High Financial Hardship among Patients with Advanced Ovarian Cancer

Ovarian cancer is considered the most fatal and costly gynecologic cancer. Although personalized therapies have improved ovarian cancer prognosis, they have resulted in increased financial toxicity concerns among this population. This study evaluated financial toxicity in patients with advanced ovarian cancer. Using secondary data from a study of barriers to palliative care, financial toxicity (FT) was measured through the Comprehensive Score for Financial Toxicity scale. Univariate and bivariate analyses were used to assess the relationship between selected demographic (i.e., age, race, ethnicity, education, place of birth, insurance type, yearly household income, employment status) and treatment-specific variables (i.e., years since diagnosis, surgery, chemotherapy, radiation, hormonal and targeted therapy) with clinically relevant financial toxicity. Characteristics were compared using Fisher's exact or chi squared tests. A total of 38 participants with advanced ovarian cancer were included in this study; 24% (n = 9) reported clinically significant FT. Income (p = .001), place of birth (p = .048) and employment status (p = .001) were related to FT. Study findings highlight that advanced ovarian cancer patients experience high FT, particularly those with low income, who are not able to work and were born outside the US. Further research using larger datasets and more representative samples is needed to inform intervention development and implementation.

Changes in Cancer Screening Knowledge Among a Prospective Cohort of Spanish-Speaking Hispanic Community Outreach Event Participants in Florida and Puerto Rico

The current study examined cancer prevention and early detection awareness (pre-workshop) and changes in knowledge (from pre- to post-workshop) among Hispanic/Latino (H/L) community members who participated in Spanish-language educational outreach events in Puerto Rico (PR) and Florida (FL). Spanish-language educational outreach events were comprised of an educational session lasting approximately 45-60 min and were delivered to groups in rural and urban community settings by a single trained community health educator (CHE). The research team assessed sociodemographic characteristics, personal and familial cancer health history, as well as awareness and knowledge (pre-test) of a range of cancer prevention and screening topics. Following the presentation, participants completed a post-test knowledge survey which also measured likelihood of engaging in cancer screening, cancer preventive behaviors, and cancer research as a result of information presented during the session. Change in the average knowledge score was evaluated using a paired samples t-test. Post-session likelihood of completing cancer screening and preventive behaviors and engaging in cancer research were examined using descriptive statistics and group/site comparisons. The percentage reporting awareness of screening procedures ranged from 33% (PSA test) to 79% (mammogram). H/L in PR reported higher percentage of stool blood test awareness when compared to H/L in FL (χ2(1)= 19.20, p<.001). The average knowledge score increased from 5.97 at pre-test to 7.09 at post-test (Cohen's d=0.69). The increase was significant across all participants (t(315)= 12.4, p<.001), as well as within the FL site (t(124)= 6.66, p<.001, d=0.59) and the PR site (t(190)=10.66, p<.001, d=0.77). Results from this study suggest that educational outreach events delivered to H/L community members by a CHE are valuable strategies to address challenges regarding cancer screening knowledge and engagement in multiple behaviors.

HPV vaccine recommendations by age: A survey of providers in federally qualified health centers

Clinician recommendation remains a critical factor in improving HPV vaccine uptake. Clinicians practicing in federally qualified health centers were surveyed between October 2021 and July 2022. Clinicians were asked how they recommended HPV vaccination for patients aged 9-10, 11-12, 13-18, 19-26, and 27-45 y (strongly recommend, offer but do not recommend strongly, discuss only if the patient initiates the conversation, or recommend against). Descriptive statistics were assessed, and exact binomial logistic regression analyses were utilized to examine factors associated with HPV vaccination recommendation in 9-10-y-old patients. Respondents (n = 148) were primarily female (85%), between the ages of 30-39 (38%), white, non-Hispanic (62%), advanced practice providers (55%), family medicine specialty (70%), and practicing in the Northeast (63%). Strong recommendations for HPV vaccination varied by age: 65% strongly recommended for ages 9-10, 94% for ages 11-12, 96% for ages 13-18, 82% for age 19-26, and 26% for ages 27-45 y. Compared to Women's Health/OBGYN specialty, family medicine clinicians were less likely to recommend HPV vaccination at ages 9-10 (p = .03). Approximately two-thirds of clinicians practicing in federally qualified health centers or safety net settings strongly recommend HPV vaccine series initiation at ages 9-10. Additional research is needed to improve recommendations in younger age groups.

Self-reported barriers to screening breast MRI among women at high risk for breast cancer

BACKGROUND

Annual screening breast MRI is recommended for women at high (≥ 20% lifetime) breast cancer risk, but is underutilized. Guided by the Health Services Utilization Model (HSUM), we assessed factors associated with screening breast MRI among high-risk women.

METHODS

From August 2020-January 2021, we recruited an online convenience sample of high-risk women ages 25-85 (N = 232). High-risk was defined as: pathogenic genetic mutation in self or first-degree relative; history of lobular carcinoma in situ; history of thoracic radiation; or estimated lifetime risk ≥ 20%. Participants self-reported predisposing factors (breast cancer knowledge, health locus of control), enabling factors (health insurance type, social support), need factors (perceived risk, screening-supportive social norms, provider recommendation), and prior receipt of screening breast MRI. Multivariable logistic regression analysis with backward selection identified HSUM factors associated with receipt of screening breast MRI.

RESULTS

About half (51%) of participants had received a provider recommendation for screening breast MRI; only 32% had ever received a breast MRI. Breast cancer knowledge (OR = 1.15, 95% CI = 1.04-1.27) and screening-supportive social norms (OR = 2.21, 95% CI = 1.64-2.97) were positively related to breast MRI receipt. No other HSUM variables were associated with breast MRI receipt (all p's > 0.1).

CONCLUSIONS

High-risk women reported low uptake of screening breast MRI, indicating a gap in guideline-concordant care. Breast cancer knowledge and screening-supportive social norms are two key areas to target in future interventions. Data were collected during the COVID-19 pandemic and generalizability of results is unclear. Future studies with larger, more heterogeneous samples are needed to replicate these findings.

Examining the perceived impact of the COVID-19 pandemic on cervical cancer screening practices among clinicians practicing in Federally Qualified Health Centers: A mixed methods study

Background

The COVID-19 pandemic led to reductions in cervical cancer screening and colposcopy. Therefore, in this mixed methods study we explored perceived pandemic-related practice changes to cervical cancer screenings in federally qualified health centers (FQHCs).

