Heavy metal pollution in selected upland tributaries of Sri Lanka: comprehension towards the localization of sources of pollution.

This study aimed to assess the heavy metal (HM) profile of the main upland tributaries of three major rivers, the Mahaweli, the Deduru and the Gin Rivers, which are commonly used for urban water supply in Sri Lanka. The HM profiles of arsenic (As), cadmium (Cd), lead (Pb) and mercury (Hg) were investigated by ICP-MS. Land-use classification was performed to locate the main sources of pollution. Mean pH, TDS and conductivity showed significant inter-site mean differences (p < 0.001). The mean contents of the HMs, considering all rivers, were observed in the order [Hg] > [As] > [Pb] > [Cd] at the sources and [As] > [Hg] > [Pb] > [Cd] at the river mouths. Particularly, in the Mahaweli River, the mean As content was 0.08 ± 0.05 µg·L-1 and showed an increasing trend from the source to the river mouth. In the Deduru River, the mean Hg content was 0.14 ± 0.15 µg·L-1, and of all rivers studied, the highest content of 0.50 ± 0.17 µg·L-1 was recorded. The Gin River showed significant inter-site mean differences (p < 0.05) in [Pb], [As] and [Hg]. In all rivers studied, [As] was significantly higher in water samples collected near agricultural lands and urban areas as compared with the other land-use/cover types, which was further proved by a significant positive correlation (coefficient = 0.479, p = 0.0325). We, therefore, emphasized that HM pollution is more likely due to anthropogenic activities in the upper catchment with less lithogenic contamination. However, national water quality management should be further strengthened and new policy enforcement is emphasized.

Cervical dilatation and preparation prior to outpatient hysteroscopy: a systematic review and meta-analysis.

BACKGROUND: There are uncertainties about the benefit of routine cervical preparation and/or cervical dilatation before outpatient hysteroscopy. OBJECTIVE: To determine if cervical preparation and/or routine mechanical dilatation reduces pain during outpatient hysteroscopy. SEARCH STRATEGY: MEDLINE, EMBASE, CINAHL and CENTRAL were searched on 19 October 2020, using keywords 'hysteroscopy', 'cervical preparation', 'cervical ripening', 'cervical dilatation', 'outpatient', 'office' and/or 'ambulatory' and associated medical subject headings. SELECTION CRITERIA: Randomised controlled trials investigating the benefit of cervical preparation and/or cervical dilatation on pain in women undergoing outpatient hysteroscopy were included. DATA COLLECTION AND ANALYSIS: Two independent reviewers selected eligible trials and extracted data on pain, feasibility, adverse events and satisfaction/acceptability for meta-analysis. MAIN RESULTS: The literature search yielded 807 records, of which 24 were included for review and 19 provided data for meta-analysis. No trials investigated the role of routine mechanical cervical dilatation. Cervical preparation significantly reduced pain during outpatient hysteroscopy; standard mean difference (SMD) -0.67, 95% confidence interval (CI) -1.05 to -0.29. Feasibility also improved as priming provided significantly easier hysteroscopic entry (SMD 0.89, 95% CI 0.32-1.46), greater cervical dilatation (SMD 0.81, 95% CI 0.08-1.53) and shorter procedural times (SMD -0.51, 95% CI -0.88 to -0.13). Cervical preparation, however, incurred significantly more adverse effects, mainly comprising genital tract bleeding, abdominal pain and gastrointestinal symptoms (odds ratio 2.94, 95% CI 1.58-5.47). There were limited data regarding satisfaction, acceptability and complications. CONCLUSIONS: Cervical preparation reduces pain and improves feasibility associated with outpatient hysteroscopy but increases the risk of adverse effects. TWEETABLE ABSTRACT: Cervical preparation before outpatient hysteroscopy reduces pain, enhances feasibility but increases adverse effects.

Fallopian tube catheterization in the treatment of proximal tubal obstruction: a systematic review and meta-analysis.

