Imaging of muscle activity-induced morphometric changes in fibril network of myofascia by two-photon microscopy

Myofascia, deep fascia enveloping skeletal muscles, consists of abundant collagen and elastin fibres that play a key role in the transmission of muscular forces. However, understanding of biomechanical dynamics in myofascia remains very limited due to less quantitative and relevant approaches for in vivo examination. The purpose of this study was to evaluate the myofascial fibril structure by means of a quantitative approach using two-photon microscopy (TPM) imaging in combination with intravital staining of Evans blue dye (EBD), a far-red fluorescence dye, which potentially labels elastin. With focus on myofascia of the tibial anterior (TA) muscle, the fibril structure intravitally stained with EBD was observed at the depth level of collagen fibrous membrane above the muscle belly. The EBD-labelled fibril structure and orientation in myofascia indicated biomechanical responses to muscle activity and ageing. The orientation histograms of EBD-labelled fibrils were significantly modified depending upon the intensity of muscle activity and ageing. Moreover, the density of EBD-labelled fibrils in myofascia decreased with habitual exercise but increased with muscle immobilization or ageing. In particular, the diameter of EBD-labelled fibrils in aged mice was significantly higher. The orientation histograms of EBD-labelled fibrils after habitual exercise, muscle immobilization and ageing showed significant differences compared to control. Indeed, the histograms in bilateral TA myofascia of exercise mice made simple waveforms without multiple sharp peaks, whilst muscular immobilization or ageing significantly shifted a histogram with sustaining multiple sharp peaks. Therefore, the dynamics of fibre network with EBD fluorescence in response to the biomechanical environment possibly indicate functional tissue adaptation in myofascia. Furthermore, on the basis of the knowledge that neutrophil recruitment occurs locally in working muscles, we suggested the unique reconstruction mechanism involving neutrophilic elastase in the myofascial fibril structure. In addition to the elastolytic susceptibility of EBD-labelled fibrils, distinct immunoreactivities and activities of neutrophil elastase in the myofascia were observed after electric pulse stimulation-induced muscle contraction for 15 min. Our findings of EBD-labelled fibril dynamics in myofascia through quantitative approach using TPM imaging and intravital fluorescence labelling potentially brings new insights to examine muscle physiology and pathology.     

Knockout model reveals the role of Nischarin in mammary gland development,breast tumorigenesis and response to metformin treatment

Previously, our lab discovered the protein Nischarin and uncovered its role in regulating cell migration and invasion via its interactions with several proteins. We subsequently described a role for Nischarin in breast cancer, in which it is frequently underexpressed. To characterize Nischarin's role in breast tumorigenesis and mammary gland development more completely, we deleted a critical region of the Nisch gene (exons 7–10) from the mouse genome and observed the effects. Mammary glands in mutant animals showed delayed terminal end bud formation but did not develop breast tumors spontaneously. Therefore, we interbred the animals with transgenic mice expressing the mouse mammary tumor virus-polyoma middle T-antigen (MMTV-PyMT) oncogene. The MMTV-PyMT mammary glands lacking Nischarin showed increased hyperplasia compared to wild-type animal tissues. Furthermore, we observed significantly increased tumor growth and metastasis in Nischarin mutant animals. Surprisingly, Nischarin deletion decreased activity of AMPK and subsequently its downstream effectors. Given this finding, we treated these animals with metformin, which enhances AMPK activity. Here, we show for the first time, metformin activates AMPK signaling and inhibits tumor growth of Nischarin lacking PyMT tumors suggesting a potential use for metformin as a cancer therapeutic, particularly in the case of Nischarin-deficient breast cancers.     

