Repair of topoisomerase 1-induced DNA damage by tyrosyl-DNA phosphodiesterase 2 (TDP2) is dependent on its magnesium binding

Topoisomerases are enzymes that relax DNA supercoiling during replication and transcription. Camptothecin, a topoisomerase 1 (TOP1) inhibitor, and its analogs trap TOP1 at the 3'-end of DNA as a DNA-bound intermediate, resulting in DNA damage that can kill cells. Drugs with this mechanism of action are widely used to treat cancers. It has previously been shown that tyrosyl-DNA phosphodiesterase 1 (TDP1) repairs TOP1-induced DNA damage generated by camptothecin. In addition, tyrosyl-DNA phosphodiesterase 2 (TDP2) plays critical roles in repairing topoisomerase 2 (TOP2)-induced DNA damage at the 5'-end of DNA and in promoting the repair of TOP1-induced DNA damage in the absence of TDP1. However, the catalytic mechanism by which TDP2 processes TOP1-induced DNA damage has not been elucidated. In this study, we found that a similar catalytic mechanism underlies the repair of TOP1- and TOP2-induced DNA damage by TDP2, with Mg2+-TDP2 binding playing a role in both repair mechanisms. We show chain-terminating nucleoside analogs are incorporated into DNA at the 3'-end and abort DNA replication to kill cells. Furthermore, we found that Mg2+-TDP2 binding also contributes to the repair of incorporated chain-terminating nucleoside analogs. Overall, these findings reveal the role played by Mg2+-TDP2 binding in the repair of both 3'- and 5'-blocking DNA damage.

Using indocyanine green angiography to achieve complete engraftment of pectoralis major myocutaneous flaps

Although the pectoralis major myocutaneous (PMMC) flap is among the useful reconstructive materials following oral cancer ablation, this flap has an unstable blood circulation that could result in partial necrosis of the skin paddle. This report describes the usefulness of indocyanine green angiography (ICGA) to achieve complete engraftment of the PMMC flap. Five patients with oral cancer underwent reconstruction with a PMMC flap after cancer ablation. During the skin paddle design and flap elevation, the blood supply to the flap was assessed by ICGA. Areas of the skin paddle that showed no ICG fluorescence were excised. Consequently, prior to transfer to the recipient site, the blood supply to all flaps was confirmed with indocyanine green visible at the edge of the skin paddle, and complete engraftment was achieved without partial necrosis. Based on the results observed, ICGA would make a useful contribution to complete engraftment of the PMMC flap.

TB preventive treatment among pregnant women with HIV

BACKGROUND: The WHO recommends TB preventive treatment (TPT) for people living with HIV, including pregnant women. Uptake of this policy recommendation in this subpopulation and country alignment with WHO guidance is unclear.METHODS: We conducted a policy review in 38 WHO high TB and TB-HIV burden countries to assess if the uptake of TPT policy among pregnant women living with HIV was in line with the WHO´s 2018 Updated and Consolidated Guidelines for Programmatic Management for LTBI. Data sources included TB national guidelines and HIV/AIDS/ART national guidelines, complemented by results from a previous survey on policy uptake held at the WHO.RESULTS: Uptake of WHO policy to provide TB preventive treatment among women with HIV accessing antenatal care was moderate: 64% (23 of 36 countries) explicitly recommended at least one clinical guideline or policy recommendation on screening, testing or treatment of LTBI among pregnant women living with HIV. There was considerable variation between countries on the stages in pregnancy that TPT should be provided. Two countries (5%) provided clinical monitoring recommendations for pregnant women.CONCLUSIONS: There is moderate uptake of TPT policy for pregnant women with HIV. Failure to provide TPT as part of antenatal or prevention of mother-to-child services is a missed opportunity for TB control.

