Environmental life cycle assessment of production of the high intensity sweetener steviol glycosides from Stevia rebaudiana leaf grown in Europe: The SWEET project

PURPOSE

There is an increasing interest in the use of non-nutritive sweeteners to replace added sugar in food and beverage products for reasons of improving consumer health. Much work has been done to understand safety of sweeteners, but very little on sustainability. To address that gap, this study presents the results of a life cycle assessment (LCA) of production of rebaudioside A 60%, 95% pure (RA60) steviol glycoside mix from Stevia rebaudiana leaf grown in Europe.

METHODS

An attributional cradle-to-factory-gate life cycle assessment was conducted on growing of stevia leaves and extraction of steviol glycosides in Europe. Primary data were used from a case study supply chain. Results are reported in impact categories from the ReCiPe 2016 (H) method, with focus given to global warming potential, freshwater eutrophication, water consumption, and land use. Impacts are expressed both in terms of production mass and sweetness equivalence, a common metric for understanding high intensity sweetener potency. Sweetness equivalence of RA60 is typically 200 to 300 times that of sugar. Comparison of environmental impact is made to sugar (sucrose) produced from both cane and beets. The research is part of the EU project SWEET (sweeteners and sweetness enhancers: impact on health, obesity, safety, and sustainability).

RESULTS AND DISCUSSION

Global warming potential for production of RA60 was found to be 20.25 kgCO₂-eq/kg_RA60 on a mass basis and 0.081 kgCO₂-eq/kg_SE on a sweetness equivalence basis. Field production of stevia leaves was found to be the main source of impact for most impact categories, and for all four focus categories. Extraction of the RA60 was the main source of impact for the others. Leaf processing and seedling propagation were minor contributors to life cycle impact. Removal of international transport from the supply chain reduced global warming potential by 18.8%. Compared with sugar on a sweetness equivalence basis, RA60 has approximately 5.7% to 10.2% the impact for global warming potential, 5.6% to 7.2% the impact for land use, and is lower across most other impact categories.

CONCLUSION

This is the first LCA of steviol glycoside mix RA60 produced from leaf in Europe. The results indicate that RA60 can be used to reduce environmental impact of providing a sweet taste by replacing sugar across all impact categories. However, it is important to note that specific formulations in which RA60 is used will have a bearing on the final environmental impact of any food or beverage products. For solid foods, this requires further research.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s11367-022-02127-9.

Clarin-2 is essential for hearing by maintaining stereocilia integrity and function

Hearing relies on mechanically gated ion channels present in the actin-rich stereocilia bundles at the apical surface of cochlear hair cells. Our knowledge of the mechanisms underlying the formation and maintenance of the sound-receptive structure is limited. Utilizing a large-scale forward genetic screen in mice, genome mapping and gene complementation tests, we identified Clrn2 as a new deafness gene. The Clrn2clarinet/clarinet mice (p.Trp4* mutation) exhibit a progressive, early-onset hearing loss, with no overt retinal deficits. Utilizing data from the UK Biobank study, we could show that CLRN2 is involved in human non-syndromic progressive hearing loss. Our in-depth morphological, molecular and functional investigations establish that while it is not required for initial formation of cochlear sensory hair cell stereocilia bundles, clarin-2 is critical for maintaining normal bundle integrity and functioning. In the differentiating hair bundles, lack of clarin-2 leads to loss of mechano-electrical transduction, followed by selective progressive loss of the transducing stereocilia. Together, our findings demonstrate a key role for clarin-2 in mammalian hearing, providing insights into the interplay between mechano-electrical transduction and stereocilia maintenance.

Novel gene function revealed by mouse mutagenesis screens for models of age-related disease

Determining the genetic bases of age-related disease remains a major challenge requiring a spectrum of approaches from human and clinical genetics to the utilization of model organism studies. Here we report a large-scale genetic screen in mice employing a phenotype-driven discovery platform to identify mutations resulting in age-related disease, both late-onset and progressive. We have utilized N-ethyl-N-nitrosourea mutagenesis to generate pedigrees of mutagenized mice that were subject to recurrent screens for mutant phenotypes as the mice aged. In total, we identify 105 distinct mutant lines from 157 pedigrees analysed, out of which 27 are late-onset phenotypes across a range of physiological systems. Using whole-genome sequencing we uncover the underlying genes for 44 of these mutant phenotypes, including 12 late-onset phenotypes. These genes reveal a number of novel pathways involved with age-related disease. We illustrate our findings by the recovery and characterization of a novel mouse model of age-related hearing loss.

Random mutagenesis can uncover novel genes involved in phenotypic traits. Here the authors perform a large-scale phenotypic screen on over 100 mouse strains generated by ENU mutagenesis to identify mice with age-related diseases, which they attribute to specific mutations revealed by whole-genome sequencing.

