Microbiota Transplantation as an Adjunct to Standard Periodontal Treatment in Periodontal Disease: A Systematic Review

Periodontitis is a disease linked to severe dysbiosis of the subgingival microbiome. The treatment of periodontitis aims to change the dysbiosis environment to a symbiosis environment. We hypothesized that oral microbiota transplantation can lead to a significant improvement in periodontitis. Therefore, the aim of this study was to determine the effectiveness of microbiota transplantation after standard periodontal treatment in periodontitis patients. The search strategy was carried out by using the Boolean term "AND" to combine the keywords, which were "periodontitis AND microbiota transplantation". Due to the limited resources of the study, we included both in vitro and in vivo investigations in this systematic review. The QUIN risk of bias tool was employed to assess the risk of bias in in vitro studies, while SYRCLE's risk of bias assessment was used for in vivo studies. Oral microbiota transplants (OMTs) have shown potential in treating periodontitis. OMTs significantly reduced periodontitis-associated pathogenic microbial species (P. endodontalis, Prevotella intermedia, T. vincentii, Porphyromonas sp.) and increased beneficial bacteria (P. melaninogenica, Fusobacterium nucleatum, P. catoniae, Capnocytophaga ochracea, C. sputigena, C. gingivalis, Haemophilus parainfluenzae, and Neisseria elongata) upon in vitro testing. Furthermore, in the in vivo tests, single adjunctive OMT also had an effect on the oral microbiota composition compared to the full-mouth mechanical and antimicrobial debridement. OMTs may be cheaper and more effective at addressing high-risk individuals. At present, it is not possible to provide OMT clinical advice due to the lack of available information. This treatment needs to be subjected to more safety and efficacy testing before being included human clinical trials.

Dexmedetomidine target controlled infusion for awake craniotomy†

A 73-year-old woman underwent an awake craniotomy for the resection of a supratentorial brain tumour. We provided sedation for the surgery using a dexmedetomidine target controlled infusion using the Dyck pharmacokinetic model. Using a target controlled infusion allowed more rapid titration to the desired plasma level compared with a manual infusion, without any unexpected cardiovascular, respiratory or other complications. Rapid titration of sedation during awake craniotomy is desirable, allowing deeper sedation during stimulating parts of the surgery, followed by lighter sedation - or absence of sedation - during cortical mapping. While this can be performed manually, we found utilising the Dyck model in this case simple and quick to use, avoiding the need to manually calculate infusion rates. We believe this is the first report of using a target controlled infusion model to administer dexmedetomidine for awake craniotomy, and suggest it could be considered as an alternative to administering a manual infusion.

Single-item principal stress and coping measures: Concurrent and predictive validity and comparisons to teacher measures

The present study analyzed concurrent and predictive validity of single-item scales for assessing principal stress and coping. We examined concurrent and prospective relations among stress and coping single-items with principal job satisfaction, overall health, perceptions of school safety, and principal leadership self-efficacy. We also compared principals and teachers on their stress and coping levels using the same single-item scales. Consistent with the literature on teacher stress and coping, the correlations of principal coping with different outcomes-job satisfaction, overall health, leadership efficacy, and safety perceptions-were stronger in comparison to the correlations between principal stress and those same outcomes. In regression models with both stress and coping, only principal coping predicted concurrent and future principal job satisfaction and overall health, as well as change in those outcomes. Coping also predicted concurrent but not future perceptions of school safety. Stress and coping did not consistently predict concurrent or future measures of leadership self-efficacy. Last, we found that principals reported even higher levels of stress than the well-documented high levels reported by teachers. We discuss areas for further research and potential use of these measures. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Evaluation of prognostic risk models for postoperative pulmonary complications in adult patients undergoing major abdominal surgery: a systematic review and international external validation cohort study

BACKGROUND

Stratifying risk of postoperative pulmonary complications after major abdominal surgery allows clinicians to modify risk through targeted interventions and enhanced monitoring. In this study, we aimed to identify and validate prognostic models against a new consensus definition of postoperative pulmonary complications.

METHODS

We did a systematic review and international external validation cohort study. The systematic review was done in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched MEDLINE and Embase on March 1, 2020, for articles published in English that reported on risk prediction models for postoperative pulmonary complications following abdominal surgery. External validation of existing models was done within a prospective international cohort study of adult patients (≥18 years) undergoing major abdominal surgery. Data were collected between Jan 1, 2019, and April 30, 2019, in the UK, Ireland, and Australia. Discriminative ability and prognostic accuracy summary statistics were compared between models for the 30-day postoperative pulmonary complication rate as defined by the Standardised Endpoints in Perioperative Medicine Core Outcome Measures in Perioperative and Anaesthetic Care (StEP-COMPAC). Model performance was compared using the area under the receiver operating characteristic curve (AUROCC).

FINDINGS

In total, we identified 2903 records from our literature search; of which, 2514 (86·6%) unique records were screened, 121 (4·8%) of 2514 full texts were assessed for eligibility, and 29 unique prognostic models were identified. Nine (31·0%) of 29 models had score development reported only, 19 (65·5%) had undergone internal validation, and only four (13·8%) had been externally validated. Data to validate six eligible models were collected in the international external validation cohort study. Data from 11 591 patients were available, with an overall postoperative pulmonary complication rate of 7·8% (n=903). None of the six models showed good discrimination (defined as AUROCC ≥0·70) for identifying postoperative pulmonary complications, with the Assess Respiratory Risk in Surgical Patients in Catalonia score showing the best discrimination (AUROCC 0·700 [95% CI 0·683-0·717]).

