Household-Contact Investigation for Detection of Tuberculosis in Vietnam.

BACKGROUND: Active case finding is a top priority for the global control of tuberculosis, but robust evidence for its effectiveness in high-prevalence settings is lacking. We sought to evaluate the effectiveness of household-contact investigation, as compared with standard, passive measures alone, in Vietnam. METHODS: We performed a cluster-randomized, controlled trial at clinics in 70 districts (local government areas with an average population of approximately 500,000 in urban areas and 100,000 in rural areas) in eight provinces of Vietnam. Health workers at each district clinic or hospital were assigned to perform either household-contact intervention plus standard passive case finding (intervention group) or passive case finding alone (control group). In the intervention districts, household contacts of patients with positive results for tuberculosis on sputum smear microscopy (smear-positive tuberculosis) were invited for clinical assessment and chest radiography at baseline and at 6, 12, and 24 months. The primary outcome was the cumulative incidence of registered cases of tuberculosis among household contacts of patients with tuberculosis during a 2-year period. RESULTS: In 70 selected districts, we enrolled 25,707 household contacts of 10,964 patients who had smear-positive pulmonary tuberculosis. In the 36 districts that were included in the intervention group, 180 of 10,069 contacts were registered as having tuberculosis (1788 cases per 100,000 population), as compared with 110 of 15,638 contacts (703 per 100,000) in the control group (relative risk of the primary outcome in the intervention group, 2.5; 95% confidence interval [CI], 2.0 to 3.2; P<0.001); the relative risk of smear-positive disease among household contacts in the intervention group was 6.4 (95% CI, 4.5 to 9.0; P<0.001). CONCLUSIONS: Household-contact investigation plus standard passive case finding was more effective than standard passive case finding alone for the detection of tuberculosis in a high-prevalence setting at 2 years. (Funded by the Australian National Health and Medical Research Council; ACT2 Australian New Zealand Clinical Trials Registry number, ACTRN12610000600044 .).

Post-treatment Mortality Among Patients With Tuberculosis: A Prospective Cohort Study of 10 964 Patients in Vietnam.

BACKGROUND: Tuberculosis is the leading infectious cause of death. Steep reductions in tuberculosis-related mortality are required to realize the World Health Organization's "End Tuberculosis Strategy." However, accurate mortality estimates are lacking in many countries, particularly following discharge from care. This study aimed to establish the mortality rate among patients with pulmonary tuberculosis in Vietnam and to quantify the excess mortality in this population. METHODS: We conducted a prospective cohort study among adult patients treated for smear-positive pulmonary tuberculosis in 70 clinics across Vietnam. People living in the same households were recruited as controls. Participants were re-interviewed and their survival was established at least 2 years after their treatment with an 8-month standardized regimen. The presence of relapse was established by linking identifying data on patients and controls to clinic registries. Verbal autopsies were performed. The cumulative mortality among patients was compared to that among a control population, adjusting for age and gender. RESULTS: We enrolled 10964 patients and 25707 household controls. Among enrolled tuberculosis patients, 9% of patients died within a median follow-up period of 2.9 years: 342 (3.1%) during treatment and 637 (5.8%) after discharge. The standardized mortality ratio was 4.0 (95% confidence interval 3.7-4.2) among patients with tuberculosis, compared to the control population. Tuberculosis was the likely cause of death for 44.7% of these deceased patients. CONCLUSIONS: Patients treated for tuberculosis had a markedly elevated risk of death, particularly in the post-treatment period. Interventions to reduce tuberculosis mortality must enhance the early detection of drug-resistance, improve treatment effectiveness, and address non-communicable diseases.

Analysis of KRAS and NRAS Gene Mutations in Arab Asian Children With Acute Leukemia: High Frequency of RAS Mutations in Acute Lymphoblastic Leukemia.

