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The 'red zone' usually refers to the first few weeks of the first semester at college, when female students are believed to be at greatest risk for experiencing unwanted sex. We tested this notion using data from a survey study of 207 first-and second-year students (121 women, 84 men) at a small, liberal arts university. Results demonstrated only one significant elevation in incidence rates of first- and second-year women's unwanted sexual experiences (sexual touching, attempted and completed anal, oral, and vaginal sex), between the end of the first month and fall break (mid-October) during the second year at school. Previous research and local information about the relevant behaviors of sorority and fraternity members is discussed in light of these findings to provide heuristic material for further empirical testing. Because risk may involve both temporal and situational factors, systematic collection and dissemination of local data are recommended. [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria in humans is caused by any of four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae). These parasites are transmitted by the bite of an infective female Anopheles sp. mosquito. The majority of malaria infections in the United States occur among persons who have traveled to or from areas with ongoing malaria transmission. In the United States, cases can occur through exposure to infected blood products, congenital transmission, or local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers.Period Covered: This report summarizes cases in persons with onset of illness in 2005 and summarizes trends during previous years.Description of System: Malaria cases confirmed by blood film or polymerase chain reaction (PCR) are mandated to be reported to local and state health departments by health-care providers or laboratory staff. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report.Results: CDC received reports of 1,528 cases of malaria, including seven fatal cases, with an onset of symptoms in 2005 among persons in the United States or one of its territories. This number represents an increase of 15.4% from the 1,324 cases reported for 2004. P. falciparum, P. vivax, P. malariae, and P. ovale were identified in 48.6%, 22.1%, 3.5%, and 2.5% of cases, respectively. Twelve patients (0.8% of total) were infected by two or more species. The infecting species was unreported or undetermined in 22.6% of cases. Compared with 2004, the largest increases in cases came from the Americas (23.1%; n = 213) and Asia and the Middle East (18.6%; n = 204). On the basis of estimated volume of travel, the highest estimated case rates of malaria among travelers occurred among those returning from West Africa. Of 870 U.S. civilians who acquired malaria abroad, only 160 (18.4%) reported that they had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Two patients became infected in the United States, both attributed to congenital transmission; both were infected with P. vivax. Seven deaths were attributed to malaria, all caused by infection with P. falciparum.Interpretation: The 15.4% increase in malaria cases in 2005, compared with 2004, resulted primarily from increases in the number of cases reported from Asia and the Middle East and from the Americas. This increase might in part reflect more complete reporting and in part increased travel to malarious areas. No change was noted in proportions of cases from other areas of the world, or in species responsible for the infection. In the majority of reported cases, U.S. civilians who acquired infection abroad had not adhered to a chemoprophylaxis regimen that was appropriate for the country in which they acquired malaria. U.S. civilians who traveled to West Africa had the highest estimated relative case rate.Public Health Actions: Additional investigations were conducted for the seven fatal cases and two infections acquired in the United States. Persons traveling to a malarious area should take one of the recommended chemoprophylaxis regimens appropriate for the region of travel and use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently has a fever or influenza-like symptoms should seek medical care immediately and report their travel history to the clinician; investigation should include at least one blood-film test for malaria. Malaria infections can be fatal if not diagnosed and treated promptly. Recommendations concerning malaria prevention can be obtained from CDC at http://www.cdc.gov/travel or by calling the Malaria Hotline (telephone 770-488-7788). Recommendations for malaria treatment can be obtained at http://www.cdc.gov/malaria/diagnosis_treatment/treatment.htm or by calling the Malaria Hotline. [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria in humans is caused by any of four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae). These parasites are transmitted by the bite of an infective female Anopheles sp. mosquito. The majority of malaria infections in the United States occur among persons who have traveled to areas with ongoing malaria transmission. In the United States, cases can occur through exposure to infected blood products, congenital transmission, or local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers.Period Covered: This report summarizes cases in persons with onset of illness in 2004 and summarizes trends during previous years.Description of System: Malaria cases confirmed by blood film are mandated to be reported to local and state health departments by health-care providers or laboratory staff. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report.Results: CDC received reports of 1,324 cases of malaria, including four fatal cases, with an onset of symptoms in 2004 among persons in the United States or one of its territories. This number represents an increase of 3.6% from the 1,278 cases reported for 2003. P. falciparum, P. vivax, P. malariae, and P. ovale were identified in 49.6%, 23.8%, 3.6%, and 2.0% of cases, respectively. Seventeen patients (1.3% of total) were infected by two or more species. The infecting species was unreported or undetermined in 262 (19.8%) cases. Compared with 2003, the number of reported malaria cases acquired in the Americas (n = 173) increased 17.7%, whereas the number of cases acquired in Asia (n = 172) and Africa (n = 809) decreased 2.8% and 3.7%, respectively. Of 775 U.S. civilians who acquired malaria abroad, only 160 (20.6%) reported that they had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Four patients became infected in the United States; three cases were attributed to congenital transmission and one to laboratory-related mosquitoborne transmission. Four deaths were attributed to malaria, including two caused by P. falciparum, one by P. vivax, and one by a mixed infection with P. falciparum and P. malariae.Interpretation: The 3.6% increase in malaria cases in 2004, compared with 2003, resulted primarily from an increase in the number of cases acquired in the Americas but was offset by a decrease in the number of cases acquired in Africa and Asia. This limited increase might reflect local changes in disease transmission, increased travel to regions in which malaria is endemic, or fluctuations in reporting to state and local health departments. These changes likely reflect expected variation in annual reporting and should not be interpreted as indicating a longer-term trend. In the majority of reported cases, U.S. civilians who acquired infection abroad had not adhered to a chemoprophylaxis regimen that was appropriate for the country in which they acquired malaria.Public Health Actions: Additional investigations were conducted for the four fatal cases and four infections acquired in the United States. Persons traveling to a malarious area should take one of the recommended chemoprophylaxis regimens appropriate for the region of travel and use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently has a fever or influenza-like symptoms should seek medical care immediately and report their travel history to the clinician; investigation should include a blood-film test for malaria. Malaria infections can be fatal if not diagnosed and treated promptly. Recommendations concerning malaria prevention can be obtained from CDC at http://www.cdc.gov/travel or by calling the Malaria Hotline at telephone 770-488-7788. Recommendations concerning malaria treatment can be obtained at http://www.cdc.gov/malaria/diagnosis_treatment/treatment or by calling the Malaria Hotline. [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria in humans is caused by any of four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae). These parasites are transmitted by the bite of an infective female Anopheles sp. mosquito. The majority of malaria infections in the United States occur among persons who have traveled to areas with ongoing transmission. In the United States, cases can also occur through exposure to infected blood products, by congenital transmission, or by local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers.Period Covered: This report covers cases with onset of illness in 2003, and summarizes trends over previous years.Description of System: Malaria cases confirmed by blood film are mandated to be reported to local and state health departments by health-care providers or laboratory staff. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report.Results: CDC received reports of 1,278 cases of malaria with an onset of symptoms in 2003, including seven fatal cases, among persons in the United States or one of its territories. This number represents a decrease of 4.4% from the 1,337 cases reported for 2002. P. falciparum, P. vivax, P. malariae, and P. ovale were identified in 53.3%, 22.9%, 3.6%, and 2.6% of cases, respectively. Twelve patients (0.9% of total) were infected by two or more species. The infecting species was unreported or undetermined in 212 (16.6%) cases. Compared with 2002, the number of reported malaria cases acquired in Asia (n = 177) and the Americas (n = 147) increased by 3.5% and 4.3% respectively, whereas the number of cases acquired in Africa (n = 840) decreased by 7.0%. Of 762 U.S. civilians who acquired malaria abroad, 132 (17.3%) reported that they had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Ten patients became infected in the United States, including one probable transfusion-related, one in which epidemiologic investigations failed to identify any apparent mode of acquisition, and eight which were introduced cases as a result of local mosquitoborne transmission. Of the seven deaths attributed to malaria, five were caused by P. falciparum, and a species was not identified in the other two.Interpretation: The 4.4% decrease in malaria cases in 2003, compared with 2002, resulted primarily from a decrease in cases acquired in Africa, but this decrease was offset by an increase in the number of cases acquired in the Americas and Asia. This small decrease probably represents year-to-year variation in malaria cases, but also could have resulted from local changes in disease transmission, decreased travel to malaria-endemic regions, or fluctuation in reporting to state and local health departments. In the majority of reported cases, U.S. civilians who acquired infection abroad were not on an appropriate chemoprophylaxis regimen for the country in which they acquired malaria.Public Health Actions: Additional information was obtained concerning the seven fatal cases and the 10 infections acquired in the United States. Persons traveling to a malarious area should take one of the recommended chemoprophylaxis regimens appropriate for the region of travel, and travelers should use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently experiences a fever or influenza-like symptoms should seek medical care immediately and report their travel history to the clinician; investigation should include a blood-film test for malaria. Malaria infections can be fatal if not diagnosed and treated promptly. Recommendations concerning malaria prevention can be obtained from CDC by calling the Malaria Hotline at 770-488-7788 or by accessing CDC's Internet site at http://www.cdc.gov/travel. Recommendations concerning diagnosis of malaria and its treatment can be obtained by calling the Malaria Hotline or accessing CDC's Internet site at http://www.cdc.gov/malaria/diagnosis_treatment/treatment.htm [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria is caused by any of four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae). These parasites are transmitted by the bite of an infective female Anopheles species mosquito. The majority of malaria infections in the United States occur among persons who have traveled to areas with ongoing transmission. In the United States, cases can occur through exposure to infected blood products, by congenital transmission, or by local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers. Period Covered: This report covers cases with onset of illness in 2002. Description of System: Malaria cases confirmed by blood film are reported to local and state health departments by health-care providers or laboratory staff. