Two is not necessarily better than one: A double lens in a pre-metamorphic adult axolotl (Ambystoma mexicanum)

An 8-year-old female pre-metamorphic axolotl (Ambystoma mexicanum) was examined for a suspected anterior lens luxation. Slit-lamp biomicroscopy revealed two lens-like structures in the anterior chamber of the right eye (OD), each with cataractous change. Ultrasound biomicroscopy and optical coherence tomography (OCT) were performed without sedation, and revealed small lenticular structures each with distinct nuclei and cortices. Although a distinct connection of the two lenticular structures could not be definitively ruled out, the structures appeared separate. Each of the lenticular structures was closely associated with its respective iris leaflet. This report demonstrates application of advanced imaging for diagnostic use in axolotl ophthalmology, showing that imaging of the lens can be performed without sedation, topical anesthetic, nor contact gel with high diagnostic quality. Although two distinct lenses were diagnosed with no historical evidence of trauma, the small sizes of each lenticular structure, with no detectable connection between them, are suggestive of a possible regenerative abnormality. This report opens discussion for the regenerative capabilities of the pre-metamorphic adult axolotl and possible implementations of their use in regenerative medicine research for the development of future therapies.

Survivin as a therapeutic target in Sonic hedgehog-driven medulloblastoma

Medulloblastoma (MB) is a highly malignant brain tumor that occurs primarily in children. Although surgery, radiation and high-dose chemotherapy have led to increased survival, many MB patients still die from their disease, and patients who survive suffer severe long-term side effects as a consequence of treatment. Thus, more effective and less toxic therapies for MB are critically important. Development of such therapies depends in part on identification of genes that are necessary for growth and survival of tumor cells. Survivin is an inhibitor of apoptosis protein that regulates cell cycle progression and resistance to apoptosis, is frequently expressed in human MB and when expressed at high levels predicts poor clinical outcome. Therefore, we hypothesized that Survivin may have a critical role in growth and survival of MB cells and that targeting it may enhance MB therapy. Here we show that Survivin is overexpressed in tumors from patched (Ptch) mutant mice, a model of Sonic hedgehog (SHH)-driven MB. Genetic deletion of survivin in Ptch mutant tumor cells significantly inhibits proliferation and causes cell cycle arrest. Treatment with small-molecule antagonists of Survivin impairs proliferation and survival of both murine and human MB cells. Finally, Survivin antagonists impede growth of MB cells in vivo. These studies highlight the importance of Survivin in SHH-driven MB, and suggest that it may represent a novel therapeutic target in patients with this disease.

Clinical pharmacogenetics implementation consortium guidelines for CYP2C9 and HLA-B genotypes and phenytoin dosing

Phenytoin is a widely used antiepileptic drug with a narrow therapeutic index and large interpatient variability, partly due to genetic variations in the gene encoding cytochrome P450 (CYP)2C9 (CYP2C9). Furthermore, the variant allele HLA-B*15:02, encoding human leukocyte antigen, is associated with an increased risk of Stevens-Johnson syndrome and toxic epidermal necrolysis in response to phenytoin treatment. We summarize evidence from the published literature supporting these associations and provide recommendations for the use of phenytoin based on CYP2C9 and/or HLA-B genotype (also available on PharmGKB: http://www.pharmgkb.org). The purpose of this guideline is to provide information for the interpretation of HLA-B and/or CYP2C9 genotype tests so that the results can guide dosing and/or use of phenytoin. Detailed guidelines for the use of phenytoin as well as analyses of cost-effectiveness are out of scope. Clinical Pharmacogenetics Implementation Consortium (CPIC) guidelines are periodically updated at http://www.pharmgkb.org.

Performance of pattern recognition myoelectric control using a generic electrode grid with targeted muscle reinnervation patients

Targeted muscle reinnervation (TMR) is a surgical technique that creates myoelectric prosthesis control sites for high-level amputees. The electromyographic signal patterns provided by the reinnervated muscles are well-suited for pattern recognition (PR) control. PR control uses more electrodes compared to conventional amplitude control techniques but their placement on the residual limb is less critical than for conventional amplitude control. In this contribution, we demonstrate that classification error and real-time control performances using a generically placed electrode grid were equivalent or superior to the performance when using targeted electrode placements on two transhumeral amputee subjects with TMR. When using a grid electrode layout, subjects were able to complete actions 0.290 sec to 1 sec faster and with greater accuracy as compared to clinically localized electrode placement (mean classification error of 1.35% and 3.2%, respectively, for a 5 movement-class classifier).These findings indicate that a grid electrode arrangement has the potential to improve control of a myoelectric prosthesis while reducing the time and effort associated with fitting the prosthesis due to clinical localization of control sites on amputee patients.

UK surveillance: Provision of quality assured information from combined datasets

Surveillance information is most useful when provided within a risk framework, which is achieved by presenting results against an appropriate denominator. Often the datasets are captured separately and for different purposes, and will have inherent errors and biases that can be further confounded by the act of merging. The United Kingdom Rapid Analysis and Detection of Animal-related Risks (RADAR) system contains data from several sources and provides both data extracts for research purposes and reports for wider stakeholders. Considerable efforts are made to optimise the data in RADAR during the Extraction, Transformation and Loading (ETL) process. Despite efforts to ensure data quality, the final dataset inevitably contains some data errors and biases, most of which cannot be rectified during subsequent analysis. So, in order for users to establish the 'fitness for purpose' of data merged from more than one data source, Quality Statements are produced as defined within the overarching surveillance Quality Framework. These documents detail identified data errors and biases following ETL and report construction as well as relevant aspects of the datasets from which the data originated. This paper illustrates these issues using RADAR datasets, and describes how they can be minimised.

Progress with enhancing veterinary surveillance in the United Kingdom

The UK has experienced various animal health events that have had national impact in recent years. In response, a ;Veterinary Surveillance Strategy' (VSS) was published in 2003, with the objective of enhancing and coordinating national veterinary surveillance practice in a way that would enable important animal health events to be detected and assessed more rapidly and reliably. The VSS adopts an integrated UK-wide approach, which includes widespread engagement with interested parties both within government and beyond. It proposes enhancing surveillance through improved collaboration; transparent and defensible prioritisation of government resources to surveillance; deriving better value from existing resources, and assuring quality of the surveillance reports and source data. This article describes progress with implementing the VSS, in particular the methodology for developing a functional network and creating an effective, quality-assured, information management system, RADAR.