The biodiversity of beneficial microbe-host mutualism: the case of rhizobia

Symbiotic nitrogen fixation is the main route for sustainable input of nitrogen into ecosystems. Nitrogen fixation in agriculture can be improved by inoculation of legume crops with suitable rhizobia. Knowledge of the biodiversity of rhizobia and of local populations is important for the design of successful inoculation strategies. Soybeans are major nitrogen-fixing crops in many parts of the world. Bradyrhizobial inoculants for soybean are very diverse, yet classification and characterization of strains have long been difficult. Recent genetic characterization methods permit more reliable identification and will improve our knowledge of local populations. Forage legumes form another group of agronomically important legumes. Research and extension policies valorizing rhizobial germplasm diversity and preservation, farmer training for proper inoculant use and legal enforcement of commercial inoculant quality have proved a successful approach to promoting the use of forage legumes while enhancing biological N₂ fixation. It is worth noting that taxonomically important strains may not necessarily be important reference strains for other uses such as legume inoculation and genomics due to specialization of the different fields. This article points out both current knowledge and gaps remaining to be filled for further interaction and improvement of a rhizobial commons.     

Cervical Cancer in Sub-Saharan Africa: A Multinational Population-Based Cohort Study of Care and Guideline Adherence

BackgroundCervical cancer (CC) is the most common female cancer in many countries of sub‐Saharan Africa (SSA). We assessed treatment guideline adherence and its association with overall survival (OS).MethodsOur observational study covered nine population‐based cancer registries in eight countries: Benin, Ethiopia, Ivory Coast, Kenya, Mali, Mozambique, Uganda, and Zimbabwe. Random samples of 44–125 patients diagnosed from 2010 to 2016 were selected in each. Cancer‐directed therapy (CDT) was evaluated for degree of adherence to National Comprehensive Cancer Network (U.S.) Guidelines.ResultsOf 632 patients, 15.8% received CDT with curative potential: 5.2% guideline‐adherent, 2.4% with minor deviations, and 8.2% with major deviations. CDT was not documented or was without curative potential in 22%; 15.7% were diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage IV disease. Adherence was not assessed in 46.9% (no stage or follow‐up documented, 11.9%, or records not traced, 35.1%). The largest share of guideline‐adherent CDT was observed in Nairobi (49%) and the smallest in Maputo (4%). In patients with FIGO stage I–III disease (n = 190), minor and major guideline deviations were associated with impaired OS (hazard rate ratio [HRR], 1.73; 95% confidence interval [CI], 0.36–8.37; HRR, 1.97; CI, 0.59–6.56, respectively). CDT without curative potential (HRR, 3.88; CI, 1.19–12.71) and no CDT (HRR, 9.43; CI, 3.03–29.33) showed substantially worse survival.ConclusionWe found that only one in six patients with cervical cancer in SSA received CDT with curative potential. At least one‐fifth and possibly up to two‐thirds of women never accessed CDT, despite curable disease, resulting in impaired OS. Investments into more radiotherapy, chemotherapy, and surgical training could change the fatal outcomes of many patients.Implications for PracticeDespite evidence‐based interventions including guideline‐adherent treatment for cervical cancer (CC), there is huge disparity in survival across the globe. This comprehensive multinational population‐based registry study aimed to assess the status quo of presentation, treatment guideline adherence, and survival in eight countries. Patients across sub‐Saharan Africa present in late stages, and treatment guideline adherence is remarkably low. Both factors were associated with unfavorable survival. This report warns about the inability of most women with cervical cancer in sub‐Saharan Africa to access timely and high‐quality diagnostic and treatment services, serving as guidance to institutions and policy makers. With regard to clinical practice, there might be cancer‐directed treatment options that, although not fully guideline adherent, have relevant survival benefit. Others should perhaps not be chosen even under resource‐constrained circumstances.     

Record linkage to correct under‐ascertainment of cancers in HIV cohorts: The Sinikithemba HIV clinic linkage project