BACKGROUND: KRAS and NRAS gene mutations are frequently observed in childhood leukemia. The objective of this study was to determine the frequency of RAS mutations and the association between RAS mutations and other genetic aberrations in Arab Asian children with acute lymphoblastic leukemia (ALL) or acute myeloid leukemia (AML). METHODS: Diagnostic samples of 485 patients (<18 years) with acute leukemia from Iraq and Jordan were obtained, using Flinders Technology Associates filter papers. Polymerase chain reaction and direct sequencing were performed in Japan. RESULTS: RAS mutations were detected in 86/318 (27%) of ALL cases and 35/167 (21%) of AML cases. The frequency of NRAS mutation was similar to that of KRAS mutation in ALL. Two RAS mutations were detected in nine patients. Among 264 Iraqi patients with ALL, RAS mutation was significantly associated with lower initial white blood cell count. Of 57 patients with chimeric transcripts, only two patients with either TEL-AML1 or E2A-PBX1 had KRAS mutation. The frequency of NRAS mutation was four times higher than that of KRAS mutation in AML. FAB-M4 and M5 subsets were associated with RAS mutation. Among 134 Iraqi patients with AML, 18 patients had RAS mutations and other genetic aberrations. In particular, 9 of 25 (36%) with MLL-rearrangement had RAS mutations. CONCLUSION: The prevalence of oncogenic RAS mutations was higher among Arab Asian children than in other countries. RAS mutations in AML were found to coexist with other genetic aberrations, particularly MLL rearrangement.

Frequent coexistence of RAS mutations in RUNX1-mutated acute myeloid leukemia in Arab Asian children.

BACKGROUND: RUNX1 mutation plays an important role in adult leukemic transformation. However, its contribution to the development of childhood leukemia remains unclear. In the present study, we analyzed point mutations of RUNX1 gene in children and adolescents with acute myeloid leukemia (AML) from Iraq and Jordan. PROCEDURE: Bone marrow and/or peripheral blood samples were collected from 178 patients of Arab Asian ethnicity (aged ≤17 years) newly diagnosed with AML: 145 samples from Iraq and 33 samples from Jordan. Direct DNA sequencing was performed on six genes including RUNX1 gene (exons 3-8). RESULTS: RUNX1 point mutations were identified in 10 (5.6%) of 178 patients. One patient possessed biallelic mutations of RUNX1 gene. C-terminal area was the predominant site of RUNX1 mutations (eight in C-terminal and two in N-terminal). Patients with RUNX1 mutations were significantly older than those with wild-type of the gene. Additionally, AML M0 subtype was more frequently found in patients with RUNX1 mutations. Both RUNX1 mutations and RAS mutations were identified in 4 of 10 children. Three patients with RUNX1 mutation had FLT3-ITD. On the other hand, 36 (21.4%) and 25 (14.9%) of 168 patients with wild-type of the gene had a RAS mutation and FLT3-ITD, respectively. Eight of 10 patients with RUNX1 mutations died of hematological relapse. CONCLUSION: The incidence of RUNX1 mutations in Arab Asian children and adolescents with AML was 5.6%. Further studies are required to clarify whether RAS mutations contribute to the development of pediatric AML associated with RUNX1 mutations.

Total serum cortisol level is low in children with severe dengue shock syndrome.

Dengue shock syndrome (DSS) is a potentially critical and life-threatening concern, especially in children of tropical countries. The serum cortisol levels in severe DSS or later stages of DSS are limited references. We prospectively studied an association between of serum cortisol as well as interleukin levels and the severity of DSS in pediatric patients. A prospective cross-sectional study of 35 consecutive DSS cases (3 months to 16 years old) admitted to our institution from July 1, 2019, to June 30, 2020 was conducted. Serum cortisol, IL-6, and IL-10 were measured at T0 (shock recognition) and T12 (12 hours after T0); their values were presented as median and interquartile ranges (25%-75%). Severe DSS included patients with impalpable pulses or systolic blood pressure < 70 mmHg, recurrent shock, and prolonged shock. In contrast, non-severe DSS presented circulatory failure without any features of severe DSS. A total of 8 (22.8%) severe DSS patients expressed the cortisol (T0) significantly lower compared to the non-severe DSS group (7.3 µg/dl versus 14.3 µg/dl, p=0.008). In severe DSS, there was a minimal change in cortisol levels between T0 and T12 (7.3 µg/dl and 4.7 µg/dl p>0.05), whereas the decrease is significant in their counterparts (14.3 µg/dl to 5.6 µg/dl, p<0.005). Additionally, there were moderate correlations between IL-6 (T0), IL-10 (T0), IL-10 (T12) and total fluid requirement (Spearman's rho = 0.47, 0.4, and 0.36, respectively; p<0.05). Our study demonstrated that adrenal dysfunction was present in patients with severe and non-severe DSS, as noted by cortisol level at T12. In addition, IL-6 and IL-10 levels are correlated with the total fluid requirement, which is a marker of DSS severity. Further studies could reveal how adrenal dysfunction in pediatric patients with DSS can affect outcomes and the potential roles of interleukin levels in fluid management strategy.