Methods

Between October 2021 and June 2022, we conducted a national web survey of clinicians (physicians and advanced practice providers) who performed cervical cancer screening in FQHCs in the United States during the post-acute phase of the COVID-19 pandemic, along with a sub-set of qualitative interviews via video conference, to examine perceived changes in cervical cancer screening practices during the pandemic.

Results

A total of 148 clinicians completed surveys; a subset (n=13) completed qualitative interviews. Most (86%) reported reduced cervical cancer screening early in the pandemic, and 28% reported continued reduction in services at the time of survey completion (October 2021- July 2022). Nearly half (45%) reported staff shortages impacting their ability to screen or track patients. Compared to clinicians in Obstetrics/Gynecology/Women's health, those in family medicine and other specialties more often reported reduced screening compared to pre-pandemic. Most (92%) felt that screening using HPV self-sampling would be very or somewhat helpful to address screening backlogs. Qualitative interviews highlighted the impacts of staff shortages and strategies for improvement.

Conclusions

Findings highlight that in late 2021 and early 2022, many clinicians in FQHCs reported reduced cervical cancer screening and of pandemic-related staffing shortages impacting screening and follow-up. If not addressed, reduced screenings among underserved populations could worsen cervical cancer disparities in the future.

Funding

This study was funded by the American Cancer Society, who had no role in the study's design, conduct, or reporting.

A cross-sectional survey examining clinician characteristics, practices, and attitudes associated with adoption of the 2019 American Society for Colposcopy and Cervical Pathology risk-based management consensus guidelines

BACKGROUND

The 2019 American Society for Colposcopy and Cervical Pathology (ASCCP) risk-based management consensus guidelines are the most recent national guidelines for the management of abnormal cervical cancer screening tests. These guidelines benefit patients by concentrating testing and treatment in those at highest cervical cancer risk. Adoption of guidelines often occurs slowly, with few studies examining the factors associated with guideline-adherent management of abnormal results.

METHODS

To elucidate the factors associated with the use of the 2019 ASCCP guidelines among clinicians who perform cervical cancer screening, physicians and advanced practice professionals who perform cervical cancer screening were cross-sectionally surveyed. Clinicians responded to screening vignettes with differing recommendations for management between the 2019 and prior management guidelines. Screening vignette 1 involved reduction of invasive testing on a low-risk patient; screening vignette 2 involved increased surveillance testing on a high-risk patient. Binomial logistic regression models determined the factors associated with the use of the 2019 guidelines.

RESULTS

A total of 1251 clinicians participated from across the United States. For screening vignettes 1 and 2, guideline-adherent responses were given by 28% and 36% of participants, respectively. Management recommendations differed by specialty and were incorrect in different situations: there was inappropriate invasive testing by obstetrics and gynecology physicians (vignette 1) and inappropriate discontinuation of screening by family and internal medicine physicians (vignette 2). Regardless of their chosen response, over half erroneously believed they were guideline adherent.

CONCLUSIONS

Many clinicians who believe they are following appropriate guidelines may not realize their management strategy is inconsistent with the 2019 guidelines. Education initiatives tailored to clinician specialty could address the understanding of current guidelines, encourage the use of updated guidelines, maximize patient benefits, and minimize harms.

PLAIN LANGUAGE SUMMARY

The 2019 American Society for Colposcopy and Cervical Pathology risk-based management consensus guidelines are the most recent national guidelines for abnormal cervical cancer screening test management. We surveyed over 1200 obstetrics and gynecology (OB/GYN), family medicine, and internal medicine physicians and advanced practice providers about their screening and abnormal results follow-up practices in relation to guidelines. Few clinicians are following the 2019 guidelines. Management recommendations differed by clinician specialty and were incorrect in different situations: there was inappropriate invasive testing by OB/GYN physicians and inappropriate screening discontinuation by family and internal medicine physicians. Education tailored by clinician specialty could address the understanding of current guidelines, encourage the use of updated guidelines, maximize patient benefits, and minimize harms.

Examining the association of clinician characteristics with perceived changes in cervical cancer screening and colposcopy practice during the COVID-19 pandemic: a mixed methods assessment

Background

The COVID-19 pandemic led to reductions in cervical cancer screening and colposcopy. Therefore, in this mixed method study we explored perceived pandemic-related practice changes to cervical cancer screenings and colposcopies.

Methods

In 2021, a national sample of 1251 clinicians completed surveys, including 675 clinicians who performed colposcopy; a subset (n=55) of clinicians completed qualitative interviews.

Results

Nearly half of all clinicians reported they were currently performing fewer cervical cancer screenings (47%) and colposcopies (44% of those who perform the procedure) than before the pandemic. About one-fifth (18.6%) of colposcopists reported performing fewer LEEPs than prior to the pandemic. Binomial regression analyses indicated that older, as well as internal medicine and family medicine clinicians (compared to OB-GYNs), and those practicing in community health centers (compared to private practice) had higher odds of reporting reduced screening. Among colposcopists, internal medicine physicians and those practicing in community health centers had higher odds of reporting reduced colposcopies. Qualitative interviews highlighted pandemic-related care disruptions and lack of tracking systems to identify overdue screenings.

Conclusions

Reductions in cervical cancer screening and colposcopy among nearly half of clinicians more than 1 year into the pandemic raise concerns that inadequate screening and follow-up will lead to future increases in preventable cancers.

Funding

This study was funded by the American Cancer Society, who had no role in the study's design, conduct, or reporting.

"It doesn't really apply to what I'm going through": a mixed-methods study of barriers to palliative care among patients with advanced ovarian cancer

PURPOSE

Palliative care aims to provide symptom relief and general support for patients with serious illness. Despite experiencing significant treatment side effects, specialty palliative care is under-utilized by patients with advanced ovarian cancer. We explored barriers to palliative care in this population.

METHODS

We conducted a sequential mixed-methods study. Qualitative: we interviewed patients with advanced ovarian cancer (N = 7). Guided by the Social Ecological Model (SEM), interviews assessed intrapersonal, interpersonal, organizational, and policy-level barriers to receipt of specialty palliative care. Interviews were audio-recorded, transcribed, and analyzed with directed content analysis. Quantitative: patients with advanced ovarian cancer (N = 38) completed self-report surveys assessing knowledge about, attitudes towards, and prior experiences with specialty palliative care. Descriptive statistics were used to characterize survey responses.

RESULTS

Qualitative analysis identified barriers to specialty palliative care at each SEM level. Intrapersonal factors (e.g., knowledge, attitudes) were most frequently discussed. Other common barriers included insurance coverage and distance/travel time. Survey responses indicated most participants were aware of palliative care (74%) but had mixed attitudes towards palliative care and did not feel they needed for palliative care. No survey respondents had received a physician recommendation for palliative care, and a sizable minority (29%) thought palliative care referral should only take place when patients have no remaining treatment options.

