What are the risk factors for postoperative infections of third molar extraction surgery: A retrospective clinical study?

BACKGROUND: This study aimed to identify (1) the predilection site of postoperative infection after third molar extraction surgery, (2) risk factors associated with postoperative infection, and (3) the cause of the difference between delayed- and early-onset infections. MATERIALS AND METHODS: This retrospective study included 1010 patients (396 male, 614 female) who had ≥1 third molars extracted (2407; 812 maxilla, 1595 mandible). The risk factors were classified as attributes, general health, anatomic, and operative. Outcome variables were delayed- and early-onset infections. RESULTS: Postoperative infection was completely absent in the maxilla, and all infections occurred in the mandible, with a probability of 1.94% (31/1595). Bivariate analysis for postoperative infection showed depth of inclusion and intraoperative hemostatic treatment to be significantly associated with the development of infections. Bivariate analysis for delayed- and early-onset infections showed simultaneous extraction of the left and right mandibular third molars to be prominent risk factors. CONCLUSIONS: Postoperative infection occurs mainly in the mandible, and that in the maxilla is very rare. The risk of postoperative infection in the mandible was found to be related to the depth of inclusion and intraoperative hemostatic treatment. Simultaneous extraction of the left and right mandibular third molars appear to increase the risk of delayed-onset postoperative infection.

Anti-TB drug concentrations and drug-associated toxicities among TB/HIV-coinfected patients.

Background: Toxicities due to anti-TB treatment frequently occur among TB/HIV-coinfected patients. Objectives: To determine the association between anti-TB drug concentrations and the occurrence of hepatotoxicity and peripheral neuropathy among TB/HIV-coinfected patients. Methods: TB/HIV-coinfected patients were started on standard dose anti-TB treatment according to WHO guidelines. Anti-TB drug concentrations were measured using HPLC 1, 2 and 4 h after drug intake at 2, 8 and 24 weeks following initiation of TB treatment. Participants were assessed for hepatotoxicity using Division of AIDS toxicity tables and for peripheral neuropathy using clinical assessment of tendon reflexes, vibration sensation or symptoms. Cox regression was used to determine the association between toxicities and drug concentrations. Results: Of the 268 patients enrolled, 58% were male with a median age of 34 years. Participants with no hepatotoxicity or mild, moderate and severe hepatotoxicity had a median C max of 6.57 (IQR 4.83-9.41) µg/mL, 7.39 (IQR 5.10-10.20) µg/mL, 7.00 (IQR 6.05-10.95) µg/mL and 3.86 (IQR 2.81-14.24) µg/mL, respectively. There was no difference in the median C max of rifampicin among those who had hepatotoxicity and those who did not ( P = 0.322). There was no difference in the isoniazid median C max among those who had peripheral neuropathy 2.34 (1.52-3.23) µg/mL and those who did not 2.21 (1.45-3.11) µg/mL ( P = 0.49). Conclusions: There was no association between rifampicin concentrations and hepatotoxicity or isoniazid concentrations and peripheral neuropathy among TB/HIV-coinfected patients.

High perceived social standing is associated with better health in HIV-infected Ugandan adults on highly active antiretroviral therapy.

Perceived social standing (PSS) was evaluated as a determinant of differences in health outcomes among Ugandan HIV-infected adults from Kampala using cross-sectional study design. PSS was defined using the MacArthur scale of subjective social status translated and adapted for the study setting. Socio-demographic and psychosocial correlates of PSS ranking at enrollment were determined using linear regression models. High versus low PSS was defined based on the median PSS score and evaluated as a determinant of body mass index, hemoglobin, quality of life (QOL) and frailty-related phenotype via linear regression. A log-binomial regression model estimated the relative-risk of good, very good or excellent versus fair or poor self-rated health (SRH) in relation to PSS. Older age, increasing social support and material wealth were correlated with high PSS ranking, whereas female sex, experience of multiple stigmas and multiple depressive symptoms were correlated with low PSS ranking. High PSS participants were on average 1.1 kg/m(2) heavier, had 4.7 % lower frailty scores and 3.6 % higher QOL scores compared to low PSS patients (all p < 0.05); they were also more likely to self-classify as high SRH (RR 1.4, 95 % confidence interval 1.1, 1.7) but had comparable hemoglobin levels (p = 0.634). Low PSS correlated with poor physical and psychosocial wellbeing in HIV-positive Ugandan adults. The assessment of PSS as part of clinical management, combined with efforts to reduce stigma and improve social support, may identify and possibly reduce PSS-associated health inequality in Ugandan adults with HIV.

