Female sex and ipsilateral reoperation risk following mesh-based inguinal hernia repair: a cohort study including 131,626 repairs in adults from an integrated healthcare system over a 10-year period.

PURPOSE: We sought to compare females and males for the risk of reoperation following different inguinal hernia repair approaches (open, laparoscopic, and robotic). METHODS: We conducted a retrospective cohort study including all patients aged ≥ 18 who underwent first inguinal hernia repair with mesh within a US integrated healthcare system (2010-2020). Data were obtained from the system's integrated electronic health record. Multiple Cox proportional-hazards regression was used to evaluate the association between sex and risk for ipsilateral reoperation during follow-up. Analysis was stratified by surgical approach (open, laparoscopic, and robotic). RESULTS: The study cohort was comprised of 110,805 patients who underwent 131,626 inguinal hernia repairs with mesh, 10,079 (7.7%) repairs were in females. After adjustment for confounders, females had a higher risk of reoperation than males following open groin hernia repair (hazard ratio [HR] = 1.98, 95% CI 1.74-2.25), but a lower reoperation risk following laparoscopic repair (HR = 0.70, 95% CI 0.51-0.97). The crude 5-year cumulative reoperation probability following robotic repair was 2.8% in males and no reoperations were observed for females. Of females who had a reoperation, 10.3% (39/378) were for a femoral hernia, while only 0.6% (18/3110) were for femoral hernias in males. CONCLUSION: In a large multi-center cohort of mesh-based inguinal hernia repair patients, we found a higher risk for reoperation in females after an open repair approach compared to males. Lower risk was observed for females through a minimally invasive approach (laparoscopic or robotic) and may be due to the ability to identify an occult femoral hernia through these approaches.

Risk factors for reoperation following inguinal hernia repair: results from a cohort of patients from an integrated healthcare system.

PURPOSE: Inguinal hernia repair is one of the most common operations performed globally. Identification of risk factors that contribute to hernia recurrence following an index inguinal hernia repair, especially those that are modifiable, is of paramount importance. Therefore, we sought to investigate risk factors for reoperation following index inguinal hernia repair. METHODS: 125,133 patients aged ≥ 18 years who underwent their first inguinal hernia repair with mesh within a large US integrated healthcare system were identified for a cohort study (2010-2020). Laparoscopic, robotic, and open procedures were included. The system's integrated electronic health record was used to obtain data on demographics, patient characteristics, surgical characteristics, and reoperations. The association of these characteristics with ipsilateral reoperation during follow-up was modeled using Cox proportional-hazards regression. Risk factors were selected into the final model by stepwise regression with Akaike Information Criteria, which quantifies the amount of information lost if a factor is left out of the model. Factors associated with reoperation with p < 0.05 were considered statistically significant. RESULTS: The cumulative incidence of reoperation at 5-year follow-up was 2.4% (95% CI 2.3-2.5). Increasing age, female gender, increasing body mass index, White race, chronic pulmonary disease, diabetes, drug abuse, peripheral vascular disease, and bilateral procedures all associated with a higher risk for reoperation during follow-up. CONCLUSION: This study identifies several risk factors associated with reoperation following inguinal hernia repair. These risk factors may serve as targets for optimization protocols prior to elective inguinal hernia repair, with the goal of reducing reoperation risk.

Mesh-based inguinal hernia repairs in an integrated healthcare system and surgeon and hospital volume: a cohort study of 110,808 patients from over a decade.