Clinical standards for the diagnosis, treatment and prevention of TB infection

BACKGROUND: Tuberculosis (TB) preventive therapy (TPT) decreases the risk of developing TB disease and its associated morbidity and mortality. The aim of these clinical standards is to guide the assessment, management of TB infection (TBI) and implementation of TPT.METHODS: A panel of global experts in the field of TB care was identified; 41 participated in a Delphi process. A 5-point Likert scale was used to score the initial standards. After rounds of revision, the document was approved with 100% agreement.RESULTS: Eight clinical standards were defined: Standard 1, all individuals belonging to at-risk groups for TB should undergo testing for TBI; Standard 2, all individual candidates for TPT (including caregivers of children) should undergo a counselling/health education session; Standard 3, testing for TBI: timing and test of choice should be optimised; Standard 4, TB disease should be excluded prior to initiation of TPT; Standard 5, all candidates for TPT should undergo a set of baseline examinations; Standard 6, all individuals initiating TPT should receive one of the recommended regimens; Standard 7, all individuals who have started TPT should be monitored; Standard 8, a TBI screening and testing register should be kept to inform the cascade of care.CONCLUSION: This is the first consensus-based set of Clinical Standards for TBI. This document guides clinicians, programme managers and public health officers in planning and implementing adequate measures to assess and manage TBI.

Roles for B[a]P and FICZ in subchondral bone metabolism and experimental temporomandibular joint osteoarthritis via the AhR/Cyp1a1 signaling axis

Bone loss due to smoking represents a major risk factor for fractures and bone osteoporosis. Signaling through the aryl hydrocarbon receptor (AhR) and its ligands contributes to both bone homeostasis and inflammatory diseases. It remains unclear whether the same AhR signaling axis affects the temporomandibular joint (TMJ). The aim of this study was to investigate possible mechanisms which mediate bone loss in the TMJ due to smoking. In particular, whether benzo[a]pyrene (B[a]P), a carcinogen of tobacco smoke, induces expression of the AhR target gene, Cyp1a1, in mandibular condyles. Possible functions of an endogenous ligand of FICZ, were also investigated in a TMJ-osteoarthritis (OA) mouse model. B[a]P was administered orally to wild-type and AhR-/- mice and bone metabolism was subsequently examined. TMJ-OA was induced in wild-type mice with forceful opening of the mouth. Therapeutic functions of FICZ were detected with μCT and histology. Exposure to B[a]P accelerated bone loss in the mandibular subchondral bone. This bone loss manifested with osteoclastic bone resorption and upregulated expression of Cyp1a1 in an AhR-dependent manner. In a mouse model of TMJ-OA, FICZ exhibited a dose-dependent rescue of mandibular subchondral bone loss by repressing osteoclast activity. Meanwhile, in vitro, pre-treatment with FICZ reduced RANKL-mediated osteoclastogenesis. B[a]P regulates mandibular subchondral bone metabolism via the Cyp1a1. The AhR ligand, FICZ, can prevent TMJ-OA by regulating osteoclast differentiation.

Early detection of Niemann-pick disease type C with cataplexy and orexin levels: continuous observation with and without Miglustat

Study objectives

Niemann-Pick type C (NPC) is an autosomal recessive and congenital neurological disorder characterized by the accumulation of cholesterol and glycosphingolipids. Symptoms include hepatosplenomegaly, vertical supranuclear saccadic palsy, ataxia, dystonia, and dementia. Some cases frequently display narcolepsy-like symptoms, including cataplexy which was reported in 26% of all NPC patients and was more often recorded among late-infantile onset (50%) and juvenile onset (38%) patients. In this current study, we examined CSF orexin levels in the 10 patients of NPC with and without cataplexy, which supports previous findings.

Methods

Ten patients with NPC were included in the study (5 males and 5 females). NPC diagnosis was biochemically confirmed in all 10 patients, from which 8 patients with NPC1 gene were identified. We compared CSF orexin levels among NPC, narcoleptic and idiopathic hypersomnia patients.

Results

Six NPC patients with cataplexy had low or intermediate orexin levels. In 4 cases without cataplexy, their orexin levels were normal. In 5 cases with Miglustat treatment, their symptoms stabilized or improved. For cases without Miglustat treatment, their conditions worsened generally. The CSF orexin levels of NPC patients were significantly higher than those of patients with narcolepsy-cataplexy and lower than those of patients with idiopathic hypersomnia, which was considered as the control group with normal CSF orexin levels.

Discussion

Our study indicates that orexin level measurements can be an early alert of potential NPC. Low or intermediate orexin levels could further decrease due to reduction in the neuronal function in the orexin system, accelerating the patients’ NPC pathophysiology. However with Miglustat treatment, the orexin levels stabilized or improved, along with other general symptoms. Although the circuitry is unclear, this supports that orexin system is indeed involved in narcolepsy-cataplexy in NPC patients.