Marked lateral deviation of the phrenic nerve due to variant origin and course of the thyrocervical trunk: a cadaveric study.

Phrenic nerve impairment can often lead to serious respiratory disorders under various pathological conditions. During routine dissection of an 88-year-old Japanese male cadaver, a victim of heart failure, we recognized an extremely rare variation of the right thyrocervical trunk arising from the subclavian artery laterally to the anterior scalene muscle. In addition to that, the ipsilateral phrenic nerve was drawn and displaced remarkably laterad by this vessel. We examined all of the branches arising from subclavian arteries, phrenic nerves and diaphragm muscles. The embryological background of this arterial variation is considered. The marked displacement with prolonged strain had a potential to cause phrenic nerve impairment with an atrophic change of the diaphragm muscle. Recently many image diagnostic technologies have been developed and are often used. However, it is still possible that rare variations like this case may be overlooked and can only be recognized by intimate regional examination while keeping these rare variations in mind.

Bloodstream infections in neonates with central venous catheters in three tertiary neonatal intensive care units in Pune, India.

BACKGROUND: Neonates admitted to the neonatal intensive care unit (NICU) are at risk for healthcare-associated infections, including central line-associated bloodstream infections. We aimed to characterize the epidemiology of bloodstream infections among neonates with central venous catheters admitted to three Indian NICUs. METHODS: We conducted a prospective cohort study in three tertiary NICUs, from May 1, 2017 until July 31, 2019. All neonates admitted to the NICU were enrolled and followed until discharge, transfer, or death. Cases were defined as positive blood cultures in neonates with a central venous catheter in place for greater than 2 days or within 2 days of catheter removal. RESULTS: During the study period, 140 bloodstream infections were identified in 131 neonates with a central venous catheter. The bloodstream infection rate was 11.9 per 1000 central line-days. Gram-negative organisms predominated, with 38.6% of cases caused by Klebsiella spp. and 14.9% by Acinetobacter spp. Antimicrobial resistance was prevalent among Gram-negative isolates, with 86.9% resistant to third- or fourth-generation cephalosporins, 63.1% to aminoglycosides, 61.9% to fluoroquinolones, and 42.0% to carbapenems. Mortality and length of stay were greater in neonates with bloodstream infection than in neonates without bloodstream infection (unadjusted analysis, p < 0.001). CONCLUSIONS: We report a high bloodstream infection rate among neonates with central venous catheters admitted to three tertiary care NICUs in India. Action to improve infection prevention and control practices in the NICU is needed to reduce the morbidity and mortality associated with BSI in this high-risk population.

Earlier initiation of antiretroviral therapy, increased tuberculosis case finding and reduced mortality in a setting of improved HIV care: a retrospective cohort study.