The surveillance of HIV‐related cancers in South Africa is hampered by the lack of systematic collection of cancer diagnoses in HIV cohorts and the absence of HIV status in cancer registries. To improve cancer ascertainment and estimate cancer incidence, we linked records of adults (aged ≥ 16 years) on antiretroviral treatment (ART) enrolled at Sinikithemba HIV clinic, McCord Hospital in KwaZulu‐Natal (KZN) with the cancer records of public laboratories in KZN province using probabilistic record linkage (PRL) methods. We calculated incidence rates for all cancers, Kaposi sarcoma (KS), cervix, non‐Hodgkin's lymphoma and non‐AIDS defining cancers (NADCs) before and after inclusion of linkage‐identified cancers with 95% confidence intervals (CIs). A total of 8,721 records of HIV‐positive patients were linked with 35,536 cancer records. Between 2004 and 2010, we identified 448 cancers, 82% (n = 367) were recorded in the cancer registry only, 10% (n = 43) in the HIV cohort only and 8% (n = 38) both in the HIV cohort and the cancer registry. The overall cancer incidence rate in patients starting ART increased from 134 (95% CI 91–212) to 877 (95% CI 744–1,041) per 100,000 person‐years after inclusion of linkage‐identified cancers. Incidence rates were highest for KS (432, 95% CI 341–555), followed by cervix (259, 95% CI 179–390) and NADCs (294, 95% CI 223–395) per 100,000 person‐years. Ascertainment of cancer in HIV cohorts is incomplete, PRL is both feasible and essential for cancer ascertainment.     

Kaposi sarcoma-associated herpesvirus,HIV-1 and Kaposi sarcoma risk in black South Africans diagnosed with cancer during antiretroviral treatment rollout

Kaposi sarcoma-associated herpesvirus (KSHV) causes Kaposi sarcoma (KS). The risk of KS is amplified in HIV-immunosuppressed individuals and antiretroviral therapy (ART) reduces KS incidence. Reliable data on the relationship between these factors are lacking in Africa. We used questionnaires and serum from 7886 black South Africans (18-74 years) with incident cancer, recruited between 1995 and 2016. ART rollout started in 2004. We measured associations between KS, HIV-1 and KSHV before and after ART rollout. We measured seropositivity to HIV-1, KSHV latency-associated nuclear antigen (LANA) and glycoprotein (K8.1) and calculated case-control-adjusted odds ratios (OR_adj) and 95% confidence intervals (CI) in relation to KS and KSHV infection, before (1995-2004), early (2005-2009) and late (2010-2016) ART rollout periods. KSHV seropositivity among 1237 KS cases was 98%. Among 6649 controls, KSHV seropositivity was higher in males (OR_adj = 1.4 [95%CI 1.23-1.52]), in persons with HIV, (OR_adj = 4.2 [95%CI 3.74-4.73]) and lower in high school leavers (OR_adj = 0.7 [95%CI 0.59-0.83]). KSHV seropositivity declined over the three ART rollout periods (37%, 28% and 28%, P_trend < .001) coinciding with increases in high school leavers over the same periods (46%, 58% and 67%, P_trend < .001). HIV-1 seroprevalence increased from 10% in the pre-ART period to 22% in the late ART period (P_trend < .001). Compared to HIV-1 and KSHV seronegatives, KSHV seropositives yielded an OR for KS of 26 (95%CI 11-62) in HIV-1 seronegative participants and an OR of 2501 (95%CI 1083-5776) in HIV-1 seropositive participants. HIV-1 increases the risk of KS in those infected with KSHV by 100-fold. Declines in KSHV seroprevalence coincide with ART rollout and with improvements in educational standards and general hygiene.     

Kaposi's Sarcoma in HIV‐infected patients in South Africa: Multicohort study in the antiretroviral therapy era

The incidence of Kaposi's Sarcoma (KS) is high in South Africa but the impact of antiretroviral therapy (ART) is not well defined. We examined incidence and survival of KS in HIV‐infected patients enrolled in South African ART programs. We analyzed data of three ART programs: Khayelitsha township and Tygerberg Hospital programs in Cape Town and Themba Lethu program in Johannesburg. We included patients aged >16 years. ART was defined as a regimen of at least three drugs. We estimated incidence rates of KS for patients on ART and not on ART. We calculated Cox models adjusted for age, sex and time‐updated CD4 cell counts and HIV‐1 RNA. A total of 18,254 patients (median age 34.5 years, 64% female, median CD4 cell count at enrolment 105 cells/μL) were included. During 37,488 person‐years follow‐up 162 patients developed KS. The incidence was 1,682/100,000 person‐years (95% confidence interval [CI] 1,406–2,011) among patients not receiving ART and 138/100,000 person‐years (95% CI 102–187) among patients on ART. The adjusted hazard ratio comparing time on ART with time not on ART was 0.19 (95% CI 0.13–0.28). Low CD4 cell counts (time‐updated) and male sex were also associated with KS. Estimated survival of KS patients at one year was 72.2% (95% CI 64.9–80.2) and higher in men than in women. The incidence of KS is substantially lower on ART than not on ART. Timely initiation of ART is essential to prevent KS and KS‐associated morbidity and mortality in South Africa and other regions in Africa with a high burden of HIV.     