Conclusion

The NPC patients with cataplexy had low or intermediate orexin levels. In the cases without cataplexy, their orexin levels were normal. Our study suggests that orexin measurements can serve as an early alert for potential NPC; furthermore, they could be a marker of therapy monitoring during a treatment.

Screening tools to exclude active pulmonary TB in high TB burden countries: systematic review and meta-analysis

<sec> <title>OBJECTIVE</title> To examine the use of symptoms, chest X-ray (CXR) abnormalities, and combinations of symptoms and CXR in excluding active pulmonary tuberculosis (TB) before treating for latent tuberculous infection (LTBI) in high TB burden countries. </sec> <sec> <title>METHODS</title> We updated a systematic review and meta-analysis of studies on the sensitivities, specificities, predictive values, diagnostic odds ratios and areas under the curve for index tests. The analysis was conducted using the hierarchical summary receiver operating characteristic method in R software. </sec> <sec> <title>RESULTS</title> We included 24 publications in the systematic review and meta-analysis. 'Any CXR abnormality' had the highest sensitivity (94.1%, 95%CI 85.8-97.7) among all index tests. 'CXR abnormality suggestive of TB' had a higher specificity (92.2%, 95%CI 89.7-94.1) than 'any CXR abnormality' (86.8%, 95%CI 79.7-91.7). The sensitivity for 'any TB symptom' was 73.0% (95%CI 64.1-80.4), while 'prolonged cough' of ≥2 weeks had a specificity of 94.3% (95%CI 92.2-95.9). There was no significant difference in the sensitivity and specificity of all screening tools stratified by human immunodeficiency virus (HIV) settings, with the exception of 'CXR abnormality suggestive of TB', which had a significantly higher sensitivity in low than in high HIV prevalence settings (effect estimate 2.26, 95%CI 0.69-3.82; P = 0.002). </sec> <sec> <title>CONCLUSION</title> In countries with a high TB burden, the absence of any TB symptom and any CXR abnormality can be used to exclude active pulmonary TB before initiating treatment for LTBI in household contacts aged ≥5 years of patients with bacteriologically confirmed pulmonary TB. </sec>.

Three-month weekly rifapentine plus isoniazid for tuberculosis preventive treatment: a systematic review

BACKGROUND

Uptake of preventive treatment for tuberculosis (TB) remains poor. A 3-month regimen of rifapentine (RPT) plus isoniazid (INH) (3HP) could facilitate its scale-up. We conducted a systematic review to assess the effects of 3HP compared with daily 6- or 9-month INH monotherapy.

METHODS

We searched the following databases to identify randomised controlled trials: PubMed, Embase, the Web of Science, Cochrane Central Register of Controlled Trials, three ongoing trial registers and conference abstracts up to 24 January 2017. Where possible, we pooled data using a random-effects model.

RESULTS

Four studies were included. Of those, we included two studies that compared 3HP with daily 6- or 9-month INH (6/9H) among adults with human immunodeficiency virus (HIV) co-infection, one among HIV-negative adults and one among predominantly HIV-negative children and adolescents. Risk of active TB was not significantly different between 3HP and 6/9H (risk ratio [RR] 0.73, 95%CI 0.23-2.29, in adults with HIV; RR 0.44, 95%CI 0.18-1.07, in adults without HIV; RR 0.13, 95%CI 0.01-2.54, in children and adolescents). Risk of hepatotoxicity was significantly lower in the 3HP group among adults with HIV (RR 0.26, 95%CI 0.12-0.55) and those without HIV (RR 0.16, 95%CI 0.10-0.27). 3HP was also associated with a higher completion rate in all subgroups.

CONCLUSIONS

HP was shown to have a preventive effect similar to that of INH monotherapy, with fewer adverse events and higher completion rates. 3HP can contribute significantly to the scale-up of preventive treatment.