PURPOSE: The aim of this study was to describe a cohort of patients who underwent inguinal hernia repair within a United States-based integrated healthcare system (IHS) and evaluate the risk for postoperative events by surgeon and hospital volume within each surgical approach, open, laparoscopic, and robotic. METHODS: Patients aged ≥ 18 years who underwent their first inguinal hernia repair were identified for a cohort study (2010-2020). Average annual surgeon and hospital volume were broken into quartiles with the lowest volume quartile as the reference group. Multiple Cox regression evaluated risk for ipsilateral reoperation following repair by volume. All analyses were stratified by surgical approach (open, laparoscopic, and robotic). RESULTS: 110,808 patients underwent 131,629 inguinal hernia repairs during the study years; procedures were performed by 897 surgeons at 36 hospitals. Most repairs were open (65.4%), followed by laparoscopic (33.5%) and robotic (1.1%). Reoperation rates at 5 and 10 years of follow-up were 2.4% and 3.4%, respectively; rates were similar across surgical groups. In adjusted analysis, surgeons with higher laparoscopic volumes had a lower reoperation risk (27-46 average annual repairs: hazard ratio [HR] = 0.63, 95% confidence interval [CI] 0.53-0.74; ≥ 47 repairs: HR 0.53, 95% CI 0.44-0.64) compared to those in the lowest volume quartile (< 14 average annual repairs). No differences in reoperation rates were observed in reference to surgeon or hospital volume following open or robotic inguinal hernia repair. CONCLUSION: High-volume surgeons may reduce reoperation risk following laparoscopic inguinal hernia repair. We hope to better identify additional risk factors for inguinal hernia repair complications and improve patient outcomes with future studies.

Noninvasive tracking of gene transcript and neuroprotection after gene therapy.

Gene therapy holds exceptional potential for translational medicine by improving the products of defective genes in diseases and/or providing necessary biologics from endogenous sources during recovery processes. However, validating methods for the delivery, distribution and expression of the exogenous genes from such therapy can generally not be applicable to monitor effects over the long term because they are invasive. We report here that human granulocyte colony-stimulating factor (hG-CSF) complimentary DNA (cDNA) encoded in self-complementary adeno-associated virus-type 2 adeno-associated virus, as delivered through eye drops at multiple time points after cerebral ischemia using bilateral carotid occlusion for 60 min (BCAO-60) led to significant reduction in mortality rates, cerebral atrophy and neurological deficits in C57black6 mice. Most importantly, we validated hG-CSF cDNA expression using translatable magnetic resonance imaging (MRI) in living brains. This noninvasive approach for monitoring exogenous gene expression in the brains has potential for great impact in the area of experimental gene therapy in animal models of heart attack, stroke, Alzheimer's dementia, Parkinson's disorder and amyotrophic lateral sclerosis, and the translation of such techniques to emergency medicine.

Comparison between single and combined post-treatment with S-Methyl-N,N-diethylthiolcarbamate sulfoxide and taurine following transient focal cerebral ischemia in rat brain.

We have recently reported on the efficacy of an N-methyl-d-aspartate (NMDA) receptor partial antagonist, S-Methyl-N,N-diethylthiolcarbamate sulfoxide (DETC-MeSO), in improving outcome following stroke, including reduced infarct size and calcium influx, suppressing the endoplasmic reticulum (ER) stress-induced apoptosis as well as improving behavioral outcome. DETC-MeSO was shown to suppress the protein kinase R-like endoplasmic reticulum kinase (PERK) pathway, one of the major ER stress pathways. Several studies including ours have provided evidence that taurine also has neuroprotective effects through reducing apoptosis and inhibiting activating transcription factor 6 (ATF6) and inositol requiring enzyme 1 (IRE-1) pathways. We hypothesized that a combined treatment with DETC-MeSO and taurine would ameliorate ischemia-induced brain injury by inhibiting all three ER stress pathways. Twenty four hours following reperfusion of a 2-h ischemic stroke, rats received either 0.56-mg/kg DETC-MeSO or 40-mg/kg of taurine, either alone or in combination, subcutaneously for 4days. Our study showed that combined DETC-MeSO and taurine, but not DETC-MeSO alone at the dose used, greatly reduced the infarct size, improved performance on the neuro-score test and attenuated proteolysis of αII-spectrin. Meanwhile, the level of the pro-apoptotic protein, Bax, declined and the anti-apoptotic protein, B-cell lymphoma 2 (BCL-2), expression was markedly increased. Combination therapy decreased both caspase-12 and caspase-3 activation by preventing the release of Cytochrome-c from mitochondria, indicating attenuation of apoptosis in ischemic infarct. Glucose-regulated protein (GRP)78 as a marker of the unfolded protein response decreased and levels of the key ER stress protein markers p-PERK-ATF4, p-eIF2α and cleaved-ATF-6 were found to significantly decline. NeuN expression levels indicated that more neurons were protected in the presence of DETC-MeSO and taurine. We also showed that combined treatment can prevent gliosis and increase p-AKT a pro-survival marker in the penumbra. Therefore, we conclude that combined treatment with both DETC-MeSO and taurine synergistically inhibits all three ER stress pathways and apoptosis and therefore can be a novel and effective treatment after ischemic stroke.