INTERPRETATION

In the pre-COVID-19 pandemic data, variability in the risk of pulmonary complications (StEP-COMPAC definition) following major abdominal surgery was poorly described by existing prognostication tools. To improve surgical safety during the COVID-19 pandemic recovery and beyond, novel risk stratification tools are required.

FUNDING

British Journal of Surgery Society.

Dexmedetomidine as a rescue agent during intracranial neurosurgery in the setting of opioid tolerance

Dexmedetomidine is a versatile sedative agent widely used both in anaesthesia and intensive care. We present the case of a 32-year-old woman with a long-term history of non-prescribed intravenous opioid use who underwent elective resection of a skull base tumour. There was difficulty in achieving an adequate depth of anaesthesia despite the high levels of intravenous and volatile anaesthetic agent. Intra-operatively, a bolus and subsequent infusion of dexmedetomidine helped achieve an adequate depth of anaesthesia. This report highlights some of the benefits of dexmedetomidine for patients who are opioid tolerant, both intra- and postoperatively. It also demonstrates the wide range of beneficial effects dexmedetomidine could have when used as a rescue adjunct in neuroanaesthesia.

Individual and school predictors of teacher stress, coping, and wellness during the COVID-19 pandemic

The Coronavirus disease 2019 (COVID-19) pandemic created unprecedented challenges for the U.S. education system and for teachers. The present study examined correlates and predictors of teacher well-being in the immediate aftermath of school closures related to the pandemic. Data were collected as part of a larger group randomized trial. Six hundred and thirty-nine teachers completed surveys about their stress, coping, health, job satisfaction, and internalizing symptoms in Fall 2019, before the pandemic, and May 2020, during the pandemic. Teachers also provided ratings during COVID-19 of their teaching, student attendance and engagement, and concern about students and families. Teachers reported lower levels of work-related stress after the pandemic's onset compared to their prepandemic levels. Multilevel regression analyses revealed teacher confidence in their ability to manage student behaviors as a consistent and robust predictor of teacher well-being outcomes. Additionally, pre-COVID-19 school-level factors measured in Fall 2019, including collegial school leadership and fair and equitable school discipline structures, also predicted aspects of teacher well-being at the onset of COVID-19. Findings suggest the importance of teacher competence and perceived efficacy in managing student behavior and engaging them in learning to help them adapt to the stressors of a pandemic. Additionally, aspects of organizational health and climate may also help facilitate or hinder teacher adjustment. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

726 Consenting for Surgery During the Pandemic: A Closed-Loop Audit on Discussing and Documenting the Risks of Hospital-Acquired COVID-19

Introduction

There is limited data on the nosocomial transmission of COVID-19. The Royal College of Surgeons (RCS) have published guidance on consenting for surgery, which includes discussing the risks of hospital-acquired COVID-19 with patients as part of the consenting process1. We performed a closed-loop audit on our unit’s consenting practice to assess compliance using the RCS guidelines as the audit standard.

Method

A retrospective case review, including elective and emergency procedures, were identified from June to November 2020. Consent forms were reviewed for evidence of patient counselling for the risks of hospital-acquired COVID-19 using the RCS guidance for comparison. Positive SARS-CoV-2 RT-PCR swabs and radiological imaging suggestive of COVID-19 within 30-days were also assessed.

We undertook the 1st cycle of data collection in September. Following this, we used a local meeting to educate the surgical team. The 2nd cycle (re-audit) was performed in December.

Results

In cycle 1, from June to August 17/29 (59%) case notes documented the discussion of the COVID-19 risk. None of these patients contracted the virus. In cycle 2, from September to November, compliance improved to 28/33 (80%). One (3%) patient had contracted COVID-19. They had a positive SARS-CoV-2 RT-PCR swab and signs suggestive of COVID-19 on their CT chest.

Conclusions

The re-audit demonstrated an improvement in our consenting practice from 59% to 80%. One patient had hospital-acquired COVID-19 during our period of data collection, which reflects current data that suggests nosocomial COVID-19 is rare2. With new advisory guidelines, it is important to discuss these risks.

Exploring the link between principal leadership and family engagement across elementary and middle school

As leaders in the school, principals play an important role in fostering family engagement. Unfortunately, little is known about specific aspects of leadership that promote family engagement. Collegial leadership, an aspect of principal leadership that promotes organizational health via trusting relationships and a sense of community, may be particularly useful to understanding how principals influence family engagement. Drawing on data from two randomized controlled trials evaluating the effects of teacher training in universal classroom management practices, the current study explores the relationship between teacher reports of family engagement and principal collegial leadership. Participants included 3208 students and 207 teachers across 18 elementary and middle schools in the Midwest United States. Utilizing hierarchical linear modeling, results revealed a significant positive relationship between family engagement and overall collegial leadership in addition to specific collegial leadership practices/characteristics. Further, baseline collegial leadership predicted increased end-of-year family engagement when controlling for baseline family engagement, developmental context, intervention status, and student-level characteristics. Overall, results provide empirical evidence for an important link between principal leadership practices and family engagement. Albeit promising, more research is needed to identify and explain the particular mechanisms by which principal collegial leadership may promote family engagement.