Thyroid cancer in pregnancy

OBJECTIVE

To compare stage at diagnosis, treatment and survival among pregnant women with thyroid cancer to non-pregnant women with thyroid cancer, and to assess the impact of treatment on maternal and perinatal outcomes.

METHODS

A database containing maternal and newborn discharge records linked to the California Cancer Registry was queried to obtain information on all thyroid cancers from 1991-1999. Women with thyroid cancer occurring during pregnancy were compared to age-matched non-pregnant women with thyroid cancer.

RESULTS

595 cases of thyroid cancers were identified (129 antepartum and 466 postpartum). About 64% of thyroid cancers were diagnosed at stage 2 among pregnant women versus 58% among non-pregnant controls. The odds of thyroid cancer were 1.5 times higher among Asian/Pacific Islanders than among Non-Hispanic White women. Pregnancy had no significant effect on mortality after diagnosis of thyroid cancer. Thyroidectomy during pregnancy was not associated with adverse maternal or neonatal outcomes.

CONCLUSIONS

Thyroid cancer discovered during or after pregnancy does not appear to have a significant impact on the prognosis of the disease.

Chemoradiation for primary invasive squamous carcinoma of the vagina

OBJECTIVE

To report outcomes for patients with primary, invasive, squamous carcinoma of the vagina treated with chemoradiation.

METHODS

Between 1986 and 1996, 14 patients were treated with primary therapy consisting of synchronous radiation and chemotherapy. Patients were judged not to be surgical candidates based on tumor size, location, and concerns related to urinary, bowel, or sexual function. Three patients were FIGO stage I, ten patients stage II, and one patient stage III. Radiation consisted of teletherapy alone (six patients) or in combination with intravaginal brachytherapy (eight patients). Total radiation dose ranged from 5700 to 7080 cGy (median 6300 cGy). Chemotherapy consisted of 5-fluorouracil alone (seven patients), or with cisplatin (six patients) or mitomycin-C (one patient).

RESULTS

One patient failed locally at 7 months and died of disease at 11 months. Four patients died of intercurrent illness (46, 92, 104, 109 months) and nine are alive and cancer-free 74-168 months after treatment (median 100 months). There were no vesicovaginal or enterovaginal fistulae.

CONCLUSIONS

Radiation with synchronous chemotherapy is an effective treatment for squamous carcinoma of the vagina. Cancer control outcomes compare favorably with previously published results employing higher dose radiation as monotherapy.

Chemoradiation for primary invasive squamous carcinoma of the vagina

Objective

To report outcomes for patients with primary, invasive, squamous carcinoma of the vagina treated with chemoradiation.

Methods

Between 1986 and 1996, 14 patients were treated with primary therapy consisting of synchronous radiation and chemotherapy. Patients were judged not to be surgical candidates based on tumor size, location, and concerns related to urinary, bowel, or sexual function. Three patients were FIGO stage I, ten patients stage II, and one patient stage III. Radiation consisted of teletherapy alone (six patients) or in combination with intravaginal brachytherapy (eight patients). Total radiation dose ranged from 5700 to 7080 cGy (median 6300 cGy). Chemotherapy consisted of 5-fluorouracil alone (seven patients), or with cisplatin (six patients) or mitomycin-C (one patient).

Results

One patient failed locally at 7 months and died of disease at 11 months. Four patients died of intercurrent illness (46, 92, 104, 109 months) and nine are alive and cancer-free 74–168 months after treatment (median 100 months). There were no vesicovaginal or enterovaginal fistulae.

Conclusions

Radiation with synchronous chemotherapy is an effective treatment for squamous carcinoma of the vagina. Cancer control outcomes compare favorably with previously published results employing higher dose radiation as monotherapy.

Endometriosis-related malignancies

The purpose of this study is to describe the clinical findings, treatment, and outcome of patients with endometriosis-related cancers. Patients meeting Sampson and Scott's criteria for cancer associated with endometriosis in the Sacramento region were identified by chart review and pathology reports. Twenty-seven patients were identified with endometriosis-related malignancies (mean age 51.4 years). The site of origin was ovary in 17 (63.0%) and extra-ovarian in 10 (37%) including vagina, fallopian tube or mesosalpinx, pelvic sidewall, colon, and parametrium. The pattern of spread was local in five (18.5%), regional in 20 (74.1%) and distant in two (7.4%). Six patients had taken unopposed estrogen replacement (mean duration 23.4 years) and all six had extragonadal disease. Surgical procedures included hysterectomy, salpingo-oophorectomy, radical local excision, partial colectomy, and surgical staging. Eighteen patients received postoperative chemotherapy since the majority of patients had ovarian involvement. Fifteen patients received regional radiation therapy. Nineteen patients are without evidence of recurrence (70.4%, mean follow-up of 31 months). Endometriosis-related malignancies have a favorable prognosis. Extragonadal disease was commonly associated with unopposed estrogen replacement therapy. The predominance of local and regional disease strongly influence the application of treatment modalities.

Altered morphology in cultured rat intestinal epithelial IEC-6 cells is associated with alkaline phosphatase expression

Non-transformed, rat intestinal epithelial cells (IEC-6), and human intestinal colonic carcinoma cells (CACO-2) have both been used to study processes of epithelial cell differentiation. However, only CACO-2 cells have been described as spontaneously expressing phenotypic changes of differentiation in culture. We report here that when IEC-6 cells are grown in post-confluent culture, they develop structural changes similar to those seen in cells induced to differentiate by culture on Englebreth-Holm-Swarm (EHS) extracellular matrix proteins. Correlated with this morphological change is loss of nuclear localization of c-myc protein and development of cell surface alkaline phosphatase (ALP) enzymatic activity. Messenger RNAs for liver and intestinal isoforms of ALP were expressed in both pre- and post-confluent cells. Inhibition of ALP activity in post-confluent cells by levamisole indicated the expressed ALP activity to be of the liver isoform. We suggest the expression of ALP activity, which occurs concomitantly with morphological alterations in post-confluent IEC-6 cells, represents increased expression and localization to the cell surface of the liver isoform of ALP. Cultured IEC-6 cells may provide a non-transformed, in vitro alternative to CACO-2 cells for study of epithelial cell differentiation.