HLA class II diversity in HIV-1 uninfected individuals from the placebo arm of the RV144 Thai vaccine efficacy trial.

The RV144 HIV vaccine trial in Thailand elicited antibody responses to the envelope of HIV-1, which correlated significantly with the risk of HIV-1 acquisition. Human leukocyte antigen (HLA) class II molecules are essential in antigen presentation to CD4 T cells for activation of B cells to produce antibodies. We genotyped the classical HLA-DRB1, DQB1, and DPB1 genes in 450 individuals from the placebo arm of the RV144 study to determine the background allele and haplotype frequencies of these genes in this cohort. High-resolution 4 and 6-digit class II HLA typing data was generated using sequencing-based methods. The observed diversity for the HLA loci was 33 HLA-DRB1, 15 HLA-DQB1, and 26 HLA-DPB1 alleles. Common alleles with frequencies greater than 10% were DRB1*07:01, DRB1*09:01, DRB1*12:02, DRB1*15:02, DQB1*02:01/02, DQB1*03:01, DQB1*03:03, DQB1*05:01, DQB1*05:02, DPB1*04:01:01, DPB1*05:01:01, and DPB1*13:01:01. We identified 28 rare alleles with frequencies of less than 1% in the Thai individuals. Ambiguity for HLA-DPB1*28:01 in exon 2 was resolved to DPB1*296:01 by next-generation sequencing of all exons. Multi-locus haplotypes including HLA class I and II loci were reported in this study. This is the first comprehensive report of allele and haplotype frequencies of all three HLA class II genes from a Thai population. A high-resolution genotyping method such as next-generation sequencing avoids missing rare alleles and resolves ambiguous calls. The HLA class II genotyping data generated in this study will be beneficial not only for future disease association/vaccine efficacy studies related to the RV144 study, but also for similar studies in other diseases in the Thai population, as well as population genetics and transplantation studies.

Immunogenetic influences on acquisition of HIV-1 infection: consensus findings from two African cohorts point to an enhancer element in IL19 (1q32.2).

Numerous reports have suggested that immunogenetic factors may influence human immunodeficiency virus (HIV)-1 acquisition, yet replicated findings that translate between study cohorts remain elusive. Our work aimed to test several hypotheses about genetic variants within the IL10-IL24 gene cluster that encodes interleukin (IL)-10, IL-19, IL-20 and IL-24. In aggregated data from 515 Rwandans and 762 Zambians with up to 12 years of follow-up, 190 single-nucleotide polymorphisms passed quality control procedures. When HIV-1-exposed seronegative subjects (n=486) were compared with newly seroconverted individuals (n=313) and seroprevalent subjects (n=478) who were already infected at enrollment, rs12407485 (G>A) in IL19 showed a robust association signal in adjusted logistic regression models (odds ratio=0.64, P=1.7 × 10(-4) and q=0.033). Sensitivity analyses demonstrated that (i) results from both cohorts and subgroups within each cohort were highly consistent; (ii) verification of HIV-1 infection status after enrollment was critical; and (iii) supporting evidence was readily obtained from Cox proportional hazards models. Data from public databases indicate that rs12407485 is part of an enhancer element for three transcription factors. Overall, these findings suggest that molecular features at the IL19 locus may modestly alter the establishment of HIV-1 infection.

Host genetics and immune control of HIV-1 infection: fine mapping for the extended human MHC region in an African cohort.