Direction Dependence Analysis in the Presence of Confounders: Applications to Linear Mediation Models Using Observational Data

Statistical methods to identify mis-specifications of linear regression models with respect to the direction of dependence (i.e. whether x→y or y→x better approximates the data-generating mechanism) have received considerable attention. Direction dependence analysis (DDA) constitutes such a statistical tool and makes use of higher-moment information of variables to derive statements concerning directional model mis-specifications in observational data. Previous studies on direction of dependence mainly focused on statistical inference and guidelines for the selection from the two directionally competing candidate models (x→y versus y→x) while assuming the absence of unobserved common causes. The present study describes properties of DDA when confounders are present and extends existing DDA methodology by incorporating the confounder model as a possible explanation. We show that all three explanatory models can be uniquely identified under standard DDA assumptions. Further, we discuss the proposed approach in the context of testing competing mediation models and evaluate an organizational model proposing a mediational relation between school leadership and student achievement via school safety using observational data from an urban school district. Overall, DDA provides strong empirical support that school safety has indeed a causal effect on student achievement but suggests that important confounders are present in the school leadership-safety relation.

Sensitivity Analysis and Extensions of Testing the Causal Direction of Dependence: A Rejoinder to Thoemmes (2019)

A commentary by Thoemmes on Wiedermann and Sebastian's introductory article on Direction Dependence Analysis (DDA) is responded to in the interest of elaborating and extending direction dependence principles to evaluate causal effect directionality. Considering Thoemmes' observation that some DDA principles are already well-established in machine learning, we argue that several other connections between DDA and research lines in theoretical statistics, econometrics, and quantitative psychology exist, suggesting that DDA is best conceptualized as a framework that summarizes and extends existing knowledge on properties of linear models under non-normality. Further, Thoemmes articulates concerns about assumptions of error distributions used in our main article and presents an artificial data example in which some DDA tests have suboptimal statistical power. We present extensions of DDA to entirely relax distributional assumptions about errors and describe two sensitivity analysis approaches to critically evaluate DDA results. Both sensitivity approaches are illustrated using Thoemmes' artificial data example. Incorporating DDA sensitivity results yields correct causal conclusions. Thus, overall, we stay with our initial conclusion that the use of higher moments in causal inference constitutes an exciting open research area.

Adverse Drug Reactions in Hospitalized Pediatric Patients: A Prospective Observational Study

OBJECTIVES

To determine the incidence, pattern, causality, preventability, severity and predictors of adverse drug reactions (ADRs) in pediatric population.

METHODS

It was a prospective, observational study that included patients of either sex, of any age treated in the pediatric wards of a tertiary care hospital. Study patients were followed throughout their hospital stay. Whenever an ADR was detected, all the required data was collected and analyzed. Data was analyzed for incidence, causality (by using WHO Probability scale and Naranjo's algorithm), preventability (by using Modified Shumock and Thornton scale), severity (by using Modified Hartwig and Siegel scale) and predictors of ADRs.

RESULTS

Of the 1775 children admitted in the pediatrics ward, 1082 patients met study criteria and were enrolled into the study. A total of 64 ADRs were identified from 54 patients. The incidence of ADRs was 4.99 %. Male patients experienced majority (68.52 %) of ADRs. Drugs most commonly implicated in ADRs were amoxicillin + clavulanate (21.87 %) followed by ceftriaxone (20.31 %). Most (51.56 %) of the ADRs reported belonged to the system organ class, gastrointestinal system disorders. Among the ADRs reported, 82.85 % of ADRs were mild. Majority (87.5 %) of the ADRs were of 'probable' causality category and 96.9 % were not preventable. There was a significant association between occurrence of ADRs and the use of ≥4 number of medications, age (infants) and gender (male).

CONCLUSIONS

Among the pediatric population, infants, male gender and those receiving ≥4 number of medications are at risk of developing ADRs. Constant monitoring is required to address the safety issue in pediatric population especially in infants and patients receiving ≥4 drugs.

Is Radical Bowel Cancer Resection Under Local Anaesthesia and Sedation Feasible?

Some patients with bowel cancer have significant comorbidities, making them unfit for major surgery under general anaesthesia. However, treatment without surgery offers no possibility of cure, and furthermore, symptom control may be poor. We investigated the possibility of performing these resections under local anaesthesia in patients with a slim body habitus in a cohort of patients rejected for general anaesthesia. Eight patients (4 M, 4 F) aged 77-89 were included in this study. All had significant comorbidities and were deemed unfit for general anaesthesia by the consultant anaesthetist in charge of pre assessing high-risk patients. All patients had undergone a thorough assessment, which included P-POSSUM scoring. The recruited patients underwent a careful and fully informed consenting process, leading to standard cancer resections. These resections occurred between 2005 and 2012, under combined local anaesthesia and sedation. The operations undertaken were four right hemicolectomies (for caecal cancer), two Hartmann's procedures (for sigmoid cancer), one Hartmann's procedure with en bloc small bowel resection (for sigmoid cancer invading small bowel) and one transverse colectomy (for mid transverse colon cancer). Seven patients survived radical surgery without complications, although one died from an unrelated cause 8 months after surgery. One of these surviving patients subsequently underwent CABG and further bowel surgery under GA 2 years later for a metachronous sigmoid cancer. There was one postoperative death due to cardiogenic shock on the third postoperative day. Radical cancer resections under local anaesthesia are feasible in suitably selected high-risk patients with acceptable mortality and comparable medium- to long-term results.