OBJECTIVES: High early mortality after antiretroviral therapy (ART) initiation in resource-limited settings is associated with low baseline CD4 cell counts and a high burden of opportunistic infections. Our large urban HIV clinic in Uganda has made concerted efforts to initiate ART at higher CD4 cell counts and to improve diagnosis and care of patients coinfected with tuberculosis (TB). We sought to determine associated treatment outcomes. METHODS: Routinely collected data for all patients who initiated ART from 2005 to 2009 were analysed. Median baseline CD4 cell counts by year of ART initiation were compared using the Cuzick test for trend. Mortality and TB incidence rates in the first year of ART were computed. Hazard ratios (HRs) were calculated using multivariable Cox proportional hazards models. RESULTS: First-line ART was initiated in 7659 patients; 64% were women, and the mean age was 37 years (standard deviation 9 years). Median baseline CD4 counts increased from 2005 to 2009 [82 cells/µL (interquartile range (IQR) 24, 153) to 148 cells/µL (IQR 61, 197), respectively; P<0.001]. The mortality rate fell from 6.5/100 person-years at risk (PYAR) [95% confidence interval (CI) 5.5-7.6 PYAR] to 3.6/100 PYAR (95% CI 2.2-5.8 PYAR). TB incidence rates increased from 8.2/100 PYAR (95% CI 7.1-9.5 PYAR) to 15.6/100 PYAR (95% CI 12.4-19.7 PYAR). A later year of ART initiation was independently associated with decreased mortality (HR 0.91; 95% CI 0.83-1.00; P=0.04). CONCLUSIONS: Baseline CD4 cell counts have increased over time and are associated with decreased mortality. Additional reductions in mortality might be a result of a better standard of care and increased TB case finding. Further efforts to initiate ART earlier should be prioritized even in a setting of capped or reduced funding for ART programmes.

Cognitive and affective impairments of a novel SCA/MND crossroad mutation Asidan.

BACKGROUND: A variety of hereditary spinocerebellar ataxia (SCA) develops a broad spectrum of both ataxia and non-ataxia symptoms. Cognitive and affective changes are one such non-ataxia symptoms, but have been described only in hereditary SCAs with exonic CAG gene expansion. METHODS: We newly found intronic hexanucleotide GGCCTG gene expansion in NOP56 gene as the causative mutation (=SCA36) in nine unrelated Japanese familial SCA originating from Asida river area in the western part of Japan, thus nicknamed Asidan for this mutation. These patients show unique clinical balance of cerebellar ataxia and motor neuron disease (MND), locating on the crossroad of these two diseases. In the nine families, 14 patients were clinically examined and genetically confirmed to Asidan. In the present study, we examined cognitive and affective analyses on 12 patients (seven men and five women) who agreed to join the examination with average age at onset of 53.1 ± 3.2 years, average duration of 12.1 ± 5.2 years, and current average age at 65.1 ± 6.2 years. RESULTS: The 12 Asidan patients demonstrated a significant decrease in their frontal executive functions measured by frontal assessment battery (FAB) and Montreal cognitive assessment (MoCA) compared with age- and gender-matched controls, whilst mini-mental state examination (MMSE) and Hasegawa dementia score-revised (HDS-R) were within normal range. The decline of frontal executive function was related to their disease duration and scale for the assessment and rating of ataxias (SARA). They also demonstrated mild depression and apathy. Single-photon emission tomography (SPECT) analysis showed that these Asidan patients showed decline of regional cerebral blood flow (rCBF) in a particular areas of cerebral cortices such as Brodmann areas 24 and 44-46. CONCLUSION: These data suggest that the patients with Asidan mutation show unique cognitive and affective characteristics different from other hereditary SCAs with exonal CAG expansion or MND.

Latent Mycobacterium tuberculosis-persistence, patience, and winning by waiting.

Mycobacterium tuberculosis is a globally successful pathogen due to its ability to persist for long periods of time unrecognized by the human immune system. The panoply of genes that allows the organism to enter latency and then re-emerge later during endogenous reinfection are now being elucidated. Novel antimicrobials and vaccines will need to target these mycobacterial pathogenic mechanisms to suceed against tuberculosis.

Behavior of glycolylated sialoglycans in the binding pockets of murine and human CD22.

Siglecs (sialic acid binding immunoglobulin (Ig)-like lectins) constitute a group of 15 human and 9 murine cell-surface transmembrane receptors belonging to the I-type lectin family, mostly expressed on innate immune cells and characterized by broadly similar structural features. Here, the prominent inhibitory CD22 (Siglec-2), well known in maintaining tolerance and preventing autoimmune responses on B cells, is studied in its human and murine forms in complex with sialoglycans. In detail, the role of the N-glycolyl neuraminic acid (Neu5Gc) moiety in the interaction with both orthologues was explored. The analysis of the binding mode was carried out by the combination of NMR spectroscopy, computational approaches, and CORCEMA-ST calculations. Our findings provide a first model of Neu5Gc recognition by h-CD22 and show a comparable molecular recognition profile by h- and m-CD22. These data open the way to innovative diagnostic and/or therapeutic methodologies to be used in the modulation of the immune responses.