High Levels of Treatment Success and Zero Relapse in Multidrug-Resistant Tuberculosis Patients Receiving a Levofloxacin-Based Shorter Treatment Regimen in Vietnam.

Vietnam has been using a levofloxacin-based shorter treatment regimen (STR) for rifampicin resistant/multidrug-resistant tuberculosis (RR/MDR-TB) patients since 2016 on a pilot basis. This regimen lasts for 9-11 months and is provided to RR/MDR-TB patients without second-line drug resistance. We report the treatment outcomes and factors associated with unsuccessful outcomes. We conducted a cohort study involving secondary analysis of data extracted from electronic patient records maintained by the national TB program (NTP). Of the 302 patients enrolled from April 2016 to June 2018, 259 (85.8%) patients were successfully treated (246 cured and 13 'treatment completed'). Unsuccessful outcomes included: treatment failure (16, 5.3%), loss to follow-up (14, 4.6%) and death (13, 4.3%). HIV-positive TB patients, those aged ≥65 years and patients culture-positive at baseline had a higher risk of unsuccessful outcomes. In a sub-group of patients enrolled in 2016 (n = 99) and assessed at 12 months after treatment completion, no cases of relapse were identified. These findings vindicate the decision of the Vietnam NTP to use a levofloxacin-based STR in RR/MDR-TB patients without second-line drug resistance. This regimen may be considered for nationwide scale-up after a detailed assessment of adverse drug events.

Molecular evolution caught in action: gene duplication and evolution of molecular isoforms of prothrombin activators in Pseudonaja textilis (brown snake).

BACKGROUND: The evolution of structurally and functionally similar proteins with highly diverse physiological roles within a single organism is of great interest. Australian elapid snakes offer an excellent opportunity to study the molecular evolution of prothrombin activators. Venom from Pseudonaja textilis contains pseutarin C, a group C prothrombin activator. Its enzymatic subunit is structurally and functionally similar to mammalian factor (F) Xa, whereas its non-enzymatic subunit is similar to FVa. As vertebrates, the snakes also contain a system to activate prothrombin in their own blood during injury. These hemostatic factors are produced in the liver. RESULTS: Here we describe the presence of two molecular forms of FX expressed in the liver of P. textilis. Both isoforms have molecular signatures and domain architecture of FX. However, one isoform shows approximately 94% sequence identity with the snake FX from Tropidechis carinatus, whereas the other is much closer (90% identity) to the catalytic subunit of pseutarin C (PCCS). Real-time polymerase chain reaction reveals that the latter isoform is expressed approximately 56 000 times lower in the liver of P. textilis. However, the isoforms are not expressed in the venom gland. CONCLUSION: A detailed analysis of deletions and insertions along with the sequence indicates that the second isoform is an intermediate caught in the evolution of venom prothrombin activator from the blood coagulation FX. Thus, this isoform represents a 'molecular fossil' and reveals the likely evolutionary path of recruitment of FX in the venom gland.

A study of Folch-Pi apoprotein. II. Relation between polymerization state and conformation.