Evidence of different climatic adaptation strategies in humans and non-human primates

To understand human evolution it is critical to clarify which adaptations enabled our colonisation of novel ecological niches. For any species climate is a fundamental source of environmental stress during range expansion. Mammalian climatic adaptations include changes in size and shape reflected in skeletal dimensions and humans fit general primate ecogeographic patterns. It remains unclear however, whether there are also comparable amounts of adaptation in humans, which has implications for understanding the relative importance of biological/behavioural mechanisms in human evolution. We compare cranial variation between prehistoric human populations from throughout Japan and ecologically comparable groups of macaques. We compare amounts of intraspecific variation and covariation between cranial shape and ecological variables. Given equal rates and sufficient time for adaptation for both groups, human conservation of non-human primate adaptation should result in comparable variation and patterns of covariation in both species. In fact, we find similar amounts of intraspecific variation in both species, but no covariation between shape and climate in humans, contrasting with strong covariation in macaques. The lack of covariation in humans may suggest a disconnect in climatic adaptation strategies from other primates. We suggest this is due to the importance of human behavioural adaptations, which act as a buffer from climatic stress and were likely key to our evolutionary success.

A Reporter System Evaluates Tumorigenesis, Metastasis, β-catenin/MMP Regulation, and Druggability

Cancer invasion, metastasis, and therapy resistance are the crucial phenomena in cancer malignancy. The high expression of matrix metalloproteinase 9 (MMP9) is a biomarker as well as a causal factor of cancer invasiveness and metastatic activity. However, a regulatory mechanism underlying MMP9 expression in cancer is not clarified yet. In addition, a new strategy for anticancer drug discovery is becoming an important clue. In the present study, we aimed (i) to develop a novel reporter system evaluating tumorigenesis, invasiveness, metastasis, and druggability with a combination of three-dimensional tumoroid model and Mmp9 promoter and (ii) to examine pharmacological actions of anticancer medications using this reporter system. High expression and genetic amplification of MMP9 were found in colon cancer cases. We found that proximal promoter sequences of MMP9 in murine and human contained conserved binding sites for transcription factors β-catenin/TCF/LEF, glucocorticoid receptor (GR), and nuclear factor kappa-B (NF-κB). The murine Mmp9 promoter (-569 to +19) was markedly activated in metastatic colon cancer cells and additionally activated by tumoroid formation and by β-catenin signaling stimulator lithium chloride. The Mmp9 promoter-driven fluorescent reporter cells enabled the monitoring of activities of MMP9/gelatinase, tumorigenesis, invasion, and metastasis in syngeneic transplantation experiments. We also demonstrated pharmacological actions as follows: dexamethasone and hydrocortisone, steroidal medications binding to GR, inhibited the Mmp9 promoter but did not inhibit tumorigenesis. On the contrary, antimetabolite 5-fluorouracil, a gold standard for colon cancer chemotherapy, inhibited tumoroid formation but did not inhibit Mmp9 promoter activity. Notably, antimalaria medication artesunate inhibited both tumorigenesis and the Mmp9 promoter in vitro, potentially through inhibition of β-catenin/TCF/LEF signaling. Thus, this novel reporter system enabled monitoring tumorigenesis, invasiveness, metastasis, key regulatory signalings such as β-catenin/MMP9 axis, and druggability. Impact Statement Cancer invasion and metastasis have been shown to be driven by matrix metalloproteinase 9 (MMP9), whose expression mechanism is not clarified yet. In addition, a new strategy for anticancer drug discovery is becoming important. We established a novel reporter system evaluating tumorigenesis, invasiveness, metastasis, and druggability with a combination of three-dimensional (3D) tumoroid model and Mmp9 promoter. Using this reporter system, we demonstrated pharmacological actions of anticancer medications such as antimetabolite 5-fluorouracil (5-FU) and antimalaria medication artesunate (ART), which inhibited both tumorigenesis and β-catenin/MMP regulatory signaling. Our study impacts the translational fields of oncology, drug discovery, and organoid model.

Policies and practices on the programmatic management of LTBI: a survey in the African Region

BACKGROUND

Although the management of latent tuberculous infection (LTBI) is a core component of the End TB Strategy, there is limited information about the status of implementation of such interventions in most African countries.

METHODS

A web-based survey involving the 47 countries of the African Region was conducted between November 2016 and April 2017.