Study question: What is the chance of clinical pregnancy when fallopian tube catheterization is used for proximal tubal obstruction? Summary answer: The pooled clinical pregnancy rate of tubal catheterization after proximal tubal obstruction is 27% (95% CI 25-30%). What is known already: Restoring fallopian tube patency by performing tubal catheterization has fallen out of favour since the increased availability of IVF. Our study is the first systematic review and meta-analysis to investigate reproductive outcomes following tubal catheterization for proximal tubal obstruction. Study design, size, duration: We undertook a systematic review and meta-analysis of 27 observational studies consisting of 1720 patients undergoing tubal catheterization for proximal tubal obstruction, who attempted to conceive naturally after the procedure. Participants/materials, setting, methods: Systematic literature searches were performed in MEDLINE, EMBASE and the Cochrane Central Register of Controlled Trials. A total of 2195 titles and abstracts were reviewed. Only studies that reported outcomes when tubal catheterization was performed with no other tubal surgery were included. Twenty-seven cohort studies matched the inclusion criteria for the meta-analysis. Main results and the role of chance: The meta-analysis showed a pooled clinical pregnancy rate of 27% (95% CI 25-30%) after the use of tubal catheterization for unilateral or bilateral proximal tubal obstruction (27 studies, 1556 patients). In women with bilateral obstruction (14 studies, 617 patients), the clinical pregnancy rate was 27% (95% CI 23-32%). Our meta-analysis demonstrated that the pooled cumulative clinical pregnancy rates were 22.3% (95% CI 17.8-27.8%) at 6 months, 25.8% (95% CI 21.1-31.5%) at 9 months, 26.4% (95% CI 23.0-30.2%) at 12 months, 26.0% (95% CI 22.8-29.7%) at 18 months, 27.0% (95% CI 24.0-30.5%) at 24 months, 27.9% (95% CI 24.9-31.3%) at 36 months and 28.5% (95% CI 25.5-31.8%) at 48 months. The pooled live birth rate (14 studies, 551 patients) was 22% (95% CI 18-26%). The pooled ectopic pregnancy rate (27 studies, 1556 patients) was 4% (95% CI 3-5%). The included studies scored satisfactorily on the Newcastle-Ottawa quality assessment scale. Limitations, reasons for caution: The pooled clinical pregnancy rate after tubal catheterization was found to be almost comparable to that after IVF. However, included studies were small, non-comparative series with significant clinical heterogeneity in population characteristics, follow-up and surgical equipment, technique and experience. Wider implications of the findings: These findings suggest fallopian tube catheterization as an alternative strategy to IVF in patients presenting with proximal tubal obstruction. Further research should focus on comparing different surgical techniques of fallopian tube catheterization with IVF and provide cumulative reproductive outcomes over long-term follow-up. Study funding/competing interest(s): No funding was required and the authors have no competing interests to declare. Registration number: N/A.

Latrodectus geometricus (Aranea: Theridiidae) envenoming: Rapid resolution of symptoms following F(ab')2 antivenom therapy.

The Brown Widow spider (Latrodectus geometricus) is an invasive species whose geographic range has been expanding worldwide. It is a relative species of the Black Widow and Red-backed spiders of the genus Latrodectus. Despite its broad geographic distribution cases of Brown Widow envenomation have rarely been documented. The venom of L. geometricus is similar to the venom of L. mactans with the primary venom component being alpha-latrotoxin, and consequent envenoming by L. geometricus to humans has resulted in symptoms similar to those reported for other Latrodectus spp. Specific FDA approved Latrodectus antivenom (IgG) available in North America has been effectively used in treating venom-induced symptoms following L. mactans envenoming. The patient reported here involved a confirmed L. geometricus envenoming who was efficaciously treated with an alternately available F(ab')2 antivenom from Mexico.

Effects of chlorpyrifos on reproductive performances of guppy (Poecilia reticulata).

Guppy (Poecilia reticulata) was selected to investigate the effects of chlorpyrifos on reproductive performances. Male and female guppy with proven fertility were selected from our own colony and the groups of fish (n=72/group) were exposed to pre-determined chlorpyrifos concentrations (0.002 microg/l, 2 microg/l) based on the 96-h LC50 for guppy. Mating behavior of males was recorded on the 2nd day of exposure. Offspring were counted and survival recorded on the 14th day. Gonopodial thrusts (8/15 min) in 0.002 microg/l and (4/15 min) in 2 microg/l were significantly different from the control group (11/15 min). Similarly, live birth reduced significantly to 8/female in 2 microg/l compared to 27/female in the control group. Survival of offspring after 14 days was reduced to 47% in the 2 microg/l group compared to 94% of survival in the control. Our findings demonstrate that low soluble concentrations of chlorpyrifos affect mating behavior, number of offspring and offspring survival of guppy.

Estimation of lymphocyte percentage and number on the Coulter Counter, Model S Plus Phase II.

The Coulter Counter Model S Plus Phase II provided precise measurements of lymphocyte percentage and count and carry-over was negligible. Lymphocyte percentage values agreed well with those from the stained blood film except when the percentage was high and in these circumstances the instrument gave underestimates. When making artificial mixtures with increasing lymphocyte count a progressive underestimation of the lymphocyte percentage was also noted. The display of leucocyte volume distribution was found to be a useful attribute particularly when the instrument alerted the operator to "rejected" profiles. Rejection by the instrument proved to be a helpful function occurring in the myeloid leukaemias, erythroblastosis, and in some cases when the lymphocytes differed from normal--for example, glandular fever and chronic lymphocytic leukaemia.