A comparison of the conformation of Folch-Pi apoprotein in organic solvent and in aqueous solutions has been made by ESR, infrared and circular dichroism spectroscopy studies. Electrophoresis and ultracentrifugation have been carried out in order to correlate molecular weight and charge of the molecule with its conformation. It appears that the protein is monomeric in organic solution. In water, only one component is present but the molecules behave as a polydisperse system of associating molecules. Hydrophobic interacitons seem to be important for this polymerisation which does not appear to be accompanied by the formation of beta-structure. After the transfer of the protein from organic solution to water, the ESR spectra of the protein labelled on the free SH groups show an heterogeneity in the motional environment of the label which permits to assume that different areas of association exist in the polymeric molecule.

Field evaluation of the establishment potential of wMelPop Wolbachia in Australia and Vietnam for dengue control.

BACKGROUND: Introduced Wolbachia bacteria can influence the susceptibility of Aedes aegypti mosquitoes to arboviral infections as well as having detrimental effects on host fitness. Previous field trials demonstrated that the wMel strain of Wolbachia effectively and durably invades Ae. aegypti populations. Here we report on trials of a second strain, wMelPop-PGYP Wolbachia, in field sites in northern Australia (Machans Beach and Babinda) and central Vietnam (Tri Nguyen, Hon Mieu Island), each with contrasting natural Ae. aegypti densities. METHODS: Mosquitoes were released at the adult or pupal stages for different lengths of time at the sites depending on changes in Wolbachia frequency as assessed through PCR assays of material collected through Biogents-Sentinel (BG-S) traps and ovitraps. Adult numbers were also monitored through BG-S traps. Changes in Wolbachia frequency were compared across hamlets or house blocks. RESULTS: Releases of adult wMelPop-Ae. aegypti resulted in the transient invasion of wMelPop in all three field sites. Invasion at the Australian sites was heterogeneous, reflecting a slower rate of invasion in locations where background mosquito numbers were high. In contrast, invasion across Tri Nguyen was relatively uniform. After cessation of releases, the frequency of wMelPop declined in all sites, most rapidly in Babinda and Tri Nguyen. Within Machans Beach the rate of decrease varied among areas, and wMelPop was detected for several months in an area with a relatively low mosquito density. CONCLUSIONS: These findings highlight challenges associated with releasing Wolbachia-Ae. aegypti combinations with low fitness, albeit strong virus interference properties, as a means of sustainable control of dengue virus transmission.

Application of the World Health Organization system for HIV infection in a cohort of homosexual men in developing a prognostically meaningful staging system.

OBJECTIVE: Validation of a modified version of the recently proposed World Health Organization (WHO) staging system for HIV infection and disease in a cohort of homosexual men. METHODS: Five hundred and thirty HIV-positive men followed for a median of 51 months (range, 1-98 months) were eligible for analysis. Subjects were classified into stages at their first seropositive visit and at all subsequent visits. RESULTS: As of 1 April 1991, 136 subjects (26%) had progressed to stage IV of the modified WHO system on the basis of their CD4 lymphocyte counts, and 78 subjects (15%) had died. Kaplan-Meier estimates for progression to stage IV from stages I, II and III were 52.8 +/- 7.5% over 6.6 years, 58.1 +/- 7.1% over 5.9 years and 66.5 +/- 9.7% over 5.7 years (log-rank P = 0.0001). Estimated median times to stage IV were 6.4, 5.3 and 3.8 years from stages I, II and III, respectively. Estimated median times to death were 10.9, 8.2, 6.3 and 1.7 years from stages I to IV, respectively. Results remained unchanged when CD4 lymphocyte count was replaced with lymphocyte count in the laboratory axis of the staging system. CONCLUSIONS: The proposed staging scheme, based on the WHO system, provides a prognostically meaningful classification for HIV infection in a cohort of homosexual men. Furthermore, the use of absolute lymphocyte count as a valid alternative for CD4 lymphocyte count has implications for the applicability of this system in many parts of the world where diagnostic resources are limited.

Low HIV-1 proviral DNA burden detected by negative polymerase chain reaction in seropositive individuals correlates with slower disease progression.