RESULTS

The questionnaire was completed by 32/47 (68.1%) National TB Programme managers or their delegates. LTBI guidelines were available in four countries (12.5%), while 13 (40.6%) had an LTBI section in their national TB guidelines; there was no significant association with socio-economic conditions and funding allocation. LTBI diagnosis was mostly based on clinical evaluation to rule out active disease, rather than on systematic use of the tuberculin skin test. Respectively 23 (71.8%) and 17 countries (53.1%) reported providing treatment to child contacts aged <5 years and people living with the human immunodeficiency virus (PLHIV). Over two thirds of respondent countries had ongoing activities targeting at least one of the aforementioned high-risk groups. A recording and reporting system for LTBI-related data on child contacts and PLHIV was available in respectively 14 and 12 countries; 7 countries had an LTBI monitoring and evaluation plan.

CONCLUSIONS

These data suggest that greater effort is needed to appropriately scale up LTBI policies in the African Region.

Policies and practices on the programmatic management of latent tuberculous infection: global survey

SETTING

Global survey among low tuberculosis (TB) burden countries, which are primary target countries for the World Health Organization (WHO) guidelines on the programmatic management of latent tuberculous infection (LTBI).

OBJECTIVE

To perform a baseline assessment of policies and practices for the programmatic management of LTBI.

DESIGN

Online and paper-based pre-tested questionnaire filled out by national TB programme managers or their equivalents from 108 countries.

RESULTS

Of 74 respondent countries, 75.7% (56/74) had a national policy on LTBI. The majority of the countries (67/74, 90.5%) provided LTBI testing and treatment for child contacts of TB cases, while almost two thirds (49/74, 66%) reported provision of LTBI testing and treatment to people living with the human immunodeficiency virus (PLHIV). Six countries (8.1%) did not report providing LTBI management to child contacts and PLHIV. Among countries that reported both the availability of policy and practice of testing and treatment of LTBI for at-risk populations, a system for recording and reporting data was available in 62% (33/53) for child contacts and in 53% (21/40) for PLHIV.

CONCLUSION

Countries need to ensure that national LTBI policies and a standardised monitoring and evaluation system are in place to promote the programmatic management of LTBI.

The assessment of surgical and non-surgical treatment of stage II medication-related osteonecrosis of the jaw

Background

Non-surgical treatment has generally been recommended for stage II medication-related osteonecrosis of the jaw (MRONJ) in preference to surgery. However, non-surgical treatment is not empirically effective. The aim of this study was to evaluate whether surgical or non-surgical treatment leads to better outcomes for stage II MRONJ.

Material and Methods

In this retrospective study, surgery was performed in a total of 28 patients while 24 patients underwent non-surgical treatment. The outcomes of both treatment approaches after 6 months were evaluated and statistically compared. In addition, risk factors for surgical and non-surgical treatments were assessed for each.

Results

Surgical treatment in 25 patients (89.3%) resulted in success, with failure in 3 patients (10.7%). Non-surgical treatment was successful for 8 patients (33.3%) and failed in 16 patients (66.7%). There was therefore a significant difference between surgical and non-surgical treatment outcomes (P<0.01). Regarding risk factors, in non-surgical treatment primary diseases, medications, and drug holiday had a significant effect on outcomes (P<0.01). Risk factors for surgical treatment could not be clarified.

Conclusions

Surgical treatment is more effective than non-surgical treatment for stage II MRONJ, and drug holiday, primary disease, and medication constitute risk factors in non-surgical treatment.

Key words:Bisphosphonate, bisphosphonate-related osteonecrosis of the jaw, denosumab, management, medication-related osteonecrosis of the jaw.

Usefulness of 11C-methionine-PET for predicting the efficacy of carbon ion radiation therapy for head and neck mucosal malignant melanoma