Genetic diversity and transcriptional analysis of the bys1 gene from Blastomyces dermatitidis

Blastomyces dermatitidis, a pathogenic fungal organism, is able to exist in two different morphologies, a multicellular mycelium or a unicellular yeast, according to temperature, 25 degrees C and 37 degrees C respectively. The switching between morphologies must be accompanied by a cascade of signaling events in which expression of genes responsible for the change of morphology is increased or decreased. bys1, a gene from B. dermatitidis isolate #58, is expressed at high levels in the unicellular yeast, but gradually diminishes as the temperature is lowered and the organism converts to the mycelial phase where there is no transcription of bys1. We explored if bys1 homologs are found in other B. dermatitidis isolates and if the transcription of the homologs were regulated by temperature. bys1 was identified in all B. dermatitidis isolates tested and could be grouped into two classes by Southern blot, PCR, and DNA sequence. Although the bys1 transcripts of both classes were regulated by temperature, transcription rates varied between the three isolates tested.

Obstetrical deliveries associated with maternal malignancy in California, 1992 through 1997

OBJECTIVE

This study aims to characterize the rate of occurrence and nature of outcomes associated with obstetrical deliveries in women with malignant neoplasms among 3,168,911 women who delivered in California in 1992 through 1997.

DESIGN

The study is a population-based retrospective review of infant birth and death certificates and maternal and neonatal discharge records. Cases of malignant neoplasms associated with obstetrical delivery were attributed to 1 of 3 categories, depending on the earliest documented hospital discharge diagnosis, as follows: "prenatal" if the diagnosis was first documented by hospitalization within 9 months preceding delivery, "at delivery" if the diagnosis was established from the delivery hospitalization, or "postpartum" if the diagnosis was first documented by hospitalization within 12 months after delivery.

METHODS

Computer-linked infant birth and death certificates and maternal and neonatal discharge records were used to identify cases and outcomes. Cases of malignant neoplasms were identified by using International Classification of Diseases, Ninth Revision codes (140-208). Noninvasive neoplasms and carcinoma in situ neoplasms were excluded. In analysis of outcomes, the Mantel-Haenszel estimate for adjusted odds ratios was used.

RESULTS

Among 3,168,911 obstetrical deliveries over the 6-year span, a total of 2247 cases of primary malignancy were identified. The observed rate of occurrence for primary malignant neoplasms was 0.71 per 1000 live singleton births. Most cases (53.3%) were first documented in the postpartum period as follows: prenatal, 587 cases (0.18 per 1000); at delivery, 462 cases (0.15 per 1000); and postpartum, 1198 cases (0.38 per 1000). The most frequently documented primary malignant neoplasms associated with obstetrical delivery were breast cancer (423 cases, 0.13 per 1000), thyroid cancer (389 cases, 0.12 per 1000), cervical cancer (266 cases, 0.08 per 1000), Hodgkin's disease (172 cases, 0.05 per 1000), and ovarian cancer (123 cases, 0.04 per 1000). Odds ratios for a variety of demographic factors identified maternal age as the most significant risk factor for development of malignant neoplasms (age greater than 40 vs 20-25, odds ratio 5.7, CI 4.6-6.9). Age-adjusted odds ratios for maternal cancer of any type suggested significantly elevated risks for cesarean delivery (odds ratio 1.4, CI 1.3-1.6), blood transfusion (odds ratio 6.2, CI 4.5-8.5), hysterectomy (odds ratio 27.4, CI 20.8-36.1), and maternal postpartum hospital stay greater than 5 days (odds ratio 30.6, CI 27.9-33.6), but not for postpartum maternal death (odds ratio 0.8, CI 0.6-1.0). Odds ratios also suggested significantly elevated risks for premature newborn (odds ratio 2.0, CI 1.8-2.2), very low birth weight (odds ratio 2.9, CI 2.2-3.8), and newborn hospital stay longer than 5 days (odds ratio 2.6, CI 2.4-3.0), but not for neonatal death (odds ratio 1.6, CI 0.8-3.1) or infant death (odds ratio 1.2, CI 0.5-3.3). However, several types of malignant neoplasms did confer significant elevations in risk for neonatal death. Hospital charges for both maternal and neonatal care were significantly elevated in the maternal malignant neoplasm group.

CONCLUSION

A lower than expected occurrence rate of obstetrical delivery associated with maternal malignancy was seen when compared with previously published hospital-based reports. Malignant neoplasms associated with obstetrical delivery were most frequently first documented in the postpartum period. Maternal and neonatal morbidity were significantly increased, yet the risk of in-hospital maternal death was not significantly elevated. A significant increase in risk of neonatal death for infants of mothers with cervical cancer was found.

Cyclic AMP- and IL6-signaling cross talk: comodulation of proliferation and apoptosis in the 7TD1 B cell hybridoma

Proliferation of the 7TD1 B cell hybridoma is dependent on the survival factor interleukin-6 (IL6). IL6 inhibits physiological cell death and allows expansion of populations of serum-stimulated cells. In this report, we demonstrate that cyclic AMP (cAMP)- and IL6-dependent signaling pathways can interact, controlling proliferation of 7TD1 cells through modulation of apoptosis. Cyclic AMP analogues inhibited proliferation, as well as other treatments that increased intracellular cAMP. The cAMP-induced inhibition could be reversed after 24 h by the removal of dibutyryl-cAMP from the culture medium and readdition of IL6. In the absence of IL6, cAMP induced a slow loss of viable cells. This decrease in viable cells in the presence of cAMP was accompanied by a marked increase in apoptosis. The increase in apoptotic cells after 48 h was preceded at 24 h by a parallel increase in DEVD-caspase activity after treatment with cell-permeable cAMP analogues. Increased DEVD-caspase activity and subsequent apoptosis could both be blocked by the addition of IL6. These coregulating actions may represent a cross-talk signaling mechanism modulating cytokine activation of cellular proliferation and survival.

