) and between wavelength and radiant exposure (p = 0.007) in the overall effects on bacterial growth; therefore, individual wavelengths were analyzed. Over all types of bacteria, there were overall growth effects using 810- and 630-nm lasers, with species differences at 630 nm. Effects occurred at low radiant exposures (1-20 J/cm(2)). Overall effects were marginal using 660 nm and negative at 905 nm. Inhibition of P. aeruginosa followed irradiation using 810 nm at 5 J/cm(2) (-23%; p = 0.02). Irradiation using 630 nm at 1 J/cm(2) inhibited P. aeruginosa and E. coli (-27%). Irradiation using 810 nm (0.015 W/cm(2)) increased E. coli growth, but with increased irradiance (0.03 W/cm(2)) the growth was significant (p = 0.04), reaching 30% at 20 J/cm(2) (p = 0.01). S. aureus growth increased 27% following 905-nm irradiation at 50 J/cm(2). CONCLUSION: LILT applied to wounds, delivering commonly used wavelengths and radiant exposures in the range of 1-20 J/cm(2), could produce changes in bacterial growth of considerable importance for wound healing. A wavelength of 630 nm appeared to be most commonly associated with bacterial inhibition. The findings of this study might be useful as a basis for selecting LILT for infected wounds.

Escherichia coli↗