The aim of this study was to determine whether l-methyl-[¹¹C]-methionine (MET) positron emission tomography (PET) allows the prediction of outcomes in patients with head and neck mucosal malignant melanoma treated with carbon ion radiation therapy (CIRT). This was a retrospective cohort study involving 85 patients who underwent a MET-PET or MET-PET/computed tomography (CT) examination before and after CIRT. MET uptake in the tumour was evaluated semi-quantitatively using the tumour-to-normal tissue ratio (TNR). Local recurrence, metastasis, and outcome predictions were studied in terms of TNR before CIRT (TNRpre), TNR after CIRT (TNRpost), and the TNR change ratio. Kaplan-Meier curves revealed significant differences between patients with higher TNRpre values and those with lower TNRpre values in regard to local recurrence, metastasis, and outcome (log-rank test P<0.0001 for all three). There were also significant differences in metastasis rates and outcomes between patients with higher and lower TNRpost values (log-rank test P=0.0105 and P=0.027, respectively). The Cox proportional hazards model revealed TNRpre to be a factor significantly influencing the risk of local recurrence (hazard ratio (HR) 29.0, P<0.001), risk of metastasis (HR 2.67, P=0.024), and the outcome (HR 6.3, P<0.001). MET-PET or MET-PET/CT is useful for predicting the outcomes of patients with head and neck mucosal malignant melanoma treated with CIRT.

Simeprevir plus sofosbuvir for eight or 12 weeks in treatment-naïve and treatment-experienced hepatitis C virus genotype 4 patients with or without cirrhosis

The OSIRIS study investigated efficacy and safety of simeprevir plus sofosbuvir for eight or 12 weeks in hepatitis C virus (HCV) genotype 4-infected patients with METAVIR F0-F4 fibrosis. Sixty-three patients (33 treatment-naïve and 30 peg-interferon/ribavirin (Peg-IFN/RBV)-experienced) enrolled in a partly randomized, open-label, multicentre, phase IIa study. Patients with F0-F3 fibrosis were randomized (1:1) into two groups (A1 and A2), stratified according to treatment experience and METAVIR score, to receive either eight weeks (Group A1, n=20) or 12 weeks (Group A2, n=20) of treatment. Patients with compensated cirrhosis (METAVIR F4) received 12 weeks of treatment (Group B, n=23). Treatment comprised simeprevir 150 mg and sofosbuvir 400 mg daily. The primary efficacy endpoint was sustained virologic response 12 weeks after planned end of treatment (SVR12). Safety and tolerability were assessed throughout. Overall, 92% (95% CI: 82-97) of patients achieved SVR12; 75% (15/20) in Group A1 and 100% in groups A2 and B. Patients who did not achieve SVR12 (n=5) experienced viral relapse during the first 32 days following treatment and were all prior Peg-IFN/RBV null responders. The most commonly reported treatment-emergent adverse events (TEAEs) were asymptomatic lipase increase (14%), pruritus (14%), headache (13%) and hyperbilirubinaemia (11%). No patients discontinued due to TEAEs. In conclusion, simeprevir plus sofosbuvir for 12 weeks achieved a 100% SVR rate in HCV genotype 4-infected patients with or without compensated cirrhosis (ClinicalTrials.gov: NCT02278419). The AE and laboratory profile were favourable and consistent with previous data for simeprevir plus sofosbuvir in eight- and 12-week regimens.

2D potential measurements by applying automatic beam adjustment system to heavy ion beam probe diagnostic on the Large Helical Device

Two-dimensional potential profiles in the Large Helical Device (LHD) were measured with heavy ion beam probe (HIBP). To measure the two-dimensional profile, the probe beam energy has to be changed. However, this task is not easy, because the beam transport line of LHD-HIBP system is very long (∼20 m), and the required beam adjustment consumes much time. To reduce the probe beam energy adjustment time, an automatic beam adjustment system has been developed. Using this system, required time to change the probe beam energy is dramatically reduced, such that two-dimensional potential profiles were able to be successfully measured with HIBP by changing the probe beam energy shot to shot.

Prediction of mean skin temperature for use as a heat strain scale by introducing an equation for sweating efficiency

The present paper made the heat balance equation (HBE) for nude or minimally clad subjects a linear function of mean skin temperature (t(sk)) by applying new equations for sweating efficiency (η(sw)) and thermoregulatory sweat rate (S(wR)). As the solution of the HBE, the equation predicting t(sk) was derived and used for a heat strain scale of subjects. The η(sw) was proportional to the reciprocal of S(w)/E(max) (S(w), sweat rate; E(max) maximum evaporative capacity) and the S(wR) was proportional to t(sk) with a parameter of the sweating capacity of the subject. The errors of predicted t(sk) from observations due to the approximation of η(sw) were examined based on experimental data conducted on eight young male subjects. The value of errors of t(sk) was -0.10 ± 0.42 °C (mean ± sample standard deviation (SSD)). We aim to apply the predicted t(sk) of a subject at a level of sweating capacity as a heat strain scale of a function of four environmental factors (dry- and wet-bulb temperatures, radiation, and air velocity) and three human factors (metabolic rate, sweating capacity, and clothing (≤0.2clo)).