Phenotypic expression of primary hyperoxaluria: comparative features of types I and II

BACKGROUND

The primary hyperoxalurias are autosomal recessive disorders resulting from deficiency of hepatic alanine:glyoxylate aminotransferase (PHI) or D-glycerate dehydrogenase/glyoxylate reductase (PHII). Marked hyperoxaluria results in urolithiasis, renal failure, and systemic oxalosis. A direct comparison of PHI and PHII has not previously been available.

METHODS

Twelve patients with PHI and eight patients with PHII with an initial creatinine clearance of greater than or equal to 50 mL/min/1.73 m2 underwent similar laboratory evaluation, clinical management, and follow-up. Diagnosis of PHI and PHII was made by hepatic enzyme analysis (N = 11), increased urinary excretion of glycolate or glycerate (N = 7), or complete pyridoxine responsiveness (N = 2). Six PHI and five PHII patients had measurements of calcium oxalate crystalluria, urine supersaturation, and urine inhibition of calcium oxalate crystal formation.

RESULTS

PHI and PHII did not differ in age at the onset of symptoms, initial serum creatinine, or plasma oxalate concentration. Urine oxalate excretion rates were higher in PHI (2.19 +/- 0.61 mmol/1.73 m2/24 hours) than PHII (1.61 +/- 0.43, P = 0.04). Urine osmolality, calcium, citrate, and magnesium concentrations were lower in PHI than PHII (P = 0.001, P = 0.019, P = 0.0002, P = 0.03, respectively). Crystalluria scores and calcium oxalate inhibitory activity of the urine did not differ between PHI and PHII. Calcium oxalate supersaturation in the urine was less in PHI (7.3 +/- 1.9) compared with PHII (14.0 +/- 3.3, P = 0.002). During follow-up of 10.3 +/- 9. 6 years in PHI and 18.1 +/- 5.6 years in PHII, stone-forming activity and stone procedures were more frequent in PHI than PHII (P < 0.01 and P = 0.01, respectively). Four of 12 PHI compared with 0 of 8 PHII patients progressed to end-stage renal disease (P = 0.03).

CONCLUSION

The severity of disease expression is greater in type I primary hyperoxaluria than in type II. The difference may be due to greater oxalate excretion and lower concentrations of urine citrate and magnesium in patients with PHI compared with PHII.

Dietary restrictions for patients with neutropenia: a survey of institutional practices

PURPOSE/OBJECTIVES

To describe institutional practices related to dietary restrictions for patients with neutropenia to determine whether restrictions are used and when they are implemented and discontinued.

DESIGN

Descriptive survey.

SAMPLE

156 institutions belonging to the Association of Community Cancer Centers.

METHODS

Mailed survey.

FINDINGS

Of the institutions surveyed, 78% (n = 120) placed patients with neutropenia on restricted diets. Participating institutions responded that patients were placed on restricted diets at a variety of different white blood cell and neutrophil counts, including neutrophils < 1,000 (43%) and < 500 (46%). The majority of institutions (92%) placed patients on restricted diets once neutropenia was documented, while only 9% of institutions restricted diets when cancer treatment was initiated. Of the participating institutions, 83% (n = 96) restricted diets only when patients were neutropenic rather than throughout the duration of the chemotherapy regimen. The most commonly restricted foods were fresh fruits and juices (92%), fresh vegetables (95%), and raw eggs (74%). Few institutions restricted tap water (12%). Wine was restricted at 39% of institutions, and beer was restricted at 40% of institutions.

CONCLUSIONS

The role of diet in the development of infection in patients with neutropenia is unclear. This unclear role contributes to the variation in dietary restrictions among institutions.

IMPLICATIONS FOR NURSING PRACTICE

Additional research should focus on dietary factors contributing to neutropenic infections and establishing criteria for implementation of specific dietary modifications. Nursing assessment should include nutritional status and risk factors for neutropenia and bacterial translocation. Nursing protocols for neutropenic dietary restrictions should be based on research findings.

A gene expression database for the molecular pharmacology of cancer

We used cDNA microarrays to assess gene expression profiles in 60 human cancer cell lines used in a drug discovery screen by the National Cancer Institute. Using these data, we linked bioinformatics and chemoinformatics by correlating gene expression and drug activity patterns in the NCI60 lines. Clustering the cell lines on the basis of gene expression yielded relationships very different from those obtained by clustering the cell lines on the basis of their response to drugs. Gene-drug relationships for the clinical agents 5-fluorouracil and L-asparaginase exemplify how variations in the transcript levels of particular genes relate to mechanisms of drug sensitivity and resistance. This is the first study to integrate large databases on gene expression and molecular pharmacology.

MedMiner: an Internet text-mining tool for biomedical information, with application to gene expression profiling

The trend toward high-throughput techniques in molecular biology and the explosion of online scientific data threaten to overwhelm the ability of researchers to take full advantage of available information. This problem is particularly severe in the rapidly expanding area of gene expression experiments, for example, those carried out with cDNA microarrays or oligonucleotide chips. We present an Internet-based hypertext program, MedMiner, which filters and organizes large amounts of textual and structured information returned from public search engines like GeneCards and PubMed. We demonstrate the value of the approach for the analysis of gene expression data, but MedMiner can also be extended to other areas involving molecular genetic or pharmacological information. More generally still, MedMiner can be used to organize the information returned from any arbitrary PubMed search.

Measurement of atherosclerotic carotid plaque size in vivo using high resolution magnetic resonance imaging

BACKGROUND

Current imaging modalities, such as contrast angiography, accurately determine the degree of luminal narrowing but provide no direct information on plaque size. Magnetic resonance imaging (MRI), however, has potential for noninvasively determining arterial wall area (WA). This study was conducted to determine the accuracy of in vivo MRI for measuring the cross-sectional maximum wall area (MaxWA) of atherosclerotic carotid arteries in a group of patients undergoing carotid endarterectomy.