Multiple major histocompatibility complex (MHC) loci encoding human leukocyte antigens (HLA) have allelic variants unequivocally associated with differential immune control of HIV-1 infection. Fine mapping based on single nucleotide polymorphisms (SNPs) in the extended MHC (xMHC) region is expected to reveal causal or novel factors and to justify a search for functional mechanisms. We have tested the utility of a custom fine-mapping platform (the ImmunoChip) for 172 HIV-1 seroconverters (SCs) and 449 seroprevalent individuals (SPs) from Lusaka, Zambia, with a focus on more than 6400 informative xMHC SNPs. When conditioned on HLA and nongenetic factors previously associated with HIV-1 viral load (VL) in the study cohort, penalized approaches (HyperLasso models) identified an intergenic SNP (rs3094626 between RPP21 and HLA-E) and an intronic SNP (rs3134931 in NOTCH4) as novel correlates of early set-point VL in SCs. The minor allele of rs2857114 (downstream from HLA-DOB) was an unfavorable factor in SPs. Joint models based on demographic features, HLA alleles and the newly identified SNP variants could explain 29% and 15% of VL variance in SCs and SPs, respectively. These findings and bioinformatics strongly suggest that both classic and nonclassic MHC genes deserve further investigation, especially in Africans with relatively short haplotype blocks.

Modified vaccinia virus Ankara-based vaccine vectors induce apoptosis in dendritic cells draining from the skin via both the extrinsic and intrinsic caspase pathways, preventing efficient antigen presentation.

Dendritic cells (DC) are potent antigen-presenting cells and central to the induction of immune responses following infection or vaccination. The collection of DC migrating from peripheral tissues by cannulation of the afferent lymphatic vessels provides DC which can be used directly ex vivo without extensive in vitro manipulations. We have previously used bovine migrating DC to show that recombinant human adenovirus 5 vectors efficiently transduce afferent lymph migrating DEC-205(+) CD11c(+) CD8(-) DC (ALDC). We have also shown that recombinant modified vaccinia virus Ankara (MVA) infects ALDC in vitro, causing downregulation of costimulatory molecules, apoptosis, and cell death. We now show that in the bovine system, modified vaccinia virus Ankara-induced apoptosis in DC draining from the skin occurs soon after virus binding via the caspase 8 pathway and is not associated with viral gene expression. We also show that after virus entry, the caspase 9 pathway cascade is initiated. The magnitude of T cell responses to mycobacterial antigen 85A (Ag85A) expressed by recombinant MVA-infected ALDC is increased by blocking caspase-induced apoptosis. Apoptotic bodies generated by recombinant MVA (rMVA)-Ag85A-infected ALDC and containing Ag85A were phagocytosed by noninfected migrating ALDC expressing SIRPα via actin-dependent phagocytosis, and these ALDC in turn presented antigen. However, the addition of fresh ALDC to MVA-infected cultures did not improve on the magnitude of the T cell responses; in contrast, these noninfected DC showed downregulation of major histocompatibility complex class II (MHC-II), CD40, CD80, and CD86. We also observed that MVA-infected ALDC promoted migration of DEC-205(+) SIRPα(+) CD21(+) DC as well as CD4(+) and CD8(+) T cells independently of caspase activation. These in vitro studies show that induction of apoptosis in DC by MVA vectors is detrimental to the subsequent induction of T cell responses.

Migratory sub-populations of afferent lymphatic dendritic cells differ in their interactions with Mycobacterium bovis Bacille Calmette Guerin.

Understanding how pathogens or vaccine antigens are targeted to dendritic cell (DC) subsets is important for disease pathogenesis studies and vaccine design. We characterised the sub-populations of migrating bovine DC with functional and phenotypic diversity present in pseudoafferent lymph draining the skin. These skin draining DC exist as a series of maturation dependent subsets with differential capacities for antigen uptake and cytokine expression, and include both Langerhans' cells (LC) and dermal derived cells. Furthermore, Mycobacterium bovis Bacille Calmette Guerin, a vaccine which is administered by the intradermal route, was only taken up by a small number of the migrating DC, which were SIRPα(+) and expressed the mannose receptor and CD1b. This was evident following in vitro infection and also in vivo following inoculation of green fluorescent BCG over the lymphatic cannulation site. Only the SIRPα(+) DC were able to present antigen to T cells isolated from BCG vaccinated calves. Furthermore, presentation of BCG antigens by DC to T lymphocytes was ineffective compared to mycobacterial proteins. However, mycobacterial antigen 85 was delivered more effectively to DC via an adenoviral vector and the magnitude of the subsequent antigen-specific T cell response was significantly increased. This study further extends our understanding of the biology of migrating DC, identifies potential explanations for the modest success of BCG vaccination and demonstrates that targeted delivery of antigens via adenoviruses to DC can improve antigen presentation.