The development and initial validation of a virtual dripping sweat rate and a clothing wetness ratio for use in predictive heat strain models

This paper applies the heat balance equation (HBE) for clothed subjects as a linear function of mean skin temperature (t sk ) by a new sweating efficiency (η sw ) and an approximation for the thermoregulatory sweat rate. The equation predicting t sk in steady state conditions was derived as the solution of the HBE and used for a predictive heat strain scale. The heat loss from the wet clothing (WCL) area was identified with a new variable of 'virtual dripping sweat rate VDSR' (S wdr ). This is a subject's un-evaporated sweat rate in dry clothing from the regional sweat rate exceeding the maximum evaporative capacity, and adds the moisture to the clothing, reducing the intrinsic clothing insulation. The S wdr allowed a mass balance analysis of the wet clothing area identified as clothing wetness (w cl ). The w cl was derived by combining the HBE at the WCL surface from which the evaporation rate and skin heat loss from WCL region are given. Experimental results on eight young male subjects wearing typical summer clothing, T-shirt and trousers verified the model for predicting t sk with WCL thermal resistance (R cl,w ) identified as 25 % of dry clothing (R cl,d ).

Negative predictive value of multiparametric MRI for prostate cancer detection: outcome of 5-year follow-up in men with negative findings on initial MRI studies

OBJECTIVE

To assess the clinical negative predictive value (NPV) of multiparametric MRI (mp-MRI) for prostate cancer in a 5-year follow-up.

MATERIALS AND METHODS

One hundred ninety-three men suspected of harboring prostate cancer with negative MRI findings were included. Patients with positive transrectal ultrasound (TRUS)-guided biopsy findings were defined as false-negative. Patients with negative initial TRUS-guided biopsy findings were followed up and only patients with negative findings by digital rectal examination, MRI, and repeat biopsy and no increase in PSA at 5-year follow-up were defined as "clinically negative". The clinical NPV of mp-MRI was calculated. For quantitative analysis, mean signal intensity on T2-weighted images and the mean apparent diffusion coefficient value on ADC maps of the initial MRI studies were compared between peripheral-zone (PZ) cancer and the normal PZ based on pathologic maps of patients who had undergone radical prostatectomy.

RESULTS

The clinical NPV of mp-MRI was 89.6% for significant prostate cancer. Small cancers, prostatitis, and benign prostatic hypertrophy masking prostate cancer returned false-negative results. Quantitative analysis showed that there was no significant difference between PZ cancer and the normal PZ.

CONCLUSION

The mp-MRI revealed a high clinical NPV and is a useful tool to rule out clinically significant prostate cancer before biopsy.

Identification and characterization of PDGFRα+ mesenchymal progenitors in human skeletal muscle

Fatty and fibrous connective tissue formation is a hallmark of diseased skeletal muscle and deteriorates muscle function. We previously identified non-myogenic mesenchymal progenitors that contribute to adipogenesis and fibrogenesis in mouse skeletal muscle. In this study, we report the identification and characterization of a human counterpart to these progenitors. By using PDGFRα as a specific marker, mesenchymal progenitors can be identified in the interstitium and isolated from human skeletal muscle. PDGFRα⁺ cells represent a cell population distinct from CD56⁺ myogenic cells, and adipogenic and fibrogenic potentials were highly enriched in the PDGFRα⁺ population. Activation of PDGFRα stimulates proliferation of PDGFRα⁺ cells through PI3K-Akt and MEK2-MAPK signaling pathways, and aberrant accumulation of PDGFRα⁺ cells was conspicuous in muscles of patients with both genetic and non-genetic muscle diseases. Our results revealed the pathological relevance of PDGFRα⁺ mesenchymal progenitors to human muscle diseases and provide a basis for developing therapeutic strategy to treat muscle diseases.