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report. Results: CDC received reports of 1,337 cases of malaria with an onset of symptoms in 2002 among persons in the United States or one of its territories. This number represents a decrease of 3.3% from the 1,383 cases reported for 2001. P. falciparum, P. vivax, P. malariae, and P. ovale were identified in 52.3%, 25.4%, 2.8%, and 2.8% of cases, respectively. Eleven patients (0.8% of total) were infected by >2 species. The infecting species was unreported or undetermined in 213 (15.9%) cases. Compared with 2001, the number of reported malaria cases acquired in Asia (n = 171) and Africa (n = 903) increased by 4.3% and 1.9%, respectively, whereas the number of cases acquired in the Americas (n = 141) decreased by 41.2%. Of 849 U.S. civilians who acquired malaria abroad, 317 (37.3%) reported that they had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Five patients became infected in the United States, one through congenital transmission, one probable transfusion-related, and three whose infection cannot be linked epidemiologically to secondary cases. Eight deaths were attributed to malaria. All deaths were caused by P. falciparum. Interpretation: The 3.3% decrease in malaria cases in 2002, compared with 2001, resulted primarily from a marked decrease in cases acquired in the Americas, but this decrease was offset somewhat by an increase in the number of cases acquired in Africa and Asia. This limited decrease probably represents year-to-year variation in malaria cases, but also could have resulted from local changes in disease transmission, decreased travel to malaria-endemic regions, fluctuation in reporting to state and local health departments, or an increased use of effective antimalarial chemoprophylaxis. In the majority of reported cases, U.S. civilians who acquired infection abroad were not on an appropriate chemoprophylaxis regimen for the country in which they acquired malaria. Public Health Actions: Additional information was obtained concerning the eight fatal cases and the five infections acquired in the United States. Persons traveling to a malarious area should take one of the recommended chemoprophylaxis regimens appropriate for the region of travel, and travelers should use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently experiences a fever or influenza-like symptoms should seek medical care immediately and report their travel history to the clinician; investigation should include a blood-film test for malaria. Malaria infections can be fatal if not diagnosed and treated promptly. Recommendations concerning malaria prevention can be obtained from CDC by calling the Malaria Hotline at 770-488-7788 or by accessing CDC's Internet site at http://www.cdc.gov/travel. [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria is caused by any of four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae). These parasites are transmitted by the bite of an infective female Anopheles sp. mosquito. The majority of malaria infections in the United States occur among persons who have traveled to areas with ongoing transmission. In the United States, cases can occur through exposure to infected blood products, by congenital transmission, or by local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers.Period Covered: This report covers cases with onset of illness in 2001.Description of System: Malaria cases confirmed by blood film are reported to local and state health departments by health-care providers or laboratory staff. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report.Results: CDC received reports of 1,383 cases of malaria with an onset of symptoms in 2001 among persons in the United States or one of its territories. This number represents a decrease of 1.4% from the 1,402 cases reported for 2000. P. falciparum, P. vivax, P. malariae, and P. ovale were identified in 50.1%, 27.8%, 4.5%, and 3.6% of cases, respectively. Fourteen patients (1.0% of total) were infected by >/=2 species. The infecting species was unreported or undetermined in 179 (12.9%) cases. Compared with 2000, the number of reported malaria cases acquired in Africa increased by 13.2% (n = 886), whereas the number of cases acquired in Asia (n = 163) and the Americas (n = 240) decreased by 31.5% and 11.4%, respectively. Of 891 U.S. civilians who acquired malaria abroad, 180 (20.2%) reported that they had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Two patients became infected in the United States, one through congenital transmission and one whose infection cannot be linked epidemiologically to secondary cases. Eleven deaths were attributed to malaria, 10 caused by P. falciparum and one caused by P. ovale.Interpretation: The 1.4% decrease in malaria cases in 2001, compared with 2000, resulted primarily from a decrease in cases acquired in Asia and the Americas, but this decrease was offset by an increase in the number of cases acquired in Africa. This decrease probably represents year-to-year variation in malaria cases, but also could have resulted from local changes in disease transmission, decreased travel to malaria-endemic regions, fluctuation in reporting to state and local health departments, or an increased use of effective antimalarial chemoprophylaxis. In the majority of reported cases, U.S. civilians who acquired infection abroad were not on an appropriate chemoprophylaxis regimen for the country in which they acquired malaria.Public Health Actions: Additional information was obtained concerning the 11 fatal cases and the two infections acquired in the United States. Persons traveling to a malarious area should take one of the recommended chemoprophylaxis regimens appropriate for the region of travel, and travelers should use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently develops a fever or influenza-like symptoms should seek medical care immediately and report their travel history to the clinician; investigation should include a blood-film test for malaria. Malaria infections can be fatal if not diagnosed and treated promptly. Recommendations concerning malaria prevention can be obtained from CDC by calling the Malaria Hotline at 770-488-7788 or by accessing CDC's Internet site at http://www.cdc.gov/travel. [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria is caused by four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae). Malaria is transmitted by the bite of an infective female Anopheles sp. mosquito. The majority of malaria infections in the United States occur among persons who have traveled to areas with ongoing transmission. In the United States, cases can occur through exposure to infected blood products, by congenital transmission, or locally through mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers.Period Covered: Cases with onset of illness during 2000.Description of System: Malaria cases confirmed by blood smear are reported to local and state health departments by health-care providers or laboratory staff. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report.Results: CDC received reports of 1,402 cases of malaria with an onset of symptoms during 2000 among persons in the United States or one of its territories. This number represents a decrease of 9.0% from the 1,540 cases reported for 1999. P. falciparum, P. vivax, P. malariae, and P. ovale were identified in 43.6%, 37.2%, 4.8%, and 2.3% of cases, respectively. Nine patients (0.6% of total) were infected by >/=2 species. The infecting species was unreported or undetermined in 161 (11.5%) cases. Compared with 1999, the number of reported malaria cases acquired in Africa decreased by 13.1% (n = 783), and a decrease of 3.3% (n = 238) occurred in cases acquired in Asia. Cases from the Americas decreased by 1.1% (n = 271) from 1999. Of 825 U.S. civilians who acquired malaria abroad, 190 (23.0%) reported that they had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Four patients became infected in the United States, two through congenital transmission and two through probable induced transmission. Six deaths were attributed to malaria, four caused by P. falciparum, one caused by P. malariae, and one by P. ovale.Interpretation: The 9.0% decrease in malaria cases in 2000, compared with 1999, resulted primarily from decreases in cases acquired in Africa and Asia. This decrease could have resulted from local changes in disease transmission, decreased travel to these regions, fluctuation in reporting to state and local health departments, or an increased use of effective antimalarial chemoprophylaxis. In the majority of reported cases, U.S. civilians who acquired infection abroad were not on an appropriate chemoprophylaxis regimen for the country in which they acquired malaria.Public Health Actions: Additional information was obtained concerning the six fatal cases and the four infections acquired in the United States. Persons traveling to a malarious area should take one of the recommended chemoprophylaxis regimens appropriate for the region of travel, and travelers should use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently develops a fever or influenza-like symptoms should seek medical care immediately and report their travel history to the clinician; investigation should include a blood-film test for malaria. Malaria infections can be fatal if not diagnosed and treated promptly. Recommendations concerning malaria prevention can be obtained from CDC by calling the Malaria Hotline at 770-488-7788 or by accessing CDC's Internet site at http://www.cdc.gov/travel. [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria is caused by four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae). Malaria is transmitted by the bite of an infective female Anopheles sp. mosquito. The majority of malaria infections in the United States occur in persons who have traveled to areas with ongoing transmission. In the United States, cases can occur through exposure to infected blood products, by congenital transmission, or locally through mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers.Period Covered: Cases with onset of illness during 1999.Description of System: Malaria cases confirmed by blood films are reported to local and state health departments by health-care providers or laboratory staff. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report.esults: CDC received reports of 1,540 cases of malaria with an onset of symptoms during 1999 among persons in the United States or one of its territories. This number represents an increase of 25.5% from the 1,227 cases reported for 1998. P. falciparum, P. vivax, P. malariae, and P. ovale were identified in 46.0%, 30.7%, 4.6%, and 3.6% of cases, respectively. More than one species was present in 12 patients (0.8% of total). The infecting species was unreported or undetermined in 223 (14.5%) cases. The number of reported malaria cases acquired in Africa increased 27.6% (n = 901), compared with 1998, and an increase of 2.9% (n = 246) occurred in cases acquired in Asia, compared with 1998. Cases from the Americas increased by 19.7% (n = 274) from 1998. Of 831 U.S. civilians who acquired malaria abroad, 159 (19.1%) reported that they had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Three patients became infected in the United States, all through probable local mosquitoborne transmission. Five deaths were attributed to malaria, all caused by P. falciparum.Interpretation: The 25.5% increase in malaria cases in 1999, compared with 1998, resulted primarily from increases in cases acquired in Africa and the Americas. This increase is possibly related to a change in the system by which states report to CDC, but it could also have resulted from local changes in disease transmission, increased travel to these regions, improved reporting to state and local health departments, or a decreased use of effective antimalarial chemoprophylaxis. In the majority of reported cases, U.S. civilians who acquired infection abroad were not on an appropriate chemoprophylaxis regimen for the country where they acquired malaria.Public Health Actions: Additional information was obtained concerning the five fatal cases and the three infections acquired in the United States. The NMSS surveillance form was modified to gather more detailed information regarding compliance with prescribed chemoprophylaxis regimens. Persons traveling to a malarious area should take one of the recommended chemoprophylaxis regimens appropriate to the region of travel, and travelers should use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently develops a fever or influenza-like symptoms should seek medical care immediately; investigation should include a blood-film test for malaria. Malaria infections can be fatal if not diagnosed and treated promptly. Recommendations concerning prevention of malaria can be obtained from CDC. [ABSTRACT FROM AUTHOR]

