ADAD1 is required for normal translation of nuclear pore and transport protein transcripts in spermatids of Mus musculus†

ADAD1 is a testis-specific RNA-binding protein expressed in post-meiotic spermatids whose loss leads to defective sperm and male infertility. However, the drivers of the Adad1 phenotype remain unclear. Morphological and functional analysis of Adad1 mutant sperm showed defective DNA compaction, abnormal head shaping, and reduced motility. Mutant testes demonstrated minimal transcriptome changes; however, ribosome association of many transcripts was reduced, suggesting ADAD1 may be required for their translational activation. Further, immunofluorescence of proteins encoded by select transcripts showed delayed protein accumulation. Additional analyses demonstrated impaired subcellular localization of multiple proteins, suggesting protein transport is also abnormal in Adad1 mutants. To clarify the mechanism giving rise to this, the manchette, a protein transport microtubule network, and the LINC (linker of nucleoskeleton and cytoskeleton) complex, which connects the manchette to the nuclear lamin, were assessed across spermatid development. Proteins of both displayed delayed translation and/or localization in mutant spermatids implicating ADAD1 in their regulation, even in the absence of altered ribosome association. Finally, ADAD1's impact on the NPC (nuclear pore complex), a regulator of both the manchette and the LINC complex, was examined. Reduced ribosome association of NPC encoding transcripts and reduced NPC protein abundance along with abnormal localization in Adad1 mutants confirmed ADAD1's impact on translation is required for a NPC in post-meiotic germ cells. Together, these studies lead to a model whereby ADAD1's influence on nuclear transport leads to deregulation of the LINC complex and the manchette, ultimately generating the range of physiological defects observed in the Adad1 phenotype.

The Effects of Source Cues and Issue Frames During COVID-19

The health and economic outcomes of the COVID-19 pandemic will in part be determined by how effectively experts can communicate information to the public and the degree to which people follow expert recommendation. Using a survey experiment conducted in May 2020 with almost 5,000 respondents, this paper examines the effect of source cues and message frames on perceptions of information credibility in the context of COVID-19. Each health recommendation was framed by expert or nonexpert sources, was fact- or experience-based, and suggested potential gain or loss to test if either the source cue or framing of issues affected responses to the pandemic. We find no evidence that either source cue or message framing influence people’s responses – instead, respondents’ ideological predispositions, media consumption, and age explain much of the variation in survey responses, suggesting that public health messaging may face challenges from growing ideological cleavages in American politics.

Lessons from Fukushima: Potassium Iodide After a Nuclear Disaster

ABSTRACT

The release of radioactive iodine after a nuclear disaster, such as those that occurred at the Fukushima Daiichi Nuclear Power Plant in Japan 10 years ago and Three Mile Island in Pennsylvania in 1979, increases thyroid cancer risk among people who are exposed. Certain populations are especially vulnerable, including pregnant and breastfeeding women, children, and neonates. Potassium iodide (KI) can effectively block radioactive iodine from being absorbed by the thyroid gland if taken immediately after a radiation release. This article examines lessons learned from Fukushima to enhance disaster readiness and nursing actions. Nurses should be directly involved in vulnerability assessments, emergency planning, and in ensuring the availability, accessibility, and distribution of KI within U.S. nuclear power plant emergency planning zones before a crisis occurs.

Intraoperative Sepsis: A Simulation Case for Anesthesiology Residents

INTRODUCTION

Sepsis is a major cause of morbidity and mortality in medicine and is managed in ICUs daily. Critical care training is a vital part of anesthesiology residency, and understanding the presentation, management, and treatment of septic shock is fundamental to intraoperative patient care.

METHODS

This simulation involved a 58-year-old man undergoing surgical debridement of a peripancreatic cyst with hemodynamic instability and septic shock. We conducted the simulation yearly for clinical anesthesia year 2 residents (n = 26) in 1-hour sessions with three to five learners at a time. The simulation covered the six Anesthesiology Milestones related to sepsis and septic shock as outlined in the Anesthesiology Milestones Project.

