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R C Sanders

Publications and source records attributed to R C Sanders.

At least 19 recordsLinked to original sources
PubMed1995

Criteria for the prenatal diagnosis of classic bladder exstrophy.

OBJECTIVE: To define ultrasonographic criteria for the prenatal diagnosis of classic bladder exstrophy. METHODS: Forty-three prenatal ultrasound scans were studied from 25 pregnancies in which live delivery of an infant with classic bladder exstrophy occurred. The diagnosis of bladder exstrophy could be made retrospectively in 29 prenatal studies from 17 pregnancies. The time of the fetal ultrasound varied from 14-36 weeks' gestation (mean 23). The diagnosis of bladder exstrophy was made before delivery in only three cases. RESULTS: Five factors associated with bladder exstrophy were identified: 1) The bladder was not visualized on ultrasound in 12 of 17 cases (71%); 2) a lower abdominal bulge representing the exstrophied bladder was seen in eight of 17 cases (47%); 3) a small penis with anteriorly displaced scrotum was identified in eight of 14 males (57%); 4) the umbilical insertion was low set in five of 17 cases (29%); and 5) abnormal widening of the iliac crests was seen in three of 17 cases (18%). CONCLUSION: The prenatal diagnosis of bladder exstrophy should be considered any time the bladder is not visualized or any of the aforementioned factors are noted.

Bladder Exstrophy↗
PubMed1994

Immunoglobulin G antibody responses to polyvalent pneumococcal vaccine in children in the highlands of Papua New Guinea.

The immunoglobulin G (IgG) antibody responses to a pneumococcal polysaccharide vaccine were examined for 480 children aged 3 months to 5 years and living in Tari, Southern Highlands Province, Papua New Guinea. Antipneumococcal IgG to the seven serotypes most frequently causing invasive disease (types 2, 5, 6B, 7F, 14, 19F, and 23F) was measured by an enzyme-linked immunosorbent assay in serum collected before vaccination and 1 and 6 months after vaccination. Prevaccination antibody levels fell rapidly after 3 months of age and remained low throughout the first 2 years of life. One month after vaccination, geometric mean titers of antipneumococcal IgG to serotypes 2, 7F, 23F, and 5 were at least twice those of antibodies in nonvaccinated children of the same age from the ages of 5, 6, 9, and 12 months onwards, respectively; postvaccination antibody responses to serotypes 6B, 14, and 19F rose gradually during the second year of life. Elevated antibody titers to serotypes 2 and 7F were maintained 6 months after vaccination. Thus, young Papua New Guinean children are capable of mounting a good immune response to some pneumococcal capsular polysaccharides from a young age, and the antibody responses to capsular polysaccharides are consistent with studies in developed countries. However, in Papua New Guinea, the serogroup distribution of invasive disease matches the immunogenic components of the pneumococcal polysaccharide vaccine more closely than in developed countries, a fact which helps to explain the results of controlled trials in Papua New Guinea, in which this vaccine prevented death and severe morbidity from pneumonia in young children.

Age Factors↗
PubMed1994

Osteogenesis imperfecta and campomelic dysplasia: difficulties in prenatal diagnosis.

The classic features of osteogenesis imperfecta and campomelic dysplasia typically are so specific that these two forms of skeletal dysplasia are among the few that can be diagnosed in the second trimester of pregnancy. We report a series of seven examples of osteogenesis imperfecta and one example of campomelic dwarfism to illustrate the difficulty of differentiating these two disorders in utero. The prenatal sonographic findings in three of the osteogenesis imperfecta cases mimicked campomelic dwarfism, whereas the case of campomelic dwarfism was antenatally diagnosed as osteogenesis imperfecta.

Adolescent↗
PubMed1994

Arbovirus disease in Papua New Guinea.

It is clear that exposure to arthropod-borne viruses is common in the populations of both Papua New Guinea and Irian Jaya. Clinical disease resulting from these infections has been reported although the paucity of case reports and combined clinical experience suggest that it is rare. Dengue epidemics due to dengue-1 and dengue-2 have occurred and it is likely that dengue-3 is also present in the region. No cases of dengue haemorrhagic fever have been described. Murray Valley encephalitis, Ross River and antigenically related viruses are widespread in Papua New Guinea and Irian Jaya, particularly in the lowland and coastal areas. Antibodies to Japanese encephalitis virus have not been found in blood samples from Papua New Guinea or Irian Jaya. As Papua New Guinea is developed, new areas of the country are opened up and ecosystems are altered. It is important that physicians based in Papua New Guinea, and those who deal with patients living or working here, are aware of the arbovirus diseases which occur and the potential and preventable problems posed by them to both the individual and the community.

