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Biogeochemical cycling of sulfur is relatively understudied in terrestrial environments compared to marine environments. However, the comparative ease of access, observation, and sampling of terrestrial settings can expand our understanding of organisms and processes important in the modern sulfur cycle. Furthermore, these sites may allow for the discovery of useful process analogs for ancient sulfur-metabolizing microbial communities at times in Earth's past when atmospheric O2 concentrations were lower and sulfide was more prevalent in Earth surface environments. We identified a new site at Santa Paula Creek (SPC) in Ventura County, CA—a remarkable freshwater, gravel-bedded mountain stream charged with a range of oxidized and reduced sulfur species and heavy hydrocarbons from the emergence of subsurface fluids within the underlying sulfur- and organic-rich Miocene-age Monterey Formation. SPC hosts a suite of morphologically distinct microbial biofacies that form in association with the naturally occurring hydrocarbon seeps and sulfur springs. We characterized the geology, stream geochemistry, and microbial facies and diversity of the Santa Paula Creek ecosystem. Using geochemical analyses and 16S rRNA gene sequencing, we found that SPC supports a dynamic sulfur cycle that is largely driven by sulfide-oxidizing microbial taxa, with contributions from smaller populations of sulfate-reducing and sulfur-disproportionating taxa. This preliminary characterization of SPC revealed an intriguing site in which to study geological and geochemical controls on microbial community composition and to expand our understanding of sulfur cycling in terrestrial environments.

S-Adenosyl-l-methionine (AdoMet) is an essential enzyme cosubstrate in fundamental biology with an expanding range of biocatalytic and therapeutic applications. In recent years, technologies enabling the synthesis and utilization of novel functional AdoMet surrogates have rapidly advanced. Developments highlighted within this brief review include improved syntheses of AdoMet analogs, unique S-adenosyl-l-methionine isosteres with enhanced stability, and corresponding applications in epigenetics, proteomics and natural product/small molecule diversification (‘alkylrandomization‘).

Persistently low atmospheric oxygen requires that net organic carbon burial was muted through much of Earth’s middle age. In order to achieve global mass balance with respect to O2, recent models have suggested that redox-dependent mechanisms, such as Fe(II)-phosphate precipitation, limited phosphate availability in dominantly anoxic and ferruginous oceans, in turn limiting net primary production, and therefore organic carbon burial. Nevertheless, observational constraints on phosphorus cycling in ferruginous Proterozoic systems are rare, leaving these models largely untested. Here, we present high-resolution petrographic and mineralogical data showing that the 1.3 Ga Sherwin Ironstone (Roper Group, Australia) was dominated by syndepositional precipitation of the Fe(II)-silicate minerals greenalite and berthierine, interlaminated with abundant authigenic calcium fluorapatite (CFA). Set in a quantitative geochemical framework, these data reveal that elevated marine SiO2(aq) concentrations facilitated extensive Fe(II)-silicate production, leaving CFA, rather than Fe(II)-phosphate, as the principal inorganic phosphorous sink in shallow-water Roper Group sediments. More broadly, the physical and chemical factors that triggered Fe(II)-silicate and CFA burial in the Roper Seaway highlight semi-restricted basins as important loci of phosphorus removal from the mid-Proterozoic ocean.

Aminoglycosides (AGs) are clinically relevant antibiotics used to treat infections caused by both Gram-negative and Gram-positive bacteria, as well as Mycobacteria . As with all current antibacterial agents, resistance to AGs is an increasing problem. The most common mechanism of resistance to AGs is the presence of AG-modifying enzymes (AMEs) in bacterial cells, with AG acetyltransferases (AACs) being the most prevalent. Recently, it was discovered that Zn 2+ metal ions displayed an inhibitory effect on the resistance enzyme AAC(6′)-Ib in Acinetobacter baumannii and Escherichia coli . In this study, we explore a wide array of metal salts (Mg 2+ , Cr 3+ , Cr 6+ , Mn 2+ , Co 2+ , Ni 2+ , Cu 2+ , Zn 2+ , Cd 2+ , and Au 3+ with different counter ions) and their inhibitory effect on a large repertoire of AACs [AAC(2′)-Ic, AAC(3)-Ia, AAC(3)-Ib, AAC(3)-IV, AAC(6′)-Ib′, AAC(6′)-Ie, AAC(6′)-IId, and Eis]. In addition, we determine the MIC values for amikacin and tobramycin in combination with a zinc pyrithione complex in clinical isolates of various bacterial strains (two strains of A. baumannii , three of Enterobacter cloacae , and four of Klebsiella pneumoniae ) and one representative of each species purchased from the American Type Culture Collection.