CONCLUSION

Among patients with advanced ovarian cancer, barriers to specialty palliative care exist at multiple levels. Our results underscore the potential value of a multilevel intervention to support receipt of palliative care in this population.

Socioeconomic disparities in psychosocial service recommendation and receipt among young Black breast cancer survivors

PURPOSE

Black cancer survivors are less likely to receive desired psychological services than non-Hispanic White survivors. Black cancer survivors with low socioeconomic status may face additional barriers to receipt of psychological services. This study examined socioeconomic disparities in psychological service recommendation, attempts to access, and receipt among Black breast cancer (BC) survivors.

METHODS

Black BC survivors (n = 249) completed surveys at baseline (T1) and follow-up (T2; M 1.6 years post-T1). At T1, participants reported socioeconomic characteristics (employment, income, insurance, and education) and psychological symptoms (hospital anxiety and depression scale [HADS]). Self-reported address was used to identify area deprivation index (ADI), a composite measure of neighborhood socioeconomic disadvantage (least disadvantaged = 1; most disadvantaged = 10). At T2, participants reported provider recommendations for, attempts to access, and receipt of psychological services. Logistic regressions examined relationships between socioeconomic characteristics and psychological service variables, controlling for baseline psychological symptoms.

RESULTS

In multivariable analyses, being employed was associated with a lower likelihood of attempts to access (OR = 0.25) and receipt of (OR = 0.37) psychological services, above and beyond the effect of psychological symptoms. Univariate analyses demonstrated that participants from more disadvantaged areas (i.e., higher ADI) were more likely to receive psychological services (OR = 1.20), but this effect became non-significant in multivariable analyses.

CONCLUSION

Results highlight the importance of an intersectional perspective in considering mental health care disparities; both race/ethnicity and socioeconomic status should be incorporated when considering barriers and facilitators of psychological care.

Barriers and facilitators to taking CDK4/6 inhibitors among patients with metastatic breast cancer: a qualitative study

PURPOSE

Most studies of adherence to treatment for breast cancer have focused on early-stage patients. Findings from these studies may not generalize to patients with metastatic breast cancer (MBC). The objective of this study was to identify barriers and facilitators of adherence to cyclin-dependent kinase 4/6 (CDK4/6) inhibitors among patients with MBC, guided by the social ecologic model (SEM).

METHODS

Patients with MBC (N = 25), their caregivers (N = 9), and oncology providers (N = 13) completed semi-structured qualitative interviews exploring their experiences with CDK4/6 inhibitors. Interviews were audio-recorded, transcribed verbatim, and analyzed by three raters using a combined deductive and inductive approach.

RESULTS

Qualitative analysis identified barriers and facilitators of adherence at each SEM level. Intrapersonal and interpersonal factors were most frequently discussed. Intrapersonal factors included knowledge/beliefs about CDK4/6 inhibitors, side effects, and establishing a routine. Interpersonal factors included effective communication with/coordination by the care team, support from family and friends, and information from other patients with MBC. Although less frequently discussed, policy factors (i.e., cost of CDK4/6 inhibitors) were of great concern to patients, caregivers, and providers.

CONCLUSION

Barriers to adherence to CDK4/6 inhibitors exist at multiple levels. Our results underscore the potential value of a multilevel intervention (e.g., patient education, evidence-based strategies for symptom management, tips for open and assertive communication with providers, information about financial resources/support available, and so on) to support adherence in this population.

Health Literacy in Surgical Oncology Patients: An Observational Study at a Comprehensive Cancer Center

BACKGROUND

Low health literacy is associated with increased resource use and poorer outcomes in medical and surgical patients with various diseases. This observational study was designed to determine (1) the prevalence of low health literacy among surgical patients with cancer at an NCI-designated Comprehensive Cancer Center (CCC), and (2) associations between health literacy and clinical outcomes.

METHODS

Patients receiving surgery (N=218) for gastrointestinal (60%) or genitourinary cancers (22%) or sarcomas (18%) were recruited during their postsurgical hospitalization. Patients self-reported health literacy using the Brief Health Literacy Screening Tool (BRIEF). Clinical data (length of stay [LoS], postacute care needs, and unplanned presentation for care within 30 days) were abstracted from the electronic medical records 90 days after surgery. Multivariate linear and logistic regressions were used to examine the relationship between health literacy and clinical outcomes, adjusting for potential confounding variables.

RESULTS

Of 218 participants, 31 (14%) showed low health literacy (BRIEF score ≤12). In regression analyses including 212 patients with complete data, low health literacy significantly predicted LoS (β = -1.82; 95% CI, -3.00 to -0.66; P=.002) and postacute care needs (odds ratio [OR], 0.25; 95% CI, 0.07-0.91). However, health literacy was not significantly associated with unplanned presentation for care in the 30 days after surgery (OR, 0.51; 95% CI, 0.20-1.29).

CONCLUSIONS

This study demonstrates the prevalence of low health literacy in a surgical cancer population at a high-volume NCI-designated CCC and its association with important clinical outcomes, including hospital LoS and postacute care needs. Universal screening and patient navigation may be 2 approaches to mitigate the impact of low health literacy on postsurgical outcomes.

46 Primary Care Practitioners Have A High Level of Satisfaction with The Current Breast Referral Pathway but The Majority Would Support A Change to Patient Self-Referral

Aim

Currently, patients must consult with a primary care practitioner (PCP) prior to being referred to secondary care breast services. A change to patient self-referral would arguably reduce primary care workload, improve access for patients, and allow breast units to allocate resources more appropriately; no data currently supports this. This study aims to explore PCP's views on breast referral, evaluate the community breast workload, and to investigate the impact of COVID-19 on referral rates.

Method

An electronic survey was designed on SurveyMonkey.com which aimed to collect both quantitative and qualitative data. The weblink to the survey was sent out via two electronic newsletters. Participants were asked: their role and gender, their level of confidence surrounding breast care, details surrounding their breast workload, how they felt COVID-19 had affected their referral rates, their level of satisfaction with the current pathway, and their opinions on a potential change to patient self-referral.

Results

79 responses were received. PCPs estimated that 7.0% (median) of their total consultations were regarding a breast-related issue and that COVID-19 had not had a significant impact on the rate of referral to breast units (P = 0.75). 84.8% of PCPs were satisfied with the current referral pathway. Whilst 74.5% felt a change to patient self-referral would benefit patients and primary care services, their free text comments highlighted some of their reservations.