The goya mouse mutant reveals distinct newly identified roles for MAP3K1 in the development and survival of cochlear sensory hair cells

Mitogen-activated protein kinase, MAP3K1, plays an important role in a number of cellular processes, including epithelial migration during eye organogenesis. In addition, studies in keratinocytes indicate that MAP3K1 signalling through JNK is important for actin stress fibre formation and cell migration. However, MAP3K1 can also act independently of JNK in the regulation of cell proliferation and apoptosis. We have identified a mouse mutant, goya, which exhibits the eyes-open-at-birth and microphthalmia phenotypes. In addition, these mice also have hearing loss. The goya mice carry a splice site mutation in the Map3k1 gene. We show that goya and kinase-deficient Map3k1 homozygotes initially develop supernumerary cochlear outer hair cells (OHCs) that subsequently degenerate, and a progressive profound hearing loss is observed by 9 weeks of age. Heterozygote mice also develop supernumerary OHCs, but no cellular degeneration or hearing loss is observed. MAP3K1 is expressed in a number of inner-ear cell types, including outer and inner hair cells, stria vascularis and spiral ganglion. Investigation of targets downstream of MAP3K1 identified an increase in p38 phosphorylation (Thr180/Tyr182) in multiple cochlear tissues. We also show that the extra OHCs do not arise from aberrant control of proliferation via p27KIP1. The identification of the goya mutant reveals a signalling molecule involved with hair-cell development and survival. Mammalian hair cells do not have the ability to regenerate after damage, which can lead to irreversible sensorineural hearing loss. Given the observed goya phenotype, and the many diverse cellular processes that MAP3K1 is known to act upon, further investigation of this model might help to elaborate upon the mechanisms underlying sensory hair cell specification, and pathways important for their survival. In addition, MAP3K1 is revealed as a new candidate gene for human sensorineural hearing loss.

Summary: The ENU-derived mouse mutant goya, reveals, for the first time, multiple roles of MAP3K1 in cochlear development and correct auditory function.

Interactions between the otitis media gene, Fbxo11, and p53 in the mouse embryonic lung

Otitis media with effusion (OME) is the most common cause of hearing loss in children, and tympanostomy (ear tube insertion) to alleviate the condition remains the commonest surgical intervention in children in the developed world. Chronic and recurrent forms of otitis media (OM) are known to have a very substantial genetic component; however, until recently, little was known of the underlying genes involved. The Jeff mouse mutant carries a mutation in the Fbxo11 gene, a member of the F-box family, and develops deafness due to a chronic proliferative OM. We previously reported that Fbxo11 is involved in the regulation of transforming growth factor beta (TGF-β) signalling by regulating the levels of phospho-Smad2 in the epithelial cells of palatal shelves, eyelids and airways of the lungs. It has been proposed that FBXO11 regulates the cell's response to TGF-β through the ubiquitination of CDT2. Additional substrates for FBXO11 have been identified, including p53. Here, we have studied both the genetic and biochemical interactions between FBXO11 and p53 in order to better understand the function of FBXO11 in epithelial development and its potential role in OM. In mice, we show that p53 (also known as Tp53) homozygous mutants and double heterozygous mutants (Jf/+ p53/+) exhibit similar epithelial developmental defects to Fbxo11 homozygotes. FBXO11 and p53 interact in the embryonic lung, and mutation in Fbxo11 prevents the interaction with p53. Both p53 and double mutants show raised levels of pSMAD2, recapitulating that seen in Fbxo11 homozygotes. Overall, our results support the conclusion that FBXO11 regulates the TGF-β pathway in the embryonic lung via cross-talk with p53.

Summary: Genetic interactions between Fbxo11 and p53 illustrate the cross-talk between the TGF-β and p53 signalling pathways in epithelial development, with implications for the underlying molecular pathology of otitis media.

Otitis media in the Tgif knockout mouse implicates TGFβ signalling in chronic middle ear inflammatory disease

Otitis media with effusion (OME) is the most common cause of hearing loss in children and tympanostomy to alleviate the condition remains the commonest surgical intervention in children in the developed world. Chronic and recurrent forms of OM are known to have a very significant genetic component, however, until recently little was known of the underlying genes involved. The identification of mouse models of chronic OM has indicated a role of transforming growth factor beta (TGFβ) signalling and its impact on responses to hypoxia in the inflamed middle ear. We have, therefore, investigated the role of TGFβ signalling and identified and characterized a new model of chronic OM carrying a mutation in the gene for transforming growth interacting factor 1 (Tgif1). Tgif1 homozygous mutant mice have significantly raised auditory thresholds due to a conductive deafness arising from a chronic effusion starting at around 3 weeks of age. The OM is accompanied by a significant thickening of the middle ear mucosa lining, expansion of mucin-secreting goblet cell populations and raised levels of vascular endothelial growth factor, TNF-α and IL-1β in ear fluids. We also identified downstream effects on TGFβ signalling in middle ear epithelia at the time of development of chronic OM. Both phosphorylated SMAD2 and p21 levels were lowered in the homozygous mutant, demonstrating a suppression of the TGFβ pathway. The identification and characterization of the Tgif mutant supports the role of TGFβ signalling in the development of chronic OM and provides an important candidate gene for genetic studies in the human population.

Nanoindentation of Bone in a Physiological Environment

Nanoindentation has been established as an effective method to measure the mechanical properties of bone tissue at the micron and sub-micron length scale. Although it is well-documented that the mechanical properties of macroscopic bone specimens vary depending on whether the samples are tested dry or wet, nanoindentation is generally conducted on dehydrated bone tissue at room temperature, primarily because nanoindentation systems are extremely sensitive to changes in environmental conditions such as humidity and temperature. In this study, these problems were overcome by using a specially constructed liquid cell with an extension piece that allowed the indenter tip to be submerged under 5 mm of liquid. The custom setup was used to test cortical bovine bone and cancellous human bone specimens in three distinct conditions – dehydrated, rehydrated in simulated body fluid (SBF) at 20°C, and rehydrated in SBF at 37.5°C. A heating element with a temperature control unit was used to test at 37.5°C. The hardness and elastic modulus of the bone samples were found to decrease when dry specimens were rehydrated and tested in physiological conditions. It is suggested that nanoindentation in physiological conditions gives a better estimate of the mechanical properties of the microstructural components of bone in vivo rather than nanoindentation under conventional conditions.