Problem/Condition: Human malaria is caused by one or more of four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae). The protozoa are transmitted by the bite of an infective female Anopheles species mosquito. The majority of malaria infections in the United States occur among persons who have traveled to areas with endemic transmission. Cases occasionally occur that are acquired through exposure to infected blood products, by congenital transmission, or by local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers.Reporting Period: Cases with an onset of symptoms during 1998.Description of System: Malaria cases confirmed by blood smear are reported to local and state health departments by health-care providers and laboratory staff members. Case investigations are conducted by local and state health departments, and reports are sent to CDC through the National Malaria Surveillance System (NMSS). This report uses NMSS data.Results: CDC received reports of 1,227 cases of malaria with onsets of symptoms in 1998, among persons in the United States and its territories. This number represents a decrease of 20.5% from the 1,544 cases reported during 1997. P. falciparum, P. vivax, P. malariae, and P. ovale were identified in 42.8%, 37.8%, 3.5%, and 2.1% of cases, respectively. More than one species was present in seven patients (0.6% of total). The infecting species was not determined in 162 (13.2%) cases. Compared with reported cases in 1997, reported malaria cases acquired in Africa increased by 1.3% (n = 706); those acquired in Asia decreased by 52.1% (n = 239); and those acquired in the Americas decreased by 6.5% (n = 229). Of 636 U.S. civilians who acquired malaria abroad, 126 (19.8%) reportedly had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Five persons became infected in the United States. One case was congenitally acquired; one was acquired by blood transfusion; and three were isolated cases that could not be epidemiologically linked to another case. Four deaths were attributed to malaria.Interpretation: The 20.5% decrease in malaria cases during 1998 compared with 1997 resulted primarily from decreases in P. vivax cases acquired in Asia among non-U.S. civilians. This decrease could have resulted from local changes in disease transmission, decreased immigration from the region, decreased travel to the region, incomplete reporting from state and local health departments, or increased use of effective antimalarial chemoprophylaxis. In a majority of reported cases, U.S. civilians who acquired infection abroad had not taken an appropriate chemoprophylaxis regimen for the country where they acquired malaria.Public Health Actions Taken: Additional information was obtained from state and local health departments and clinics concerning the four fatal cases and the five infections acquired in the United States. Persons traveling to a malarious area should take a recommended chemoprophylaxis regimen and use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and subsequently develops fever or influenza-like symptoms should seek medical care immediately; the investigation should include a blood smear for malaria. Malaria infections can be fatal if not diagnosed and treated promptly. Current recommendations concerning prevention and treatment of malaria can be obtained from CDC. [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria is caused by four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae), which are transmitted by the bite of an infective female Anopheles sp. mosquito. Most malaria infections in the United States occur in persons who have traveled to areas with ongoing transmission. Occasionally, cases occur in the United States through exposure to infected blood products, by congenital transmission, or by local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers. Reporting Period Covered: Cases with onset of illness during 1997. Description of System: Malaria cases confirmed by blood smears are reported to local and/or state health departments by health-care providers and/or laboratory staff. Case investigations are conducted by local and/or state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report. Results: CDC received reports of 1,544 cases of malaria with onset of symptoms during 1997 among persons in the United States or one of its territories. This number represents an increase of 10.9% from the 1,392 cases reported for 1996. P. vivax, P. falciparum, P. malariae, and P. ovale were identified in 48.9%, 36.7%, 3.1%, and 2.0% of cases, respectively. More than one species was present in nine patients (0.6% of total). The infecting species was not determined in 134 (8.7%) cases.The number of reported malaria cases acquired in Africa increased by 38.0% (n=697) compared with 1996, and cases acquired in Asia increased by 12.9% (n=499) compared with 1996. Cases acquired in the Americas decreased by 9.3% (n=245) compared with 1996. Of 695 U.S. civilians who acquired malaria abroad, 144 (20.7%) reported that they had followed a chemoprophylactic drug regimen recommended by CDC for the area where they had traveled.Five patients became infected in the United States. Three of these cases were con-genitally acquired; one was acquired by a blood transfusion; and one was acquired by a needle stick. Six deaths were attributed to malaria. Interpretation: The 10.9% increase in malaria cases in 1997 compared with 1996 resulted from increases in cases acquired in Africa and Asia. This increase could have resulted from local changes in disease transmission, increased travel to these regions, improved reporting from state and local health departments, or a decreased use of effective antimalarial chemoprophylaxis. In most reported cases, U.S. civilians who acquired infection abroad were not on an appropriate chemoprophylaxis regimen for the country where they acquired malaria. Public Health Actions: Additional information was obtained concerning the six fatal cases and the five infections acquired in the United States. [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria is caused by four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae), which are transmitted by the bite of an infected female Anopheles sp. mosquito. Most malaria infections in the United States occur in persons who have traveled to areas with ongoing transmission. Occasionally, cases occur in the United States through exposure to infected blood products, by congenital transmission, or by local mosquitoborne transmission. National public health surveillance for malaria is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers. Reporting Period Covered: Cases with onset of illness during 1996. Description of System: Malaria cases confirmed by blood smears are reported to local and/or state health departments by health-care providers and/or laboratory staff. Case investigations are conducted by local and/or state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report. Results: CDC received reports of 1,392 cases of malaria with onset of symptoms during 1996 among persons in the United States or one of its territories. This number represents an increase of 19.3% from the 1,167 cases reported for 1995. P. vivax, P. falciparum, P. malariae, and P. ovale were identified in 47.4% 37.4%, 5.4%, and 2.0% of cases, respectively. More than one species was present in four patients (0.3% of total). The infecting species was not determined in 104 (7.5%) cases.The number of reported malaria cases acquired in Africa (n=585)increased by 12.7% compared with 1995; cases acquired in Asia increased by 31.9% (n=442); and cases acquired in the Americas increased by 13.0% (n=278). Of 614 U.S. civilians who acquired malaria abroad, 97 (15.8%) had followed a chemoprophylactic drug regimen recom-mended by CDC for the area where they had traveled. Eleven patients became infected in the United States. Of these 11 cases, three were congenitally acquired; one was acquired by organ transplantation; one was acquired by a blood transfusion; two were acquired through infusion using a heparin lock; and one was acquired by a mosquito bite in a laboratory setting. In three cases, the source of infection was unknown. Five deaths were attributed to malaria. Interpretation: The 19.3% increase in malaria cases in 1996 compared with 1995 resulted primarily from increases in cases acquired in Africa and Asia. This increase could have resulted from local changes in disease transmission, increased travel to these regions, improved reporting from state and local health departments, or a decreased use of effective antimalarial chemoprophylaxis. In most reported cases, U.S. civilians who acquired infection abroad were not on an appropriate chemoprophylaxis regimen for the country where they acquired malaria. Public Health Actions: Additional information was obtained concerning the five fatal cases and the 11 infections acquired in the United States. In 1996, malaria prevention guidelines were updated and distributed to health-care providers. [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria is caused by four species of Plasmodium (i.e., P. falci-parum, P. vivax, P. ovale, or P. malariae), which are transmitted by the bite of an infective female Anopheles sp. mosquito. Most malaria infections in the United States occur among persons who have traveled to areas with ongoing transmission. Occasionally, cases occur in the United States through exposure to infected blood products, by congenital transmission, or by local mosquito-borne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers. Reporting Period: Cases with onset of illness during 1995. Description of System: Malaria cases confirmed by blood smears are reported to local and/or state health departments by health-care providers and/or laboratory staff. Case investigations are conducted by local and/or state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report. Results: CDC received reports of 1,167 cases of malaria with onset of symptoms during 1995 among persons in the United States or one of its territories. This number represents an increase of 15% from the 1,014 cases reported for 1994. P. vivax, P. falci-parum, P. malariae, and P. ovale were identified in 48.2%, 38.6%, 3.9%, and 2.2% of cases, respectively. More than one species was present in three patients (0.3% of total). The infecting species was not determined in 80 (6.9%) cases. The number of reported malaria cases acquired in Africa (n=519) remained approximately the same as in 1994 (n=517); cases acquired in Asia increased by 32.4% (n=335); and cases acquired in the Americas increased by 37.4 % (n=246). Of 591 U.S. civilians who acquired malaria abroad, 15.6% had followed a chemoprophylactic drug regimen recommended by CDC for the area where they had traveled. Nine patients became infected in the United States. Of these nine cases, five were congenitally acquired; one was acquired by organ transplantation; and one was acquired by a blood transfusion. For two of the nine cases, the source of infection was unknown. Six deaths were attributed to malaria. Interpretation: The 15% increase in malaria cases in 1995 compared with 1994 resulted primarily from increases in cases acquired in Asia and the Americas, most notably a 100% increase in the number of cases reported from South America. This change could have resulted from local changes in disease transmission, travel patterns, reporting errors, or a decreased use of effective antimalarial chemoprophylaxis. In most reported cases, U.S. civilians who acquired infection abroad were not on an appropriate chemoprophylaxis regimen for the country where they acquired malaria. Actions Taken: Additional information was obtained concerning the six fatal cases and the nine infections acquired in the United States. Malaria prevention guidelines were updated and distributed to health-care providers. Persons traveling to a malarious area should take the recommended chemoprophylaxis regimen and use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently develops a fever or influenza-like symptoms should seek medical care; investigation should include a blood smear for malaria. Malaria infections can be fatal if not diagnosed and treated promptly. Recommendations concerning prevention and treatment of malaria can be obtained from CDC. [ABSTRACT FROM AUTHOR]