A case report on over-replacement of oral calcium supplements causing acute pancreatitis

A 42-year-old female teetotaller presented via the accident and emergency department with a 2-day history of vomiting and upper abdominal pain. She was diagnosed with acute pancreatitis. The aetiology of the pancreatitis was identified as hypercalcaemia secondary to oral calcium supplementation. The hypercalcaemia was corrected by stopping calcium supplements and aggressive fluid resuscitation. A thorough literature search did not show any case reports in which the aetiology of pancreatitis was oral calcium supplement over-replacement.

Mucin lakes or perforation?

We are reporting two cases with similar appearances on post chemo radiotherapy MRI scan of the mucinous adenocarcinoma. There was high signal on T2-weighted sequences of the mucin pools within and beyond the rectal wall. Does this imply that wall tissues become less resistant to cancer pools intrusion after chemo radiation? Does the high intramural pressure have an impact on the protrusion of the cancer pools beyond the muscularis propria?

Final histology reports differ from predicted MRI staging. It highlights the difficulty of the final MRI staging and outcome for mucinous adenocarcinomas. The presence of acellular mesothelial reaction, acellular mucin pools and inflammation extending to the serosal surface causes considerable confusion and may result in over staging or under staging of mucinous adenocarcinoma.

Pathogenesis and prediction of the mucin lakes behaviour prior and post chemoradiotherapy is unclear and requires future study but may impact surgical management.

Cardiac autonomic neuropathy in diabetes mellitus: prevalence, risk factors and utility of corrected QT interval in the ECG for its diagnosis

OBJECTIVES

To study the prevalence and risk factors for cardiac autonomic neuropathy (CAN) and the utility of prolongation of corrected QT interval (QTc) in the ECG to diagnose CAN in patients with diabetes mellitus.

DESIGN AND SETTING

Cross-sectional study conducted among patients attending the diabetic clinic of a teaching hospital.

METHODS

The prevalence of CAN among 100 patients with type 1 and type 2 diabetes mellitus was assessed by the five autonomic function tests by Eving's methodology. The CAN score in each patient and its relationship to the QTc interval were analysed. Possible influences of age, duration of diabetes and coexistent peripheral neuropathy on the occurrence of CAN also were studied.

RESULTS

The prevalence of CAN was 60%. Univariate analysis showed a significant association between CAN and higher age (odds ratio (OR) 15.75), prolongation of QTc (OR 5.55), duration of disease over 10 years (OR 2) and peripheral neuropathy (p<0.001) in patients with type 1 diabetes. Significant risks for CAN among patients with type 2 diabetes were coexistent peripheral neuropathy (OR 14), prolonged QTc (OR 9.75), higher age (OR 7.2) and disease duration over 10 years (OR 1.92) in univariate analysis, but none of them showed independent risk in multivariate analysis. Disease duration over 10 years resulted in QTc prolongation in a significant numbers of cases with type 1 (p<0.001) and type 2 (p = 0.006) diabetes. The sensitivity, specificity and positive predictive value of QTc prolongation for the diagnosis of CAN were 77%, 62.5% and 77% in type 1 and 76.5%, 75% and 81.3% in type 2, respectively. Higher CAN scores correlated with longer QTc intervals (coefficient of correlation 0.73; p<0.001).

CONCLUSIONS

The prevalence of CAN in diabetes mellitus is high. Higher age, longer duration of diabetes and peripheral neuropathy are significant risk factors. QTc interval in the ECG can be used to diagnose CAN with reasonable sensitivity, specificity and positive predictive value.

The prophylaxis of medical patients for thromboembolism pilot study

PURPOSE

We assessed the feasibility of a large randomized trial intended to determine whether low-dose heparin prophylaxis given throughout hospitalization reduces mortality and morbidity in general medical patients.

SUBJECTS AND METHODS

Hospitalized general medical patients aged more than 60 years at 5 Department of Veterans Affairs (VA) medical centers were randomized to receive enoxaparin 40 mg or identical placebo, given daily by subcutaneous injection until hospital discharge. Outcomes included total mortality at 90 days (the primary outcome) and 1 year, and occurrence in the VA hospital within 90 days of symptomatic deep venous thrombosis, pulmonary embolism, and major bleeding.

RESULTS

Only 7.6% of hospitalized patients aged more than 60 years were eligible for the study, although a chart review had predicted 25%. The principal exclusions were prior indication for anticoagulation, anticipated need for anticoagulation, contraindication to heparin, expected hospitalization less than 3 days, and "supportive/palliative care only" status. We randomized 140 patients into each group, 28% of target recruitment. The groups were well matched by age and comorbidities. Death occurred in 13 patients receiving enoxaparin and 14 patients receiving placebo at 90 days (relative risk 0.93, 95% confidence interval 0.26-1.59), and in 36 and 32 patients, respectively, at 1 year (relative risk 1.13, 95% confidence interval 0.66-1.60). Clinical thromboembolic events occurred in 5 patients receiving enoxaparin and 8 patients receiving placebo, and major bleeding occurred in 2 and 5 patients, respectively.