Differential effects of viral vectors on migratory afferent lymph dendritic cells in vitro predict enhanced immunogenicity in vivo.

Targeting dendritic cells (DC) is key to driving effective immune responses. Lymphatic cannulation provides access to the heterogeneous populations of DC draining peripheral sites in rodents and ruminants. Afferent lymph DEC-205(+) CD11c(+) SIRPα(+) DC were preferentially infected ex vivo with three vaccine viral vectors: recombinant human replication-defective human adenovirus 5 (rhuAdV5), recombinant modified vaccinia virus Ankara (rMVA), and recombinant fowlpox virus (rFPV), all expressing green fluorescent protein (GFP). The rhuAdV5-infected cells remained viable, and peak GFP expression was observed 16 to 24 h posttransduction. Increasing the incubation period of DC with rhuAdV5 enhanced GFP expression. In contrast, DC infected with rMVA-GFP or rFPV-GFP became rapidly apoptotic and GFP expression peaked at 6 h postinfection. Delivery of foot-and-mouth disease virus (FMDV) A(22) antigen to DC by rhuAdV5-FMDV-A(22) ex vivo resulted in significantly greater CD4(+) T cell proliferation than did delivery by rFPV-FMDV-A(22). Delivery of rhuAdV5-GFP in oil adjuvant in vivo, to enhance DC-vector contact, resulted in increased GFP expression in migrating DC compared to that with vector alone. Similarly, CD4(+) T cell responses were significantly enhanced when using rhuAdV5-FMDV-A(22) in adjuvant. Therefore, the interaction between viral vectors and afferent lymph DC ex vivo can predict the outcome of in vivo immunization and provide a means of rapidly assessing the effects of vector modification.

Epigenetic modulation of MAGE-A3 antigen expression in multiple myeloma following treatment with the demethylation agent 5-azacitidine and the histone deacetlyase inhibitor MGCD0103.

BACKGROUND AIMS: Immunotherapy targeting MAGE-A3 in multiple myeloma (MM) could eradicate highly aggressive and proliferative clonal cell populations responsible for relapse. However, expression of many cancer-testis antigens, including MAGE-A3, can be heterogeneous, leading to the potential for tumor escape despite MAGE-A3-induced immunity. We hypothesized that a combination of the hypomethylating agent 5-azacitidine (5AC) and the histone deacetylase inhibitor (HDACi) MGCD0103 (MGC) could induce MAGE-A3 expression in MAGE-A3-negative MM, resulting in recognition and killing of MM cells by MAGE-A3-specific cytotoxic T lymphocytes (CTL). METHODS: Gene expression analyses of MAGE-A3 expression in primary MM patient samples at diagnosis and relapse were completed to identify populations that would benefit from MAGE-A3 immunotherapy. MM cell lines were treated with 5AC and MGC. Real-time polymerase chain reaction (PCR) and Western blotting were performed to assess MAGE-A3 RNA and protein levels, respectively. Chromium-release assays and interferon (IFN) secretion assays were employed to ascertain MAGE-A3 CTL specificity against treated targets. RESULTS: Gene expression analysis revealed that MAGE-A3 is expressed in MM patients at diagnosis (25%) and at relapse (49%). We observed de novo expression of MAGE-A3 RNA and protein in MAGE-A3-negative cell lines treated with 5AC. MGC treatment alone did not induce expression but sequential 5AC/MGC treatment led to enhanced expression and augmented recognition by MAGE-A3-specific CTL, as assessed by (51)Cr-release assays (P = 0.047) and enzyme-linked immunosorbent assay (ELISA) for IFN-γ secretion (P = 0.004). CONCLUSIONS: MAGE-A3 is an attractive target for immunotherapy of MM and epigenetic modulation by 5AC, and MGC can induce MAGE-A3 expression and facilitate killing by MAGE-A3-specific CTL.