In this exploratory mixed-methods analysis of students' perceptions of inclusion in introductory STEM courses for STEM majors, we asked students to rate inclusion in their class and to provide an open-text explanation of their rating. Analyzing 1930 qualitative responses resulted in a codebook containing academic, identity, and nonspecific categories. The majority of responses (>80%) cited academic factors such as interactions between students and instructors or course elements and policies. Most academic responses aligned with evidence-based teaching practices fostering inclusion, describing a range of strategies and policies instructors can implement to increase students' perceptions of inclusion. A small number of student responses indicated that their perception of the required knowledge background for the course impacted course inclusivity. Few differences in frequency distributions were found between subgroups examined (gender, race and ethnicity, self-reported inclusion score, and discipline). Additionally, tracking a subset of students (135) across three courses revealed that most (80%) cited different factors influencing their perception of inclusion in each course. This suggests students' perceptions of inclusive practices are complex, and most students recognize multiple factors that influence their inclusion. Overall, our findings suggest instructors can significantly influence students' perceptions of inclusion by using multiple inclusive teaching strategies and course policies.

Students struggle to regulate their learning during independent study sessions. In this study, we ask whether an online behavioral intervention helped introductory students decrease distraction while studying. The intervention consisted of exam 1 reflection, exam 2 planning, and exam 2 reflection exercises. During planning, students formed a goal, mentally contrasted (MC) a positive outcome of their goal to their present reality, identified an obstacle, and formed an implementation intention (II) to overcome that obstacle. During reflection, students self-reported their distraction while studying. Distraction was the most frequently reported study obstacle , and decreasing distraction was the second most frequently reported study goal . While students who aimed to decrease distraction as a goal did not follow through, students who planned for distraction obstacles did follow through on decreasing distraction levels. Only about half of students generated an II that aligned with their study goal, which may provide one reason for the opposing follow-through of distraction framed as a goal versus as an obstacle. Lastly, we examined the specificity of students' II's and found no relationship with follow-through. Overall, MC with II holds promise as a self-regulatory technique to help introductory biology students change their behaviors while studying.