Low concentrations of lorsban in water result in far reaching behavioral and histological effects in early life stages in guppy.

Chlorpyrifos (O,O-diethyl-O (3,5,6-trichlor-2-pyridyl) phosphorothioate) is a broad-spectrum organophosphate compound. A number of previous work of different countries, institutes, and individuals have confirmed that chlorpyrifos is very highly toxic to freshwater fish and to aquatic invertebrates. The acute toxicity and subacute toxic effects on different concentrations of chlorpyrifos in guppy were investigated in the current study. Twelve guppy juveniles (x 6) were exposed to a range of chlorpyrifos concentrations and 96 h. There was one control group. Subacute exposures were predetermined based on 96-h LC50 values. Fish were exposed to three concentrations 0.5, 1, and 2.0 microg/L chlorpyrifos (Lorsban) for 14 consecutive days. Numbers of live and dead juveniles, signs of paralysis, and deformations were monitored every 24 h. The acute toxicity results revealed that even low concentrations of Lorsban were toxic to guppy juveniles, and with toxicity being evident from 7.17 microg/L LC50 for 96 h at 26 +/- 1 degree C. Low concentrations of Lorsban were also responsible for changes in swimming behavior. Malformations were common to all treated groups but increased in the highest exposure group. Gill histology revealed several pathological changes, including loss and shortening of secondary lamellae. Collectively, the present study reveals that low concentrations of chlorpyrifos can be highly detrimental to guppy in the early life stages, with clear evidence of behavioral, morphologic, and histologic effects. The present findings warrant further studies.

Current practice in neonatal exchange transfusions: a retrospective audit based at one transfusion centre.

As a result of the widespread use of phototherapy, the need for neonatal exchange transfusion has declined markedly over the last 25 years. However, in spite of this, we have discovered a marked disparity in the number of requests for units of blood suitable for exchange transfusion made by neonatal units of similar size. A retrospective audit was therefore performed to establish current practice. A questionnaire was sent to consultant neonatologists and an audit trail of all units of blood issued from our Transfusion Centre for exchange transfusion over an 18-month period was followed. A significant finding was the large amount of overordering of blood by neonatologists, resulting in units produced expensively to high specification being given to other patients. Only 42% of the blood issued for exchange transfusions was actually used for that purpose. Also, published guidelines are not being adhered to, particularly with respect to the specification of the blood products being used. Better communication between neonatologists, hospital haematologists and transfusion medicine specialists would help to ensure that infants requiring exchange transfusion are given the best product and that valuable resources are not wasted.

Anti-allergic properties of the natural PAF antagonist yangambin.

In this study we examined the ability of the furofuran lignan yangambin to influence the local and systemic responses induced by antigen or PAF in actively sensitized or normal rats. Given intraperitoneally 1 h before stimulation, yangambin inhibited the pleural neutrophil and eosinophil infiltration evoked by the i.pl. injection of PAF or antigen into normal or 14 daysensitized rats whereas plasma exudation evoked by both stimuli was unaffected. The pleural neutrophil influx (6 h) after LTB4 stimulation was also significantly inhibited by yangambin. We also evidenced that the hemoconcentration, thrombocytopenia, and leucocytosis noted after i.v. PAF were all attenuated by yangambin. In actively sensitized rats, pretreatment with yangambin failed to modify the antigen-induced hemoconcentration and leucocytosis, but dose-dependently abrogated the thrombocytopenia noted 1 h post-stimulation. In vitro, the anaphylactic contraction of longitudinal jejunal segments to antigen challenge was significantly inhibited by yangambin (10(-5)-10(-4) M). Likewise, the contraction of jejunal segments from normal rats to PAF was markedly blocked by yangambin under conditions where the response to 5-hydroxytryptamine (5-HT) was not altered. In conclusion, our results show that antigen- and PAF-induced pleural neutrophil and eosinophil accumulation, but not exudation, is sensitive to treatment with yangambin. In addition, yangambin also suppressed the pleural neutrophil infiltration triggered by LTB4 as well as the blood thrombocytopenia and intestinal anaphylaxis elicited by antigen in rats. Thus, our findings indicate that yangambin shows an antagonistic action on receptors other than those of PAF, i.e., LTB4, and strongly suggest that it may be a useful drug in the treatment of some allergic inflammatory responses.