S-adenosyl-l-methionine (AdoMet) is an essential enzyme cosubstrate in fundamental biology with an expanding range of biocatalytic and therapeutic applications. We report the design, synthesis, and evaluation of stable, functional AdoMet isosteres that are resistant to the primary contributors to AdoMet degradation (depurination, intramolecular cyclization, and sulfonium epimerization). Corresponding biochemical and structural studies demonstrate the AdoMet surrogates to serve as competent enzyme cosubstrates and to bind a prototypical class I model methyltransferase (DnrK) in a manner nearly identical to AdoMet. Given this conservation in function and molecular recognition, the isosteres presented are anticipated to serve as useful surrogates in other AdoMet-dependent processes and may also be resistant to, and/or potentially even inhibit, other therapeutically relevant AdoMet-dependent metabolic transformations (such as the validated drug target AdoMet decarboxylase). This work also highlights the ability of the prototypical class I model methyltransferase DnrK to accept non-native surrogate acceptors as an enabling feature of a new high-throughput methyltransferase assay.

Despite remarkable progress over the past several decades in understanding the biology and epidemiology of the HIV pandemic the virus continues to spread relentlessly. Diverse prevention approaches are desperately needed to reverse this trend. For many women products that can be used without the cooperation of male partners are critical. Multiple such products are currently being tested in large-scale effectiveness trials and many more are in earlier stages of development. These products include physical and chemical barriers to viral entry vaginal pH buffers an antiherpes drug antiretroviral drugs and other agents. Some of these products may have contraceptive as well as anti-infective activity. The basic design of HIV prevention trials is standard: HIV-negative women at risk for HIV infection are randomly assigned to use either the study product or a placebo according to a specified schedule (e.g. daily or before each coital act) and then are followed to assess HIV incidence. Most HIV prevention trials are conducted in resource-poor settings in Africa and Asia where HIV incidence is high. (excerpt)

The history of fertility regulation in Romania illustrates the complex interactions between politics, women's reproductive health and rights and access to high quality care. This paper describes the current situation of abortion and contraception in Romania, based on national statistics, recent reproductive health surveys and the findings of a strategic assessment led by the Ministry of Health in late 2001. This rapid assessment employed a participatory, qualitative methodology. Over 500 people were interviewed from 145 institutions in 25 cities, towns and villages in Romania, about the range of actions needed to prevent unwanted pregnancies, reduce abortion-related morbidity and mortality and improve the quality, accessibility and availability of abortion and contraceptive services. Although much progress has been made in contraceptive services over the past ten years, improvements in abortion care have lagged considerably. The assessment played an important role in raising team members' awareness and motivation to take action. Some of the issues identified are already being addressed by the institutions that took part. National standards and guidelines for comprehensive abortion care have been developed, contraceptive services have been expanded at primary health care level, sexual and reproductive health education provided by classroom teachers has been introduced in schools, and a study to test a model of comprehensive abortion care services for Romania is planned.

Abortion was made legal on request in Mongolia in 1989, following the collapse of the socialist regime, and later bound by a range of regulations. Concerned about the high number of abortions and inadequate quality of care in abortion services, the Ministry of Health applied the World Health Organization's Strategic Approach to issues related to abortion and contraception in 2003. The aim was to develop policies and programmes to reduce unintended pregnancies, mitigate complications from unsafe abortion, and improve the quality of abortion and contraception services for all socio-economic groups, including adolescents. This paper describes the changes that arose from a strategic assessment, highlighting the introduction of mifepristone-misoprostol for second trimester abortion. The aim was to replace mini-caesarean section and intra-uterine injection of Rivanol (ethacridine lactate), so that second trimester abortions could take place earlier than at 20 weeks gestation. Notional standards and guidelines for comprehensive abortion core were developed, the national pre-service training curriculum was harmonised with the new guidelines, at least one-third of the country's obstetrician-gynaecologists were trained in manual vacuum aspiration and medical abortion, and three model comprehensive abortion care units were established to provide high quality services to women, high quality training for providers and serve as nodes for further scaling up. (c) 2008 Reproductive Health Matters. All rights reserved.