The horse reference genome assemblies, EquCab2.0 and EquCab3.0, have enabled great advancements in the equine genomics field, from tools to novel discoveries. However, significant gaps of knowledge regarding genome function remain, hindering the study of complex traits in horses. In an effort to address these gaps and with inspiration from the Encyclopedia of DNA Elements (ENCODE) project, the equine Functional Annotation of Animal Genome (FAANG) initiative was proposed to bridge the gap between genome and gene expression, providing further insights into functional regulation within the horse genome. Three years after launching the initiative, the equine FAANG group has generated data from more than 400 experiments using over 50 tissues, targeting a variety of regulatory features of the equine genome. In this review, we examine how valuable lessons learned from the ENCODE project informed our decisions in the equine FAANG project. We report the current state of the equine FAANG project and discuss how FAANG can serve as a template for future expansion of functional annotation in the equine genome and be used as a reference for studies of complex traits in horse. A well-annotated reference functional atlas will also help advance equine genetics in the pan-genome and precision medicine era.

Objective: Egg consumption is often discouraged due to cholesterol content; however, recent studies have not demonstrated a clear adverse influence of eggs on blood lipids. Furthermore, exercise training promotes improved lipids and blood pressure. The purpose of the study was to examine the effect of eating an isoenergetic (400 kcal) egg-based (including two eggs per day) versus bagel-based breakfasts, daily, combined with resistance training three times per week, prior to breakfast, on plasma lipids, glucose, insulin, insulin sensitivity and blood pressure in untrained individuals., Methods: Twenty-five healthy adult men and women (18-35 years of age) participated in the twelve week study following random assignment to study groups. Lipids and blood pressure were examined at baseline and after 6 and 12 weeks., Results: Plasma triglycerides (TG) decreased significantly in the egg- based breakfast (EBB) group from baseline to six weeks (p = 0.011) and from six to twelve weeks (p = 0.045). A significant (p = 0.033) decrease in insulin sensitivity was observed in the bagel-based breakfast (BBB) group from zero to six weeks. No significant effects on systolic blood pressure, diastolic blood pressure, total cholesterol, high density lipoprotein- cholesterol or low density lipoprotein cholesterol were detected., Conclusion: Overall, daily breakfasts including two eggs for twelve weeks did not adversely affect lipids during a resistance training program and promoted improvements in plasma TG.

Objective: This study aimed to identify predictors of acceptance of intensive treatment and of participation in a randomized controlled trial (RCT) among women with anorexia nervosa (AN)., Method: Participant data were drawn from a tertiary care intensive treatment programme including a previously published RCT. Women with AN (N = 106) were offered intensive treatment, and 69 were approached to participate in an RCT of olanzapine's efficacy as an adjunctive treatment for AN. AN subtype and pretreatment psychological variables were used to predict acceptance of intensive treatment and RCT participation., Results: AN binge purge subtype and higher depression and body dissatisfaction predicted intensive treatment acceptance. No variable predicted RCT participation among treatment acceptors., Discussion: Clinicians may focus on enhancing motivation or use a stepped care approach to increase intensive treatment acceptance especially among women with AN-restricting type and among all those with AN who have lower levels of distress., (Copyright © 2011 John Wiley & Sons, Ltd and Eating Disorders Association.)

Time-of-flight secondary ion mass spectrometry (TOF-SIMS) is an established technique for the characterization of solid sample surfaces. The introduction of polyatomic ion beams, such as C(60), has provided the associated ability to perform molecular depth-profiling and 3D molecular imaging. However, not all samples perform equally under C(60) bombardment, and it is probably naïve to think that there will be an ion beam that will be applicable in all situations. It is therefore important to explore the potential of other candidates. A systematic study of the suitability of argon gas cluster ion beams (Ar-GCIBs) of general composition Ar(n)(+), where n = 60-3000, as primary particles in TOF-SIMS analysis has been performed. We have assessed the potential of the Ar-GCIBs for molecular depth-profiling in terms of damage accumulation and sputter rate and also as analysis beams where spectral quality and secondary ion yields are considered. We present results with direct comparison with C(60) ions on the same sample in the same instrument on polymer, polymer additive, and biomolecular samples, including lipids and small peptides. Large argon clusters show reduced damage accumulation compared with C(60) with an approximately constant sputter rate as a function of Ar cluster size. Further, on some samples, large argon clusters produce changes in the mass spectra indicative of a more gentle ejection mechanism. However, there also appears to be a reduction in the ionization of secondary species as the size of the Ar cluster increases.

Objective: Anorexia nervosa is associated with high mortality, morbidity, and treatment costs. Olanzapine, an atypical antipsychotic, is known to result in weight gain in other patient populations. The objective of this trial was to assess the efficacy of olanzapine in promoting weight gain and in reducing obsessive symptoms among adult women with anorexia nervosa., Method: The study was a double-blind, placebo-controlled, 10-week flexible dose trial in which patients with anorexia nervosa (N=34) were randomly assigned to either olanzapine plus day hospital treatment or placebo plus day hospital treatment., Results: Compared with placebo, olanzapine resulted in a greater rate of increase in weight, earlier achievement of target body mass index, and a greater rate of decrease in obsessive symptoms. No differences in adverse effects were observed between the two treatment conditions., Conclusions: These preliminary results suggest that olanzapine may be safely used in achieving more rapid weight gain and improvement in obsessive symptoms among women with anorexia nervosa. Replication, in the form of a large multicenter trial, is recommended.

