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1.
Tooth transposition is a positional interchange of two adjacent teeth. The most commonly transposed tooth is the permanent canine with either the first premolar or lateral incisor. The records of 54 subjects with transposed canines, both maxillary and mandibular, were collected. Pretreatment study models of these subjects were matched with a similar number of models from unaffected individuals. Bucco-lingual and mesio-distal tooth widths, arch depth and arch width were measured on each model. Thirty-four subjects (63 per cent) were female. Thirty-seven (68.5 per cent) of the cases involved the maxillary arch and thirty-three (89.2 per cent) of these upper arch transpositions were of the canine and first premolar. In cases involving the lower arch the canine was invariably transposed with the lateral incisor. Peg-shaped lateral incisors, supernumerary and/or congenitally absent teeth occurred in 19 subjects. There were some small, but significant differences in the dimensions of some teeth, however there were no statistically significant differences in arch depths, arch widths and most tooth dimensions in subjects with and without transposed canines. These factors do not appear to be related to the development of canine transposition.  相似文献   

2.
Hepatitis G virus (HGV) is prevalent in patients with chronic liver disease and has been previously detected in liver specimens. However, it is unknown whether the virus is replicating in the liver or is simply a contaminant from serum. We sought to determine whether HGV was hepatotropic and to determine whether coinfection with HGV and hepatitis C virus (HCV) influenced the level of either virus. Virus was quantitated using branched DNA (bDNA) assay for both HGV and HCV in the liver explants and pretransplant serum samples from 30 transplant recipients: Group I, HGV/HCV coinfection (n = 10); group II, HCV infection alone, (n = 8); group III, HGV alone (n = 12). In patients with coinfection HCV (RNA) titers in liver were consistently higher than those for HGV RNA (median 1.13 x 10(8) and 360,000 Eq/g respectively, P < .01). The ratio of liver/serum viral RNA was significantly higher for HCV than for HGV (median 129 and 0.3 respectively, P < .01). Levels of HCV RNA were similar in patients with HCV infection alone versus those with HGV/HCV coinfection (median; liver = 1.15 x 10(7) vs. 1.13 x 10(8) Eq/g, serum = 500,000 vs. 200,000 Eq/mL) and levels of HGV RNA in liver and serum were similar in patients with HGV infection alone compared to those with HGV/HCV coinfection (median; liver = 1.2 x 10(6) vs. 4.0 x 10(5) Eq/g, serum = 4.5 x 106 vs. 2.6 x 10(6) Eq/mL). Levels of either virus appeared unaffected by the presence of an additional virus. The high ratio of HCV RNA levels in liver compared to serum is consistent with its known hepatotropism, but this pattern was not observed for HGV. The median liver/serum ratio of HGV RNA was less than unity, a finding consistent with serum contamination of liver tissue. Thus we conclude that the liver is not the main site of HGV replication.  相似文献   

3.
Hepatitis B virus (HBV) serum markers (HBsAg, anti-HBs, anti-HBc) and antihepatitis C antibody (anti-HCV) were prospectively followed in haemodialysis and CAPD patients. From January 1987 to January 1990, 185 patients on haemodialysis and 124 on CAPD were analysed. Among patients susceptible to HBV (69 on haemodialysis and 70 on CAPD), there were 17 HBsAg seroconversions on haemodialysis (0.19/patient-year) and 1 on CAPD (0.01/patient-year). A Cox proportional hazards model showed that haemodialysis treatment was the only risk factor significantly associated with HBV infection, thus suggesting transmission through the environment. Regarding hepatitis C, 83 anti-HCV-negative patients on haemodialysis and 46 on CAPD were followed. There were 18 seroconversions on haemodialysis (0.15/patient-year) and two seroconversions on CAPD (0.03/patient-year). Haemodialysis treatment was also the only risk factor significantly associated with a higher risk of HCV infection. The hazard ratio for HCV infection in haemodialysis patients was 5.7 compared to CAPD patients. Nevertheless, for one patient on CAPD treatment transfusions were the only possible source of HCV infection. In conclusion, both viruses were transmitted mainly through the haemodialysis environment, but the role of transfusions could not be excluded.  相似文献   

4.
Little is known about vertical transmission of hepatitis E virus from infected mothers to their infants. We studied eight babies born to mothers infected with hepatitis E in third trimester. One baby was icteric at birth with elevated transaminases and four babies had anicteric hepatitis. Two babies were born with hypothermia and hypoglycaemia and died within 24 h; one had massive hepatic necrosis. Hepatitis E virus RNA was detected by PCR in cord or birth blood samples of five infants. Six infants had evidence of hepatitis E infection. We conclude that hepatitis E virus is commonly transmitted from infected mothers to their babies with significant perinatal morbidity and mortality.  相似文献   