Conclusions

PCPs have a high level of satisfaction with the current breast referral pathway, but the majority would be open to a change to patient self-referral to specialist breast units.

"I think that a brief conversation from their provider can go a very long way": Patient and provider perspectives on barriers and facilitators of genetic testing after ovarian cancer

OBJECTIVE

Identify predisposing, enabling, and reinforcing factors impacting genetic counseling/testing among ovarian cancer patients guided by Green and Kreuter's PRECEDE-PROCEED model.

METHODS

Gynecologic oncology providers (N = 4), genetic counselors (N = 4), and ovarian cancer patients (N = 9) completed semi-structured qualitative interviews exploring participants' knowledge of and experiences with genetic counseling/testing. Interviews were audio recorded, transcribed verbatim, and analyzed using inductive content analysis by two independent raters.

RESULTS

Thematic analysis identified predisposing, enabling, and reinforcing factors impacting referral for and uptake of genetic counseling/testing. Predisposing factors included participant's knowledge, beliefs, and attitudes related to genetic counseling/testing. Both patients and providers also cited that insurance coverage and out-of-pocket cost are major concerns for ovarian cancer patients considering genetic testing. Finally, both patients and providers emphasized that genetic counseling/testing would provide additional information to an ovarian cancer patient. While providers emphasized that genetic testing results were useful for informing a patient's personal treatment plan, patients emphasized that this knowledge would be beneficial for their family members.

CONCLUSION

Barriers to genetic testing for ovarian cancer patients exist at multiple levels, including the patient (e.g., knowledge, attitudes), the provider (e.g., workload, availability of services), the institution (e.g., difficulty with referrals/scheduling), and the healthcare system (e.g., insurance/cost). Interventions aiming to increase genetic testing among ovarian cancer patients will likely need to target multiple levels of influence. Future quantitative studies are needed to replicate these results. This line of work will inform specific multilevel intervention strategies that are adaptable to different practice settings, ultimately improving guideline concordant care.

Genetic Consequences of the Transatlantic Slave Trade in the Americas

According to historical records of transatlantic slavery, traders forcibly deported an estimated 12.5 million people from ports along the Atlantic coastline of Africa between the 16th and 19th centuries, with global impacts reaching to the present day, more than a century and a half after slavery's abolition. Such records have fueled a broad understanding of the forced migration from Africa to the Americas yet remain underexplored in concert with genetic data. Here, we analyzed genotype array data from 50,281 research participants, which-combined with historical shipping documents-illustrate that the current genetic landscape of the Americas is largely concordant with expectations derived from documentation of slave voyages. For instance, genetic connections between people in slave trading regions of Africa and disembarkation regions of the Americas generally mirror the proportion of individuals forcibly moved between those regions. While some discordances can be explained by additional records of deportations within the Americas, other discordances yield insights into variable survival rates and timing of arrival of enslaved people from specific regions of Africa. Furthermore, the greater contribution of African women to the gene pool compared to African men varies across the Americas, consistent with literature documenting regional differences in slavery practices. This investigation of the transatlantic slave trade, which is broad in scope in terms of both datasets and analyses, establishes genetic links between individuals in the Americas and populations across Atlantic Africa, yielding a more comprehensive understanding of the African roots of peoples of the Americas.

Abstract D022: A novel strategy to assess impact of community outreach and education activities for Hispanic communities: The preliminary results of the CONTINUAR protocol

Introduction: Cancer is a leading cause of death among Hispanic/Latinos (H/L) in the United States and Puerto Rico. Educational interventions to improve health behavior uptake and adherence for primary and secondary prevention could reduce dis parities among H/L. While there has been an investment of time and resources to implement health education programs to reach H/L in diverse community settings, little is known about their intermediate outcomes and long-term behavioral impact. Innovative and systematic tracking of event participants can address the gap in knowledge. This report presents the development and preliminary results from the protocol established to track and assess short, intermediate, and long-term changes in cancer prevention knowledge, beliefs, intentions; interest in future research participation; and, ultimately, behavior changes among educational workshop attendees. Methods: The Ponce Health Sciences University – Moffitt Cancer Center Partnership’s Outreach Core provides cancer education to Spanish-preferring audiences in Tampa, FL, and Puerto Rico. We implemented a community outreach protocol (CONTINUAR) to track and assess individual’s cancer prevention knowledge, beliefs, and intentions before and after educational events using an innovative community cohort approach and longitudinal pre/post-test design. Demographic information and personal/familial risk factors were assessed at baseline. All sessions included education about age, gender, and risk-appropriate cancer screenings. Event attendees were asked if they were interested in completing follow-up surveys at 12 and 24 months. Interested participants were consented via an information sheet. They also provided contact information and preferred contact modality for follow-up surveys. Results: Across two events with 449 community members, 223 (49.7%) completed pre/post assessments and 187 (41.6%) enrolled in the study. All event participants considered themselves H/L and 88% stated Spanish as their preferred language. The median age was 60. A paired samples t-test compared knowledge gained regarding current early detection screening guidelines before and after the educational activity, t(222) = 7.97, p&lt;0.001. Most participants surveyed after the workshop reported intention to: speak with a healthcare provider about cancer screening tests (96.2%), get screening for cancer (97.2%), discuss cancer screening with family or friends (95.4%), increase their physical activity (96.2%), participate in research studies (77.1%), and donate tissue to a biobank (68.9%). Conclusion: The results demonstrated the feasibility to enroll participants and an improvement in short-term knowledge. The success of this ongoing longitudinal effort remains to be realized as 12 and 24 months follow-ups aim to assess whether participants are indeed engaged in new health behaviors or accessed cancer-related early detection screening.

Citation Format: Jomar Lopez, Jennifer Garcia, Cynthia Cortes, McKenzie McIntyre, Laura Moreno, Jessica McIntyre, Steven K Sutton, Eida Castro, Julio Jimenez, Clement K Gwede, Susan T Vadaparampil. A novel strategy to assess impact of community outreach and education activities for Hispanic communities: The preliminary results of the CONTINUAR protocol [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr D022.