Alphavirus Infections↗
PubMed1993

The role of ultrasound in prostate cancer detection in patients with an elevated prostate specific antigen level but no prostatic nodule.

An increased level of prostate specific antigen (PSA) in the blood is a relatively sensitive indicator of prostate disease; a significant minority of men with increased PSA will have prostate carcinoma. A total of 736 men with a PSA elevation of greater than 4.2 without a rectally palpable prostate mass were evaluated with transrectal ultrasound at the Ultrasound Institute of Baltimore over a three-year period. Transrectal biopsy under ultrasound control was performed when a localized mass was seen on ultrasound or the prostate was small and the PSA level significantly elevated (93% of the series underwent biopsy). There was a positive biopsy yield for cancer of 38.5% in the cases biopsied. This high positive yield was achieved by combining high quality ultrasound with two to three samples from a visible mass and random samples from other sites.

Adult↗
PubMed1993

Ultrasonic clues to the detection of chromosomal anomalies.

The ultrasonic detection of fetal anomalies may well be the most challenging aspect of diagnostic ultrasound and, because ultrasonic clues to a chromosomal anomaly may be subtle, much depends on high quality ultrasound. Although difficult, the field is exciting and rewarding. It is hoped that recognition of the various common manifestations of chromosomal anomalies described in this article will increase the number of chromosomal anomalies detected and ameliorate the consequences of these disorders.

Chromosome Aberrations↗
PubMed1992

In utero sonography of genitourinary anomalies.

Congenital anomalies of the genitourinary system represent the commonest fetal anomaly. The sonographic findings in hydronephrosis, multicystic kidney (dysplastic kidney), polycystic kidney, and renal agenesis are reviewed.

Adult↗
PubMed1992

Subacute sclerosing panencephalitis (SSPE) in Papua New Guinea: a high incidence in young children.

Eighty-seven cases of subacute sclerosing panencephalitis (SSPE) were diagnosed from September 1988 to April 1991 in Papua New Guinea (PNG), by demonstration of high-titre measles-specific antibodies in cerebrospinal fluid (CSF). For 1990 the annual incidence of SSPE, for the study provinces, was calculated to be 56 cases per million under 20 years of age and it is expected that this figure will be higher in 1991. The mean age of presentation was 4.9 years, with a male to female ratio of 1.8:1. An elevation in the ratio of immunoglobulin G as a percentage of total protein in CSF and an increase in the CSF:serum immunoglobulin G ratio was shown in SSPE patients. The dramatic appearance and high frequency of the disease in PNG might relate to the early age of measles infection encountered in children in this country.

Child↗
PubMed1992

Failure to isolate human T cell lymphotropic virus type I and to detect variant-specific genomic sequences by polymerase chain reaction in Melanesians with indeterminate western immunoblot.

The controversy over the endemicity of human T cell lymphotropic virus type I (HTLV-I) in Melanesia has been settled recently by the isolation of genetically distinct, highly divergent sequence variants of HTLV-I from unrelated inhabitants of Papua New Guinea and the Solomon Islands. Still at issue, however, is the significance of the high frequency of indeterminate HTLV-I Western blots (defined as reactivity to only gag-encoded proteins) among Melanesians. To investigate whether this indeterminate seroreactivity reflects specific reactivity to the Melanesian HTLV-I variants, 27 seroindeterminate Melanesians from Papua New Guinea and the Solomon Islands were studied for evidence of HTLV-I infection. Although antibodies against Melanesian variant-specific env gene products and variant-specific env gene sequences were detected by Western blot analysis and polymerase chain reaction, respectively, in all 11 HTLV-I Western blot-positive Melanesians, none of the 27 seroindeterminate Melanesians had such variant-specific antibodies or HTLV-I proviral sequences. In addition, attempts to isolate HTLV-I from seroindeterminate individuals were unsuccessful. These data indicate that HTLV-I infection is not the cause of the indeterminate Western blot reactivity seen in Melanesia.