METHODS AND RESULTS

Fourteen patients scheduled for carotid endarterectomy underwent preoperative carotid MRI using a custom-made phased-array coil. The plaques were excised en bloc and scanned using similar imaging parameters. MaxWA measurements from the ex vivo MRI were used as the reference standard and compared with MaxWA measurements from the corresponding in vivo MR study. Agreement between the in vivo and ex vivo measurement was analyzed using the Bland-Altman method. The paired in vivo and ex vivo MaxWA measurements strongly agreed: the mean difference (in vivo minus ex vivo) in MaxWA was 13.1+/-6.5 mm2 for T1-weighted (T1W) imaging (mean MaxWA in vivo=94.7 mm2, ex vivo=81.6 mm2) and 14.1+/-11.7 mm2 for proton density-weighted (PDW) imaging (mean MaxWA in vivo=93.4 mm2, ex vivo=79.3 mm2). Intraobserver and interobserver variability was small, with intraclass correlation coefficients ranging from 0.90 to 0.98.

CONCLUSIONS

MRI is highly accurate for in vivo measurement of artery WA in atherosclerotic carotid lesions. This imaging technique has potential application monitoring lesion size in studies examining plaque progression and/or regression.

A functional calvin cycle is not indispensable for the light activation of C4 phosphoenolpyruvate carboxylase kinase and its target enzyme in the maize mutant bundle sheath defective2-mutable1

We used a pale-green maize (Zea mays L.) mutant that fails to accumulate ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) to test the working hypothesis that the regulatory phosphorylation of C4 phosphoenolpyruvate carboxylase (PEPC) by its Ca2+-insensitive protein-serine/threonine kinase (PEPC kinase) in the C4 mesophyll cytosol depends on cross-talk with a functional Calvin cycle in the bundle sheath. Wild-type (W22) and bundle sheath defective2-mutable1 (bsd2-m1) seeds were grown in a controlled environment chamber at 100 to 130 &mgr;mol m-2 s-1 photosynthetic photon flux density, and leaf tissue was harvested 11 d after sowing, following exposure to various light intensities. Immunoblot analysis showed no major difference in the amount of polypeptide present for several mesophyll- and bundle-sheath-specific photosynthetic enzymes apart from Rubisco, which was either completely absent or very much reduced in the mutant. Similarly, leaf net CO2-exchange analysis and in vitro radiometric Rubisco assays showed that no appreciable carbon fixation was occurring in the mutant. In contrast, the sensitivity of PEPC to malate inhibition in bsd2-m1 leaves decreased significantly with an increase in light intensity, and there was a concomitant increase in PEPC kinase activity, similar to that seen in wild-type leaf tissue. Thus, although bsd2-m1 mutant plants lack an operative Calvin cycle, light activation of PEPC kinase and its target enzyme are not grossly perturbed.

Clinical expression and long-term outcomes of primary hyperoxaluria types 1 and 2

Primary hyperoxaluria, types 1 and 2, are rare disorders. Much of the information in the literature has been derived from case reports and data registries limited to patients requiring dialysis and/or transplantation. We present a single-center experience of 42 patients and 437 patient years of clinical experience with primary hyperoxaluria. Median age at onset of symptoms for patients with type 1 PH was 9 years, type 2 15.7 years. Sixty-four percent of the patients were less than 15 years of age at onset of symptoms. There was no correlation between urine oxalate excretion rates and age at onset of symptoms. Stone forming activity was greater in patients with type 1 PH than type 2. Ten patients presented initially with ESRD, and an additional seven developed ESRD during the course of follow-up. ESRD occurred in 54 percent of the patients with type 1 and 12 percent of patients with type 2 PH. Eight patients received nine renal allografts, five patients received combined kidney/liver transplants, and one patient received a hepatic allograft only. Ten of the transplanted patients were surviving at the time of the most recent follow up. Eight of them have functioning renal grafts and four have functioning hepatic grafts. There have been no deaths since 1988 among the 32 patients followed since that time. These data may suggest a broad range of clinical expression of primary hyperoxaluria. With current management strategies, outcomes are more favorable than has been reflected in previous literature.

Prophylactic chemoradiation of inguinofemoral lymph nodes in patients with locally extensive vulvar cancer

OBJECTIVE

Primary surgical resection of locally advanced squamous cancer of the vulva may compromise the integrity of important midline structures such as the anus, clitoris, urethra, and vagina. Chemoradiation (synchronous radiation and cytotoxic chemotherapy) has been used as alternative initial treatment which may serve as definitive management for some patients, or may reduce the scope and functional sequelae of subsequent surgery in others. Inguinofemoral node dissection is associated with substantial risk of both acute and late morbidity, prompting consideration of elective inclusion of groin nodes within the irradiated volume and deletion of subsequent groin surgery. Concern that disease relapse in the groins is potentially fatal suggested the prudence of formal outcome assessment of our recent experience with prophylactic treatment of clinically uninvolved groin nodes in the context of concurrent chemoradiation for locally advanced primary vulvar cancer.

METHODS

A review was conducted of 23 previously untreated patients with locally advanced squamous cancer of the vulva (2 T2, 20 T3, 1 T4) and clinically uninvolved groin nodes (1969 FIGO stages 14 N0, 4 N1, and 5 N2 with negative node biopsies) who were treated since 1987 with chemoradiation administered to a volume electively including bilateral inguinofemoral nodes. These patients did not undergo subsequent groin surgery.

RESULTS

With follow-up from 6 to 98 months (mean, 45.3 months; median, 42 months), no patient has failed in the prophylactically irradiated inguinofemoral nodes. No patient has developed lymphedema, vascular insufficiency, or neurological injury in a lower extremity, and no patient has experienced aseptic necrosis of a femur.

CONCLUSIONS

Elective irradiation of the groin nodes in the context of initial chemoradiation for locally advanced vulvar cancer is an effective therapy associated with acceptable acute toxicity and minimal late sequelae. It constitutes a sensible alternative to groin dissection in this patient population.