A structured course teaching junior doctors invasive medical procedures results in sustained improvements in self-reported confidence.

Pressure on working hours has led to a decrease in opportunities for training in invasive medical procedures for junior doctors. The effect of a structured course on immediate and medium-term changes in self-reported confidence was investigated. A one-day model-based practical course was run on two separate occasions teaching central venous line placement, lumbar puncture, Seldinger-technique chest drain insertion and knee joint aspiration. Attendees were asked to indicate their confidence in each procedure on a 10-point Likert scale before, immediately after and three months after the course. Significant improvements in self-reported confidence were seen for all procedures which were sustained at three months. Feedback was universally positive. Practical preclinical training may be a useful adjunct to patient-based training in invasive procedures. The course was particularly popular with foundation year trainees: ideally this training should be available before trainees' first exposure in the clinical setting.

The risk of early and late CMV DNAemia associated with Campath use in stem cell transplant recipients.

The risks associated with in vivo and ex vivo use of Campath-1H and -1G in a cohort of 206 stem cell transplant recipients for human CMV (HCMV) DNAemia have been quantified. DNAemia showed a biphasic incidence pattern with an inflexion at day 60. The first phase had a linear risk rate for HCMV DNAemia of 0.3% per day, whereas the second phase had a substantially lower risk rate of 0.058% per day. In multivariable analyses, risk factors for early DNAemia were HCMV serostatus, radiotherapy-based conditioning and CD34 stem cell dose, with the use of in vivo Campath-1H having the most significant risk (hazards ratio=3.68; 95% CI=2.02-6.72; P<0.001). Ex vivo use of Campath was not associated with an increased risk for HCMV DNAemia. Patients receiving either in vivo Campath-1H or -1G experienced HCMV DNAemia earlier (27 and 33 days, respectively) compared with patients receiving no Campath (time to DNAemia, 51 days; P=0.0006). Multivariable analysis of risk factors for HCMV DNAemia occurring beyond 100 days after transplant were older age, acute GVHD>grade II and a lower CD34 stem cell dose, whereas Campath-1H use was not associated with late HCMV DNAemia.

Paternal effects on seed germination: a barrier to the genetic assimilation of an endemic plant taxon?

We used a crossing experiment to investigate post-zygotic barriers that might limit introgression between a pair of closely-related, gynodioecious plant species--the widespread weed Silene vulgaris and the local Swedish endemic S. uniflora ssp. petraea. The study not only considered the effects of hybridization on conventionally-used (primary) fitness components such as seed set and progeny survival, but also provided a test for the effects of interspecific hybridization on characters with more subtle or habitat-specific effects on fitness. We detected highly significant paternal effects on seed germination properties, with the germination characteristics of hybrid seed resembling those of the species that served as the pollen donor. These paternal effects on germination represent a potentially strong barrier to interspecific introgression in the two species' natural habitats, where an inappropriate germination response in the habitat of the maternal parent may lead to the failure of seedling establishment. Interspecific crosses had weak or variable effects on progeny survival, flowering and sex ratio, but these effects could not be interpreted in terms of barriers to introgression. Our results indicate that nuclear restorers in S. vulgaris have the capacity to suppress cytoplasmic male-sterility genes in its endemic congener.

MsrA protects cardiac myocytes against hypoxia/reoxygenation induced cell death.