Patterns and predictors of genetic referral among ovarian cancer patients at a National Cancer Institute-Comprehensive Cancer Center

Germline mutations (eg, BRCA1/2) have prognostic and treatment implications for ovarian cancer (OVCA) patients. Thus, national guidelines recommend genetic testing for OVCA patients. The present study examines patterns and predictors of genetics referral in OVCA patients. Electronic medical record data were abstracted retrospectively from 557 OVCA patients treated from 1 January 2001 to 31 December 2015. Logistic regression models identified sociodemographic characteristics, disease/treatment characteristics, family history data, provider characteristics, and survival data that predicted genetics referral. Overall, 27.5% of patients received referral. Eleven variables predicting referral were selected during stepwise regression: younger age, White race, not having private insurance, professional school education, year of OVCA diagnosis, platinum sensitivity, female gynecologic oncologist, chemotherapy administered by a gynecologic oncologist, clinical trial enrollment, longer overall survival, and family history of OVCA. Genetics referral among OVCA patients was similar to rates reported nationwide. Unique predictive factors will contribute to quality improvement and should be validated at a multi-institutional level to ensure guideline concordant care is provided to all OVCA patients. Future research should identify both patient-level and provider-level factors associated with genetics referral.

Application of recombinant antigen 5 allergens from seven allergy-relevant Hymenoptera species in diagnostics

BACKGROUND

Hymenoptera stings can cause severe anaphylaxis in untreated venom-allergic patients. A correct diagnosis regarding the relevant species for immunotherapy is often hampered by clinically irrelevant cross-reactivity. In vespid venom allergy, cross-reactivity between venoms of different species can be a diagnostic challenge. To address immunological IgE cross-reactivity on molecular level, seven recombinant antigens 5 of the most important Vespoidea groups were assessed by different diagnostic setups.

METHODS

The antigens 5 of yellow jackets, hornets, European and American paper wasps, fire ants, white-faced hornets, and Polybia wasps were recombinantly produced in insect cells, immunologically and structurally characterized, and their sIgE reactivity assessed by ImmunoCAP, ELISA, cross-inhibition, and basophil activation test (BAT) in patients with yellow jacket or Polistes venom allergy of two European geographical areas.

RESULTS

All recombinant allergens were correctly folded and structural models and patient reactivity profiles suggested the presence of conserved and unique B-cell epitopes. All antigens 5 showed extensive cross-reactivity in sIgE analyses, inhibition assays, and BAT. This cross-reactivity was more pronounced in ImmunoCAP measurements with venom extracts than in sIgE analyses with recombinant antigens 5. Dose-response curves with the allergens in BAT allowed a differentiated individual dissection of relevant sensitization.

CONCLUSIONS

Due to extensive cross-reactivity in various diagnostic settings, antigens 5 are inappropriate markers for differential sIgE diagnostics in vespid venom allergy. However, the newly available antigens 5 from further vespid species and the combination of recombinant allergen-based sIgE measurements with BAT represents a practicable way to diagnose clinically relevant sensitization in vespid venom allergy.

Pollen derived low molecular compounds enhance the human allergen specific immune response in vivo

BACKGROUND

Besides allergens, pollen release bioactive, low molecular weight compounds that modulate and stimulate allergic reactions. Clinical relevance of these substances has not been investigated to date.

OBJECTIVE

To elucidate the effect of a non-allergenic, low molecular weight factors from aqueous birch pollen extracts (Bet-APE < 3 kDa) on the human allergic immune response in vivo.

METHODS

Birch and grass pollen allergic individuals underwent skin prick testing with allergen alone, allergen plus Bet-APE < 3 kDa, or allergen plus pre-identified candidate substances from low molecular pollen fraction. Nasal allergen challenges were performed in non-atopic and pollen allergic individuals using a 3 day repeated threshold challenge battery. Subjects were either exposed to allergen alone or to allergen plus Bet-APE< 3 kDa. Local cytokine levels, nasal secretion weights, nasal congestion and symptom scores were determined.

RESULTS

Skin prick test reactions to pollen elicited larger weals when allergens were tested together with the low molecular weight compounds from pollen. Similar results were obtained with candidate pollen-associated lipid mediators. In nasal lining fluids of allergic patients challenged with allergen plus Bet-APE < 3 kDa, IL-8 and IgE was significantly increased as compared to allergen-only challenged patients. These patients also produced increased amounts of total nasal secretion and reported more severe rhinorrhea than the allergen-only challenged group.

CONCLUSIONS

Low molecular compounds from pollen enhance the allergen specific immune response in the skin and nose. They are therefore of potential clinical relevance in allergic patients.

The major royal jelly proteins 8 and 9 (Api m 11) are glycosylated components of Apis mellifera venom with allergenic potential beyond carbohydrate-based reactivity

BACKGROUND

As hymenoptera venoms are one of the allergen sources causing the highest incidence of anaphylaxis and sometimes fatal consequences, the detailed characterization of all venom allergens is imperative for design of component-resolved diagnostic approaches and improved intervention strategies.

OBJECTIVE

Our aim was the immunochemical characterization of major royal jelly proteins (MRJP) 8 and 9, both components identified in honeybee venom (HBV) and putative allergens.

METHODS

Both MRJPs were recombinantly produced as soluble differentially glycosylated proteins providing a defined degree of reactivity to cross-reactive carbohydrate determinants (CCD) in insect cells. Allergen-specific IgE(sIgE) reactivity of HBV-allergic patients was analysed by ELISA and immunoblotting.

RESULTS

MRJP8 and MRJP9 were identified as venom components by MS-based proteomic analyses. In a population of 47 HBV-allergic patients, reactivities with CCD-carrying MRJPs were in the range of 56% (61%), underlining the contribution of CCDs to allergen-binding. Beyond CCD-reactivity, 15% of patients showed sIgE reactivity with MRJP8 and 34% with MRJP9 respectively. These reactivities roughly in the range of Api m 2 render the MRJPs minor, but important allergens.

CONCLUSION AND CLINICAL RELEVANCE

The glycosylated MRJP8 and MRJP9 of HBV have IgE-sensitizing potential in HBV-allergic patients beyond CCD reactivity and have to be considered as allergens, which might be potentially important for a fraction of venom allergic patients. They are valuable tools to elucidate individual component-resolved reactivity profiles of venom allergic patients and to provide insights into the role of particular venom components. Due to their allergenic properties, MRJP8 and MRJP9 were designated as isoallergens Api m 11.0101 and Api m 11.0201 respectively.

Second to fourth digit ratio and prostate cancer severity

BACKGROUND

The ratio of the second to the fourth digit (2D:4D ratio) is a sexually dimorphic trait established in utero that differs between ethnic groups. It is associated with prenatal androgen exposure, and studies have evaluated the ratio as a marker for certain traits and disease states known to be associated with higher levels of in utero androgens, such as prostate cancer. There are currently no screening tools that stratify men with prostate cancer according to the severity of their disease. This study aims to investigate the 2D:4D ratio as a potential marker for prostate cancer severity. Our hypothesis was that lower digit ratios, representing higher in utero androgen exposure, would be associated with more severe disease.