Nanoindentation of Bone in a Physiological Environment

Nanoindentation has been established as an effective method to measure the mechanical properties of bone tissue at the micron and sub-micron length scale. Although it is well-documented that the mechanical properties of macroscopic bone specimens vary depending on whether the samples are tested dry or wet, nanoindentation is generally conducted on dehydrated bone tissue at room temperature, primarily because nanoindentation systems are extremely sensitive to changes in environmental conditions such as humidity and temperature. In this study, these problems were overcome by using a specially constructed liquid cell with an extension piece that allowed the indenter tip to be submerged under 5 mm of liquid. The custom setup was used to test cortical bovine bone and cancellous human bone specimens in three distinct conditions – dehydrated, rehydrated in simulated body fluid (SBF) at 20°C, and rehydrated in SBF at 37.5°C. A heating element with a temperature control unit was used to test at 37.5°C. The hardness and elastic modulus of the bone samples were found to decrease when dry specimens were rehydrated and tested in physiological conditions. It is suggested that nanoindentation in physiological conditions gives a better estimate of the mechanical properties of the microstructural components of bone in vivo rather than nanoindentation under conventional conditions.

Primary treatment of pelvic osteosarcoma: Report of five cases

Five patients, ages 12 to 20 years, with nonresectable primary (Patients 2, 3, and 5) and metastatic (Patients 1 and 4) pelvic osteosarcomas were treated with intraarterial cisplatin and concurrent radiation therapy from 1983 to 1987. Long-term local tumor control was achieved in all five patients. Patients 1 and 3 are alive with no evidence of local recurrence or metastatic disease at 77 and 56 months of follow-up, respectively, since diagnosis of the pelvic tumor. Patients 2, 4, and 5 died of metastatic lung disease at 25, 39, and 12 months, respectively, after diagnosis of the pelvic tumor. Patient 4 had no clinical or radiologic evidence of local recurrence. Control of tumor growth in patients with pelvic osteosarcomas can be achieved with regional chemotherapy and concurrent radiation therapy. These patients also should receive adjuvant intensive systemic chemotherapy to increase the probability of eliminating potential subclinical metastatic disease.

THE ELECTRIC RESISTANCE AND CAPACITY OF BLOOD FOR FREQUENCIES BETWEEN 800 AND 4(1/2) MILLION CYCLES

1. The variation of the experimental values (R (ω)), (C (ω)) of the resistance and capacity of blood for increasing frequencies is approximately represented by the equation: See PDF for Equation in which R_o and C_o are the resistance and capacity of the blood at low frequency and See PDF for Equation is the resistance of the blood at infinite frequency. Formulæ (1) and (2) are derived by considering the blood as equivalent to the system shown in the diagram (a) of Fig. 1. 2. By the application of formula (1) to our experimental data the value of R(∞) can be extrapolated with high accuracy. R(∞) represents the resistance) which would have been obtained at low frequency, if the membranes around the corpuscles could have been removed. 3. The specific resistance of the corpuscle interior can be calculated by equation (5), using experimental values for R(∞), for the volume concentration of the blood and for the specific resistance of the serum. 4. The specific resistance of the interior of the red corpuscle of the calf is found to be 3.5 ± 10 per cent times the specific resistance of the serum.

Regulation of TGF-beta signalling by Fbxo11, the gene mutated in the Jeff otitis media mouse mutant

Background

Jeff is a dominant mouse mutant displaying chronic otitis media. The gene underlying Jeff is Fbxo11, a member of the large F-box family, which are specificity factors for the SCF E3 ubiquitin ligase complex. Jeff homozygotes die shortly after birth displaying a number of developmental abnormalities including cleft palate and eyes open at birth. TGF-β signalling is involved in a number of epithelial developmental processes and we have investigated the impact of the Jeff mutation on the expression of this pathway.

Results

Phospho-Smad2 (pSmad2) is significantly upregulated in epithelia of Jeff homozygotes. Moreover, there was a significant increase in nuclear localization of pSmad2 in contrast to wild type. Mice heterozygous for both Jeff and Smad2 mutations recapitulate many of the features of the Jeff homozygous phenotype. However, tissue immunoprecipitations failed to detect any interaction between Fbxo11 and Smad2. Fbxo11 is known to neddylate p53, a co-factor of pSmad2, but we did not find any evidence of genetic interactions between Jeff and p53 mutants. Nevertheless, p53 levels are substantially reduced in Jeff mice suggesting that Fbxo11 plays a role in stabilizing p53.

Conclusion

Overall, our findings support a model whereby Fbxo11, possibly via stabilization of p53, is required to limit the accumulation of pSmad2 in the nucleus of epithelial cells of palatal shelves, eyelids and airways of the lungs. The finding that Fbxo11 impacts upon TGF-β signalling has important implications for our understanding of the underlying disease mechanisms of middle ear inflammatory disease.