RESULTS

To date, 155 anesthesiology residents have completed the simulation. Commonly missed critical actions included failure to recognize the need for invasive lines, provide appropriate volumes of fluid resuscitation, inquire about blood cultures and antibiotics, and recognize the need for the patient to remain intubated. Most participants could appropriately diagnose and treat intraoperative septic shock, but all had moments of action or inaction to discuss and improve upon, and all learned from this scenario.

DISCUSSION

Simulation is an optimal way to practice the more rare and life-threatening clinical events in medicine. Even though septic shock is commonly managed in the ICU, it is relatively uncommon for it to develop acutely in the OR. This simulation is an effective and educational way to discuss the most recent sepsis/septic shock definition and review evidence-based guidelines for treatment.

Comparing Physical Examination With Sonographic Versions of the Same Examination Techniques for Splenomegaly

OBJECTIVES

To determine whether sonographic versions of physical examination techniques can accurately identify splenomegaly, Castell's method (Ann Intern Med 1967; 67:1265-1267), the sonographic Castell's method, spleen tip palpation, and the sonographic spleen tip technique were compared with reference measurements.

METHODS

Two clinicians trained in bedside sonography patients recruited from an urban hematology clinic. Each patient was examined for splenomegaly using conventional percussion and palpation techniques (Castell's method and spleen tip palpation, respectively), as well as the sonographic versions of these maneuvers (sonographic Castell's method and sonographic spleen tip technique). Results were compared with a reference standard based on professional sonographer measurements.

RESULTS

The sonographic Castell's method had greater sensitivity (91.7% [95% confidence interval, 61.5% to 99.8%]) than the traditional Castell's method (83.3% [95% confidence interval, 51.6% to 97.9%]) but took longer to perform [mean ± SD, 28.8 ± 18.6 versus 18.8 ± 8.1 seconds; P = .01). Palpable and positive sonographic spleen tip results were both 100% specific, but the sonographic spleen tip method was more sensitive (58.3% [95% confidence interval, 27.7% to 84.8%] versus 33.3% [95% confidence interval, 9.9% to 65.1%]).

CONCLUSIONS

Sonographic versions of traditional physical examination maneuvers have greater diagnostic accuracy than the physical examination maneuvers from which they are derived but may take longer to perform. We recommend a combination of traditional physical examination and sonographic techniques when evaluating for splenomegaly at the bedside.

Traumatic brain injury, dry eye and comorbid pain diagnoses in US veterans

AIMS

The purpose of the study is to evaluate the relationship between dry eye (DE) and pain diagnoses in US veterans with and without traumatic brain injury (TBI).

METHODS

Retrospective cohort study of veterans who were seen in the Veterans Administration Hospital (VA) between 1 January 2010 and 31 December 2014. Veterans were separated into two groups by the presence or absence of an International Classification of Diseases, Ninth Revision diagnosis of TBI and assessed for DE and other comorbidities. A dendrogram was used to investigate the linkage between TBI, DE, chronic pain and other comorbid conditions.

RESULTS

Of the 3 265 894 veterans seen during the 5-year period, 3.97% carried a diagnosis of TBI. Veterans with TBI were more likely to have a diagnosis of DE compared with their counterparts without TBI (37.2% vs 29.1%, p<0.0005). The association was stronger between TBI and ocular pain (OR 3.08; 95% CI 3.03 to 3.13) compared with tear film dysfunction (OR 1.09; 95% CI 1.07 to 1.10). Those with TBI were also about twice as likely to have a diagnosis of chronic pain, headache, depression or post-traumatic stress disorder compared with their counterparts without TBI. Cluster analysis of TBI, DE and pain diagnoses of interest revealed that central pain syndrome, cluster headache, sicca syndrome, keratoconjunctivitis sicca and late effect of injury to the nervous system (as can be seen after TBI) were all closely clustered together.

CONCLUSIONS

DE and pain disorders occur at higher frequencies in patients with a diagnosis of TBI, suggesting a common underlying pathophysiology.