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BACKGROUND: Cavernous carotid aneurysms are generally benign entities. Certain indications exist for their treatment, however, including transient ischemic events, subarachnoid hemorrhage or risk of subarachnoid hemorrhage, epistaxis or its risk, ophthalmoplegia, pain, and progressive visual loss. We feel certain angiographic features may indicate a greater likelihood that cavernous carotid aneurysms extend into the subarachnoid space, thus making their rupture a life-threatening event. METHODS: A case report of an intracavernous carotid aneurysm, which at surgery extended into the subarachnoid space, is described. RESULTS: In this particular case, deformation of the aneurysm (waisting) as seen at angiography was in retrospect an indication that the cavernous carotid aneurysm extended into the subarachnoid space, either through the dural ring or through the eroded dural roof of the cavernous sinus. This finding was verified at surgery when the lesion was explored and trapped. CONCLUSION: Angiographic waisting of a cavernous carotid aneurysm may indicate that the aneurysm extends into the subarachnoid space. Such extension means that rupture would be a life-threatening event. While deformation of the aneurysm may be secondary to compression against the optic nerve or anterior clinoid process with an intact layer of dura overlying the aneurysm, the neurosurgeon confronted with such findings should analyze such lesions carefully and consider surgical exploration.  相似文献   

7.
OBJECTIVE: To study a possible correlate of protection in mother-to-infant transmission of HIV infection. In particular, to determine whether lack of HIV-specific T-helper (TH) function as indicated by HIV and non-HIV antigen-stimulated interleukin (IL)-2 production of mother and/or newborn peripheral blood leukocytes (PBL) is associated with mother-to-infant transmission of HIV. METHODS: PBL from 21 HIV-seropositive pregnant women and 23 cord blood leukocytes (CBL) from their offspring were studied for in vitro TH function by IL-2 production in response to HIV and non-HIV antigens. Polymerase chain reaction (PCR) and viral culture assays were performed to determine HIV infection of the infants. RESULTS: PBL from 10 out of 21 (48%) mothers and from eight out of 23 (35%) CBL samples responded to two or more out of five synthetic gp 160 envelope (env) peptides. Three of the 23 (13%) offspring were shown to be HIV-infected by PCR and/or viral culture on follow-up. All three infected infants were from a subset whose CBL did not exhibit env-specific TH immunity. CONCLUSION: Our results demonstrate that fetal T cells can be primed to HIV env determinants in utero, suggest that HIV-specific TH immunity may be protective in newborns, and provide a possible means for identifying newborns who are at risk for HIV infection.  相似文献   

8.
We have demonstrated a microfabricated single-molecule DNA sizing device. This device does not depend on mobility to measure molecule size, is 100 times faster than pulsed-field gel electrophoresis, and has a resolution that improves with increasing DNA length. It also requires a million times less sample than pulsed-field gel electrophoresis and has comparable resolution for large molecules. Here we describe the fabrication and use of the single-molecule DNA sizing device for sizing and sorting DNA restriction digests and ladders spanning 2-200 kbp.  相似文献   

9.
To study mother-to-infant transmission of GB virus C/hepatitis G virus (GBV-C/HGV), blood samples of infants born to carrier mothers were collected beginning 3 months after birth and were tested for GBV-C/HGV RNA until 1 year of age. Of 2046 mothers, 2.1% were positive for GBV-C/HGV RNA, and 25 of their infants were followed for a median of 12 months. Thirteen infants (52%) were viremic, and infection became persistent in all. Maternal GBV-C/HGV RNA levels of this group were >10(7) copies/mL. Nucleotide sequence comparison in 5 viremic mother-infant pairs revealed a homology of 93%-98.2%, and none delivered by elective cesarean section. In comparison, of the 12 uninfected infants' mothers, 10 had lower GBV-C/HGV RNA levels (mean, 5 x 10(4) copies/mL), and the remaining 2 high-titered mothers had elective cesarean section. Thus, high-titered maternal viremia and mode of delivery are closely associated with the mother-to-infant transmission of GBV-C/HGV to infants, and the infection usually becomes persistent.  相似文献   

10.
To assess the relationship between maternal human immunodeficiency virus (HIV) type 1 RNA level, other important covariates, and mother-to-infant (vertical) transmission of HIV-1, third trimester repository specimens from 160 HIV-1-seropositive women enrolled in the Mothers and Infants Cohort Study between 1986 and 1991 were assayed in batch for HIV-1 RNA. A significant association between peripheral blood HIV-1 RNA level and vertical transmission remained after controlling for CD4 cell level, duration of ruptured membranes, "hard" drug (cocaine and heroin) use, and frequency of sexual activity during pregnancy. However, the association was attenuated among women with advanced HIV infection and those with a high frequency of sexual activity during pregnancy. In these settings, interventions that target risk factors other than virus load may be particularly important for preventing vertical transmission of HIV-1.  相似文献   

