Impact of Human Colonization on the Landscape: A View from the Western Pacific.

v. ill. 23 cm.QuarterlyIn this paper we review and assess the impact of colonizing peoples on their landscape by focusing on two very different colonizing processes within the western Pacific. The first is the initial human colonization of New Guinea 45,000–40,000 years ago by hunter-foraging populations; the second is the colonization of smaller offshore islands of the Bismarck Archipelago, some 3,300 years ago, by peoples argued to have practiced agriculture: two different colonizing processes by two different groups of peoples with two different social structures practicing two very different subsistence strategies. The impact of these two colonization processes on the environment is compared and contrasted, and commonalities identified for the archaeological and vegetation record

Adefovir dipivoxil therapy for lamivudine-resistant hepatitis B in pre- and post-liver transplantation patients

Three-hundred and twenty-four patients were enrolled in an open-label, multicenter, international study in which pre- and post-liver transplantation (LT) patients with recurrent chronic hepatitis B (CHB) and evidence of lamivudine-resistant HBV were treated with adefovir dipivoxil 10 mg once daily. In the pre- and post-LT cohorts, 128 and 196 patients were treated for a median duration of 18.7 and 56.1 weeks, respectively. In patients who received 48 weeks of treatment, 81% of the pre-LT and 34% of the post-LT cohort achieved undetectable serum hepatitis B virus (HBV) DNA (Roche Amplicor Monitor(TM) polymerase chain reaction [PCR] assay lower limit of quantification [LLQ] < 400 copies/mL) with a median change in serum HBV DNA from baseline of -4.1 log(10) and -4.3 log(10) copies/mL, respectively. Serum alanine aminotransferase (ALT), albumin, bilirubin, and prothrombin time normalized in 76%, 81%, 50%, and 83% of pre-LT patients and 49%, 76%, 75%, and 20% of post-LT patients. The Child-Pugh-Turcotte (CPT) score improved in over 90% of patients in both cohorts. Genotypic analysis of 122 HBV baseline samples revealed that 98% of these patients had lamivudine-resistant mutant HBV. No adefovir resistance mutations were identified in patients after 48 weeks of therapy. One-year survival was 84% for pre-LT and 93% for post-LT patients (Kaplan-Meier analysis). Treatment-related adverse effects associated with adefovir dipivoxil in this setting were primarily mild to moderate in severity. In conclusion, 48 weeks of adefovir dipivoxil resulted in significant improvements in virologic, biochemical, and clinical parameters in CHB patients pre- and post-LT with lamivudine-resistant HBV

Risk of COVID-19 after natural infection or vaccinationResearch in context

Summary: Background: While vaccines have established utility against COVID-19, phase 3 efficacy studies have generally not comprehensively evaluated protection provided by previous infection or hybrid immunity (previous infection plus vaccination). Individual patient data from US government-supported harmonized vaccine trials provide an unprecedented sample population to address this issue. We characterized the protective efficacy of previous SARS-CoV-2 infection and hybrid immunity against COVID-19 early in the pandemic over three-to six-month follow-up and compared with vaccine-associated protection. Methods: In this post-hoc cross-protocol analysis of the Moderna, AstraZeneca, Janssen, and Novavax COVID-19 vaccine clinical trials, we allocated participants into four groups based on previous-infection status at enrolment and treatment: no previous infection/placebo; previous infection/placebo; no previous infection/vaccine; and previous infection/vaccine. The main outcome was RT-PCR-confirmed COVID-19 >7–15 days (per original protocols) after final study injection. We calculated crude and adjusted efficacy measures. Findings: Previous infection/placebo participants had a 92% decreased risk of future COVID-19 compared to no previous infection/placebo participants (overall hazard ratio [HR] ratio: 0.08; 95% CI: 0.05–0.13). Among single-dose Janssen participants, hybrid immunity conferred greater protection than vaccine alone (HR: 0.03; 95% CI: 0.01–0.10). Too few infections were observed to draw statistical inferences comparing hybrid immunity to vaccine alone for other trials. Vaccination, previous infection, and hybrid immunity all provided near-complete protection against severe disease. Interpretation: Previous infection, any hybrid immunity, and two-dose vaccination all provided substantial protection against symptomatic and severe COVID-19 through the early Delta period. Thus, as a surrogate for natural infection, vaccination remains the safest approach to protection. Funding: National Institutes of Health