Many of the threats to the persistence of populations of sensitive species have physiological or pathological mechanisms, and those mechanisms are best understood through the inherently integrative discipline of physiological ecology. The desert tortoise was listed under the Endangered Species Act largely due to a newly recognized upper respiratory disease thought to cause mortality in individuals and severe declines in populations. Numerous hypotheses about the threats to the persistence of desert tortoise populations involve acquisition of nutrients, and its connection to stress and disease. The nutritional wisdom hypothesis posits that animals should forage not for particular food items, but instead, for particular nutrients such as calcium and phosphorus used in building bones. The optimal foraging hypothesis suggests that, in circumstances of resource abundance, tortoises should forage as dietary specialists as a means of maximizing intake of resources. The optimal digestion hypothesis suggests that tortoises should process ingesta in ways that regulate assimilation rate. Finally, the cost-of-switching hypothesis suggests that herbivores, like the desert tortoise, should avoid switching food types to avoid negatively affecting the microbe community responsible for fermenting plants into energy and nutrients. Combining hypotheses into a resource acquisition theory leads to novel predictions that are generally supported by data presented here. Testing hypotheses, and synthesizing test results into a theory, provides a robust scientific alternative to the popular use of untested hypotheses and unanalyzed data to assert the needs of species. The scientific approach should focus on hypotheses concerning anthropogenic modifications of the environment that impact physiological processes ultimately important to population phenomena. We show how measurements of such impacts as nutrient starvation, can cause physiological stress, and that the endocrine mechanisms involved with stress can result in disease. Finally, our new syntheses evince a new hypothesis. Free molecules of the stress hormone corticosterone can inhibit immunity, and the abundance of "free corticosterone" in the blood (thought to be the active form of the hormone) is regulated when the corticosterone molecules combine with binding globulins. The sex hormone, testosterone, combines with the same binding globulin. High levels of testosterone, naturally occurring in the breeding season, may be further enhanced in populations at high densities, and the resulting excess testosterone may compete with binding globulins, thereby releasing corticosterone and reducing immunity to disease. This sequence could result in physiological and pathological phenomena leading to population cycles with a period that would be essentially impossible to observe in desert tortoise. Such cycles could obscure population fluctuations of anthropogenic origin.

Nearly 1500 malaria cases occur each year in the United States; approximately 60% are among U.S. travelers. Despite the availability of sophisticated medical care, malaria-related deaths continue to occur. The authors reviewed all 185 fatal cases between 1963 and 2001 that were reported to the National Malaria Surveillance System: 123 (66.5%) occurred among U.S. travelers, and of these, 114 (92.7%) were attributed to Plasmodium falciparum. Failure to take or adhere to recommended chemoprophylaxis, to promptly seek medical care for post-travel illness, and to promptly diagnose and treat suspected malaria all contributed to fatal outcomes. Health care providers need to take a travel history, obtain a blood film for suspected malaria, and use the 24-hour malaria management advice available through the Centers for Disease Control and Prevention (CDC) Malaria Hotline (770-488-7788) or the CDC Malaria Web site (http://www.cdc.gov/Malaria). Hospitals must maintain intravenous quinidine gluconate on formulary because it is the only drug available to treat severe malaria in the United States.

The monoterpenes limonene and perillyl alcohol are undergoing clinical evaluation in cancer patients. In this paper, we report the chemical synthesis, characterisation, and quantitation in patients' plasma of a novel human metabolite of limonene, which is identified as an isomer of perillic acid. The synthesis of R-perillic acid is also described, because previous reports on the activity of perillic acid against isoprenylation enzymes refer to the S-enantiomer, although it is the R-enantiomer which is the metabolite of R-limonene. The above monoterpenes, with several related compounds, were assayed for inhibitory activity towards the isoprenylation enzymes in rat brain cytosol. Although R- and S-limonene are only weak inhibitors of the isoprenylation enzymes, their major metabolites, perillic acid and perillyl alcohol, are more potent inhibitors, with IC50 values in the low mM range. The metabolites possess greater activity towards the geranylgeranyltransferase type I enzyme than farnesyltransferase, while the novel metabolite displays IC50 values similar to those of perillic acid suggesting that it may contribute to the in vivo activity of limonene.

A novel diphosphate mimic, the 2,3,6-trifluoro-5-hydroxy-4-nitrophenoxy group (1), has been employed as the template in the solid-phase synthesis of novel farnesyl transferase inhibitors using the Mitsunobu reaction. The most potent inhibitor (farnesyloxy-5-hydroxy-2,3,6-trifluoro-4-nitrobenzene) displayed an IC50 of 6.3 microM versus farnesyl transferase.

The effectiveness of mefloquine to prevent malaria caused by Plasmodium falciparum is influenced by the sensitivity of the malaria parasites to this drug. Concern has been raised that resistance to mefloquine may develop in sub-Saharan Africa as has been observed in Southeast Asia. Case reports, along with blood smears to confirm the diagnosis and blood samples to determine the mefloquine concentration, were provided on any Peace Corps volunteer serving in sub-Saharan Africa who was diagnosed with malaria. We defined prophylaxis failures probably due to mefloquine resistance as patients with P. falciparum malaria confirmed at the Centers for Disease Control and Prevention, reported compliance with prophylaxis, no ingestion of mefloquine between date of illness onset and date of blood drawing, and a mefloquine level > or = 620 ng/ml in blood drawn within five days of onset of illness. Between January 1, 1991 and September 6, 1996, 44 (31%) of 140 volunteers with confirmed P. falciparum had blood drawn within five days of onset of illness. Twenty-nine (66%) had not fully complied with prophylaxis. Five of 15 prophylaxis failures in four countries had mefloquine levels > or = 620 ng/ml. Failure of mefloquine prophylaxis is primarily due to noncompliance. Evidence of probable resistance to mefloquine among strains of P. falciparum was found in five Peace Corps volunteers in sub-Saharan Africa. Clusters of well-documented prophylaxis failures need to be followed-up by therapeutic in vivo studies to document parasite resistance to mefloquine. Reduced sensitivity to mefloquine does not (yet) appear to be a significant problem in sub-Saharan Africa.

Problem/condition: Malaria is caused by one of four species of Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae) and is transmitted by the bite of an infective female Anopheles sp. mosquito. Most malaria cases in the United States occur among persons who have traveled to areas that have ongoing transmission. However, cases are transmitted occasionally through exposure to infected blood products, by congenital transmission, or by local mosquito-borne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations., Reporting Period Covered: Cases with onset of illness during 1992., Description of System: Malaria cases were identified at the local level (i.e., by healthcare providers or through laboratory-based surveillance). All suspected cases were confirmed by slide diagnosis and then reported to the respective state health department and to CDC., Results: CDC received reports of 910 cases of malaria that had onset of symptoms during 1992 among persons in the United States and its territories. In comparison, 1,046 cases were reported for 1991, representing a decrease of 13% in 1992. P. vivax, P. falciparum, P. malariae, and P. ovale were identified in 51%, 33%, 4%, and 3% of cases, respectively. The species was not identified in the remaining 9% of cases. The number of reported malaria cases that had been acquired in Africa by U.S. civilians decreased 38%, primarily because the number of P. falciparum cases declined. Of U.S. civilians whose illnesses were diagnosed as malaria, 81% had not taken a chemoprophylactic regimen recommended by CDC. Seven patients had acquired their infections in the United States. Seven deaths were attributed to malaria., Interpretation: The decrease in the number of P. falciparum cases in U.S. civilians could have resulted from a change in travel patterns, reporting errors, or increased use of more effective chemoprophylaxis regimens., Actions Taken: Additional information was obtained concerning the seven fatal cases and the seven cases acquired in the United States. Malaria prevention guidelines were updated and disseminated to health-care providers. Persons traveling to a malaria-endemic area should take the recommended chemoprophylaxis regimen and use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently develops a fever or influenza-like symptoms should seek medical care, which should include a blood smear for malaria. The disease can be fatal if not diagnosed and treated at an early stage of infection. Recommendations concerning prevention and treatment of malaria can be obtained from CDC.