Hospitalization risk following initiation of highly active antiretroviral therapy.

OBJECTIVES: While highly active antiretroviral therapy (HAART) decreases long-term morbidity and mortality, its short-term effect on hospitalization rates is unknown. The primary objective of this study was to determine hospitalization rates over time in the year after HAART initiation for virological responders and nonresponders. METHODS: Hospitalizations among 1327 HAART-naïve subjects in an urban HIV clinic in 1997-2007 were examined before and after HAART initiation. Hospitalization rates were stratified by virological responders (> or =1 log(10) decrease in HIV-1 RNA within 6 months after HAART initiation) and nonresponders. Causes were determined through International Classification of Diseases, 9th Revision (ICD-9) codes and chart review. Multivariate negative binomial regression was used to assess factors associated with hospitalization. RESULTS: During the first 45 days after HAART initiation, the hospitalization rate of responders was similar to their pre-HAART baseline rate [75.1 vs. 78.8/100 person-years (PY)] and to the hospitalization rate of nonresponders during the first 45 days (79.4/100 PY). The hospitalization rate of responders fell significantly between 45 and 90 days after HAART initiation and reached a plateau at approximately 45/100 PY from 91 to 365 days after HAART initiation. Significant decreases were seen in hospitalizations for opportunistic and nonopportunistic infections. CONCLUSIONS: The first substantial clinical benefit from HAART may be realized by 90 days after HAART initiation; providers should keep close vigilance at least until this time.

"Transmural air leak": a computed tomographic finding following endoscopic submucosal dissection of gastric tumors.

BACKGROUND AND STUDY AIMS: A small amount of free air, visible on CT but not on plain chest radiography, which appeared following endoscopic submucosal dissection (ESD) of a gastric neoplasm without endoscopically visible perforation, was defined as a "transmural air leak", and a prospective, consecutive entry study was performed to determine its incidence and clinical significance. PATIENTS AND METHODS: Between January 2006 and September 2008, ESD was performed for 246 gastric lesions in 246 consecutive patients. Abdominal CT scan was performed 1 day after ESD. In addition, chest radiography and blood biochemistry tests were performed at different time points before and after ESD. RESULTS: Two hundred and nineteen lesions (89 %) were curatively removed by ESD. Among the total of 246 patients, we encountered endoscopically visible perforation during ESD in 2 patients (0.8 %), and clinically suspected perforation diagnosed by the presence of free air on chest radiography but invisible during ESD in 3 patients (1 %), while transmural air leak was observed in another 33 (13 %). Air leak occurred in cases where resection size was larger, procedure time longer, and the muscularis propria on the ulcer base was exposed at the end of ESD. Patients with air leaks developed pyrexia at a higher rate than those without (36 % vs. 16 %, P = 0.018). These patients recovered with antibiotics and required no endoscopic or surgical intervention. The presence of an air leak did not affect the duration of hospital stay. CONCLUSIONS: A transmural air leak was observed in 13 % of the patients undergoing ESD. Larger resection size, prolonged procedure time, and exposure of the muscularis propria on the ulcer base were risk factors for transmural air leak, but the outcome of patients with this complication was good.

Relationship between environmental radiation and radioactivity and childhood thyroid cancer found in Fukushima health management survey.