During 1989, 316 members of a cohort of homosexual men were tested for HIV-specific DNA by the polymerase chain reaction (PCR) using a pair of gag-region primers. Of 125 HIV-seronegative subjects, 123 (98.4%) were PCR-negative while 158 (82.7%) of 191 HIV-seropositive subjects were PCR-positive. Fewer of the 33 subjects who were seropositive and PCR-negative were at Centers for Disease Control (CDC) stage IV than the seropositive, PCR-positive subjects (6 versus 25%; P = 0.030). The seropositive, PCR-negative group had higher mean CD4 counts (640 versus 490 x 10(6) cells/l; P = 0.006), higher CD4: CD8 ratios (0.92 versus 0.64; P = 0.004), lower immunoglobulin (Ig) G levels (1290 versus 1645 mg/dl; P = 0.002), lower IgA levels (168 versus 251 mg/dl; P less than 0.001), and lower C1q binding activity (8 versus 14%; P = 0.010) than the seropositive, PCR-positive subjects. The median rate of CD4 cell decline in the 3 years preceding the PCR sample was less marked in the seropositive, PCR-negative group than the seropositive, PCR-positive group (-58 versus -77 x 10(6) cells/l per year; P = 0.028). To control for duration of infection, we restricted the analysis to the subgroups of 11 seropositive, PCR-negative subjects and 34 seropositive, PCR-positive subjects who had seroconverted earlier in the cohort study. Both subgroups had similar durations of infection, yet the same pattern of differences persisted.(ABSTRACT TRUNCATED AT 250 WORDS)

Susceptibility to AIDS progression appears early in HIV infection.

To investigate whether predictors of AIDS progression are operative very early in the natural history of HIV infection, we conducted a nested case-control study within a cohort of 119 subjects who seroconverted while under observation in a prospective study of homosexual men. For each of the 18 cases who have progressed to AIDS, we randomly selected three controls who had seroconverted within 3 months of the case but who have remained AIDS-free. Cases and controls were compared with regard to laboratory and clinical parameters obtained at the time of the earliest HIV-positive result. The median duration between the estimated date of seroconversion and this first positive result was 4 months for cases and 6 months for controls. Cases exhibited lower CD4 counts (657 versus 774 x 10(6)/l; P = 0.037), lower CD4: CD8 ratios (0.98 versus 1.39; P = 0.003), higher immune complex levels (C1q binding: 25 versus 15%; P = 0.002), lower hemaglobin concentrations (14.8 versus 15.2 g/l; P = 0.011), higher immunoglobulin (Ig) A levels (272 versus 184 mg/dl; P = 0.003), and higher IgG levels (1530 versus 1300 mg/dl; P = 0.037) than controls. Cases exhibited higher CD8 counts of marginal statistical significance (732 versus 597 x 10(6)/l; P = 0.059). No differences were observed with respect to IgM levels, total lymphocyte or white blood cell counts, or the frequency of generalized lymphadenopathy. A total of 27.8% of cases but only 11.5% of controls reported one or more symptoms during the 6-month period preceding the first positive visit (P = 0.027). We conclude that laboratory and clinical abnormalities which are predictive of more rapid progression to AIDS may appear very early in HIV infection. This suggests that some of the factors responsible for more rapid disease progression are present in the host prior to or shortly after infection occurs.

Progression to AIDS and predictors of AIDS in seroprevalent and seroincident cohorts of homosexual men.