METHODS

Measurements were taken of the second and fourth digits of the right hand of male patients diagnosed with prostate cancer. Gleason score, presence of metastasis, family history, age at diagnosis and race were recorded. The distribution of demographic and other patient characteristics were compared with digit ratios to determine relationships.

RESULTS

African-American men with prostate cancer are 3.70 times more likely to have a low 2D:4D digit ratio than Caucasian men with prostate cancer (95% confidence interval: 1.98, 6.92; P < 0.0001). There were no statistically significant differences in the presence of metastasis, Gleason score, family history or age at diagnosis by digit ratio.

CONCLUSION

2D:4D ratio shows strong differences between African-Americans and Caucasians; however, it does not correlate with disease severity in men already diagnosed with prostate cancer. Although this is a small population sample with possible confounding factors, it does not provide evidence to support the hypothesis that prenatal androgens affect prostate cancer grade or progression.

Managing HIV in pregnancy in a community-based sexual health clinic: a decade in review

The management of HIV in pregnancy has evolved significantly over the past 10 years as our experience of combination antiretroviral therapy (ART) has grown. We reviewed 109 pregnancies which were managed at our community-based integrated HIV and sexual health clinic to investigate preconception and antenatal care, and trends in ART over time. We document an increasing proportion of pregnancies in which the mother was aware of her HIV status pre-conception and conception on ART. Pre-conception care was sought in a minority of cases, and many women did not present for first antenatal review until the end of the second trimester. Of 108 live births, there was one case of vertical transmission (0.93%). While our study demonstrates the efficacy of current strategies to prevent mother to child transmission of HIV infection, more could be done to encourage HIV-positive women to seek preconception advice and to attend for early review in the first trimester.

The putative serine protease inhibitor Api m 6 from Apis mellifera venom: recombinant and structural evaluation

BACKGROUND

Immunoglobulin (Ig) E-mediated reactions to honeybee venom can cause severe anaphylaxis, sometimes with fatal consequences. Detailed knowledge of the allergic potential of all venom components is necessary to ensure proper diagnosis and treatment of allergy and to gain a better understanding of the allergological mechanisms of insect venoms.

OBJECTIVE

Our objective was to undertake an immunochemical and structural evaluation of the putative low-molecular-weight serine protease inhibitor Api m 6, a component of honeybee venom.

METHODS

We recombinantly produced Api m 6 as a soluble protein in Escherichia coli and in Spodoptera frugiperda (Sf9) insect cells.We also assessed specific IgE reactivity of venom-sensitized patients with 2 prokaryotically produced Api m 6 variants using enzyme-linked immunosorbent assay. Moreover, we built a structural model ofApi m 6 and compared it with other protease inhibitor structures to gain insights into the function of Api m 6.

RESULTS

In a population of 31 honeybee venom-allergic patients, 26% showed specific IgE reactivity with prokaryotically produced Api m 6, showing it to be a minor but relevant allergen. Molecular modeling of Api m 6 revealed a typical fold of canonical protease inhibitors, supporting the putative function of this venom allergen. Although Api m 6 has a highly variant surface charge, its epitope distribution appears to be similar to that of related proteins.

CONCLUSION

Api m 6 is a honeybee venom component with IgE-sensitizing potential in a fraction of venom-allergic patients. Recombinant Api m 6 can help elucidate individual component-resolved reactivity profiles and increase our understanding of immune responses to low-molecular-weight allergens

Api m 10, a genuine A. mellifera venom allergen, is clinically relevant but underrepresented in therapeutic extracts

BACKGROUND

Generalized systemic reactions to stinging hymenoptera venom constitute a potentially fatal condition in venom-allergic individuals. Hence, the identification and characterization of all allergens is imperative for improvement of diagnosis and design of effective immunotherapeutic approaches. Our aim was the immunochemical characterization of the carbohydrate-rich protein Api m 10, an Apis mellifera venom component and putative allergen, with focus on the relevance of glycosylation. Furthermore, the presence of Api m 10 in honeybee venom (HBV) and licensed venom immunotherapy preparations was addressed.

METHODS

Api m 10 was produced as soluble, aglycosylated protein in Escherichia coli and as differentially glycosylated protein providing a varying degree of fucosylation in insect cells. IgE reactivity and basophil activation of allergic patients were analyzed. For detection of Api m 10 in different venom preparations, a monoclonal human IgE antibody was generated.

RESULTS

Both, the aglycosylated and the glycosylated variant of Api m 10 devoid of cross-reactive carbohydrate determinants (CCD), exhibited IgE reactivity with approximately 50% of HBV-sensitized patients. A corresponding reactivity could be documented for the activation of basophils. Although the detection of the native protein in crude HBV suggested content comparable to other relevant allergens, three therapeutical HBV extracts lacked detectable amounts of this component.

CONCLUSION

Api m 10 is a genuine allergen of A. mellifera venom with IgE sensitizing potential in a significant fraction of allergic patients independent of CCD reactivity. Thus, Api m 10 could become a key element for component-resolved diagnostic tests and improved immunotherapeutic approaches in hymenoptera venom allergy.

Expedited partner therapy for Chlamydia trachomatis at the community pharmacy

OBJECTIVE

Expedited partner treatment (EPT) for uncomplicated Chlamydia trachomatis at the pharmacy is an alternative approach to partner notification that has not yet been evaluated within the UK. The aim of this study was to evaluate EPT for partners using pharmacies in Lothian.

DESIGN

A pilot study over 18 months.

SETTING

Selected healthcare settings and community pharmacies in Lothian, Scotland, UK.

POPULATION

Sexual partners of index cases with uncomplicated C. trachomatis.

METHODS

Index cases with uncomplicated C. trachomatis were given a pharmacy voucher to pass onto sexual partners. Partners could redeem vouchers for free treatment (azithromycin) at one of 90 pharmacies in the area.

MAIN OUTCOME MEASURES

The main outcome measure was the proportion of vouchers redeemed. Secondary outcomes included patient satisfaction, as determined at a telephone follow-up of a subgroup of female index cases from one study site, 1 month later.

RESULTS

In total 577 vouchers were issued to chlamydia-positive index patients of mean age 22.9 years (range 15-47 years). A total of 231 vouchers were redeemed (40%), at a median of 2 days after issue. Only 4% of partners attended a clinic for treatment. Most index patients surveyed reported that partners were satisfied with this method of treatment (48 out of 55; 87%).