Environmental radioactive contamination caused by the Fukushima Dai-ichi Nuclear Power Plant accident has aroused great concern regarding a possible increase in the incidence of childhood thyroid cancer. The ultrasound examinations were conducted immediately after the accident as part of the Fukushima Health Management Survey (FHMS), which is divided into the preliminary baseline survey (PBLS) and the full-scale survey (FSS). Some of their outcomes are reported regularly and made available to the public. We have detailed measurements of the air-dose rates and radioactive elements in soil in many places all over the Fukushima prefecture. To study the dose-response relationship, we begin with the assumption that the external and internal doses are correlated with the air-dose rate and the amount of 131I in soil, respectively. We then investigate the relationship between these estimated doses and the PBLS and FSS thyroid cancer cases. Our analysis shows that the dose-response curve with the FSS data clearly differs from that with the PBLS data. Finally, we consider the potential mitigating effects of evacuation from highly contaminated areas in both external and internal exposure scenarios.

Sustained positive impact on tuberculosis treatment outcomes of TB-HIV integrated care in Uganda.

To examine tuberculosis (TB) treatment outcomes from a long-term TB-HIV (human immunodeficiency virus) integrated model of care at the Infectious Diseases Institute Clinic, Kampala, Uganda. We included HIV-positive adults who were new TB cases initiated on anti-tuberculosis treatment between 2009 and 2015 during TB-HIV integration. Trends in TB treatment outcomes and TB-associated deaths were analyzed using respectively the χ² trend test and Kaplan-Meier methods. The analysis involved 1318 cases: most patients were female (>50%); the median age ranged from 34 to 36 years, and >60% were late presenters (CD4 count <200 cells/µl), with a median CD4 cell count of 100-146 cells/µl at TB diagnosis. TB treatment success (cured or treatment completed) was 67-76%. Loss to follow-up (LTFU) declined systematically from 7% in 2010 to 3.4% in 2015 (P < 0.01). Antiretroviral therapy (ART) initiation during the intensive phase improved from 47% in 2009 to 97% in 2015 (P < 0.01). The mortality rate was >15% over time, and the probability of death at month 2 of anti-tuberculosis treatment was 52% higher among late presenters than in early presenters (13% vs. 6%, P < 0.01). Significant LTFU improvement and prompt ART initiation could be due to well-implemented TB-HIV integration care; however, static TB-associated deaths may be due to late presentation. .

Xpert® MTB/RIF associated with improved treatment initiation among patients with smear-negative tuberculosis.

BACKGROUND: Delayed diagnosis and treatment initiation of smear-negative tuberculosis (TB) patients can lead to increased morbidity and mortality, particularly among those co-infected with the human immunodeficiency virus (HIV). OBJECTIVE: To compare TB treatment initiation among smear-negative presumptive TB patients in the 6 months before and after the introduction of Xpert® MTB/RIF testing at five rural tertiary hospitals in Uganda. METHODS: Patient records of the dates and results of sputum analysis were extracted from TB laboratory registers and linked to those on treatment initiation as indicated in the TB treatment registers. The proportion of smear-negative presumptive patients who initiated anti-tuberculosis treatment was compared before and after Xpert implementation using χ² tests. Time to treatment was analysed using Kaplan-Meier survival analysis. RESULTS: Records from 3658 patients were analysed, 1894 before and 1764 after the introduction of Xpert testing. After the introduction of Xpert, 25% (437/1764) of smear-negative presumptive TB patients underwent testing. The proportion initiated on anti-tuberculosis treatment increased from 5.9% (112/1894) to 10.8% (190/1764) (P < 0.01). However, 37% (32/87) of patients with a confirmed TB diagnosis did not initiate treatment. Time to TB treatment initiation improved from 8 to 3.5 days between the study periods. CONCLUSION: Xpert testing was associated with improved TB treatment initiation among smear-negative presumptive TB patients. Improved utilisation and linkage to treatment could improve the impact of this test on patient-centred outcomes.

Is the removal of osteosynthesis plates after orthognathic surgery necessary? Retrospective long-term follow-up study.