As part of an ongoing prospective study of seropositive homosexual men in Vancouver, Canada, a seroprevalent cohort of 246 subjects (i.e. duration of infection unknown) and a seroincident cohort of 102 subjects (i.e. duration of infection known) were followed a median of 63 and 45 months, respectively. Follow-up with validation utilizing record linkage with the Canadian Federal Centre for AIDS registry revealed 58 and nine cases of AIDS in the seroprevalent and seroincident cohorts, respectively, through July 1988. These data yield product limit estimates of the cumulative progression rates to AIDS at 60 months of 23.0% for the seroprevalent cohort, 13.0% for the seroincident cohort, and 21.0% for the combined groups. Univariate analyses revealed the following to be statistically and clinically significant predictors of AIDS progression: low CD4 counts, low CD4/CD8 ratios, elevated immune complexes, elevated immunoglobulin G (IgG) and immunoglobulin A (IgA) levels, and low platelet counts. Cox regression revealed that elevated IgA levels, low CD4 counts, elevated immune complexes, two or more symptoms, and more than 20 male sexual partners in high-risk areas in the 5 years prior to enrollment were independent predictors of progression to AIDS over the subsequent 5 years. A multivariate risk function based on the latter five variables delineated low-, medium- and high-risk groups whose 5-year progression rates to AIDS were 6.7, 15.6 and 64.4%, respectively. The high-risk group contained 75% of all subjects who progressed to AIDS. Only 6% of the high-risk group would have qualified for zidovudine therapy under current guidelines at the beginning of the observation period.(ABSTRACT TRUNCATED AT 250 WORDS)

Risk factors for Kaposi's sarcoma in the Vancouver Lymphadenopathy-AIDS Study.

In our ongoing cohort study of homosexual men, the ratio of new Kaposi's sarcoma (KS) cases to new opportunistic infections (OI) during the periods 1982-1985, 1986-1987, and 1988-1989 fell from 0.75 (9 KS: 12 OI) to 0.57 (12 KS:21 OI) to 0.27 (4 KS:15 OI), respectively. To examine factors associated with the development of KS as compared to OI, we compared antecedent risk factors in 25 KS cases and 48 OI "controls." In univariate analyses, several classical HIV risk factors including numbers of sexual partners and receptive anal intercourse were higher in the KS than the OI group. The strongest associations were found with an elevated number of sex partners in high-risk areas (San Francisco, Los Angeles, and New York) in the 5 years prior to enrollment and with elevated use of nitrite inhalants. Logistic regression revealed the latter two variables and an elevated number of partners contacted in washrooms/parks to be significant, independent risk factors for KS relative to OI. Any or all of these variables could be related with early HIV infection. However, the association with early sexual contact in high-risk areas raises the more intriguing possibility that this variable is an indicator of an increased exposure either to a particular strain of HIV that is more pathogenic for KS, or, more likely, to a sexually transmitted KS cofactor that may have been more highly concentrated in these areas at this early point in the epidemic. The present study supports an independent association with use of nitrite inhalants, which could be hypothesized either to have an independent biologic effect on KS or to enhance the efficiency of transmission of the cofactor virus.

Higher socioeconomic status is associated with slower progression of HIV infection independent of access to health care.

In order to identify socioeconomic characteristics associated with slower progression of HIV infection, we conducted a nested case-control study within a cohort of 729 homosexual men. The study compared non-progressors (defined as subjects who, at a follow-up visit during the period October 1989-December 1990, had been HIV positive for at least 5 years, had a CD4 count > 0.5 x 10(9)/l, had a Karnofsky score of 100%, were at Centers for Disease Control (CDC) Stage III or less, and had never received zidovudine or prophylaxis against Pneumocystis carinii pneumonia) with rapid progressors (defined as those who had developed AIDS other than Kaposi's sarcoma within 6 years of seroconversion, or within 5 years of enrollment if already seropositive). Rapidly progressing subjects were matched to non-progressing subjects on the basis of date of enrollment if seroprevalent and date of seroconversion if seroincident. Socioeconomic data were taken from the questionnaire obtained at enrollment into the cohort during 1982-84. There were 41 subjects in each group. A significantly higher proportion of the non-progressors had annual incomes above $10,000, at enrollment (85 vs 62%; p = 0.019). Similarly, a greater proportion of the non-progressors were more likely to have finished secondary school (100 vs 84%; p = 0.020) than rapid progressors. A higher proportion of non-progressors reported employment in management and professional positions (35 vs 15%). The non-progressing group also had a significantly higher socioeconomic index based on self-reported occupation (45.1 vs 38.3; p = 0.035). The association with higher income persisted even after adjustment for baseline CD4 count and symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

In vitro pulsatile flow evaluation of a stentless porcine aortic bioprosthesis.