Attentional and processing skills following traumatic brain injury in early childhood

PRIMARY OBJECTIVE

Attentional deficits are common following TBI in adults. This study examined whether these skills are also vulnerable following early childhood injury, when such skills are rapidly developing.

RESEARCH DESIGN

This study investigated attention 30 months post-TBI in pre-schoolers (n=56) and age-matched controls (n=26). TBI children were divided into mild, moderate and severe injury groups.

METHODS AND PROCEDURE

Pre-injury data were collected at time of injury. Assessment of attention included the Continuous Performance Test, Wechsler Intelligence Scale and Personality Inventory for Children.

MAIN OUTCOMES AND RESULTS

Severe TBI was associated with reduced accuracy and slowed processing, particularly on complex motor responses. Sustained attention was more intact. Parental reports indicate internalized behavioural problems and somatic complaints.

CONCLUSIONS

Young children with severe TBI are at risk for severe, persisting attentional impairments. Children with mild and moderate TBI show better outcome, with pre-injury behaviour and age also predictive of attentional skills at 30 months post-injury.

Identifying factors contributing to child and family outcome 30 months after traumatic brain injury in children

OBJECTIVE

To examine the contributions of injury severity, physical and cognitive disability, child and family function to outcome 30 months after traumatic brain injury (TBI) in children.

DESIGN

A prospective, longitudinal, between group design, comparing function before and after injury across three levels of injury severity.

SUBJECTS

One hundred and fifty children, 3.0-12.11 years old, admitted to hospital with a diagnosis of TBI. The sample was divided according to injury severity: mild (n = 42), moderate (n = 70), severe (n = 38). Children with a history of neurological, developmental, and psychiatric disorders were excluded from participation.

MAIN OUTCOME MEASURES

Post injury physical function, cognitive ability (incorporating intellect, memory, and attention), behavioural and family functioning, and level of family burden.

RESULTS

A dose-response relation was identified for injury severity and physical and cognitive outcome, with significant recovery documented from acute to six months after TBI. Behavioural functioning was not related to injury severity, and where problems were identified, little recovery was noted over time. Family functioning remained unchanged from preinjury to post injury assessments. The level of family burden was high at both six and 30 months after injury, and was predicted by injury severity, functional impairment, and post injury child behavioural disturbance.

CONCLUSIONS

These results suggest ongoing problems for the child and significant family burden 30 months after TBI. The nature and severity of the physical and cognitive problems are closely related to injury severity, with child and family function predicted by psychosocial and premorbid factors.

The deaf mouse mutant Jeff (Jf) is a single gene model of otitis media

Otitis media is the most common cause of hearing impairment in children and is primarily characterized by inflammation of the middle ear mucosa. Yet nothing is known of the underlying genetic pathways predisposing to otitis media in the human population. Increasingly, large-scale mouse mutagenesis programs have undertaken systematic and genome-wide efforts to recover large numbers of novel mutations affecting a diverse array of phenotypic areas involved with genetic disease including deafness. As part of the UK mutagenesis program, we have identified a novel deaf mouse mutant, Jeff (Jf). Jeff maps to the distal region of mouse chromosome 17 and presents with fluid and pus in the middle ear cavity. Jeff mutants are 21% smaller than wild-type littermates, have a mild craniofacial abnormality, and have elevated hearing thresholds. Middle ear epithelia of Jeff mice show evidence of a chronic proliferative otitis media. The Jeff mutant should prove valuable in elucidating the underlying genetic pathways predisposing to otitis media.

Renal and cardiovascular considerations for the nonpharmacological and pharmacological therapies of obesity-hypertension

Obesity-associated hypertension is a common disease that involves a complex pathogenesis. Failure to control hypertension (HTN) in obese subjects provides a great threat to their renal and cardiovascular functions. The treatment of obesity-associated HTN is often difficult, and requires nonpharmacological and/or pharmacological approaches. Weight reduction is the cornerstone of the therapies of obesity-HTN, as it reverses the multiple components of its pathogenesis. When weight loss cannot be sustained or fails, pharmacological means should then be used. Angiotensin-converting enzyme inhibitors (ACEI) are the drug of choice: they can reduce blood pressure, protect the kidney and heart, and improve the metabolic abnormalities in obese subjects. Angiotensin-2 type-1 receptor blockers have a renoprotective benefit similar to ACEI, and they provide an important alternative to the use of ACEI. Diuretics are very effective in African-American obese hypertensives, but small doses should be used to avoid adverse effects on metabolic profiles. Long-acting calcium channel blockers are also effective and have the advantage of no adverse metabolic effects. Nondihydropyridine calcium channel blockers may provide additional renal and cardiovascular protective effects. The beta-adrenergic receptor blockers can cause further weight gain and metabolic abnormalities in obese subjects; therefore, careful monitoring is needed. There are few clinical data that support the efficacy and benefit of centrally acting alpha-2 agonists and alpha-adrenergic receptor antagonists in the treatment of obesity-HTN.