The removal of titanium miniplates is a controversial topic in oral and maxillofacial surgery. This retrospective study examined the timing of and reasons for titanium plate removal after orthognathic surgery. The study included 240 orthognathic surgery patients (71 male, 169 female; age range 16-55 years, mean 25.0±8.8 years) who had maxillofacial osteosynthesis plates inserted or inserted and then removed at the Division of Oral and Maxillofacial Surgery, Kagawa Prefectural Central Hospital, between April 2003 and March 2017. During the study period, a total of 717 miniplates were inserted in the 240 patients, and 71 of the patients (29.6%) had 236 plates (32.9%) removed. Ten patients (14.1%) had their plates removed within a year due to early complications. Although no patient had their plate removed due to complications at 1-5 years postoperative, a further 14 patients (19.7%) had their plates removed after more than 5 years of long-term follow-up due to plate-related complications. Complications requiring plate removal were evidently biphasic, occurring within 1 year after the operation and at ≥5 years after the operation. Therefore, after confirming postoperative bone healing, it is necessary to explain to patients the risks of plate removal and the importance of long-term follow-up.

Structure, chromosome location, and expression of the human smooth muscle (enteric type) gamma-actin gene: evolution of six human actin genes.

Recombinant phages that carry the human smooth muscle (enteric type) gamma-actin gene were isolated from human genomic DNA libraries. The amino acid sequence deduced from the nucleotide sequence matches those of cDNAs but differs from the protein sequence previously reported at one amino acid position, codon 359. The gene containing one 5' untranslated exon and eight coding exons extends for 27 kb on human chromosome 2. The intron between codons 84 and 85 (site 3) is unique to the two smooth muscle actin genes. In the 5' flanking region, there are several CArG boxes and E boxes, which are regulatory elements in some muscle-specific genes. Hybridization with the 3' untranslated region, which is specific for the human smooth muscle gamma-actin gene, suggests the single gene in the human genome and specific expressions in enteric and aortic tissues. From characterized molecular structures of the six human actin isoform genes, we propose a hypothesis of evolutionary pathway of the actin gene family. A presumed ancestral actin gene had introns at least sites 1, 2, and 4 through 8. Cytoplasmic actin genes may have directly evolved from it through loss of introns at sites 5 and 6. However, through duplication of the ancestral actin gene with substitutions of many amino acids, a prototype of muscle actin genes had been created. Subsequently, striated muscle actin and smooth muscle actin genes may have evolved from this prototype by loss of an intron at site 4 and acquisition of a new intron at site 3, respectively.

Effect of slow movement and stretch-shortening cycle on lower extremity muscle activity and joint moments during squat.

AIM: The purpose of the present study was to compare activity patterns of 8 muscles that cross the ankle, knee and hip joints under different conditions of squatting. METHODS: Ten male athletes performed squats at 3 different speeds (slow, normal, quick). Variables such as net moment and power about the joint were calculated during the descending and ascending phases of each squat. Using surface electrodes placed over the 8 lower extremity muscles, %iEMG was calculated during the ascending phase of each squat. RESULTS: In the descending phase, activities of the following 7 muscles were significantly greater for the quick squat (QS) than the normal squat (NS) or slow squat (SS): erector spinae (ES), gluteus maximus (Gmax), gluteus medius (Gmed), rectus femoris (RF), biceps femoris (BF), adductor longus (AL), and vastus lateralis (VL). Median frequency (MDF) of the Gmax muscle was significantly lower for NS than QS, and activity of the BF was significantly lower for NS than QS or SS. Mean moment of the hip joint was significantly lower for SS than QS. In the ascending phase, activities of the following 7 muscles were significantly greater for QS and NS than SS: ES, Gmax, Gmed, RF, BF, AL, and VL. MDF of the Gmax muscle was significantly lower for NS than QS, and the activity of the BF was significantly lower for NS than QS or SS. Mean moment of the hip joint was significantly higher for QS than SS or NS. Mean moment of the knee was significantly lower for SS than NS or QS. CONCLUSIONS: For QS, a stretch-shortening cycle increased the load on the Gmax. Mean muscle activity was less for SS than NS, and MDF was greater for SS than NS. These results suggest that SS mobilizes type-2 muscle fibers, despite the slow movement involved and the low risk of injury.