11.
BACKGROUND/AIMS: Chronic graft hepatitis occurs in 20-30% adults after liver transplantation but the prevalence and causes in children are not known. In adults, hepatitis C virus infection is prevalent prior to transplantation and recurrent infection is a frequent cause of graft dysfunction. The significance of the recently described hepatitis G virus infection remains unproven. The aim of this study was to examine the role of hepatitis C virus and hepatitis G virus infection in chronic graft hepatitis after paediatric liver transplantation. METHODS: The prevalence of graft hepatitis and the role of hepatitis C virus and hepatitis G virus infections in 80 children after liver transplantation have been studied, with a median follow up of 4.4 years (range 0.4 to 10.7), and the persistence of hepatitis G infection in the presence of immunosuppression has been determined. RESULTS: Chronic graft hepatitis was diagnosed in 19/80 (24%) children and was most frequently seen in children transplanted for cryptogenic cirrhosis (71%). There was no significant difference in the prevalence of chronic hepatitis in those transplanted before or after donor anti-HCV screening. Hepatitis C infection occurred in three children transplanted prior to donor screening but in only one was associated with chronic hepatitis. Hepatitis G infection was found in 22/79 (28%) transplant recipients but was not associated with graft hepatitis. In 17/21 children hepatitis G infection persisted for a median of 5.2 years after transplantation. CONCLUSION: Chronic hepatitis occurred in 24% of children after liver transplantation, a similar prevalence to that in adults. Cryptogenic liver disease predisposed to graft hepatitis, but neither hepatitis C nor hepatitis G infection was associated. Hepatitis G virus caused a frequent and usually persistent infection after transplantation.  相似文献   

12.
AIMS: To investigate the transmission of hepatitis C virus from viraemic mothers to infants. METHODS: The study group comprised 54 hepatitis C ribonucleic acid (RNA) positive, human immunodeficiency virus (HIV) negative women attending antenatal clinic, their infants when born, 12 previous children and 44 children of 29 additional nonpregnant, viraemic women. During the study period there were 60 live births (1 set of twins, 5 sequential pregnancies). All infants were tested at birth for hepatitis C virus (HCV) RNA. Thirty infants were retested at 6 months or later. Breast milk from 30 mothers was tested for HCV RNA. The 56 other children were tested for antibody to HCV and HCV RNA. RESULTS: Of the 60 infants tested at birth, 30 failed to attend a 6 month or later followup, 2 infants were HCV viraemic by six months of age, 2 infants had one episode of possible HCV RNA positivity followed by loss of detectable HCV RNA and 26 have shown no evidence of HCV infection. Five of the 30 breast milk samples tested were positive for HCV RNA. Four older children of viraemic mothers were HCV RNA positive. CONCLUSIONS: In this study, 2 of 30 (6.6%) of infants born to HIV negative, HCV viraemic mothers acquired HCV infection. Breast milk remains a possible contributory source of infant HCV infection. Management of babies born to HCV viraemic mothers should include retesting of baby for HCV RNA at 3 to 6 months of age.  相似文献   

13.
OBJECTIVES: The hepatitis G virus (HGV) is a newly described flavivirus that affects a high proportion of patients with chronic viral hepatitis: our objective was to determine what role HGV might play in the course of disease. METHODS: We evaluated stored serum samples from 108 patients with chronic hepatitis B and 99 patients with chronic hepatitis C who participated in trials of alpha-interferon or ribavirin for the presence of hepatitis B virus (HBV) DNA and hepatitis C virus (HCV) RNA by branched DNA and for the presence of HGV RNA by polymerase chain reaction (PCR), using primers from the NS5 region of the genome. RESULTS: Initially, 20 (19%) patients with hepatitis B and 11 (11%) with hepatitis C had HGV RNA in their serum. Patients with and without HGV infection were similar with regard to clinical features, laboratory tests, and hepatic histology. HGV RNA levels fell during interferon therapy and became undetectable in those receiving the highest doses; however, HGV RNA levels returned to pretreatment values when therapy was stopped. With ribavirin therapy, HGV RNA levels did not change. Two- to 12-yr follow-up serum samples were available from 17 initially HGV RNA-positive patients, of whom only 10 (59%) were still positive. CONCLUSIONS: HGV infection is common among patients with chronic hepatitis B and C but has little effect on the short-term course of disease or response to therapy. HGV RNA levels are suppressed but not eradicated by alpha-interferon and are unaffected by ribavirin treatment. Spontaneous loss of HGV RNA occurs over time in a proportion of patients.  相似文献   