Accuracy of Spleen Measurement by Medical Residents Using Hand-Carried Ultrasound

OBJECTIVES

Easily palpable splenomegaly can be identified on physical examination, but it is difficult to detect lesser degrees of splenomegaly. Rapid bedside assessment can be conducted with hand-carried ultrasound. We performed this study to determine whether medical residents could reliably assess spleen size using hand-carried ultrasound after a brief educational intervention.

METHODS

Postgraduate year 1 internal medicine residents were shown a brief (45-minute) presentation on ultrasound basics, the use of hand-carried ultrasound, and principles of splenic ultrasound imaging. They practiced on each other, using hand-carried ultrasound to assess spleen size, for 1 hour in the presence of an instructor. Patients with varying degrees of splenomegaly and hospital staff were recruited at Vancouver General Hospital. A sonographer measured spleen size in each participant using conventional ultrasound. Subsequently, the trained residents scanned the participants using hand-carried ultrasound, blinded to the sonographer's measurements and the participants' diagnoses. The instructor was not present during scanning.

RESULTS

Twelve first-year residents (8 male and 4 female; mean age ± SEM, 28 ± 1 years; all with limited prior ultrasound training) and 19 patients and staff members (10 male and 9 female; mean age, 60 ± 4 years; body mass index, 24 ± 2 kg/m(2)) were recruited. The greatest longitudinal measurements were 14.0 ± 0.7 cm with conventional ultrasound administered by the sonographer and 13.2 ± 0.9 cm with hand-carried ultrasound administered by the residents (P > .05, not significant). The correlation between conventional and hand-carried ultrasound was r = 0.81 (P < .001).

CONCLUSIONS

Internal medicine residents can reliably assess spleen size at the point of care using hand-carried ultrasound with minimal training. Our findings, if replicated in other centers and in different clinical scenarios, may change the way that clinicians examine the spleen.

Implications of the Fukushima Nuclear Disaster: Man-Made Hazards, Vulnerability Factors, and Risk to Environmental Health

The objective of this article was to examine the environmental health implications of the 2011 Fukushima nuclear disaster from an all-hazards perspective. The authors performed a literature review that included Japanese and international nuclear guidance and policy, scientific papers, and reports on the Chernobyl and Three Mile Island disasters while also considering all-hazards preparedness rubrics in the U.S. The examination of the literature resulted in the following: a) the authors' "All-Hazards Planning Reference Model" that distinguishes three planning categories-Disaster Trigger Event, Man-Made Hazards, and Vulnerability Factors; b) the generalization of their model to other countries; and c) advocacy for environmental health end fate to be considered in planning phases to minimize risk to environmental health. This article discusses inconsistencies in disaster planning and nomenclature existing in the studied materials and international guidance and proposes new opportunity for developing predisaster risk assessment, risk communication, and prevention capacity building.

Prevalence, Knowledge, and Concern About Bed Bugs

Recent research suggests that the resurgence of bed bugs in the U.S. has occurred at an alarming rate. Assumptions have been made that socioeconomic status is not associated with the prevalence of bed bug infestations. Little information is available at the local level, however, about the prevalence of bed bugs in private homes. The authors' pilot study aimed to identify prevalence, knowledge, and concern about bed bugs in one higher income village in Ohio utilizing survey methodology. Responses from 96 individuals who completed the Prevalence, Knowledge, and Concern About Bed Bugs survey were utilized for analysis. The majority of the sample respondents were white and 95% reported that they owned their residence. Only 6% knew someone with bed bugs. Additionally, 52% reported they were somewhat concerned about bed bugs. About 46% reported that they had changed their behavior. For a higher income area, the prevalence was dissimilar to the rate reported in the general public (about 20%). This suggests that bed bugs may be an environmental issue effecting low-income populations disproportionately. Further research is needed in areas of differing socioeconomic levels.

Multiparametric magnetic resonance imaging-targeted biopsy for the detection of prostate cancer in patients with prior negative biopsy results

PURPOSE

We aimed to determine the performance of multiparametric magnetic resonance imaging (mpMRI) in the detection of prostate cancer (PCa) in patients with prior negative transrectal ultrasound-guided prostate biopsy (TRUS-B) results.