Outcome from mild head injury in young children: a prospective study

There is a lack of agreement regarding the long-term consequences of mild head injury (HI) at any age, with such effects rarely studied in early childhood. Given the rapid development occurring within the brain during this period, any disruption may have the potential to cause transient or permanent damage to brain structure and function. The present study sought to investigate the behavioral implications of such potential disruptions using a prospective, longitudinal design. Children aged 3-7 years at the time of injury, and suffering from mild HI, were evaluated acutely and at 6 and 30 months post-injury. Pre-injury data were collected with respect to communication, social skills, daily living skills and behavioral function. Results were compared to those from a non-injured control sample matched for age, gender, socioeconomic status, and pre-injury function. Findings showed few group differences. Children with mild HI performed similarly to controls on measures of intellectual ability, receptive language, and both everyday and spatial memory capacity. Group differences were identified for verbal fluency and story recall, with HI children failing to recover over time.

Four casein kinase I isoforms are differentially partitioned between nucleus and cytoplasm

The casein kinase I (CKI) family consists of at least seven vertebrate genes, some of which can be alternatively spliced. Previously, we have studied the four splice variants of the chicken CKIalpha gene. The four proteins differ only by the presence or absence of two peptides, a 28-amino-acid "L" insert in the catalytic domain and a 12-amino-acid "S" insert near the extreme C-terminus. Here cells were transfected with DNA encoding all four isoforms fused to the green fluorescent protein (GFP) and the localization of each protein was examined. We noted that the L insert includes the sequence PVGKRKR, which has the characteristics of a nuclear localization signal (NLS), and we show that the CKIalphaL and CKIalphaLS isoforms which contain this sequence are targeted to the nucleus, where a fraction becomes associated with nuclear speckles. In contrast the two isoforms lacking the L insert remain predominantly cytoplasmic. Mutation of the first lysine in the putative NLS to asparagine prevented the nuclear entry of GFP-CKIalphaL. Therefore different CKIalpha isoforms are targeted to different cellular compartments in a fashion modulated by alternate transcription and in these locations presumably phosphorylate and regulate different cellular substrates.

Molecular subtyping of Treponema pallidum in an Arizona County with increasing syphilis morbidity: use of specimens from ulcers and blood

A molecular-based subtyping system for Treponema pallidum was used during an investigation of increasing syphilis in Maricopa County, Arizona. Genital ulcer or whole blood specimens from patients with syphilis were assayed by a polymerase chain reaction (PCR) amplification of a T. pallidum DNA polymerase I gene. Positive specimens were typed on the basis of PCR amplification of 2 variable genes. In all, 41 (93%) of 44 of ulcer specimens and 4 (27%) of 15 blood specimens yielded typeable T. pallidum DNA. Twenty-four (53%) of 45 specimens were subtype 14f; other subtypes identified included 4f, 4i, 5f, 12a, 12f, 14a, 14d, 14e, and 14i. Only 2 specimens were from epidemiologically linked patients. This investigation demonstrates that multiple subtypes of T. pallidum can be found in an area with high syphilis morbidity, although 1 subtype (14f) was predominant. Four typeable specimens were from blood, a newly identified specimen source for subtyping.

Expression of a novel mammalian epidermal growth factor-related gene during mouse neural development

We have recently reported the preliminary characterisation of a novel EGF-related gene, Scube1 (signal peptide-CUB domain-EGF-related, gene 1), that is expressed prominently in the developing gonad, nervous system, somites, surface ectoderm and limb buds of the mouse. Here we describe the expression pattern of a closely related gene, Scube2 (also known as Cegp1), which maps to the distal region of mouse chromosome 7. Scube2 transcription is restricted to the embryonic neurectoderm but is also detectable in the adult heart, lung and testis.

Predictors of acute child and family outcome following traumatic brain injury in children

OBJECTIVE

To examine the relative contributions of injury severity, level of physical and cognitive disability, child behavior and family function to short-term outcome 6 months following traumatic brain injury (TBI) in children.

DESIGN

Prospective, longitudinal, between-group design, comparing preinjury and postinjury measures of functional outcome across three levels of injury severity.

SUBJECTS

One hundred and twelve children, aged 2-12 years admitted to the Royal Children's Hospital, Melbourne, with a diagnosis of TBI. The sample was divided into three groups, according to injury severity: mild TBI (n = 31), moderate TBI (n = 52) and severe TBI (n = 29). Children with a history of neurologic, developmental and psychiatric disorder were excluded from participation.

MAIN OUTCOME MEASURES

Levels of postinjury functioning in the following domains: physical function, cognitive ability (incorporating intellect, memory and attention), behavioral and family functioning, and level of family burden.

RESULTS

A clear dose-response relationship for physical and cognitive outcomes was found, with severe TBI associated with greater impairment of physical, intellectual, memory and attentional function. For psychosocial outcome, results were less clearly linked to injury severity. Preinjury behavioral and family functioning were closely related to postinjury function in these domains, with an interaction identified between family function and child behavior at 6 months postinjury. Family functioning remained unchanged postinjury, although level of burden was high, and predicted by injury severity, functional impairment and postinjury behavioral disturbance.

CONCLUSIONS

These results suggest ongoing functional problems for the child and significant family burden 6 months following TBI. The nature and severity of physical and cognitive problems are most closely related to injury severity, with family functioning and child behavior better predicted by psychosocial and premorbid factors.