Detection of serologic neutralizing antibodies against HPV-11 in patients with condyloma acuminata and cervical dysplasia using an in vitro assay

This study was designed to investigate if neutralizing antibodies against HPV-11 are detectable in the serum of patients with condyloma acuminata (CA) or cervical intraepithelial neoplasia (CIN) using an in vitro infectivity assay for HPV-11. Purified HPV-11 virions were extracted from xenografted condyloma tissues implanted into athymic mice and used to infect cultured neonatal human foreskin keratinocytes (HFK) and an immortalized adult skin cell line (HaCaT). The presence of HPV-11-specific E1--E4 mRNA as detected by reverse transcriptase-polymerase chain reaction was indicative of early infection. Sera previously characterized for reactivity to HPV-11 and HPV-11 VLP (virus-like particles) by ELISA were tested for the ability to prevent HPV-11 in vitro infectivity. Neutralizing antibodies against HPV-11 were demonstrated when monoclonal antibodies or patient serum preincubated with HPV-11 virions prevented the infection of either of the two cell cultures, as shown by the absence of the E1--E4 mRNA transcript. Eleven (of 20) patients with CA were strongly ELISA reactive against HPV-11 virus-like particles. Five of these 11 patients also had detectable levels of neutralizing antibodies in their serum. It was also demonstrated that the neutralizing properties of the serum were titratable by endpoint dilution. None of 15 patients with CIN had detectable neutralizing antibodies against HPV-11. Neutralizing antibodies against HPV-11 can be detected in some patients with CA and the neutralizing effects of the patient sera can be titrated by endpoint dilution. The in vitro assay for the detection of neutralizing antibodies against HPV-11 may have utility for investigating the natural history of HPV infection and resolution, as well as assessing the efficacy of any putative HPV vaccine.

Titration of HPV-11 infectivity and antibody neutralization can be measured in vitro

Human papillomavirus type 11 (HPV-11), produced from the athymic mouse xenograft system, was shown to infect cultured neonatal human foreskin keratinocytes and the HaCaT keratinocyte cell line in vitro. Infection was documented by the appearance of HPV-11-specific spliced mRNA, detected by reverse transcriptase-polymerase chain reaction. Purified HPV-11 virions at concentrations of approximately 10(7) particles/ml could successfully evoke infection in this system. Infection was completely abrogated by preincubation of the HPV-11 inoculum with mouse anti-HPV-11 monoclonal antibodies, experimentally immunized animal sera, or sera of human patients with HPV infection. Concurrent detection of cellular mRNA for the beta-actin gene, also by reverse transcriptase-polymerase chain reaction, provided an internal control confirming RNA recovery and successful reverse transcriptase-polymerase chain reaction. Using this approach, it was possible to determine semiquantitative titers for test solutions of HPV-11-neutralizing antibodies. The in vitro system for HPV-11 infectivity and neutralization may be useful in the study of the immune response to HPV-11 infection or immunization in patients.

Results of long-term treatment with orthophosphate and pyridoxine in patients with primary hyperoxaluria

BACKGROUND

The prognosis for patients with primary hyperoxaluria has been ominous, with the expectation of renal failure, poor results with transplantation, and early death.

METHODS

We studied the long-term effects of orthophosphate and pyridoxine therapy in 25 patients with primary hyperoxaluria who were treated for an average of 10 years (range, 0.3 to 26). Their mean age at the start of treatment was 12 years (median, 6; range, 0.5 to 32). We also studied the effect of orthophosphate and pyridoxine on urinary supersaturation with calcium oxalate, crystal inhibition using a seeded growth system, and crystal formation using scanning electron microscopy in 12 patients during three-day stays in the clinical research center.

RESULTS

The mean (+/- SD) glomerular filtration rate at the start of treatment was 91 +/- 26 ml per minute per 1.73 m2. The median decline in glomerular filtration rates was 1.4 ml per minute per 1.73 m2 of body-surface area per year. The actuarial survival free of end-stage renal disease was 96, 89, 74, and 74 percent of 5, 10, 15, and 20 years, respectively. Treatment with orthophosphate and pyridoxine reduced urinary supersaturation with calcium oxalate from 8.3 +/- 3.0 to 2.1 +/- 1.7 kJ per mole at 38 degrees C (P < 0.001), increased the inhibition of calcium oxalate formation from 63 +/- 11 to 108 +/- 10 inhibitor units per 24 hours (P < 0.001), and improved the crystalluria score from 2.6 +/- 0.3 to 0.6 +/- 0.1 (P < 0.001).

CONCLUSIONS

Treatment of patients with primary hyperoxaluria with orthophosphate and pyridoxine decreases urinary calcium oxalate crystallization and appears to preserve renal function.

Molecular evidence that the myxozoan protists are metazoans

The evolutionary origins of the protistan phylum, Myxozoa, have long been questioned. Although these obligate parasites are like protozoans in many features, several aspects of their ontogeny and morphology have implied a closer relationship to metazoan lineages. Phylogenetic analyses of 18S ribosomal RNA sequences from myxozoans and other eukaryotes, with the use of parsimony, distance, and maximum-likelihood methods, support the hypothesis that myxozoans are closely related to the bilateral animals. These results suggest that the Myxozoa, long considered an assemblage of protozoans, should be considered a metazoan phylum.

Cloning and characterization of bys1, a temperature-dependent cDNA specific to the yeast phase of the pathogenic dimorphic fungus Blastomyces dermatitidis

The pathogenic dimorphic fungal organism Blastomyces dermatitidis exists as a budding yeast at 37 degrees C and as a mycelium at 25 degrees C. While the conversion of one morphological phase of B. dermatitidis to another has long been known to be a thermally dependent process, little of the accompanying biochemical or genetic events controlling the phase transition has been elucidated. Using differential cDNA library screening, we have identified one transcript, bys1, in B. dermatitidis that is expressed at very high levels in the yeast phase but whose levels diminish rapidly when yeast cells are transferred to 25 degrees C to promote conversion to the mycelial phase. Although the 0.95-kb bys1 transcript is absent in B. dermatitidis mycelia maintained at 25 degrees C, transfer of mycelial cultures to 37 degrees C results in the reappearance of bys1 within 12 h. bys1 codes for a protein of 18.6 kDa that contains multiple putative phosphorylation sites, a hydrophobic N terminus, and two 34-amino-acid domains with similarly spaced nine-amino-acid degenerative repeating motifs. Although the nature of the thermal dependency of bys1 expression and the function of the bys1 protein are unknown, the strong expression of this transcript specifically in the yeast phase of B. dermatitidis may prove to be very useful in the development of more specific and sensitive diagnostic methods for blastomycosis.