Gynaecologic and breast cancers in women living with HIV in South Africa: A record linkage study

Breast and gynaecologic cancers account for approximately half of all cancers diagnosed amongst women in South Africa, many of whom also live with HIV. We aimed to determine the incidence of and risk factors for developing breast and gynaecologic cancers in women living with HIV (WLHIV) in South Africa. This is a longitudinal analysis of the South African HIV Cancer Match study including women aged ≥15 years with two or more HIV-related laboratory tests. We used Cox proportional hazard models to determine the association of Human Papilloma Virus (HPV)-related and hormone-related gynaecologic cancer with patient- and municipal-level characteristics. From 3 447 908 women and 10.5 million years of follow-up, we identified 11 384 incident and 7612 prevalent gynaecologic and breast cancers. The overall crude incidence rate was 108/1 00 000 person-years (pyears) (95% confidence interval [CI]: 106-110), with the highest incidence observed for cervical cancer (70/1 00 000 pyears; 95% CI: 68.5-71.7). Low CD4 cell counts and high HIV RNA viral loads increased the risk of cervical and other HPV-related cancers. Age was associated with both HPV-related and hormone-related cancers. Women accessing health facilities in high socioeconomic position (SEP) municipalities were more likely to be diagnosed with HPV-related cancers and breast cancer than women accessing care in low SEP municipalities. It is important to improve the immunologic status of WLHIV as part of cancer prevention strategies in WLHIV. Cancer prevention and early detection programmes should be tailored to the needs of women ageing with HIV. In addition, SEP disparities in cancer diagnostic services have to be addressed.     

Thirteen cancers associated with HIV infection in a Black South African cancer patient population (1995-2016)

South Africa's HIV epidemic has evolved over time in terms of numbers of people living with HIV, access to antiretroviral treatment (ART) and age. These changes have profoundly influenced local cancer patterns. The Johannesburg Cancer Study has, over a period of 22 years (1995-2016), recruited over 20 000 incident black cancer patients who consented to provide answers to a questionnaire and blood samples (serum, DNA). This has presented a unique opportunity to examine the evolving association of HIV with cancer in Africa. We used logistic regression models to explore case-control associations between specific cancers and HIV, using participants with non-infection related cancers as controls. Using data of 20 835 cancer patients with confirmed HIV status, we found the following cancers to be associated with HIV: Kaposi's sarcoma (OR_adj; 95%CI): (99.1;72.6-135.1), non-Hodgkin lymphoma (11.3;9.3-13.6), cervical cancer (2.7;2.4-3.0), Hodgkin lymphoma (3.1;2.4-4.2), cancer of the eye/conjunctiva (18.7;10.1-34.7), anogenital cancers (anus [2.1;1.4-3.2], penis [5.4;2.7-10.5], vulva [4.8;3.5-6.4], vagina [5.5;3.0-10.2]), oropharyngeal cancer (1.6;1.3-1.9), squamous cell carcinoma of the skin (3.5;2.4-4.9), melanoma (2.0;1.2-3.5) and cancer of the larynx (1.7;1.3-2.4). Kaposi's sarcoma odds ratios increased from the pre-ART (1995-2004) to the early ART (2005-2009) period but declined in the late ART (2010-2016) period. Odds ratios for cancers of the eye/conjunctiva, cervix, penis and vulva continued to increase in recent ART periods. Our study confirms the spectrum of HIV-associated cancers found in other African settings. The odds ratios of conjunctival and HPV-related cancers continue to rise in the ART era as the HIV positive population ages.