CONCLUSIONS

The pilot study indicated that the full study was not feasible. The decision to use prophylaxis pertains to only a small proportion of general medical patients hospitalized at VA medical centers, and this proportion is overestimated by chart review. The effect of low-dose heparin prophylaxis on clinical outcomes in hospitalized general medical patients remains uncertain.

The use of low-power laser irradiation for faster vascularization of tissue transplants

We studied the effect of low-power laser irradiation on vascularization and take of transplanted rabbit renal and pancreatic tissue in athymic nude mice. The mean size of the transplant and the number of blood vessels in it were higher in irradiated mice compared to nonirradiated controls. Moreover, the organ-specific structure of the transplants was preserved in irradiated mice, but not in the control group. These findings suggest that low-power laser irradiation can be used for promotion of vascularization and take of tissue transplants.

Stimulation of the growth of human tumor by low-power laser irradiation

We studied the effect of low-power laser on the growth of human gastric adenocarcinoma transplanted to athymic mice. Irradiation shortened the latency of tumor growth in recipients from 4-6 months to 21-24 days. After 17 serial passages on athymic mice, the size of tumor node in irradiated recipients on day 33 after transplantation was 161.1 mm(3) (vs. 10.2 mm(3) in nonirradiated mice). These findings suggest that low-power laser irradiation can stimulate the growth of metastases in patients with a history of malignancy.

Transcriptional regulation of the ovine follicle-stimulating hormone-beta gene by activin and gonadotropin-releasing hormone (GnRH): involvement of two proximal activator protein-1 sites for GnRH stimulation

Previous studies from our laboratory demonstrated that a transgene consisting of the promoter for the ovine FSH beta-subunit gene and a luciferase reporter (wt-oFSHbetaLuc) was expressed and regulated like the FSHbeta gene in vivo and in vitro. In the present study pituitary cultures were prepared from these transgenic mice as well as mice carrying mutated oFSHbetaLuc lacking two functional activator protein-1 (AP-1) sites at -120 and -83 bp (mut-oFSHbetaLuc). These AP-1 sites were reported necessary for induction of oFSHbetaLuc by GnRH in a HeLa cell system. To examine the importance of the two AP-1 sites in mediating GnRH and activin effects in primary gonadotropes, pituitary cultures derived from transgenic mice were pretreated with follistatin to remove activin or activin-like factors present in the cultures. Follistatin lowered luciferase expression in cultures carrying both wt-oFSHbetaLuc and mut-oFSHbetaLuc transgenes by 74-86%, and subsequent addition of activin induced luciferase expression of both wt- and mut-transgenes by 4- to 14-fold within 4 h, suggesting that these AP-1 sites are not involved in activin stimulation of FSHbeta gene transcription. When GnRH was added along with activin, the wt-oFSHbetaLuc transgene was induced 200% compared with activin alone, but this effect was not observed with the mut-oFSHbetaLuc transgene. These data confirmed the HeLa cell studies showing that GnRH signals through two AP-1 sites to increase oFSHbeta transcription in gonadotropes. However, as the mutation of both AP-1 sites had no apparent effect on the expression and regulation of the transgene in vivo (basal, castration, GnRH down-regulation, cycle stage, and GnRH immunoneutralization), it appears that these AP-1 sites have little influence over the major effect of GnRH observed in vivo. These data also showed that activin plays a major role in transcriptional regulation of the FSHbeta gene, and the oFSHbeta promoter contains the activin response element(s) that is as yet undefined.

The promoter for the ovine follicle-stimulating hormone-beta gene (FSHbeta) confers FSHbeta-like expression on luciferase in transgenic mice: regulatory studies in vivo and in vitro

Transgenic mice harboring the ovine FSHbeta (oFSHbeta) promoter plus first intron (from -4741 to +759 bp) linked to a luciferase reporter gene (oFSHbetaLuc) were generated to determine whether this promoter can direct tissue-specific expression in vivo and serve as a model for studying hormonal regulation of the FSHbeta gene. Of six lines of transgenic mice analyzed, luciferase was detected uniquely in the pituitaries of five of them. Pituitary luciferase activity was decreased 51-99% by chronic GnRH treatment (Lupron depot). Orchidectomy caused a 2- to 8-fold increase, and ovariectomy caused a 2- to 27-fold increase in pituitary luciferase activity. Furthermore, pituitary luciferase expression was consistently higher on estrus than on diestrus (3- to 20-fold). These data strongly suggested that the transgene was expressed specifically in pituitary gonadotropes and regulated in the same way as the endogenous mouse FSHbeta gene. Using primary pituitary cell cultures prepared from these transgenic mice, basal luciferase expression was maximal on day 3 and then decreased by day 6 of culture, a pattern reflected by endogenous mouse FSH secretion. In these pituitary cultures, basal oFSHbetaLuc expression was decreased 61-82% by follistatin or 59-79% by inhibin. Similarly, mouse FSH secretion was decreased 71% by follistatin or 65% by inhibin. Progesterone inhibited oFSHbetaLuc expression by 44-51%, but it had no effect on endogenous mouse FSH secretion. Estradiol lowered FSH secretion by 21%, but did not decrease oFSHbetaLuc expression significantly. In conclusion, these data demonstrated the ability of the oFSHbeta promoter to direct expression of a reporter gene specifically to pituitary gonadotropes in transgenic mice. Studying oFSHbetaLuc expression in vivo and in cell cultures derived from pituitaries of these transgenic mice should prove useful for understanding many features of FSHbeta regulation.