MATERIALS AND METHODS

Between 2010 and 2013, 2,416 men underwent TRUS-B or an mpMRI or both at Vancouver General Hospital. Among these, 283 men had persistent suspicion of PCa despite prior negative TRUS-B finding. An MRI was obtained in 112, and a lesion (prostate imaging reporting and data system score ≥ 3) was identified in 88 cases (78%). A subsequent combined MRI-targeted and standard template biopsy was performed in 86 cases. A matching cohort of 86 patients was selected using a one-nearest neighbor method without replacement. The end points were the rate of diagnosis of PCa and significant PCa (sPCa) (Gleason > 6, or > 2 cores, or > 50% of any core).

RESULTS

MRI-targeted TRUS-B detected PCa and sPCa in 36 (41.9%) and 30 (34.9%) men when compared with 19 (22.1%) and 14 (16.3%), respectively, men without mpMRI (P = 0.005 for both). In 9 cases (10.4%), MRI-targeted TRUS-B detected sPCa that was missed on standard cores. sPCa was present in 6 cases (6.9%) on standard cores but not the targeted cores. Multivariate analysis revealed that prostate imaging reporting and data system score and prostate-specific antigen density > 0.15 ng/ml(2) were statistically significant predictors of significant cancer detection (odds ratio = 14.93, P < 0.001 and odds ratio = 6.19, P = 0.02, respectively).

CONCLUSION

In patients with prior negative TRUS-B finding, MRI-targeted TRUS-B improves the detection rate of all PCa and sPCa.

Environmental health--champions of One Health

The authors find overwhelming evidence among environmental health practitioners that One Health disease reporting concepts are essential to the early detection of, and expedient recovery from, pandemic disease events. The authors also find, however, extraordinary evidence that local public health is not prepared, and potentially unaware of their responsibility, to be the initiator of the zoonotic infectious disease information intelligence necessary to make such early event mitigation possible. The authors propose that NEHA take an affirmative step towards the development of local public health-initiated biosurveillance systems by organizing and leading a tabletop study group that includes the Centers for Disease Control and Prevention, American Veterinary Medical Association, American Medical Association, Food and Drug Administration, U.S. Department of Agriculture, Institute of Medicine, and a robust panel of NEHA state affiliates. This study group should discuss the infrastructure necessary for local public health-the frontline against community-acquired infectious disease-to be the initiators of environmental health, veterinary, and medical One Health biosurveillance systems. The need to establish a community-focused, integrated disease prevention strategy that cautions people about the risks associated with food, water, animal, and contaminated environmental media, both prior to and during epidemic and pandemic events is equally important.

Bed bugs, public health, and social justice: Part 2, An opinion survey

Bed bug infestations have resurged globally, nationally, and locally, yet the public health community in the U.S. has yet to mount a coordinated response to the escalating bed bug problem. Surveys of attendees at the 2009 National Environmental Health Association Annual Educational Conference & Exhibition, 2009 Ohio Association of Health Commissioners Fall Conference, 2009 Central Ohio Bed Bug Summit, and 2010 Hamilton County Council on Aging Annual Conference were conducted to gauge opinions about bed bugs. Survey results revealed that 90% of all respondents considered bed bugs to be a public health concern, and 73% indicated that bed bugs pose an environmental justice concern. These findings, which indicate that bed bugs are an inescapable public health mandate with environmental justice undertones, should rally public health agencies at federal, state, and local levels to respond with authority of agency to the escalating bed bug problem.

Bed bugs, public health, and social justice: Part 1, A call to action

The resurgence of bed bugs poses an urgent situation since infestations are rampant globally, nationally, and locally. In Ohio, bed bugs have become a virtual epidemic in many towns and cities, especially in central and southwestern regions of the state. These blood-feeding insects cause an array of adverse health effects in humans. Furthermore, bed bugs disproportionately occur in urban areas, and housing and the built environment are now recognized as dominant influences on health. Bed bugs' potential role in disease transmission remains unqualified to date, and research on this issue is urgently needed. The escalating global bed bug resurgence leaves the divided public health community in a precarious social justice position if the lack of response to bed bug infestations disproportionately impacts underserved populations. Bed bugs are an urgent public health and environmental justice concern, and the authors recommend that public health agencies respond with authority of agency.