To estimate and describe the magnitude of abortion complications presenting at public hospitals in Kenya.Cross-sectional descriptive study.Hospital-based. Population Records of all women presenting prior to 22 weeks of gestation with abortion-related complications at selected hospitals during a three-week study period. All public tertiary and provincial hospitals were included; stratified random sampling was employed to select a subset of 54 district hospitals nationwide.Data collectors identified 809 patients with abortion complications on all hospital wards and completed a standardised questionnaire for each by extracting information from the patient's hospital record.Incidence, aetiology, morbidity and mortality of abortion complications.Most women (80%) presented with incomplete abortion. Approximately 34% of the women had reached the second trimester of pregnancy. Adolescents (14-19 years old) accounted for approximately 16% of the study sample. Manual vacuum aspiration was used to manage 80% of first trimester cases. The projected annual number of women with abortion complications admitted to public hospitals in Kenya is 20,893. The case fatality rate was estimated to be 0.87% (95% CI 0.71-1.02%), so an estimated 182 (95% CI 148-213) of these women die annually. The annual incidence of incomplete abortion and other abortion-related complications per 1000 women aged 15 to 49 years is projected to be 3.03.The high rate of abortion-related morbidity and mortality documented in the study highlights the critical need to address the issue of unsafe abortion in Kenya.

Vietnam's family planning program got underway in the early 1960s. Since then, it has successfully encouraged the population to have smaller families. According to the 1997 Demographic and Health Survey, the total fertility rate 12 months before the survey was 2.37, down from 4.0 in 1988. Also, the use of modern contraceptive methods has increased from 38% of couples in 1988 to 56% in 1997. The program's major achievement has been in creating a demand for family planning. However, in the years ahead, the growing demand for family planning will challenge the national program. Improvements must therefore be made in the quality of reproductive health services in order to maintain the past success of the population program and to continue to meet the demand for reproductive health methods and services. A number of efforts have been launched to research and evaluate the quality of family planning services and policies related to the program. The Ministry of Health is collaborating with a number of national and international nongovernmental organizations to improve the quality and delivery of health services. Findings are presented from a study conducted during 1997-98 to assess client perspectives on the quality of reproductive health services.

In many countries, women treated for complications from spontaneous or unsafely induced abortion lack access to contraceptive services. As a result, many of them soon have a subsequent unplanned pregnancy or a repeat abortion, placing their health at increased risk. This report presents the results of a prospective intervention study on postabortion family planning conducted in the two largest public hospitals in Zimbabwe. Women at Harare Central Hospital, in the capital, received a postabortion family planning intervention, and Mpilo Central Hospital, in Bulawayo, served as the control site. The study cohort was 982 women, 527 of whom were followed for a 12-month period. During the follow-up period, significantly more women used highly effective methods of contraception, significantly fewer unplanned pregnancies occurred, and fewer repeat abortions were performed at the intervention site than at the control site. These results offer compelling evidence that ward-based contraceptive services provided to women treated for incomplete abortion can significantly reduce subsequent unplanned pregnancies. The results also suggest that postabortion family planning services can reduce the incidence of repeat abortion.

Romanian women have commonly used abortion (both legal and clandestine) to prevent unwanted births. We introduce this paper with a brief summary of the recent history of abortion in Romania, then we combine quantitative data from a previous report ([1] Johnson et al., Lancet 341, 875, 1993) of the research with women's own words about the following issues: their decisions to have an abortion, the impact of abortion restrictions under the Ceausescu government, and their needs and desires for improved reproductive health services. We also present gynaecologists' views of abortion restrictions and needs for improved family-planning services to make a compelling case for the need for safe, legal, comprehensive abortion care in Romania and elsewhere.