Vocal cord augmentation with cultured autologous fibroblasts

Bovine collagen is an acceptable agent for vocal cord medialization; however, it produces only a temporary effect. As a foreign protein bovine collagen is susceptible to host collagenase and can induce immune response. Autologous collagen has become recently available, but it is less effective as a medialization agent. The study examines human skin fibroblasts growing in culture. Human skin bioptates were taken from the retroauricular area. Fibroblasts in culture were tested for scar contractility and ability to produce type I collagen (by flow cytometry with labeled antibodies). After five passages in culture the cells produced normal type I collagen, exhibited normal contractility, and did not induce no tumors in nude mice.

Safety of injectable autologous human fibroblasts

Autologous dermal fibroblasts after propagation in cell culture were used for face soft tissue augmentation. Twenty patients aged 37-61 years with facial rhytides and atrophic scars were treated with autologous fibroblasts from cell culture. Significant sustained clinical improvement was observed. Cells of early passages (4, 5, 6) were used for injection. The study showed that cultured fibroblasts were functionally active and produced large quantities of type I collagen. In vitro studies of scar formation potency of injectable fibroblasts showed that these cells possessed normal collagen gel contraction capacity. In vivo experiments showed that cultured fibroblasts exhibited no oncogenic properties and induced no tumors in nude mice.

Estradiol induces and hyperglycosylates the receptor for ovine gonadotropin-releasing hormone

The crucial first link between GnRH and its pleiotropic stimulation of the reproductive system is its receptor (GnRHRec). In mammals, 17beta-estradiol is a major regulator of GnRH action, and part of its regulation occurs at the level of the GnRHRec. In ovine pituitary cultures, estradiol simultaneously increases GnRHRec and GnRH-stimulated LH secretion (the LH response), but after 6-15 h the effect of estradiol becomes paradoxical, and the LH response rapidly decreases to control levels (by 24 h), whereas GnRHRec remains elevated. A preliminary study used photoaffinity labeling of the GnRHRec to show that estradiol can induce 38- and 43-kDa GnRHRec. The photoaffinity technique has been used here to 1) further investigate estradiol-mediated induction of GnRHRec, 2) define the nature of the different sized GnRHRecs, and 3) determine whether the larger size is related to degradation of the LH response. The effect of estradiol is compared with that of inhibin, which only induces the 38-kDa GnRHRec and always increases the LH response to GnRH treatment. Receptors for GnRH in ovine pituitary cultures were photoaffinity labeled with [125I](azidobenzoyl-D-Lys6-des-Gly10)-GnRH-N-ethylamide and analyzed by SDS-PAGE. Treatment with estradiol or inhibin for 6-24 h induced a 38-kDa GnRHRec only. Further treatment with estradiol (>24 h), but not inhibin, shifted the apparent Mr of the GnRHRec to 43 kDa. Phosphatase treatment did not reverse this apparent Mr change. Analysis of receptor glycosylation using N-glycosidase F or tunicamycin showed that the 43-kDa GnRHRec was a hyperglycosylated form of the 38-kDa GnRHRec. The 38-kDa GnRHRec, in turn, was a glycosylated form of the 29-kDa GnRHRec. The studies presented here define several glycosylated intermediates of the ovine GnRHRec that are induced by estradiol and/or inhibin. The function of estrogen-mediated hyperglycosylation is unclear, but kinetic studies dissociate it from degeneration of the LH response to GnRH.

Transcriptional activation of the ovine follicle-stimulating hormone beta-subunit gene by gonadotropin-releasing hormone: involvement of two activating protein-1-binding sites and protein kinase C