Recovery of intellectual ability following traumatic brain injury in childhood: impact of injury severity and age at injury

Traumatic brain injury (TBI) may have a profound impact on a child's ongoing development. Various risk factors have been found to predict outcome, but considerable variability remains unexplained. This study used a prospective, longitudinal design to examine the relationship between recovery, injury severity, age at injury and pre-injury ability. 124 children were divided according to (1) age at injury: 'young' (3-7 years) 'old' (8-12) and (2) injury severity (mild, moderate, severe). Children were evaluated acutely (T1) and at 12 months post-injury (T2), using standardized intellectual measures (IQ). Results showed a relationship between greater injury severity and poorer IQ. Age at injury was not predictive of outcome for children with mild/moderate TBI. For severe TBI, younger age at injury led to minimal recovery in IQ, while recovery from later injury was similar to that for adults. Findings suggest that children sustaining severe TBI in early childhood may be particularly at risk for residual problems post-injury.

Development of a serological test for Haemophilus ducreyi for seroprevalence studies

We developed a new enzyme immunoassay (rpEIA) for use in determining the seroprevalence of chancroid. Three highly conserved outer membrane proteins from Haemophilus ducreyi strain 35000 were cloned, overexpressed, and purified from Escherichia coli for use as antigens in the rpEIA. Serum specimens from patients with and without chancroid were assayed to determine optimum sensitivity and specificity and to establish cutoff values. On the basis of these data, rpEIA was found to be both sensitive and specific when used to test a variety of serum specimens from patients with genital ulcers and urethritis and from healthy blood donors.

Early effects of traumatic brain injury on young children's language performance: a preliminary linguistic analysis

Language skills undergo rapid development during the early childhood years, so that by the time children start school they are competent communicators with well established syntactic, semantic and pragmatic abilities for their age. Little is known about the effects of traumatic brain injury (TBI) on the acquisition of these language skills during the early childhood years. This study used a prospective, cross-sectional design to compare the language abilities of young children following their head injury. Fifteen brain injured children, aged between 4-6 years, were divided into three injury groups depending on severity of injury, i.e. mild, moderate and severe, and compared with a matched community control group. They were assessed within 3 months of sustaining their injury on a range of expressive and receptive language tests, and free speech conversation samples, which were analysed pragmatically and syntactically. Results indicated that the severe group performed most poorly on language tasks. It is suggested that linguistic evaluation is an important component of follow up at least for the severe head injured population.

Newly available and future laboratory tests for sexually transmitted diseases (STDs) other than HIV

BACKGROUND AND OBJECTIVES

The development and introduction of nucleic acid amplification (NAA) tests by commercial sources has improved our ability to diagnose chlamydial infections and other sexually transmitted diseases (STDs). A review of approaches to diagnosing STDs can provide a clearer picture of the present needs.

GOALS

To review the advantage and disadvantages of current and future diagnostic approaches.

STUDY DESIGN

Survey the literature and define current and future needs in developed and developing country settings.

RESULTS

The increase in analytical sensitivity afforded by NAA has enabled the use of noninvasive specimens, such as first-void urine (FVU) and self-obtained vaginal swabs, for diagnostic testing and screening asymptomatic low-prevalence populations and hard-to-access populations. This technology allows multiplexing in which targets from multiple agents responsible for a particular syndrome can be amplified and detected. Although NAA tests have been designed to minimize contamination, there is some reluctance to replace less sensitive tests with this new technology. The concerns involve potential false positive and false negative results caused by the presence of inhibitors, even though the rates of false results are low. Other concerns are cost, through-put, hands-on time, and time necessary for results.

CONCLUSIONS

Nucleic acid amplification tests are a great improvement and additional tests are needed for the diagnosis of STDs at the point of first encounter, with minimal delay between diagnosis and treatment. Affordable tests, which are rapid, sensitive, and specific are needed for use in resource-limited settings where most STDs are seen; this has been a major undertaking for the Sexually Transmitted Diseases Diagnostics Initiative.

Aetiology of yam (Dioscorea rotundata) tuber rots held in traditional stores in Nigeria: importance of Fusarium spp. and yam beetle

The extent and causes of yam (Dioscorea rotundata) tuber rots were investigated in Igalaland, Nigeria. Rots were found to be associated with prior physical damage in almost all cases. Numerous fungal species were isolated from the infected lesions of which Fusarium spp. predominated, not Botrydiplodia theobromae as previously reported in other studies. None of the fungi was able to infect undamaged yams in laboratory experiments. The damage was caused by both biotic and abiotic factors of which the yam beetle (Heteroligus meles) was the largest single cause. There were significant differences in the frequency with which different varieties of yam were attacked by H. meles and found to be infected with Fusarium spp. In an independent survey of farmers' experience of yam rots, varieties that scored well correlated with apparent resistance to the beetle and Fusarium spp. These studies highlight the importance of yam beetle infestation and the need to have independent methods for varietal authentication.