251 DEVELOPMENT OF A TECHNIQUE FOR STAINING CHROMOSOME AND SPINDLE OF MI AND MII BABOON OOCYTES

The objective of this study was to develop a technique for staining baboon oocytes in order to detect chromosome and spindle disorganizations in abnormal oocytes. Baboon oocytes were retrieved by laparoscopy at Southwest National Primate Center/San Antonio following ovulation induction. The metaphase-I (MI) and metaphase-II (MII) oocytes were placed in one-mL sterile plastic tubes containing 10% formaldehyde solution. The tubes were sent by regular mail from San Antonio to the Reproductive Sciences Laboratory at Texas A&M University/College Station. The duration of oocyte fixation was from two to three weeks. The technique of baboon oocyte staining was based on the modification of the mouse oocyte staining protocol. A total of nine oocytes were collected for staining. The age of the baboon was six years. The oocytes were washed four times each, 20–30 min at room temperature, with PBS containing 10 µL Triton, 0.2 g dry milk, 2 g bovine serum albumin, and 0.75 g of glycine. The oocytes were kept over night in a refrigerator. The oocytes were stained with primary antibody solution (Monoclonal Anti Beta-Tubulin, Sigma Co., St. Louis, MO, USA) for 60 min at 37�C. After staining, five washes were performed for 20–30 min each at room temperature (RT). The oocytes were stained with secondary antibody solution (Alexa fluor 488, Invitrogen Co., Carlsbad, CA, USA) for 60 min at 37�C. Three washes were carried out at the end of the second staining, 20–30 min each at RT. Final staining was performed with Vectashieldreg propidium iodide (PI; Vector Laboratories, Burlingame, CA, USA) on a barrier slide which was then covered with a cover slide. Each slide contained 2–3 stained oocytes. The barrier slides were kept in a refrigerator for at least 48–72 h before imaging the oocytes. Chromosomes were stained with PI (red) and micro-tubular spindles were stained with anti Beta-tubulin antibodies + Alexa 488 (green). Cumulus cells appeared as bright red dots. The chromosomes of the immature oocytes (MI) did not yet appear completely aligned at the metaphase plate. The mature oocytes (MII) had extruded the polar body and it was clearly visible. The chromosomes looked elegantly organized at the metaphase plate. One chromosome was found to be disorganized (not aligned at the methaphase plate) in some oocytes which may be due to the side effect of superovulation treatment, but the spindles looked organized. In conclusion, the technique is found to be suitable for study of chromosome and spindle disorganizations which may cause recurrent abortions, birth defects, and infertility in nonhuman and human primates.

Alteration of the menstrual cycle in baboons placed on tethering devices and moved to individual housing--a stress model for a follicular phase defect

BACKGROUND

During an attempt to identify endocrine characteristics in the baboon that would more precisely predict ovulatory status for assisted reproductive techniques, we observed severe alterations in the menstrual cycle length upon introducing an environmental stress. This environmental stress involved moving animals from their baseline gang cage environment to individual indoor caging and placing them on a tethering apparatus.

METHODS

Five adult female baboons were followed for changes in sex skin indicative of menstrual cycle timing and move from outdoor gang gages to individual indoor cages during the early follicular phase of their cycle. A tether device including a surgically implanted cannula was then installed to facilitate daily blood draws without sedation. Radioimmuonoassays were performed to monitor serum estradiol levels and lapraroscopic surveillance was used to confirm time of ovulation.

RESULTS

Complete data sets were collected from four of the female baboons. In each case, a prolongation of the menstrual cycle was noted either during the cycle during which the females were moved to indoor caging or during the cycle immediately following the move. This prolongation was isolated to the follicular phase of the affected cycle.

CONCLUSIONS

We conclude that otherwise normal handling procedures, including movement to new caging, and/or installation of a tether device, can impart a stress effect on reproductively cycling adult female baboons, such that folliculogenesis is delayed.