Adolescent↗
PubMed1992

Markers of hepatitis B infection in Tari District, Southern Highlands Province, Papua New Guinea.

Serum samples collected from two groups in the Tari District of Southern Highlands Province were assayed for markers of hepatitis B virus (HBV) infection. 85% of women of childbearing age were found to have markers of HBV infection; 37% were positive for HBV surface antigen (HBsAg), indicative of the chronic carrier state, and 6.6% were positive for HBV e antigen (HBeAg), indicating the presence of actively replicating virus. 75% of women negative for HBsAg were positive for antibody to HBV core antigen (HBcAb), a marker of past infection. A group of children aged 6 to 18 years showed a significantly lower prevalence of markers of infection (66%) but higher rates of HBsAg positivity (46%) and HBeAg positivity (30%). Only 37% of the HBsAg-negative children in this group were positive for HBcAb. The results from this serosurvey suggest that the major route of HBV transmission in this population is horizontal, between older children, though significant transmission also occurs during the neonatal period.

Acute Disease↗
PubMed1991

Characterization of a variant of human T-lymphotropic virus type I isolated from a healthy member of a remote, recently contacted group in Papua New Guinea.

We report the characterization of a variant of human T-lymphotropic virus type I (HTLV-I) isolated from an interleukin 2-dependent, CD8+ T-cell line derived from peripheral blood mononuclear cells of a healthy member of a remote, recently contacted hunter-horticulturalist group (Hagahai) in Madang province of Papua New Guinea. Antigenic characterization of this variant, designated PNG-1, by immunofluorescence, indicated no expression of gag-encoded proteins p19 and p24 (even after incubation with 5-bromo-2'-deoxyuridine), using monoclonal and polyclonal antibodies against HTLV-I gag gene products. Virus-specific proteins of 15, 19, 46, 53, and 61/68 kDa were demonstrated by Western blot analysis, using sera from patients with serologically and/or virologically confirmed HTLV-I myeloneuropathy, sera from HTLV-I-infected rabbits, and antibodies prepared against the C terminus of the major envelope glycoprotein gp46. Restriction endonuclease maps of PNG-1 proviral DNA differed from that of a prototype strain of HTLV-I (MT-2), but, as verified by polymerase chain reaction, PNG-1 was definitely HTLV-I, not HTLV-II. Nucleotide sequencing and further molecular genetic studies of this variant may provide insights into the origin and evolution of HTLV-I.

Cells, Cultured↗
PubMed1991

Infertility diagnosis by ultrasound.

Ultrasound is of value in the investigation and management of infertility in males and females. Monitoring of follicle growth and follicle aspiration is well accepted and commonly used. Defects of ovulation such as polycystic ovary disease or luteinized unruptured follicle syndrome may be recognized. Problems related to the union of the sperm and ova may also be seen. Obstructing lesions such as endometriosis and fibroids may be investigated by ultrasound. In males the principle use of ultrasound lies in the examination of the seminal vesicles, vas deferens, and ejaculatory ducts to see whether they are intact and unobstructed. Defective sperm motility may be due to varicoceles which are easily detected by the use of ultrasound.

Female↗
PubMed1991

Rotavirus excretion by village pigs in Papua New Guinea.

Cohort studies were conducted on 29 pigs from 3 villages in the Highlands of Papua New Guinea. Animals ranged in age from 9 d to 5 m old. Three hundred and twenty nine faecal samples were collected from individual pigs followed over 3 to 6 w periods, and were examined for group A rotavirus antigen by ELISA, and rotaviral genomic RNA by polyacrylamide gel electrophoresis (PAGE). Electron microscopy was also conducted on selected samples. Group A rotavirus was detected in the faeces of 16 pigs with infected individuals coming from all villages. Non-group A rotavirus resembling group C was found in faeces from pigs from 2 villages. All of the group A rotaviruses examined had the same electrophoretype and this was distinct from that of the common type infecting humans in the area at the time of the study. None of the group A positive samples reacted with monoclonal antisera specific for human group A rotaviruses of serotypes 1, 2, 3, 4, or 8. The non-group A rotaviruses also all had identical electrophoretypes. In contrast to previous findings in intensive piggeries, rotavirus infection did not occur in all young pigs and was not limited to young animals under 2 m of age. Infected pigs varied in age from 12 days to 20 weeks of age. This pattern of infection was attributed to the non-intensive husbandry situations in the villages, with less opportunity for transmission to occur than in intensive piggeries.