Pelvic inflammatory disease isolates of Neisseria gonorrhoeae are distinguished by C1q-dependent virulence for newborn rats and by the sac-4 region

The virulence mechanism of Neisseria gonorrhoeae in pelvic inflammatory disease (PID) is not well understood, and an objective diagnostic method to identify patients with PID is lacking. We investigated the hypothesis that development of PID was associated with a C1q-dependent virulence property of gonococcal strains. Recent development of a C1q-dependent experimental model of gonococcal infection (S. Nowicki, M. Martens, and B. Nowicki, Infect. Immun. 63:4790-4794, 1995) created an opportunity to evaluate this hypothesis in vivo. Therefore, the virulence of 32 clinical isolates (18 PID isolates and 14 local infection [LI] isolates) was evaluated in experimental rat pups. A serum bactericidal assay was used to characterize a gonococcal serum-resistant (ser(r)) phenotype. PCR primers designed to amplify a suitable-size gonococcal sac-4 DNA fragment (unique for serum-resistant donor JC1) were used to evaluate the association of serum-resistant genotype sac-4 with two phenotypes: C1q-dependent virulence expressed in vivo and resistance to bactericidal activity of human serum expressed in vitro. Strains were also characterized by auxotyping and serotyping. Of 32 gonococcal strains, 15 (46.7%) caused C1q-dependent bacteremia in rat pups and were sac-4 positive and ser(r). However, of the 15 isolates, 13 (87%) represented strains associated with human PID and 2 (13%) were associated with LI. None of the strains that were completely serum-sensitive (ser(s)) and sac-4 negative produced C1q-dependent bacteremia in rat pups, suggesting that both ser(r) and sac-4 were required for infection. The serum-resistant recombinant recipient of sac-4 produced C1q-dependent bacteremia in the rat model similarly to the serum-resistant donor of sac-4; the serum-sensitive parent strain did not produce bacteremia. These data suggest that sac-4-mediated serum resistance conferred C1q-dependent virulence and is a unique characteristic associated with PID. These newly identified features may contribute to the understanding of the pathogenic mechanism of PID-associated strains and open perspectives for establishing novel diagnostic methods.

Hepatitis B virus infection in high-risk inner-city neighborhoods in San Francisco

To examine the extent of hepatitis B virus infection (HBV) in an inner-city community, we determined the prevalence, incidence, and correlates of HBV seroreactivity in a representative sample of unmarried whites, African-Americans, and Hispanics living in San Francisco during 1988 to 1989 and again 1 year later in 1989 to 1990. Unmarried men and women aged 20 to 44 years were surveyed in a random household sample drawn from three neighborhoods of varying geographic and cultural characteristics. Hepatitis B infection was determined by testing specimens for antibody to hepatitis B core antigen (anti-HBc). Of blood samples available from 1,108 participants from the initial survey, 159 (14%) were anti-HBc positive. There was a strong positive association between anti-HBc positivity and positive serological tests for human immunodeficiency virus, herpes virus type 2, and syphilis. In women and heterosexual men, after controlling for other variables, anti-HBc positivity was significantly associated with older age (P < .001), nonwhite ethnicity (P < .01), less education (P < .05), injection drug use (P < .001), being paid for sex (P < .05), and lifetime number of sexual partners (P < .05). Among homosexually active men, after controlling for other variables, anti-HBc positivity was significantly associated with nonwhite ethnicity (P < .001), injection drug use in a sexual partner (P < .05), and number of lifetime sexual partners (P < .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence, incidence, and correlates of syphilis seroreactivity in multiethnic San Francisco neighborhoods

To examine the extent of infection with syphilis in an inner-city community, we determined the prevalence, incidence, and correlates of syphilis seroreactivity in a representative sample of unmarried whites, African Americans, and Hispanics living in San Francisco during 1988 to 1989 and again 1 year later in 1989 to 1990. One thousand seven hundred seventy single men and women aged 20 to 44 were surveyed in a random household sample drawn from three neighborhoods of varying geographic and cultural characteristics. Syphilitic infection was determined by testing specimens with the microhemagglutination assay for antibodies to Treponema pallidum (MHA-TP). Of blood samples available from 1262 participants from the initial survey, 32 (2.5%) were MHA-TP reactive. After adjustment for age, a reactive syphilis serology was significantly predicted (P < 0.05) by African American race, homosexual activity (men), and less education. In homosexually active men, lifetime number of male sex partners and the presence of antibody to the human immunodeficiency virus (HIV) significantly predicted syphilis seroreactivity (P < 0.01). One year later, of 841 specimens available for testing, an additional 13 (1.5%) had become MHA-TP reactive. Eleven (85%) of the new cases were in heterosexual men and women. Although San Francisco citywide incidence data indicate that syphilis may be decreasing for the city as a whole, incidence data on a community level suggests that syphilitic infection is increasing in high-risk heterosexual communities. Thus, syphilis prevention programs should rely on serologic testing at the community level to plan effective intervention strategies.

Genetic diversity of the iron-binding protein (Fbp) gene of the pathogenic and commensal Neisseria

The pathogenic Neisseria and most commensal Neisseria species produce an iron-binding protein (Fbp) when grown under iron-limited conditions. In the current study, we confirmed the presence of Fbp, as well as DNA sequences homologous to the gonococcal fbp, in strains of N. gonorrhoeae, N. meningitidis, N. cinerea, N. lactamica, N. subflava, N. kochii and N. polysaccharea. The fbp genes from these strains were amplified by the polymerase chain reaction, digested with StuI or RsaI, and the restriction patterns examined. The patterns for the gonococcal and meningococcal fbp were virtually identical; however, variations were observed in the fbp sequences of the commensal Neisseria species. N. flavescens, N. mucosa, N. sicca, N. ovis and Branhamella catarrhalis, did not produce Fbp as detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and reactivity with an Fbp specific monoclonal antibody, nor did they hybridize to an fbp-specific DNA probe.