Chemostratigraphy of predominantly siliciclastic Neoproterozoic successions: a case study of the Pocatello Formation and Lower Brigham Group, Idaho, USA

Isotopic chemostratigraphy has proven successful in the correlation of carbonate-rich Neoproterozoic successions. In successions dominated by siliciclastic rocks, chemostratigraphy can be problematic, but if thin carbonates punctuate siliciclastic strata, useful isotopic data may be obtained. The upper Pocatello Formation and lower Brigham Group of southeastern Idaho provide an opportunity to assess the potential and limitations of isotopic chemostratigraphy in overwhelmingly siliciclastic successions. The 5000 m thick succession consists predominantly of siliciclastic lithologies, with only three intervals that contain thin intercalated carbonates. Its depositional age is only broadly constrained by existing biostratigraphic, sequence stratigraphic and geochronometric data. The lowermost carbonates include a cap dolomite atop diamictites and volcanic rocks of the Pocatello Formation. The delta 13C values of these carbonates are distintly negative (-5 to -3), similar to carbonates that overlie Neoproterozoic glaciogenic rocks worldwide. Stratigraphically higher carbonates record a major positive delta 13C excursion to values as high as +8.8 within the carbonate member of the Caddy Canyon Quartzite. The magnitude of this excusion is consistent with post-Sturtian secular variation recorded elsewhere in the North American Cordillera, Australia, Svalbard, Brazil and Nambia, and exceeds the magnitude of any post-Varanger delta 13C excursion documented to date. In most samples, Sr-isotopic abundances have been altered by diagenesis and greenschist facies metamorphism, but a least-altered value of approximately 0.7076 supports a post-Sturtian and pre-Marinoan/Varanger age for upper Pocatello and lower Brigham rocks that lie above the Pocatello diamictite. Thus, even though available chemostratigraphic data are limited, they corroborate correlations of Pocatello Formation diamictites and overlying units with Sturtian glaciogenic rocks and immediately post-Sturtian successions in western North America and elsewhere.

Dietary management of urolithiasis

Within the United States, 5% to 15% of the population will have a symptomatic episode of a stone within the urinary tract by the age of 70. At least 50% of these individuals will have recurrent stone formation if left untreated. The composition of urine from which these stones are formed and in which they grow is, in part, dependent on diet, including fluid intake. The volume of urine is an important determinant of solute concentration. Ionic strength, pH, and the concentration of the major ionic species present in urine determine the level of saturation for any crystal system that could be precipitating. There are many conditions that can be complicated by the formation of calculi within the urinary tract. Identifying the dietary factors that are contributing to the problem and correcting these abnormalities are the foundations for good medical management. This review identifies dietary components that need to be considered in the management of affected patients and considers specific medical problems that may be especially influenced by diet and fluid intake.

Long-term prognosis in primary hyperoxaluria type II (L-glyceric aciduria)

Primary hyperoxaluria type II (PH-II) or L-glyceric aciduria was first reported by Williams and Smith in 1968 (N Engl J Med 278:233-239, 1968). Deficiencies of D-glycerate dehydrogenase and glyoxylate reductase activity in patients with this disorder leads to increases in urinary oxalate and glycerate excretion. Clinically, PH-II presents in a similar fashion to the more common variant of the disorder, PH-I, with symptoms of calcium oxalate nephrolithiasis. To date, 16 patients with PH-II have been described, and information regarding follow-up is available in only three. We review these reports and present five additional patients from three families, four of whom have been followed closely for more than 20 years. The favorable long-term outcome of our patients over 110 patient-years, as determined by renal function testing and radiographic evaluation, suggests that PH-II may have a more favorable prognosis when compared with the natural history of PH-I. Systematic screening of all PH patients in our practice led to the discovery of five of 30 with PH-II, thus suggesting that this subset population may be more common than originally suspected.

T-type and L-type calcium currents in freshly dispersed human uterine smooth muscle cells

OBJECTIVE

Our purpose was to characterize the types of voltage-activated calcium currents that are found in human uterine myocytes and to determine the effects of magnesium and nifedipine on these currents.

STUDY DESIGN

Electrophysiologic experiments were performed on freshly isolated human uterine smooth muscle cells by means of the nystatin modification of the whole-cell patch clamp technique.

RESULTS

Two types of voltage-activated calcium currents that are similar to the T-type and L-type calcium currents observed in cardiac myocytes were identified in freshly dispersed, pregnant human uterine myocytes. Magnesium at 8 mmol/L reduced uterine myocyte T-type currents by 68% +/- 17% but did not reduce L-type currents. Nifedipine at 10(-6) mol/L blocked the L-type currents but had no effect on T-type currents.

CONCLUSION

Freshly isolated human uterine smooth muscle cells exhibit subtypes of calcium currents that are analogous to those found in cardiac myocytes. The uterine myocyte T-type current may be primarily involved with action potential transmission and the L-type current primarily with increasing intracellular free calcium by bulk calcium transport. The differing physiologic effects of magnesium and nifedipine on the calcium current subtypes suggest that for the treatment of preterm labor the primary effect of magnesium therapy is to decrease the frequency of contractions and of nifedipine the strength.