The consensus DNA sequence for binding of the Escherichia coli cyclic AMP receptor protein (CRP) has two symmetrically related inverted recognition elements TGTGA:TCACA, separated by a variable spacer, normally 6 bp long. We have shown that the CRP-cAMP complex, when bound to synthetic binding sites with an extended 8 bp spacer segment, induces an increase in the DNA circular dichroism (CD). The CD change at lambda > 275 nm agrees with the shift of approximately one helical turn of DNA into A-like form. The B-conformation is preserved for CRP binding sites similar to that in the lac and uxaCA promoters with 6 bp spacers. Another effect accompanying DNA binding is a dramatic increase of the negative CD magnitude in the spectral region of the ligand cAMP, at lambda < 272 nm. This effect is observed when CRP binds to specific sites with 6 or 8 bp spacers as well as to non-specific DNA. We reason that the A-like form arises by compressing and unwinding the DNA in CRP-DNA complexes having 8 bp central spacers. This serves to maintain a fixed length and twisting angle and is controlled by the protein's relatively rigid frame. This model is consistent with the observation that some binding sites with 6 bp spacers may also show the CD increase inherent to the sites with the extended 8 bp spacers. These 6 bp spacers are characterized by an increased twisting angle that requires their unwinding to bind to CRP. We propose that a mutual adaptation between CRP and binding sites by local untwisting and a B-->A-like transition in the DNA is of general importance and may occur in other protein-DNA complexes, such as the complex of RNA polymerase with promoter DNA.

While classifying protein binding DNA sequences of the type GTGNxCAC, based on the size of Nx [Shumilov, Mol. Biologya (Engl. Transl.) 21 (1987) 168-187], we had previously found that the cyclic AMP receptor protein (CRP)-binding sites found in the Escherichia coli genome are of at least two classes: (i) those with a conventional 6-bp spacer (N6) and (ii) those with a potential 8-bp spacer (N8) [Barber and Zhurkin, J. Biomol. Struct. Dyn. 8 (1990) 213-232]. In this paper, we present the first experimental evidence that CRP binds to DNA with an N8 spacer with relatively high affinity, as measured by gel electrophoresis of CRP-DNA complexes. We have tested two types of N8 spacers: A+T-rich and G+C-rich. Compared with the affinity of CRP for a reference site with an N6 spacer, the binding strength of CRP toward an A+T-rich N8 sequence is lower and that toward a G+C-rich N8 site is comparable. Just like DNA sites with N6 spacers, those with N8 spacers utilize both halves of the symmetrical protein recognition sequences, TGTGA and TCACA. Because of the increased number of nucleotides in the N8 spacer, the two recognition sequences in DNA will have an increased distance and a helical twist between them. These would cause displacement of the two recognition sequences with respect to the two symmetrically located alpha-helices of the CRP dimer, if there is no change in the DNA conformation.(ABSTRACT TRUNCATED AT 250 WORDS)

A Ni(2+)-binding protein (pNiXa, 45 kD, pI 8.5) discovered in Xenopus embryos, was isolated from oocytes. Based on amino acid sequences, pNiXa belongs to the serpin superfamily and shows identity to the cDNA sequence of Ep45, an estrogen-regulated hepatic serpin that contains an (HX)n-motif found in eukaryotic transcription factors. Nondenatured pNiXa, purified by Ni-affinity chromatography, inhibited bovine alpha-chymotrypsin. The presence of pNiXa in embryos when they are susceptible to Ni2+, the high avidity of pNiXa for Ni2+, and the (HX)n-motif point to pNiXa as a molecular target of Ni(2+)-teratogenesis.

Insecticide bioassays and biochemical microtitre assays were compared for detection of resistance to the organophosphate insecticides malathion and fenitrothion, using inbred laboratory strains of malaria vectors Anopheles albimanus Wiedemann, An.arabiensis Patton and An.stephensi Liston. With susceptible mosquitoes, the LT100 values determined from bioassays corresponded closely with times taken to abolish the activity of acetylcholinesterase activity in biochemical assays: approximately 2 h for malathion and 3 h for fenitrothion. Resistant strains of all three anophelines showed longer survival correlated with prolonged acetylcholinesterase activity. An.albimanus strains with insensitive acetylcholinesterase survived bioassays with discriminating doses of 1 h exposure to 5% malathion or 1% fenitrothion and were judged as resistant. It is concluded that enzyme-specific microassays provide a reliable means of detecting resistant individuals, with practical advantages over bioassays which do not reveal the resistance mechanism and require large numbers of healthy mosquitoes.

To investigate the intrinsic bending of DNA at sites where proteins bind, we analyzed catabolite gene activator protein (CAP) binding sites and various operators from the viewpoint of DNA bending flexibility. Theoretical conformational analysis. DNase I digestion and x-ray crystallography data indicate that bending of B-DNA is highly anisotropic and sequence-dependent. Certain dimers prefer to bend into the major groove ("major-philic") and others prefer to bend into the minor groove ("minor-philic" dimers). From these data we considered TA, CG, CA:TG and GG:CC as major-philic dimers and AT,AA:TT and GT:AC as minor-philic ones. Analysis of 31 CAP binding sites has identified strong major-philic tendencies 5-7 base pairs (bp) away from the center. In addition, we found minor-philic poly-A tracts extending 4-5 bp away from the proposed major-philic bends. Finally, to analyze the central regions we followed the lead of Shumilov and classified the DNA sites by their spacer lengths [V.Y. Shumilov, Mol. Biol. (Mosk) 21, 168-187 (1987)]. In this way, we identified two subsets of CAP binding sites: one with 6 bp between the TGTGA:TCACA consensus boxes (N6-set) and one with 8 central bp (N8-set). We discovered that the dimer at the center of an N6-set site was usually major-philic, whereas at the center of an N8-set site more often minor-philic. Analysis of phages 434, P22 lambda and trp operators revealed similar results. In conclusion, our data show that CAP binding sites have major-philic and minor-philic dimers at specific positions; the location of these dimers may facilitate wrapping of DNA around CAP. A similar pattern is seen in nucleosomes.

Reverse transcriptase (RT) plays an essential role in the life cycle of the human immunodeficiency viruses (HIV). A better understanding of this enzyme, and its two catalytic functions, the DNA polymerase and the RNase H, could lead to the development of new drugs that would specifically block HIV replication. The available genetic, sequence, biochemical, and immunological data on the reverse transcriptase of HIV-1 constrain the possible structure of the DNA polymerase domain. The purpose of this review is to correlate the data and to discuss, in light of that data, a model for the structure of the polymerase domain. In this model, the polymerase domain is approximately 50 to 60 A in diameter with a 20 A opening to accommodate the nucleic acid duplex. The most evolutionarily conserved region of RT (amino acids 20-190 of HIV-1 RT) is proposed to form the inner surface of the 20 A opening to which the nucleic acid hemiduplex is bound.

Here we present the SequenceEditingAligner system for editing multiple, aligned genetic sequences. This is an interactive multi-window color system that displays more than 3500 nucleotides or amino acids. The system handles nucleic acid or protein sequences with or without secondary structure data. More than 300 sequences, each more than 1500 elements in length, may be analyzed together. With the system scientists can classify elements, align sequences, edit them, find consensus patterns, and simultaneously generate oligomer frequency histograms and other statistics.