CONCLUSIONS

Expedited partner treatment for uncomplicated chlamydia at a pharmacy is a popular choice, and increases options on where, when and how partners are treated.

Cat scratch disease: a diagnostic conundrum

We report the case of a patient who presented to a clinic for evaluation of inguinal lymphadenopathy. Histology of the lymph nodes revealed micoabscess formation suggesting infection with Lymphogranuloma venereum (LGV) or Bartonella henselae--the causative agent in cat scratch disease (CSD). The patient recalled no preceding animal exposure. Clinical and serological findings initially suggested early LGV but convalescent serology supported CSD. This serves as an important reminder that B. henselae infection should be considered a cause of regional lymphadenopathy in individuals suspected of having LGV.

Are national quality standards for traditional Chinese herbal medicine sufficient? Current governmental regulations for traditional Chinese herbal medicine in certain Western countries and China as the Eastern origin country

Traditional Chinese herbal Medicine (TCHM) has been gaining interest and acceptance world wide. TCHM provides on the one side promising perspective of scientific interest and on the other side possible health risks if TCHM drugs are not controlled with respect to quality standards or if practitioners for TCHM are not well trained. This paper outlines an introduction to the scientific aspects and potential risks of TCHM therapy followed by a brief, exploratory overview of the current status of TCHM regulations in certain Western countries like the USA, United Kingdom, Germany, Australia and in China as the Eastern origin country of TCHM. Legal foundations to establish quality and safety standards for TCHM crude drugs and ready-made formulas exist in some countries on a local basis but in practice are poorly enforced, where this products have no drug status. In addition practitioners treating patients with TCHM should be well versed in the pharmacology, side effects, and interactions of these substances with Western medicines and should be certified on a regular basis.

Aloe Vera for Preventing Radiation-induced Skin Reactions: A Systematic Literature Review

AIM

To systematically review and critically appraise the evidence for effectiveness of Aloe vera gel for radiation-induced skin reactions.

MATERIALS AND METHODS

Major biomedical databases and specialist complementary and alternative medicine databases were searched. Additionally, efforts were made to identify unpublished and ongoing research. Relevant research was systematically categorised by study type and appraised according to study design. Clinical commentaries were obtained for each study included in the review.

RESULTS

One earlier systematic review on Aloe vera for a variety of conditions was located. Five published randomised-controlled trials (RCTs) were found, along with two additional RCTs that are not published. No non-RCTs, uncontrolled studies or qualitative studies were found.

CONCLUSIONS

There is no evidence from clinical trials to suggest that topical Aloe vera is effective in preventing or minimising radiation-induced skin reactions in cancer patients. Further methodologically rigorous, sufficiently powered research studies should be conducted to evaluate the effectiveness of currently used and novel therapies for the prevention, minimisation and management of radiation-induced skin reactions.

An oral yohimbine/L-arginine combination (NMI 861) for the treatment of male erectile dysfunction: a pharmacokinetic, pharmacodynamic and interaction study with intravenous nitroglycerine in healthy male subjects

AIMS

Interaction of phosphodiesterase type 5 inhibitors for the treatment of erectile dysfunction with organic nitrates could lead to severe hypotension. NMI 861 is a combination of 7.7 mg yohimbine tartrate and 6 g l-arginine glutamate. A similar oral combination, which contains the same amount of yohimbine and L-arginine, has been shown to improve erectile function in previous studies.

METHODS

In two placebo-controlled, randomized, double-blind, two-way crossover design studies we aimed to assess first the pharmacokinetics and pharmacodynamics of a single oral dose of NMI 861 administered in 16 healthy male subjects, and then the pharmacodynamics of orally administered NMI 861 in combination with intravenous nitroglycerine (GTN) in 12 healthy male subjects. Systolic (SBP) and diastolic (DBP) blood pressures, pulse rate and adverse events were measured in each study.

RESULTS

NMI 861 was well tolerated by all subjects with no significant adverse reactions reported. For L-arginine, mean C(max) +/- SEM (range) was 42 +/- 2.2 (28-63) microg ml(-1) and t(max) (range) was 0.88 (0.50-1.5) h. AUC and t(1/2) were not calculated for L-arginine because of the presence of endogenous concentrations and the contribution from food sources. For yohimbine, mean C(max) was 42 +/- 11 (2.8-128) ng ml(-1); t(max) was 0.57 (0.25-1.0) h; mean AUC(0,8 h) was 65 +/- 24 (5.4-332), ng ml(-1) h and t(1/2) was 1.0 +/- 0.34 (0.40-6.0) h. There was a small but significant difference in the mean change from baseline for SBP from 0 to 6 h after NMI 861 treatment compared with placebo (0.8 +/- 1.4 vs-4.1 +/- 2.1 mmHg, respectively; 95% CI 0.0, 9.8 mmHg (P = 0.047)). There was no significant difference in SBP between treatments for the studied periods 6-12 h and 12-24 h. There was no significant difference in DBP or pulse between NMI 861 and placebo treatments for the three studied time periods. In the study designed to investigate the interaction of organic nitrate with NMI 861, subjects were infused intravenously with increasing doses of GTN (15 min each dose) at 2.5, 5, 10, 20 and 40 microg min(-1) starting 40 min after a single oral dose of either NMI 861 or placebo. There was no significant difference in the hypotensive response induced by GTN between the NMI 861 and placebo treatments. The mean maximum changes from baseline during GTN infusion for subjects administered with either NMI 861 or placebo were a decrease of 16.9 +/- 3.4 vs 13.6 +/- 2.4 mmHg (mean difference between treatments -3.3 mmHg, 95% CI -12.7, 6.0 mmHg (P = 0.460)) for SBP, a decrease of 14.7 +/- 2.0 vs 14.0 +/- 2.0 mmHg for DBP (mean difference -0.7 mmHg, 95% CI -8.2, 6.8 mmHg (P = 0.835)), and an increase of 11.8 +/- 1.9 vs 14.1 +/- 2.4 beats min(-1) for pulse, respectively (mean difference -2.3 beats min(-1), 95% CI -9.3, 4.5 beats min(-1) (P = 0.464)).

CONCLUSIONS

Acute oral administration of NMI 861 was found to be well tolerated and bioavailable in healthy male subjects and no significant hypotensive interaction with intravenous GTN was detected at the doses investigated.