Suboptimal hemodynamic performance, tissue calcification, and limitation in long-term durability have been encountered clinically after aortic valve replacement with currently available bioprostheses. It is believed that some of these problems may be caused, directly or indirectly, by the stents of the bioprostheses. To address these deficiencies, the authors undertook the development of the Edwards Prima Stentless Bioprosthesis. This study was designed to evaluate the hemodynamic performance of the Edwards Prima Stentless Bioprosthesis in a pulse duplicator system. The stented Carpentier-Edwards Porcine Bioprosthesis (Baxter Healthcare Corp., Irvine, CA), which has been used in United States clinics for more than 10 years, was used as a control device. The flow fields in the vicinity of the test bioprostheses were inspected with color Doppler flow mapping. The transvalvular pressure gradients were measured invasively with a catheter and calculated with the Doppler determined velocity using a simplified Bernoulli equation. Additionally, the leakage volumes were determined with an electromagnetic flowmeter. In the Doppler flow mapping study, during systole, a central flow was observed distal to the stentless and stented bioprostheses. The central flow distal to the stentless bioprosthesis was broader than that observed distal to its stented counterpart. During diastole, no regurgitation was detected by color Doppler flow mapping in either the stentless or stented groups. The Doppler determined transvalvular pressure gradients correlated well with those measured by catheter (r = 0.990). Moreover, it was learned that the transvalvular pressure gradients of the stentless bioprosthesis were less than those of its stented counterpart, especially for the smaller sizes.(ABSTRACT TRUNCATED AT 250 WORDS)

The role of computerized video imaging in predicting adult extraction treatment outcomes.

The purpose of this study was to evaluate the accuracy of computerized video imaging in predicting the soft tissue outcome of extracting four premolars in adults. The pretreatment and posttreatment cephalometric and facial photographic records of 31 previously treated, nongrowing patients were digitized and computer-generated cephalometric VTOs and video images were compared with the known outcomes. The results showed that both the VTOs and video images were accurate enough to be used for patient education and communication, as well as for diagnosis and treatment planning. While lay people found that the predicted video images adequately resembled the actual outcomes, orthodontists were more critical, particularly of the lower lip area where variable soft tissue responses to treatment were noted.

Implantable diagnostic and therapeutic devices in children.

Many advances have been made in the use of implantable diagnostic and therapeutic devices in adults. In children the indications for and diagnostic and therapeutic value of these devices still have to be determined. Our aim is to provide an overview of the clinical use of diagnostic and therapeutic devices in children. The role of implantable loop recorders (ILR), the feasibility and safety of transvenous pacing in neonates, the value of permanent pacing in children with recurrent syncope or reflex anoxic seizures and the role of implantable cardioverter defibrillator devices are highlighted with relevant case histories.

Impact of chemical warfare with agent orange on women's reproductive lives in Vietnam: a pilot study.

During the American war in Vietnam, huge quantities of the highly toxic herbicide dioxin ('Agent Orange'), were sprayed over large areas of central and south Vietnam. In addition to polluting the environment and causing cancers and other diseases in those directly exposed to it, dioxin has caused high rates of pregnancy loss, congenital birth defects and other health problems in their children. This paper reports the findings of a pilot study in the year 2000 among 30 Vietnamese women whose husbands and/or who themselves were exposed to Agent Orange. The aim was to develop research in order to explore the impact of chemical warfare on people's lives. Using the reproductive lifeline and semi-structured interviews, information was gathered on both partners' periods of exposure to Agent Orange, pregnancy outcomes, perceived health problems of children and experiences of living with handicapped children. The women had had a high number of miscarriages and premature births. About two-thirds of their children had congenital malformations or developed disabilities within the first years of life. Most of the families were poor, aggravated by impaired health in the men, the burden of caring for disabled children, and feelings of guilt and inferiority. The plight of 'Agent Orange families' is special and should be placed in its historical and political context.