In vitro HPV-11 infection of human foreskin

Study of the infectious process of human papillomavirus type 11 (HPV-11) has been facilitated by the discovery that HPV-11-infected neonatal human foreskin epithelium can proliferate as xenografts into condyloma-like growths within athymic nude mice. Here we describe detection of HPV-11 infection of neonatal human foreskin-derived keratinocytes, infected and cultured entirely in vitro, by use of the polymerase chain reaction and primers straddling the splice donor/acceptor site of the most prevalent early gene HPV-11 transcript (E1 increase E4). Expression of the E1 increase E4 HPV-11 mRNA is abrogated by 60 degrees C heat inactivation of the inoculum. HPV-11-infected foreskin explants continue to produce the E1 increase E4 mRNA for up to 5 weeks in culture, and second-passage keratinocytes derived from infected explant outgrowths continue to produce the E1 increase E4 mRNA. The in vitro system described here provides a new way to study HPV-11 infection and may be useful in evaluating early events of infection.

Urinary oxalate and glycolate excretion patterns in the first year of life: a longitudinal study

To determine the range of normal values, we studied urinary excretion of oxalate and glycolate prospectively and longitudinally in a cohort of 30 healthy term infants. Random urine samples were obtained at 2 days, 2 weeks, and 2, 4, 6, and 9 months of age. The results had a log-normal distribution. The mean oxalate/creatinine ratio, as determined by the oxalate oxidase method, was 0.08 (in milligrams of oxalate to milligrams of creatinine) with a normalized range of 0.02 to 0.31. The mean ratio when oxalates were measured by using the Olthuis assay was 0.13 (range 0.03 to 0.53). The mean glycolate/creatinine ratio was 0.07 (range 0.02 to 0.26). These values did not correlate with increasing age. The oxalate/creatinine ratios were higher in formula-fed infants than in those who were fed human milk (0.14 +/- 0.16 vs 0.08 +/- 0.04; p < 0.01).

Condylomata acuminata. Roles of different techniques of laser vaporization

Eighty-four women with acuminate warts of the external genital tract were treated with two methods of laser vaporization. Patients were classified by lesion number and volume (1+, 2+, 3+). Thirty-three patients had only the lesions vaporized, whereas 51 had individual lesions vaporized followed by the "brushing" technique applied to the surrounding mucosa. Postoperative discomfort and pain were worse in those patients who had the brushing technique. The results were assessed colposcopically six to eight weeks postoperatively. Regardless of the method of laser vaporization, the majority of patients with extensive disease (2+ or 3+) had persistent lesions, although reduced in number in most instances. Patients with relatively few lesions (1+) had complete elimination of the warts whether or not brushing was employed. Based upon this study, reducing the burden of acuminate warts before laser vaporization is recommended.

Retroperitoneal fibrosis as a cause of hypertension in an aviator: a case report

The authors describe a case report of a previously healthy rotary-wing aviator who developed hypertension of unknown etiology. His 30 pack/year smoking history and hypercholesterolemia (ranging from 224-268) were significant. The initial evaluation revealed an elevated creatinine of 1.7 (normal to 1.5). Right-sided hydronephrosis was noted on ultrasound and the right kidney was poorly visualized on IVP. A subsequent retrograde cystoureterogram confirmed the hydronephrosis and demonstrated a distal calculus and stenosis, findings which were compatible with retroperitoneal fibrosis (RPF). This diagnosis was confirmed at surgery and the patient's ureters were freed. Following surgery, return of normal kidney function and satisfactory recovery, this aviator returned to full flying duty. A review of RPF is included.

Role of ultrasound in medical management of patients with renal stone disease

Eighty-three patients with radiographically opaque renal stones were evaluated prospectively with ultrasound and compared to KUB (kidneys, ureters, bladder) with tomograms (KUB/T) to further define the use of ultrasound in the evaluation of renal calculi. The presence or absence and the size, number, and location of stones were analyzed and correlated for each modality. Ultrasound detected the presence of renal stones in 77 of 83 (93%) patients. However, all of the stones were detected on ultrasound in only 60% of these patients. Thirty percent (80 of 269) of the papillary-calyceal stones seen on KUB/T were missed on US; 66% of the stones missed measured 2 mm or less. Although ultrasound can be used for detection of intrarenal stones, KUB/T is a more accurate imaging examination for determination of size and number of small stones.

Synchronous radiation and cytotoxic chemotherapy for locally advanced or recurrent squamous cancer of the vulva

Between July 1987 and September 1991 a program of external beam radiation and synchronous, radiopotentiating chemotherapy was employed to treat 25 women with locoregionally advanced or locoregionally recurrent squamous cancer of the vulva. Of 18 previously untreated patients, 1 was Stage II, 10 were Stage III, 6 were Stage IVA, and 1 was Stage IVB. Reasons for patient referral for nonsurgical management included the presence of initially unresectable disease (5 patients), disease extent which would have necessitated partial or total exenteration if treated surgically (9 patients), disease extent predictive of inadequate surgical margins (less than 1 cm gross margin) if treated by less than exenterative surgery (8 patients), and severe comorbid illness precluding surgical management (3 patients). Complete clinical response was obtained in 16 of 18 previously untreated patients (89%) and in 4 of 7 patients with recurrent disease following vulvar surgery (57%). Of 20 patients achieving a complete clinical response, 3 patients have relapsed within the irradiated volume at 11, 38, and 48 months following completion of treatment. Fourteen patients remain alive and continuously cancer free from 2-52 months after completion of treatment (median follow-up 24 months). This experience suggests that initial management with radiation and chemotherapy may offer some patients with locally advanced squamous cancer of the vulva an alternative to exenterative surgery and may hold curative potential for some patients with surgically unresectable or medically inoperable disease.

Management of neutropenic enterocolitis in the patient with cancer

Neutropenic enterocolitis is a life-threatening condition often seen in patients experiencing prolonged periods of neutropenia from conditions such as leukemia and lymphoma and from aggressive chemotherapy regimens. Its exact pathologic process remains unclear; however, it has been proposed that direct cytotoxic damage occurs to the bowel mucosa with subsequent microbial invasion complicated by the lack of adequate neutrophil response. The damage may progress to bowel perforation and septic shock. Early recognition and management by healthcare team members are crucial for the improved prognosis of these individuals. Controversy continues to exist concerning management options and the timing of these interventions. This article outlines nursing and medical management of the patient with neutropenic enterocolitis.