Clonic perseveration in the subacute stage of Japanese encephalitis.

We report a very rare case of Japanese encephalitis (JE) presenting with reversible stereotyped movement in the subacute stage. A 58-year-old woman presented with high fever, headache, nausea, vomiting, and consciousness disturbance. Cranial magnetic resonance imaging (MRI) of fluid attenuated inversion recovery (FLAIR) and T2-weighted image (WI) showed high intensity areas in the bilateral thalamus, caudate nucleus and hippocampus. She developed coma, convulsion, and ballism in the acute stage. One month after onset, she showed rhythmic, stereotyped, repetitive movements with hypoperfusion in the thalamus and frontal cortex on single photon emission computed tomography (SPECT). Three months later, her stereotyped movement improved accompanied by recovery of hypoperfusion in the thalamus and frontal cortex on SPECT. We speculated that her stereotyped movement was clonic perseveration due to frontal dysfunction induced by thalamofrontal disconnection.

Regulatory mechanisms of ethylene biosynthesis in response to various stimuli during maturation and ripening in fig fruit (Ficus carica L.).

In order to obtain a greater uniformity of maturation, the growth of the fig fruit (Ficus carica L.) can be stimulated by the application of either olive oil, ethrel/ethephon or auxin. The three treatments induce ethylene production in figs. In this study, we investigated the regulatory mechanisms responsible for oil, auxin and ethylene induced ethylene production in figs. The ethylene production in response to olive oil, auxin, and propylene treatments and during ripening were all induced by 1-methylcyclopropene (1-MCP) and inhibited by propylene indicating a negative feedback regulation mechanism. Three 1-aminocyclopropane-1-carboxylic acid (ACC) synthase genes (Fc-ACS1, Fc-ACS2 and Fc-ACS3) and one ACC oxidase gene (Fc-ACO1) were isolated and their expression patterns in response to either oil, propylene or auxin treatment in figs determined. The expression patterns of Fc-ACS1 and Fc-ACO1 were clearly inhibited by 1-MCP and induced by propylene in oil treated and ripe fruits indicating positive regulation by ethylene, whereas Fc-ACS2 gene expression was induced by 1-MCP and inhibited by propylene indicating negative regulation by ethylene. The Fc-ACS3 mRNA showed high level accumulation in the auxin treated fruit. The inhibition of Fc-ACS3 gene by 1-MCP in oil treated and in ripe fruits suggests that auxin and ethylene modulate the expression of this gene by multi-responsive signal transduction pathway mechanisms. We further report that the olive oil-induced ethylene in figs involves the ACC-dependent pathway and that multiple ethylene regulatory pathways are involved during maturation and ripening in figs and each specific pathway depends on the inducer/stimulus.

Induction of squamous cell carcinoma in the rat lung by 1,6-dinitropyrene.

The carcinogenicity of 1-nitropyrene [(1-NP) CAS: 5522-43-0] and 1,6-dinitropyrene [(1,6-DNP) CAS: 42397-64-8] was examined by their direct injection in a beeswax-tricaprylin vehicle into the lung of male F344/DuCrj rats. Of 28 rats given 0.15 mg of 1,6-DNP, 21 (75%) developed squamous cell carcinomas, 2 (7%) developed undifferentiated carcinomas, and 2 (7%) had squamous metaplasias in the lung by 72 weeks. In 32 rats that received 1.5 mg of 1-NP, neither carcinoma nor squamous metaplasia was induced. In all 19 rats (100%) given 0.5 mg of 3-methylcholanthrene [(MCA) CAS: 56-49-5], squamous cell carcinomas were induced earlier than in rats treated with 1,6-DNP. In 1 of 31 rats (3%) given the beeswax-tricaprylin vehicle only, squamous metaplasia was induced. Distant metastases of induced tumors were observed in 4 rats treated with 1,6-DNP and in 1 rat receiving MCA. Two lung tumors induced by 1,6-DNP were successively transplanted into the same strain of rats for 3 generations.