Aerobic and anaerobic ethanol production by Mucor circinelloides during submerged growth

The dimorphic organism Mucor circinelloides is currently being investigated as a potential host for heterologous protein production. The production of ethanol on pentose and hexose sugars was studied in submerged batch cultivations to further the general knowledge of Mucor physiology, with a view to the minimisation or elimination of the by-product ethanol for future process design. Large amounts of ethanol were produced during aerobic growth on glucose under non-oxygen limiting conditions, which is indicative of M. circinelloides being a Crabtree-positive organism. Ethanol production on galactose or xylose was less significant. The response of the organism to increased ethanol concentrations, both as the sole carbon source and in the presence of a sugar, was investigated in terms of biomass formation and morphology.

The effect of CreA in glucose and xylose catabolism in Aspergillus nidulans

The catabolism of glucose and xylose was studied in a wild type and creA deleted (carbon catabolite de-repressed) strain of Aspergillus nidulans. Both strains were cultivated in bioreactors with either glucose or xylose as the sole carbon source, or in the presence of both sugars. In the cultivations on single carbon sources, it was demonstrated that xylose acted as a carbon catabolite repressor (xylose cultivations), while the enzymes in the xylose utilisation pathway were also subject to repression in the presence of glucose (glucose cultivations). In the wild type strain growing on the sugar mixture, glucose repression of xylose utilisation was observed; with xylose utilisation occurring only after glucose was depleted. This phenomenon was not seen in the creA deleted strain, where glucose and xylose were catabolised simultaneously. Measurement of key metabolites and the activities of key enzymes in the xylose utilisation pathway revealed that xylose metabolism was occurring in the creA deleted strain, even at high glucose concentrations. Conversely, in the wild type strain, activities of the key enzymes for xylose metabolism increased only when the effects of glucose repression had been relieved. Xylose was both a repressor and an inducer of xylanases at the same time. The creA mutation seemed to have pleiotropic effects on carbohydratases and carbon catabolism.

Characterization of the Mucor circinelloides life cycle by on-line image analysis

AIMS

The life cycle of the dimorphic fungus Mucor circinelloides was studied in a temperature-controlled flow-through cell, which constitutes an ideal tool when following the development of individual cells, with a view to understanding the growth and differentiation processes occurring in and between the different morphological forms of the organism.

METHODS AND RESULTS

Mycelial growth and the transformation of hyphae into chains of arthrospores were characterized by image analysis techniques and described quantitatively. The influence of the nature (glucose and xylose) and concentration of the carbon source on specific growth rate and hyphal growth unit length were studied. The organism branched more profusely on xylose than on glucose while the specific growth rates determined were rather similar. Methods were developed to study the yeast-like growth phase of M. circinelloides in the flow-through cell, and combined with fluorescent microscopy which allowed new insights to bud formation. Additionally, numbers and distribution of nuclei in arthrospores, hyphae and yeasts were studied.

CONCLUSIONS

The results give essential information on the morphological development of the organism.

SIGNIFICANCE AND IMPACT OF STUDY

Development of any industrial process utilizing this organism will be dependent on the information obtained here for effective process optimization.

Continuous cultivations of a Penicillium chrysogenum strain expressing the expandase gene from Streptomyces clavuligerus: Growth yields and morphological characterization

The growth stoichiometry of a Penicillium chrysogenum strain expressing the expandase gene from Streptomyces clavuligerus was determined in glucose-limited chemostat cultivations using a chemically defined medium. This strain produces adipoyl-7-aminodeacetoxycephalosporanic acid (ad-7-ADCA) when it is fed with adipic acid. The biomass yield and maintenance coefficients for the strain were similar to those found for penicillin-producing strains of Penicillium chrysogenum. The maximum specific growth rate in the chemostat was found to be 0.11 h(-1). Metabolic degradation of adipate was found to take place in significant amounts only at dilution rates below 0.03 h(-1). After three to five residence times, adipate degradation and ad-7-ADCA production disappeared, and this allowed determination of the biomass yield coefficient on adipate. The morphology was measured at different dilution rates and the mean total hyphal length and mean number of tips both increased with an increase in dilution rate from 0.015 to 0.065 h(-1). Both variables decreased when the dilution rate was increased above 0.065 h(-1). A correlation between mean total hyphal length and productivity of ad-7-ADCA was found.

Metabolic control analysis of xylose catabolism in Aspergillus

A kinetic model for xylose catabolism in Aspergillus is proposed. From a thermodynamic analysis it was found that the intermediate xylitol will accumulate during xylose catabolism. Use of the kinetic model allowed metabolic control analysis (MCA) of the xylose catabolic pathway to be carried out, and flux control was shown to be dependent on the metabolite levels. Due to thermodynamic constraints, flux control may reside at the first step in the pathway, i.e., at the xylose reductase, even when the intracellular xylitol concentration is high. On the basis of the kinetic analysis, the general dogma specifying that flux control often resides at the step following an intermediate present at high concentrations was, therefore, shown not to hold. The intracellular xylitol concentration was measured in batch cultivations of two different strains of Aspergillus niger and two different strains of Aspergillus nidulans grown on media containing xylose, and a concentration up to 30 mM was found. Applying MCA showed that the first polyol dehydrogenase (XDH) in the catabolic pathway of xylose exerted the main flux control in the two strains of A. nidulans and A. niger NW324, but the flux control was exerted mainly at the first enzyme of the pathway (XR) of A. niger NW 296.

Growth physiology and dimorphism of Mucor circinelloides (syn. racemosus) during submerged batch cultivation

Mucor circinelloides is being investigated as a possible host for the production of heterologous proteins. Thus, the environmental conditions defining the physiology and morphology of this dimorphic fungus have been investigated in submerged batch cultivation. The optimal conditions for growth of each form have been defined. Pure cultures of the multi-polar budding yeast form could be obtained under anaerobic conditions (with 70% N2/30% CO2 or 100% N2 as the sparge gas and without aeration). The highest maximum specific growth rate (0.30 h(-1)) was obtained in anaerobic cultivation, the yield of biomass on glucose (Y(SX)) was 0.12 (c-mole basis). A high maximum specific growth rate was obtained when the organism grew as the filamentous form under aerobic conditions (0.25 h(-1)), with a Y(SX) of 0.24 (c-mole basis). The maximum specific growth rates achieved are comparable to most industrial filamentous fungi under similar growth conditions. High levels of ethanol were observed with all growth conditions. The overriding effector of morphological development was found to be oxygen. In batch cultures it was therefore possible to induce the dimorphic shift by controlling the influent gas atmosphere. A specific growth rate of 0.19 h(-1) was maintained during the shift from the yeast to the filamentous form.