The synthesis rates of ribonuclease III (RNase III) and Era proteins are relatively low, and expression of the era gene is translationally coupled with expression of the rnc gene. Expression of both genes is negatively controlled by RNase III itself. We have constructed plasmids that overproduce RNase III and/or Era proteins under the control of the lambda PL promoter. A plasmid with the rnc gene under PL control expresses RNase III at levels greater than 40% of total cellular protein. Another plasmid with the era gene under PL control and a modified translation-initiation signal produces up to 80% of total cell protein as Era. Each protein has been purified using simple and rapid procedures. Purified RNase III protein specifically processes mRNA transcripts containing known RNase III sites. The purified Era protein binds GDP and GTP and has GTPase activity. Kinetic analysis shows that one molecule of GTP or GDP is bound/Era peptide with a Kd of 5.5 microM for GTP binding and 1.0 microM for GDP binding. The Km of the Era GTPase is 9.0 microM, and the maximum catalyzed rate of GTP hydrolyzed/min/mol of Era protein at 37 degrees C is 9.8 mmol.

1. Optimum conditions are described for a simple, rapid microplate assay that measures glutathione s-transferase (GST) activity accurately and precisely in small portions of single mosquito homogenates. 2. Up to 10 assay replicates were possible for individual adults and larvae. Concentration of GST activity in the head/thorax region allows blood-fed mosquitoes with abdomens removed to be used in assays. 3. The method allows the use of GST activity as a biochemical character in comparative studies of populations. 4. The microplate assay detects elevated GST activities associated with DDT resistance in Anopheles arabiensis.

A ring-infected erythrocyte surface antigen (RESA) has been detected by modified immunofluorescence assay in erythrocytes infected with the simian malaria parasite, Plasmodium fragile. This RESA, of Mr 95,000, shares many characteristics with the RESA initially found in the human malaria parasite P. falciparum. Both antigens are found in the membrane of erythrocytes infected with young asexual parasite stages, in merozoite-enriched preparations, and in parasite culture supernatant. Since the RESA of P. falciparum has been shown to confer protective immunity and since P. fragile infection of rhesus monkeys mimics P. falciparum infection in humans, the finding of a RESA in P. fragile underlines the importance of this species as an animal model for antimalarial vaccines.

An enzyme-linked immunosorbent assay (ELISA) was developed to detect antibody in human sera to a synthetic peptide, Asn-Ala-Asn-Pro (NANP)3, derived from the repeating amino acid sequence found in the surface circumsporozoite protein of Plasmodium falciparum sporozoites. One hundred four sera from U.S. residents were used to determine a cut-off value for reactivity. Test sera were considered reactive when the absorbance was greater than that at the 95th percentile of the control sera. Sera from 112 Kenyans living in an area of holoendemic malaria transmission were tested. Of the total number of sera, 65% had detectable antibody to (NANP)3. The percentage of reactive sera increased from 41% in sera from children under 4 years of age to 85% in sera from adults 20 to 39 years of age. The high exposure to malaria parasites of the Kenyans was reflected in indirect fluorescent antibody assay titers to blood stage P. falciparum parasites. All of the Kenyan sera had antibody present at titers greater than 1:256.

A test system that uses infective gametocytes from in vitro cultures was developed for evaluating the sporontocidal activity of antimalarial compounds. In evaluating the system, pyrimethamine and cycloguanil (dihydrofolate reductase inhibitors) and primaquine (8-aminoquinoline) were tested against pyrimethamine-sensitive and pyrimethamine-resistant strains of Plasmodium falciparum. The drugs were administered to Anopheles either in a blood meal containing infective gametocytes or in a noninfective meal 2-4 days later. The mosquitoes were dissected 9-10 days after they received the infective blood meal, and the sporontocidal effect of the drugs was evaluated by the number of oocysts found in the gut. Both cycloguanil and pyrimethamine had marked sporontocidal activity. The susceptibility pattern of the strains to the sporontocidal effect of pyrimethamine and cycloguanil was similar to the susceptibility of their asexual blood stages in vitro to the schizontocidal effect of the compounds. The sporontocidal effect was observed only when the compounds were administered at the same time as the infective blood meal, but not when they were given 2-4 days later. No sporontocidal activity was observed with primaquine. This system permits more reliable quantitative observations than have been possible with previous methods.

Certain DNA-binding proteins that regulate gene expression contain single or multiple copies of short polypeptide sequences, approximately 30 residues long, consisting of combinations of four Cys or His residues at defined spacing, so that Zn++ is complexed in tetrahedral coordination with the respective thiol-sulfur and/or imidazole-nitrogen atoms. The Zn++ ion evidently serves as a strut that stabilizes folding of the domain into a 'finger-loop', which is capable of site-specific binding to double-stranded DNA. This article reviews the evidence (a) that finger-loop domains have been highly conserved during evolution, (b) that they furnish one of the fundamental mechanisms for regulating gene expression, and (c) that a metal ion (e.g., Zn++) is required for binding of finger-loops to DNA and for their biological functions. The authors' search of amino acid sequences of 38 transforming proteins identified possible finger-loop domains in the myc, fms, fps, raf-1, rfp, src, syn, yes, erbA, int-1, and TGF-alpha gene-products. The search incidentally revealed possible finger-loop domains in human insulin receptor, which may provide a mechanistic explanation for recent observations that insulin, after binding to its cell surface receptor, is translocated to hepatocyte nuclei and becomes bound to chromatin. Zn++-coordination sites in finger-loop domains are proposed as potential targets for metal toxicity; substitution of Ni++, Co++, or Cd++ for Zn++ in finger-loops of transforming proteins is suggested as an hypothetical mechanism for metal carcinogenesis.

A high-performance liquid chromatographic method using oxidative electrochemical detection has been developed for selective and sensitive quantification of the antimalarial drug amodiaquine and three of its metabolites in the blood of dosed individuals. The method requires only one extraction step and has detection limits of 1 ng/ml for amodiaquine and its metabolites desethylamodiaquine and bisdesethylamodiaquine and 3 ng/ml for 2-hydroxydesethylamodiaquine. Minor modification of the mobile phase preserves the chromatographic separation and allows ultraviolet spectroscopic detection, which, although appreciably less sensitive, permits monitoring of levels of amodiaquine and the three metabolites in blood and urine samples if an electrochemical detector is unavailable. Levels of amodiaquine and the three metabolites were determined for two volunteers undergoing a nine-week chemoprophylactic regimen in connection with travel to a malarious area. Data are included to compare the in vitro antimalarial activities against three strains of Plasmodium falciparum of amodiaquine and the three metabolites considered.

Sequentially collected sera from Mongolian jirds (Meriones unguiculatus) infected with Brugia malayi and B. pahangi were tested for antibodies to homologous and heterologous antigens by the enzyme-linked immunosorbent assay (ELISA). Titers were less than 1:100 prior to infection and rose rapidly (within 2 weeks). Peak titers were observed prior to patent microfilaremia, and high titers persisted during infection. Use of the homologous antigen did not increase sensitivity or specificity of the ELISA. In fact, B. malayi-infected jirds demonstrated higher titers to the heterologous antigen, B. pahangi, than to the homologous antigen. Fractionation of B. malayi antigen over a wide pH range using isoelectric focusing did not eliminate cross-reactions, but the reactions of 20 B. malayi sera and 20 B. pahangi sera tested more strongly to specific fractions, particularly in the lower pH range.