Functional variants of antioxidant genes in smokers with COPD and in those with normal lung function

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is predominantly the consequence of chronic smoking exposure, but its development may be influenced by genetic variants that affect lung remodelling, inflammation, and defence from oxidant stress. A study was undertaken to determine whether genetic variants within genes encoding the antioxidant enzymes superoxide dismutase (SOD) and catalase may be associated with the development of impaired lung function.

METHODS

In a case-control study, the allele and genotype frequencies of functional polymorphisms from SOD1 (CuZnSOD), SOD2 (MnSOD), SOD3 (extracellular SOD), and catalase (CAT) were compared in chronic smokers with normal lung function (resistant smokers) and in those with COPD.

RESULTS

Significantly higher frequencies of the G allele and CG/GG genotype of the 213 SOD3 polymorphism were found in resistant smokers (odds ratios (ORs) 4.3 (95% CI 1.5 to 13.3) and 4.2, 95% CI 1.4 to 13.3), Bonferroni corrected p = 0.02 and p = 0.02, respectively) than in those with COPD. There were no differences between the COPD and resistant smokers for the SOD1, SOD2, or CAT polymorphisms tested.

CONCLUSIONS

The 213Gly variant of the SOD3 gene may, through antioxidant or anti-inflammatory effects, confer a degree of resistance in some smokers to the development of COPD.

Deletion and reduced expression of the Fanconi anemia FANCA gene in sporadic acute myeloid leukemia

Fanconi anemia (FA) is an autosomal recessive chromosomal instability disorder caused by mutations in one of seven known genes (FANCA,C,D2,E,F,G and BRCA2). Mutations in the FANCA gene are the most prevalent, accounting for two-thirds of FA cases. Affected individuals have greatly increased risks of acute myeloid leukemia (AML). This raises the question as to whether inherited or acquired mutations in FA genes might be involved in the development of sporadic AML. Quantitative fluorescent PCR was used to screen archival DNA from sporadic AML cases for FANCA deletions, which account for 40% of FANCA mutations in FA homozygotes. Four heterozygous deletions were found in 101 samples screened, which is 35-fold higher than the expected population frequency for germline FANCA deletions (P<0.0001). Sequencing FANCA in the AML samples with FANCA deletions did not detect mutations in the second allele and there was no evidence of epigenetic silencing by hypermethylation. However, real-time quantitative PCR analysis in these samples showed reduced expression of FANCA compared to nondeleted AML samples and to controls. These findings suggest that gene deletions and reduced expression of FANCA may be involved in the promotion of genetic instability in a subset of cases of sporadic AML.

A methodologic issue for ophthalmic telemedicine: image quality and its effect on diagnostic accuracy and confidence

BACKGROUND

The possibility of ophthalmic telemedicine raises questions as to the quality of images displayed on a video display terminal and its effect on a doctor's accuracy and confidence of diagnosis. This study compares diagnostic accuracy and confidence levels of subjects observing two formats of retinal imaging.

METHODS

Test images included 90 conventional 4- x 6-inch retinal fundus photographs and the same set of photographs after they had been scanned, digitized, modified in brightness and contrast, and displayed on a video display terminal. Fifty-six of the images demonstrated one or more retinal anomalies; the remaining 34 were of normal fundi. Abnormalities were selected on the basis of estimates of prevalence in the general population. Twenty optometrists affiliated with the Southern California College of Optometry participated as subjects. One group of 10 was shown the photographs; the remaining ten subjects were shown the digitized images. Both groups were asked if the pictures were "healthy" or "unhealthy," how confident they were of their decision, and, if abnormal, what was the ocular disease.

RESULT

T-tests were used to compare the results of the two groups. There was a statistically significant difference in the confidence of a specific diagnosis between the two groups (p = 0.018), as well as tendencies toward significance on other measures.

CONCLUSION

Viewing digitally reconstructed photographic images of the retina on a video display caused doctors to lose confidence in making a diagnosis before they lost accuracy.