Animal Husbandry↗
PubMed1991

Obstructed uterovaginal anomalies: demonstration with sonography. Part I. Neonates and infants.

The sonograms of five neonates with an obstructed urogenital sinus and four with an obstructed cloaca were retrospectively reviewed to determine the sonographic features and the role of pre- and postnatal sonography in the diagnosis and management of hydrocolpos. On pre- and/or postnatal sonograms, the obstructed genital tract was visualized in seven neonates as a large cystic pelvic-abdominal mass, which was the markedly distended urine-filled vagina. One neonate had multiple cystic masses, which resulted from an obstructed duplex genital tract. In one of the neonates with an obstructed cloaca, the anomaly was not diagnosed. The bladder was compressed by the distended vagina and was not visualized in five patients. A vaginal fluid-debris level in six patients was a key finding that distinguished the vagina from the bladder. Obstruction of the urinary tract was an associated feature. An obstructed uterovaginal anomaly with renal dysplasia and oligohydramnios on prenatal sonograms indicates a poor prognosis. Sonography contributes to the diagnosis of an obstructed genital tract and helps define the internal genital anatomy.

Cloaca↗
PubMed1991

Obstructed uterovaginal anomalies: demonstration with sonography. Part II. Teenagers.

The sonograms of 13 patients with obstructed uterovaginal anomalies were reviewed to determine the role of sonography in diagnosis and management. In a retrospective analysis, the authors were able to define the cause of the obstruction and the upper level and length of the obstruction by combining the sonographic findings with those from the physical examination (ie, bulging hymen, blind vaginal pouch, no vaginal depth, normal vagina) or by combining transabdominal sonography with simultaneous digital insertion into the vaginal orifice. When the sonogram demonstrated hematometrocolpos or hematocolpos, the lesion was due to an imperforate hymen (n = 1) or high, middle, or low transverse vaginal septum (n = 7). When the sonogram demonstrated a hematometra, the lesion was due to Mayer-Rokitansky-Küster-Hauser syndrome with functioning uterine anlage(n) (n = 2), cervical dysgenesis (n = 1), and an obstructed uterine horn (n = 2). The presence and patency or absence of the cervix was established. Since the differentiation between a transverse vaginal septum, Mayer-Rokitansky-Küster-Hauser syndrome with active anlagen, and cervical dysgenesis with absent vagina cannot be made clinically, sonography provides important presurgical information.

Adolescent↗
PubMed1991

Prenatal diagnosis of structural abnormalities.

In the past year, improved ultrasonographic quality has allowed the imaging of more and more subtle anomalies. A major focus of recent discussion, ie, whether the combination of ultrasonographic and maternal blood test results (eg, serum alpha-fetoprotein level) is a satisfactory screening method for commonplace anomalies such as Down's syndrome or spina bifida, is reviewed. Whether these noninvasive tests need to be supplemented by amniocentesis is also discussed, as are ultrasonographic markers for various trisomy syndromes and the association between renal abnormalities and chromosomal defects.

Chromosome Aberrations↗
PubMed1991

Immunogenicity of standard dose Edmonston-Zagreb measles vaccine in highland Papua New Guinean children from four months of age.

A small-scale trial was carried out at Tari in the Southern Highlands Province of Papua New Guinea to determine the effectiveness of a standard subcutaneous dose of Edmonston-Zagreb measles vaccine (Institute of Immunology, Zagreb) administered to children at less than 8 months of age. Specific antibody levels were measured before and 7-11 weeks after vaccination using an ELISA system. Paired sera from 41 children vaccinated at 4-7 months of age and from 18 children vaccinated routinely at 8-29 months of age were available for comparison. No child 6 months of age or older had detectable maternal antibodies and all of these seroconverted. Post-vaccination titres in 12 children aged 6-7 months were not significantly different from those in older children and 1 year later, post-vaccination titres were still high. In Papua New Guinea, and perhaps in other developing countries, it may prove appropriate and acceptable to vaccinate with Edmonston-Zagreb measles vaccine at 6 months of age without recourse to augmentation of dose from that currently recommended in older children.

Antibodies, Viral↗