14.
The aim of the present investigation was to study two post-brushing water rinsing procedures: (1) on fluoride (F) accumulation in approximal dental plaque, and (2) on F clearance in the interdental area. Twenty subjects participated first in the accumulation study, including three experimental periods (A, B and C), each lasting for 7 days. During period A, they brushed with a 0.32% NaF dentifrice for 2 min, followed by a 1-min active mouth rinse with the toothpaste foam combined with 5 ml of water. During period B, the 2-min brushing was followed by three quick water rinses with 15 ml each. During period C, toothbrushing, which was carried out without any toothpaste, was followed by a 2-min active mouthrinse with 10 ml of a 0.05% NaF solution. All three procedures were performed in the morning (after breakfast) and in the evening (just before bedtime). The results showed that the accumulation of F in pooled approximal plaque after 7 days reached on average 2.7 times higher values after procedure A than B (p<0.001). Procedure C also resulted in more F in plaque than B (p<0.001). The same 20 subjects participated in the clearance study on a separate occasion. When measuring the F concentration in the interdental area at 3 h after the application, procedure A resulted in a significantly higher F concentration than both toothbrushing B and mouth rinse C; the AUC was 2.2 times larger for A than for B (p <0.001). Thus, both the accumulation of F in approximal plaque and the clearance of F in the interdental area are related to the mode of water rinsing after toothbrushing.  相似文献   

15.
Danish artificial insemination (AI) centres house several boars antibody positive to porcine reproductive and respiratory syndrome virus as well as PRRSV-naive boars which may become acutely infected. The risk of transmission of PRRSV by semen may therefore constitute a serious problem to the Danish pig industry. The use of a vaccination-program may be a way to avoid or reduce the problem. This study evaluates the use of two vaccines: One live, attenuated vaccine and one inactivated vaccine. A pronounced reduction in viremia and shedding of virus in semen was demonstrated by use of the live vaccine compared to the non-vaccinated control animals. In contrast, no changes in onset, level and duration of viremia and shedding of virus in semen were observed using the inactivated vaccine. Neither viremia nor seminal shedding of virus was detected in previously PRRSV-infected, PRRSV-antibody positive boars after challenge with a Danish field strain of PRRSV.  相似文献   

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18.
We present a case of hepatitis A infection in a 2.5-month-old male who became icteric after 18 d of birth. The diagnosis of hepatitis A was made by compatible clinical symptoms, laboratory results and liver biopsy showing evidence of hepatitis, and confirmed by detection of anti-HAV IgM antibodies. Because the mother had an acute icteric hepatitis A 1 week before delivery, and the viraemic phase of hepatitis A infection is very short, approximately 7 d, we suggest that the infant was infected by his mother, before birth.  相似文献   

19.
Cutaneous necrosis may occur as a complication of treatment with interferon. Here we report the first case of cutaneous necrosis developing in a patient receiving interferon alpha-2b for the treatment of chronic hepatitis C viral infection. The patient developed two necrotic lesions while receiving high doses of interferon. We suggest that discontinuation of treatment may be necessary to permit healing of such lesions. Although the exact mechanism involved in cutaneous necrosis remains unknown, our observations support earlier findings suggesting that intraarterial injection may be a factor.  相似文献   

20.
BACKGROUND: The hepatitis G virus (HGV) or GB virus C (GBV-C) is a new member of the Flaviviridae family. The virus is transmitted by transfusion of blood, infusion of some blood products, and by parenteral exposure to blood during intravenous drug use (IVDU) and haemodialysis. Transmission from mother to infant and by sexual contact has also been documented. Although the virus has been found in patients with acute and chronic hepatitis, evidence of disease association has not been forthcoming. The majority of patients carry the virus in the absence of liver enzyme abnormalities. OBJECTIVES: To review what is currently known about HGV/GBV-C in order to evaluate its similarity with other members of the Flaviviridae and the association of the virus with disease. RESULTS: The genomic organisation of the virus is typical for Flaviviridae, with long 5' and 3' untranslated regions (UTR). However, a clearly identifiable nucleocapsid encoding region is lacking. Polyprotein synthesis is mediated through an internal ribosome entry site (IRES) contained within the 5' UTR. Phylogenetic tree analysis of sequences derived from this region has demonstrated the existence of at least three genotypes. Apart from serum, HGV-RNA has been detected in lymphocytes also, but the quasispecies present in the two compartments appear to be different. The envelope glycoprotein E2 lacks a hypervariable region and is potentially the target of a neutralising antibody response. CONCLUSION: Molecular analysis of HGV reveals close similarity of the virus with HCV. However, an association of the virus with liver disease remains unresolved and no association of the virus with hepatocellular carcinoma has been reported.  相似文献   

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