2-sec-butyl-4,5-dihydrothiazole is a ligand for mouse urinary protein and rat alpha 2u-globulin: physiological and toxicological relevance

Mouse urinary protein (MUP) and alpha 2u-globulin are structurally homologous proteins that belong to a superfamily of ligand-binding proteins and represent the major urinary proteins excreted by adult male mice and rats, respectively. Although a variety of xenobiotics bind to alpha 2u-globulin and produce a male rat-specific hyaline droplet nephropathy, no endogenous ligand for this protein has been identified. Despite extensive sequence homology. MUP does not bind to hyaline droplet-inducing agents. While performing experiments with purified MUP, we observed that it presented with a strong, distinctive odor reminiscent of mouse urine. To determine whether this odor was the result of contamination or degradation or was attributed to an endogenous ligand bound to the protein, the protein was subjected to thermal desorption and any released volatile compounds were detected with a gas chromatograph equipped with an external sniff port and mass spectrometer. With this approach, two odorous compounds were detected at the sniff port by a human observer, but only one was present in sufficient mass to allow identification. This compound, which presented with the characteristic odor, was subsequently identified as 2-sec butyl-4,5-dihydrothiazole (DHT) by GC/MS/matrix isolation IR and NMR analyses. The identification of DHT was confirmed by comparing the chromatographic and spectral properties to those of the synthesized authentic compound. In direct contrast, purified urinary alpha 2u-globulin did not present with an obvious odor, and no volatile ligands were detected on this protein. Although DHT is a major endogenous ligand for MUP, it was also found to competitively inhibit the binding of [14C]d-limonene-1,2-epoxide to alpha 2u-globulin with relatively high affinity (Ki = 2.3 microM). When dosed orally to F344 rats, DHT (1 mmol/kg for 3 days) caused the characteristic exacerbation of hyaline droplets in male rat kidneys and increased renal levels of immunoreactive alpha 2u-globulin about threefold over control levels. These results indicate that despite structural homology, MUP and alpha 2u-globulin are distinguished by the presence of a volatile endogenous ligand only on the former, a distinction that may reflect differences in the physiological functions of the two proteins. Furthermore, although DHT can bind to both MUP and alpha 2u-globulin, renal toxicity was only observed in rats, thereby emphasizing the unique toxicological properties of alpha 2u-globulin in the development of hyaline droplet nephropathy.

Development of an arabinose-fermenting Zymomonas mobilis strain by metabolic pathway engineering

The substrate fermentation range of the ethanologenic bacterium Zymomonas mobilis was expanded to include the pentose sugar, L-arabinose, which is commonly found in agricultural residues and other lignocellulosic biomass. Five genes, encoding L-arabinose isomerase (araA), L-ribulokinase (araB), L-ribulose-5-phosphate-4-epimerase (araD), transaldolase (talB), and transketolase (tktA), were isolated from Escherichia coli and introduced into Z. mobilis under the control of constitutive promoters that permitted their expression even in the presence of glucose. The engineered strain grew on and produced ethanol from L-arabinose as a sole C source at 98% of the maximum theoretical ethanol yield, based on the amount of consumed sugar. This indicates that arabinose was metabolized almost exclusively to ethanol as the sole fermentation product, with little by-product formation. Although no diauxic growth pattern was evident, the microorganism preferentially utilized glucose before arabinose, apparently reflecting the specificity of the indigenous facilitated diffusion transport system. This microorganism may be useful, along with the previously developed xylose-fermenting Z. mobilis (M. Zhang, C. Eddy, K. Deanda, M. Finkelstein, and S. Picataggio, Science 267:240-243, 1995), in a mixed culture for efficient fermentation of the predominant hexose and pentose sugars in agricultural residues and other lignocellulosic feedstocks to ethanol.

A technique for laparoscopic completion of vaginal hysterectomy

Recently, the use of laparoscopic assistance in vaginal hysterectomy has become popular, although its role in gynecologic surgery has not been well established. A way to define this role is to start the hysterectomy vaginally and use laparoscopic assistance only if it becomes necessary. We present a new technique in which vaginal hysterectomy proceeds to the opening of the peritoneal reflections and ligature of uterine vessels and uterosacral ligaments. If laparoscopic assistance becomes necessary at this point, a uterine manipulator with an adapted inflatable balloon is inserted vaginally, allowing completion of the procedure laparoscopically while maintaining a pneumoperitoneum. Eight operations were performed successfully in our institution using this new technique. Operative time was less than with conventional laparoscopically assisted vaginal hysterectomy. The technique also simplified the management of the uterine vessels and detachment of the bladder.