In much of the developing world, sharp curettage (SC) is the most commonly used technique for treating incomplete abortion. The procedure is usually performed in a hospital setting where physicians and operating theatres are available; it often involves light to heavy sedation for pain control and an overnight hospital stay for patient recuperation and monitoring. This study examined the hypothesis that use of manual vacuum aspiration (MVA)—a variation of vacuum aspiration (VA)—would be less costly than SC and thus be advantageous to healthcare systems with limited resources. The purpose of the study was to identify and, where possible, to explain the factors that contributed to cost differences between MVA and SC for treatment of incomplete abortion. To achieve this objective, researchers observed patient management and documented resource use at hospital sites in Kenya and Mexico. The results of the study support the researchers' hypothesis that, in most cases, treatment with MVA required a shorter patient stay and fewer hospital resources than SC, as the two techniques were practiced at the various study sites. The policy decision to adopt MVA, supported by procurement of instruments and incorporation of training in its use, is the basic prerequisite to achieving reduced levels of resource use. The study results also suggest that the full advantages of MVA can be realized only if it is introduced in conjunction with certain changes in patient management, such as offering outpatient treatment for incomplete abortion.

After the downfall of the Ceausescu regime in December, 1989, the new Government of Romania abolished the law that prohibited abortions on request. Subsequently, the rate of legally induced abortions increased significantly while the rate of maternal mortality declined dramatically. Despite the large number of women who request induced abortions, most women and gynaecologists say that they would prefer to prevent unwanted pregnancies through the use of modern contraception. In this paper we examine factors that contribute to the disparity between women's desire to use modern contraception to prevent unwanted pregnancies and their practice of having induced abortions to prevent unwanted births. The results show that women (and suggest that men) need a wide choice of dependably available high-quality contraceptives; they need to be able to obtain information, counselling, and methods from a wide range of sources/health-care providers; both women's and men's perceptions about, and use of, modern contraception could be positively affected through sexual education started in secondary school; and, to reduce repeat abortions, women's post-abortion family-planning needs must not be neglected.The factors that contribute to the disparity between women's desire to use modern contraception and the practice of induced abortions to prevent unwanted births are examined. Structured interviews of 1000 women were conducted in 5 hospitals located in 3 culturally different regions of Romania--Bucharest, Moldova (2 sites), and Transylvania (2 sites). All data were collected between November 1991 and April 1992. At each site structured interviews were conducted over 4-6 weeks with a random sample of 200 women who were either waiting for or recovering from an induced abortion, and 80 semi-structured client interviews were conducted among the 5 sites. There were 35 semi-structured provider interviews in the 5 sites, and one group interview was conducted with clients and one with providers of abortion services in each location. In 1991 there were 789,096 reported legal abortions compared with about 275,000 live births. 47% of the women said that they had had a previous legally induced abortion and 25% reported a previous illegal abortion. 31% of the women said that they would have an illegal abortion if they were unable to have one legally. The choice of contraceptive methods was often limited to 1 type available (condoms or Depo Provera). Women and gynecologists reported that modern contraceptive methods are rarely available from pharmacies. Some contraceptive services were available in most hospitals, but women had to take the initiative. 69% of gynecologists responded that women who want information about contraception wait for the gynecologist to offer it. 72% of the women thought that other women gave gifts to the gynecologist who performed their abortion; 39% did not think a gift would ensure better treatment and enthusiasm to counsel women about contraception. Many women and most gynecologists believed that sexual and contraceptive educations should begin early in the schools involving both sexes. 52% of clients and 75% of providers said that sexual and contraceptive education should begin in secondary schools.

Tests of hand grip strength and hand grip muscle fatigue were conducted on Ngisonyoka Turkana pastoralists of northwest Kenya to explore some of the functional relationships between activity and body composition. The test of maximal voluntary contraction (MVC) of hand grip flexors was conducted on 151 Turkana and 38 U.S. men and women. The fatigue test was conducted on the same number of subjects who were instructed to attempt to maintain 80% of the MVC for 90 seconds. The results of these tests, combined with arm measurements of size and body composition, were used to evaluate muscle size and strength relationships and to estimate muscle fiber type distribution in the forearm. MVC values of Turkana men were low by U.S. and European standards. The low values resulted from smaller Turkana muscle areas. MVC values of Turkana women were comparable to those of U.S. and European women, reflecting comparable muscle areas. The fatigue curves of Turkana and U.S. men and women suggest that slow-twitch aerobic muscle fibers predominate for the hand grip flexors of the Turkana pastoralists.