Reactive oxygen species (ROS) are critical in tissue responses to ischemia-reperfusion. The enzyme methionine sulfoxide reductase-A (MsrA) is capable of protecting cells against oxidative damage by reversing damage to proteins caused by methionine oxidation or by decreasing ROS through a scavenger mechanism. The current study employed adenovirus mediated over-expression of MsrA in primary neonatal rat cardiac myocytes to determine the effect of this enzyme in protecting against hypoxia/reoxygenation in this tissue. Cells were transduced with MsrA encoding adenovirus and subjected to hypoxia/reoxygenation. Apoptotic cell death was decreased by greater than 45% in cells over-expressing MsrA relative to cells transduced with a control virus. Likewise total cell death as determined by levels of LDH release was dramatically decreased by MsrA over-expression. These observations indicate that MsrA is protective against hypoxia/reoxygenation stress in cardiac myocytes and point to MsrA as an important therapeutic target for ischemic heart disease.

Influence of the nature of the antigen on the boosting of responses to mycobacteria in M. bovis-BCG vaccinated cattle.

Mycobacterium bovis is the causative agent of bovine tuberculosis (TB) and of a proportion of human TB. Protection against TB requires Th1 responses and worsening of disease is associated with Th2 responses. To help clarify the nature of the response to mycobacteria, the responses from M. bovis-BCG vaccinated cattle boosted with live mycobacteria (BCG), bacterial soluble antigens (PPD) or PBS were evaluated. The results indicated that macrophages may be the major cell population ingesting and presenting mycobacteria in BCG boosted animals, while B-cells seem able to ingest and present PPD to T-cells in PPD boosted animals.

Modelling cytomegalovirus replication patterns in the human host: factors important for pathogenesis.

Human cytomegalovirus can cause a diverse range of diseases in different immunocompromised hosts. The pathogenic mechanisms underlying these diseases have not been fully elucidated, though the maximal viral load during infection is strongly correlated with the disease. However, concentrating on single viral load measures during infection ignores valuable information contained during the entire replication history up to the onset of disease. We use a statistical model that allows all viral load data sampled during infection to be analysed, and have applied it to four immunocompromised groups exhibiting five distinct cytomegalovirus-related diseases. The results show that for all diseases, peaks in viral load contribute less to disease progression than phases of low virus load with equal amount of viral turnover. The model accurately predicted the time of disease onset for fever, gastrointestinal disease and pneumonitis but not for hepatitis and retinitis, implying that other factors may be involved in the pathology of these diseases.

A study to determine the safety profile and maximum tolerated dose of micafungin (FK463) in patients undergoing haematopoietic stem cell transplantation.

This open-label, dose-escalation study assessed the maximum tolerated dose (MTD) of the new antifungal micafungin in patients undergoing haematopoietic stem cell transplantation (HSCT). Participants received 3, 4, 6 or 8 mg/kg/day micafungin intravenously from 7 days to a maximum of 28 days or until neutropaenia resolved. The MTD was defined as the highest dose not causing the same Grade 3 or 4 adverse event in three or more patients. All 36 participants received >/=8 days treatment for a median of 18 days (range: 8-28); 1 patient withdrew consent and a further 11 discontinued to receive another systemic antifungal agent for a suspected infection. No case of confirmed invasive fungal infection occurred. Adverse events were those expected for patients undergoing HSCT and showed no evidence of dose-related toxicity. Criteria for MTD were not met; no patient had a Grade 3 or 4 adverse event considered causally related to micafungin. Thus, the MTD of micafungin can be inferred to be 8 mg/kg/day or higher.

Validation and clinical application of molecular methods for the identification of molds in tissue.

BACKGROUND: Invasive fungal infections due to less-common molds are an increasing problem, and accurate diagnosis is difficult. METHODS: We used our previously established molecular method, which allows species identification of molds in histological tissue sections, to test sequential specimens from 56 patients with invasive fungal infections who were treated at our institution from 1982 to 2000. RESULTS: The validity of the method was demonstrated with the establishment of a molecular diagnosis in 52 cases (93%). Confirmation of the causative organism was made in all cases in which a mold had been cultured from the tissue specimen. Less-common molds were identified in 7% of cases and appear to be an increasing problem. CONCLUSIONS: Our previously established method has proven to be of value in determining the incidence of invasive infection caused by less-common molds. Institutions should continue to pursue diagnosis of invasive fungal infections by means of tissue culture and microbiologic analysis.