FSH is an alpha/beta heterodimeric glycoprotein, the formation of which is regulated primarily by expression of its beta-subunit. Recent studies on transcriptional regulation of the ovine FSH beta-subunit gene (oFSHbeta) have defined two functional activating protein-1 (AP-1) enhancers in the proximal promoter (located at -120 and -83 bp) that are probably physiologically important for FSHbeta expression. As GnRH is a major regulator of FSHbeta expression and is also known to stimulate the synthesis of Jun and Fos family members (AP-1), we investigated the possibility that oFSHbeta transcription may be regulated by GnRH through AP-1. Here we report the use of an in vitro cell system involving transient transfection of GnRH receptors (GnRHR) into HeLa cells to define regulatory elements involved in GnRH-mediated induction of oFSHbeta. This system was used to show that expression of luciferase constructs containing either the -4741/+759 region of the oFSHbeta gene (-4741oFSHbeta-Luc) or the -846/+44 region of the human alpha gene (alpha-Luc; a positive control) was stimulated 3.1 +/- 0.3- and 7.7 +/- 1.9-fold, respectively, by 100 nM GnRH. Another luciferase expression plasmid containing the Rous sarcoma virus promoter (a negative control) showed no response to GnRH. Similar results with these constructs were obtained in COS-7 cells. Studies with progressive 5'-deletion constructs and site-specific mutations demonstrated that this stimulation was dependent on each AP-1 site in the proximal promoter of oFSHbeta. Gel shift assays demonstrated the ability of GnRHR in HeLa cells to increase AP-1 binding activity. Responses in the HeLa cell system were dependent on GnRH (ED50 = 0.5 nM) and GnRHR, which was identified by photoaffinity labeling. In addition, GnRHR-expressing HeLa cells exhibited a normal GnRH-dependent mobilization of intracellular calcium. Finally, as protein kinase C (PKC) is a known target of GnRH action in gonadotropes, the role of PKC in transcriptional regulation of oFSHbeta and alpha-subunit genes by GnRH in HeLa cells was investigated. Although 12-O-tetradecanoyl 13-acetate induction of alpha-Luc and -215oFSHbeta-Luc could be completely blocked in a dose-dependent manner by the specific PKC inhibitor bisindolylmaleimide I, only 57-65% of the GnRH-mediated stimulation of these promoters was blocked, demonstrating the involvement of PKC as well as other signaling systems in GnRH induction. These data define a molecular action of GnRH on oFSHbeta gene transcription that involves two proximal AP-1 enhancer elements and PKC activation. Furthermore, these studies establish the usefulness of HeLa and COS-7 cells to investigate specific aspects of GnRH action on gonadotropin subunit gene expression, as similar signaling pathways and transcription factors that are activated by GnRH in gonadotropes (such as PKC, mitogen-activated protein kinase, Ca2+, and AP-1) exist in these cells.

Activation and function of the epidermal growth factor receptor and erbB-2 during mammary gland morphogenesis

The hormonal stimulation of mammary gland morphogenesis is believed to occur through growth factor receptor signaling pathways. To determine the importance of the epidermal growth factor receptor (EGFR) pathway, we examined extracts of inguinal mammary glands from prepubertal and pubertal mice for tyrosine-phosphorylated EGFR and other erbB receptors. Tyrosine phosphorylation of both EGFR and erbB-2 was detected in normal female BALB/c mice at 5-6 weeks of age, but not during the prepubertal stage, e.g., 24 days of age. Treatment of mice with estradiol or epidermal growth factor also stimulated the formation of mammary EGFR/erbB-2 phosphotyrosine. Waved-2 mice, which have impaired EGFR kinase activity, exhibited less mammary development than did wild-type (wt) mice when both were evaluated at 36 days of age. Because EGFR knockout (KO) mice die shortly after birth, glands from the newborns were implanted under the renal capsules of female nude mice. Under these conditions, extensive ductal growth was observed in mammary glands from wt animals; in contrast, glands from EGFR KO mice failed to grow beyond rudimentary structures. Tissue recombinants revealed that the wt fat pad supported the morphogenesis of EGFR KO epithelium, whereas the EGFR KO fat pad did not. Taken together, these data suggest that EGFR is essential for morphogenesis of the mammary ducts and functions during this period of mammary development as a heterodimer with erbB-2 in the mammary stroma.

Insulin-like growth factor-1 (IGF-1) receptor-insulin receptor substrate complexes in the uterus. Altered signaling response to estradiol in the IGF-1(m/m) mouse

Some of the actions of estradiol occur through stimulation of growth factor pathways in target organs. Tyrosine-phosphorylated (Tyr(P)) insulin-like growth factor-1 receptor (IGF-1R) and the insulin receptor substrate (IRS)-1 are found in the uterus of mice treated with estradiol. Immunoprecipitates of uterine Tyr(P) IRS-1 contained both p85, the regulatory subunit of phosphatidylinositol (PI) 3-kinase, and PI 3-kinase catalytic activity. Estradiol also stimulated binding of IRS-1 and PI 3-kinase to the IGF-1R. Depletion of IRS-1 from uterine extracts reduced PI 3-kinase associated with the receptor, which suggests that binding of the enzyme to IGF-1R occurs primarily in a complex that also contains IRS-1. Following treatment with estradiol, formation of Tyr(P) IGF-1R, Tyr(P) IRS-1, and the p85.IRS-1 complex was very weak in the uterus of IGF-1(m/m) mice, which are severely deficient in IGF-1. This indicated that most, if not all, of the estradiol-stimulated Tyr phosphorylation of uterine IRS-1 originates from ligand activation of IGF-1R kinase. IRS-2 was also Tyr-phosphorylated in the normal uterus and bound more IGF-1R and p85 in response to estradiol; however, a marked decrease in levels of uterine IRS-2 occurred 12-24 h after treatment with estradiol. Since IRS-2 was present in IGF-1R precipitates and a recombinant form of IGF-1 (long R3 IGF-1) stimulated formation of Tyr(P) IRS-2, hormonal activation of this docking protein probably occurs through the IGF-1R. In summary, our findings show that estrogen activation of uterine IGF-1R kinase results in enhanced binding of p85 (PI 3-kinase) to IRS-1 and IRS-2. The formation of one or both of these complexes may be important for the potent mitogenic action of this steroid. That estradiol stimulated a decrease of IRS-2, but not of IRS-1, suggests that these docking proteins have different roles in hormone-induced signaling in the uterus.