Acquired immunodeficiency without evidence of infection with human immunodeficiency virus types 1 and 2

There have been three published cases of acquired immunodeficiency in which no evidence for infection with human immunodeficiency virus (HIV) types 1 and 2 was found. We have identified five other individuals, from the New York City area (four who have known risk factors for HIV infection), with profound CD4 depletion and clinical syndromes consistent with definitions of the acquired immunodeficiency syndrome (AIDS) or AIDS-related complex. None had evidence of HIV-1, 2 infection, as judged by multiple serologies over several years, standard viral co-cultures for HIV p24 Gag antigen, and proviral DNA amplification by polymerase chain reaction.

Giant colonic mucocele following palliative surgery for recurrent squamous cell carcinoma of the cervix

We report an unusual complication following palliative surgery in a patient with carcinomatosis peritonei from recurrent squamous cell carcinoma of the cervix. At surgery the ascending colon was bypassed and isolated. Eight months later the patient presented with a giant mucocele. We believe this to be the first reported case in the gynecologic literature. This complication could have been prevented by adhering to the standard surgical management of fashioning a mucous fistula.

Fluoxetine ingestion: a one year retrospective study

Fluoxetine (PROZAC) is a recently marketed straight chain antidepressant unrelated to the cyclic anti-depressants. There is only limited information on fluoxetine and a single case report on overdose (benign outcome) in the literature. In response to this we performed a 1y retrospective chart review at 2 AAPCC certified poison centers. Forty-four exposures to fluoxetine were reviewed from 1988; 31 cases were treated in a HCF, 2 cases were followed at home by phone and 11 cases were lost to follow up. Thirteen cases with follow up (FU) reported no coingestants; 3 cases reported increased anxiety without cardiovascular (CV) changes, 2 cases presented confused with out CV changes, and 8 cases were asymptomatic. Eight cases with FU had ETOH and/or benzodiazepines as a coingestant and experienced only a decreased level of consciousness that could be explained by the coingestant. Five cases remained asymptomatic with reported coingestants of APAP #3, lorazepam, haloperidol, molindone, alprazolam, propranolol, phenobarbital (level 18.2). Four cases were excluded from the evaluation due to the coingestants involved. No seizures were recorded in this series. Three possible drug reactions occurred; 2 cases had reactions with tranylcypromine (PARNATE), and 1 case with a diagnosis of septicemia had a severe hyperthermic reaction with therapeutic coingestants of mephytoin, verapamil, digoxin and indocin. We believe overdose with fluoxetine present minimal risk of serious cardiovascular or neurological complications.

Complement activity and selected hematologic variables in newborn foals fed bovine colostrum

Serum complement activity and selected hematologic variables were evaluated in 5 newborn foals fed bovine colostrum (principal group) and 6 foals allowed to nurse their dam (control group). Also, bovine colostrum was evaluated for anti-equine antibodies. Precolostral serum hemolytic and conglutinating complement activities were low and increased similarly in foals of both groups to reach adult values between 1 and 3 weeks after birth. Bovine colostrum strongly agglutinated, but did not hemolyse principal foals' RBC and blood containing all known equine blood group alloantigens. Hemolysis was not detected after administration of bovine colostrum. Physiologic anemia developed in foals of principal and control groups during the first week of life. Erythrocyte osmotic fragility in foals of the principal group prior to and after the ingestion of colostrum remained unchanged. However, at 36 hours after birth, there was a significant decrease in erythrocyte osmotic fragility in foals fed homologous colostrum.

Hemodynamic evaluation of isosorbide dinitrate in alcoholic cirrhosis. Pharmacokinetic-hemodynamic interactions

Isosorbide dinitrate, a long-acting organic nitrate, has been shown to decrease portal pressure in the experimental animal and humans. We conducted a double-blind randomized hemodynamic evaluation of the effects of placebo and 10 mg and 20 mg isosorbide dinitrate in stable individuals with alcoholic cirrhosis. Baseline values for all three groups were similar. Isosorbide dinitrate resulted in a peak reduction of the hepatic venous gradient of 24.7% +/- 3.0%, with significantly decreased values 4 h after the administration of the 20-mg dose. A reduction of arterial pressure and cardiac index (peak decrease of 25.7% +/- 1.5%) was well tolerated by 13 of 15 patients. Changes in mean arterial pressure were not predictive of modifications in the hepatic vein wedge pressure. There was no relation between the area under the plasma isosorbide dinitrate concentration curve and hemodynamic changes. Levels of isosorbide-5-mononitrate, a vasoactive metabolite, were detectable for an 8-h period. Isosorbide dinitrate significantly reduced portal pressure in stable cirrhotics, in association with systemic hemodynamic changes. Thus, titration of isosorbide dinitrate is required to maximize hemodynamic benefits in individual patients. As the decrease in portal pressure is more predictable than the effect of previously tested pharmacologic agents, isosorbide dinitrate should be evaluated for its efficacy in the management of portal hypertension.

Acute dissection originating in the abdominal aorta

A primary abdominal aortic dissection was encountered in a 53-year-old hypertensive man who was admitted with a 2-week history of back pain. Treatment with an infrarenal aortic bifurcation graft complemented by reconstruction of the proximal aortic cuff was curative.