Imidazole acetol phosphate aminotransferase in Zymomonas mobilis: molecular genetic, biochemical, and evolutionary analyses

hisH encodes imidazole acetol phosphate (IAP) aminotransferase in Zymomonas mobilis and is located immediately upstream of tyrC, a gene which codes for cyclohexadienyl dehydrogenase. A plasmid containing hisH was able to complement an Escherichia coli histidine auxotroph which lacked the homologous aminotransferase. DNA sequencing of hisH revealed an open reading frame of 1,110 bp, encoding a protein of 40,631 Da. The cloned hisH product was purified from E. coli and estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis to have a molecular mass of 40,000 Da. Since the native enzyme had a molecular mass of 85,000 Da as determined by gel filtration, the active enzyme species must be a homodimer. The purified enzyme was able to transaminate aromatic amino acids and histidine in addition to histidinol phosphate. The existence of a single protein having broad substrate specificity was consistent with the constant ratio of activities obtained with different substrates following a variety of physical treatments (such as freeze-thaw, temperature inactivation, and manipulation of pyridoxal 5'-phosphate content). The purified enzyme did not require addition of pyridoxal 5'-phosphate, but dependence upon this cofactor was demonstrated following resolution of the enzyme and cofactor by hydroxylamine treatment. Kinetic data showed the classic ping-pong mechanism expected for aminotransferases. Km values of 0.17, 3.39, and 43.48 mM for histidinol phosphate, tyrosine, and phenylalanine were obtained. The gene structure around hisH-tyrC suggested an operon organization. The hisH-tyrC cluster in Z. mobilis is reminiscent of the hisH-tyrA component of a complex operon in Bacillus subtilis, which includes the tryptophan operon and aroE. Multiple alignment of all aminotransferase sequences available in the database showed that within the class I superfamily of aminotransferases, IAP aminotransferases (family I beta) are closer to the I gamma family (e.g., rat tyrosine aminotransferase) than to the I alpha family (e.g., rat aspartate aminotransferase or E. coli AspC). Signature motifs which distinguish the IAP aminotransferase family were identified in the region of the active-site lysine and in the region of the interdomain interface.

Metabolic Engineering of a Pentose Metabolism Pathway in Ethanologenic Zymomonas mobilis

The ethanol-producing bacterium Zymomonas mobilis was metabolically engineered to broaden its range of fermentable substrates to include the pentose sugar xylose. Two operons encoding xylose assimilation and pentose phosphate pathway enzymes were constructed and transformed into Z. mobilis in order to generate a strain that grew on xylose and efficiently fermented it to ethanol. Thus, anaerobic fermentation of a pentose sugar to ethanol was achieved through a combination of the pentose phosphate and Entner-Doudoroff pathways. Furthermore, this strain efficiently fermented both glucose and xylose, which is essential for economical conversion of lignocellulosic biomass to ethanol.

The contralateral corpus luteum and tubal pregnancy

One hundred fourteen cases of tubal pregnancy were examined for evidence of active or chronic salpingitis, other anatomic and functional etiologies, and the side of the corpus luteum relative to the pregnancy. A corpus luteum was found ipsilateral to the tubal pregnancy in 80 cases (70%) and contralateral in 18 (16%). In 16 cases (14%), the position of the corpus luteum could not be identified by inspection. No differences were noted among the groups in days from last normal menstrual period or the incidence of irregular bleeding. Of the 98 cases in which a corpus luteum was identified, 53 women (54%) had at least one condition that could be considered etiologic for tubal pregnancy, including 38 (39%) who had microscopic evidence of chronic salpingitis. No association was found between the laterality of the corpus luteum and the presence of risk factors, including mechanical factors. Possible explanations for absent corpora lutea in association with tubal pregnancies are discussed.