DNA polymerase epsilon encoded by cdc20+ is required for chromosomal DNA replication in the fission yeast Schizosaccharomyces pombe

BACKGROUND

DNA polymerase II (PolII), the homologue of mammalian DNA polymerase epsilon, is essential for chromosomal DNA replication in the budding yeast Saccharomyces cerevisiae and also participates in S-phase checkpoint control. An important issue is whether chromosomal DNA replication in other eukaryotes, including the fission yeast Schizosaccharomyces pombe--in which the characteristics of replication origins are poorly defined--also requires DNA polymerase epsilon. It has been shown that DNA polymerase epsilon is not required for the in vitro replication of SV40 DNA by human cell extracts.

RESULTS

We have cloned and sequenced S. pombe pol2+, which is identical to the cell-cycle gene cdc20+, encoding the catalytic polypeptide of DNA polymerase epsilon (Pol epsilon). The predicted amino acid sequence of Pol epsilon is highly homologous to that of S. cerevisiae PolII and human Pol epsilon. Consistent with this, the Pol epsilon polypeptide was recognized by polyclonal antibodies against S. cerevisiae PolII holoenzyme (PolII*). The terminal morphology of cells containing the disrupted pol2 gene was similar to that of DNA replication mutant cells and cdc20 mutant cells. Furthermore, the Pol epsilon activity from temperature-sensitive S. pombe cdc20 mutant cells was temperature-sensitive, and chromosomal DNA replication in the mutant cells was inhibited at the restrictive temperatures.

CONCLUSION

These data strongly suggest that Pol epsilon is required for normal chromosomal DNA replication in S. pombe, as is PolII in S. cerevisiae. Thus, eukaryotic chromosomal DNA is replicated differently from that of viral SV40 DNA.

Oophoropexy to prevent sequential or recurrent torsion

Laparoscopic oophoropexy may prevent recurrent (repeat torsion of the same ovary) or sequential (subsequent torsion of the contralateral ovary) ovarian torsion. Two adolescent girls with sequential ovarian torsion underwent laparoscopic plication of utero-ovarian ligaments. Neither patient has had recurrence in the 6. 5 and 2 years, respectively, since surgery. Sequential ovarian torsion has been described,1-8 and in almost every instance the authors raised the question of whether or not oophoropexy should have been done at the time of the initial episode of torsion. In virtually every instance the second ovary was removed and the patient rendered menopausal. In two patients with sequential ovarian torsion the ovary was saved and oophoropexy performed laparoscopically in an effort to prevent recurrence.

EGF-related peptides and their receptors in mammary gland development

The discovery of multiple EGF-like ligands and erbB receptors offers the potential for a highly diverse signaling system allowing specific ligand/receptor complexes to be created in response to a certain hormone(s) or stage of mammary development. The known erbB receptors and several of the erbB-related ligands are synthesized by the normal mammary gland and have different temporal and spatial expression patterns. For instance, cumulative findings support the concepts that the EGF receptor has an essential role in morphogenesis of the mammary gland and that activation of this receptor occurs in response to estradiol-stimulated synthesis of an EGF receptor ligand in mammary stromal cells. The importance of both epithelial and stromal mammary cells in the hormonal activation of erbB-related pathways is underscored in this review. Current experimental protocols that utilize erbB mutant mice or enable detection of phosphorylated erbB members and their proximal substrates should permit more precise identification of the pathways operative in the mammary gland.

Estradiol stimulates tyrosine phosphorylation of the insulin-like growth factor-1 receptor and insulin receptor substrate-1 in the uterus

The signaling pathways associated with estrogen-induced proliferation of epithelial cells in the reproductive tract have not been defined. To identify receptor tyrosine kinases that are activated in vivo by 17 beta-estradiol (E2), uteri from ovariectomized mice were examined for enhanced tyrosine phosphorylation of various receptors and a receptor substrate following treatment with this hormone. Within 4 hr after hormone exposure, extracts showed increased phosphotyrosine (P-Tyr) immunoreactivity at several bands, including 170- and 180-kDa; these bands were still apparent at 24 hr after E2. Analysis of immunoprecipitates from uterine extracts revealed that E2 enhanced tyrosine phosphorylation of the insulin-like growth factor-1 receptor (IGF-1R) and insulin receptor substrate-1 (IRS-1) by 6 hr. Comparison of supernatants from IRS-1 and control rabbit IgG immunoprecipitates indicated that the 170-kDa P-Tyr band in extracts was equivalent to IRS-1. The receptors for epidermal growth factor, platelet-derived growth factor, and basic fibroblast growth factor did not exhibit an E2-induced increase in P-Tyr content. The nonestrogenic steroid hormones examined did not stimulate the P-Tyr content of IGF-1R or IRS-1. Immunolocalization of P-Tyr and IRS-1 revealed strong reactivity in the epithelial layer of the uterus from E2-treated mice, suggesting that the majority of P-Tyr bands observed in immunoblots originate in the epithelium. Since hormonal activation of IRS-1 is epithelial, estrogen-specific, and initiated before maximal DNA synthesis occurs following treatment with hormone, this protein, as part of the IGF-1R pathway, may be important in mediating estrogen-stimulated proliferation in the uterus.