The neurons and the synaptic endings in the primate basilar pontine gray.

Two types of neurons, projection and intrinsic, previously identified in Golgi preparations of the adult monkey (Macaca mulatta) basilar pontine gray (Cooper and Fox, '76) were observed electronmicroscopically in Macaca mulatta and the squirrel monkey Saimiri sciureus. The cell body of the projection neuron measures up to 37 micrometer and its cytoplasm is rich in organelles. The Goli apparatus, ribosomes, and mitochondria are disposed around the nucleus, while rough endoplasmic reticulum though abundant is usually confined to one half of the cell body. The cell body of the intrinsic neuron measures less than 20 micrometer and its cytoplasm displays prominent ribosomes, but a paucity of other organelles. Five types of synaptic profiles have been identified in the neuropil of the basilar pons; one measures up to 5 micrometer and the rest 2 micrometer or less. They are: (1) a large profile (MSV) containing medium size vesicles (500A) and a central core of mitochondria and neurofilaments; (2) a profile (SSV) containing small round vesicles (250-500 A) which is the most abundant and ubiquitous; (3) a profile (F) containing flattened or pleomorphic vesicles; (4) a profile (LSV) containing large oval egg shaped vesicles (750 A); and (5) a pale profile (PP) that contains oval and occasionally pleomorphic vesicles. MSV, SSV, and LSV terminals form asymmetrical contacts and F terminals form symmetrical contacts with both dendritic and vesicle-containing, pale profiles. The vesicle-containing, pale profile is both pre- and post-synaptic and participates in serial synapses. Following unilateral cortical ablations both dark and filamentous degeneration were observed in the ipsilateral basilar pontine gray.

HIV infection in autologous and allogeneic bone marrow transplant patients: a retrospective analysis of the Marseille bone marrow transplant population.

Twelve HIV-positive patients who either underwent or seroconverted after bone marrow transplantation (BMT) at the University of Marseille between 1981 and 1985 were reviewed in order to observe their rates of development of AIDS. Two patients were HIV positive prior to transplantation, while ten seroconverted after transplantation. Six patients underwent autologous BMT and six underwent allogeneic BMT; all of their respective donors were seronegative. Eleven patients developed AIDS (92%), with a mean AIDS-free time (AFT) of 1 year 8 months after BMT. Seven of those subjects died, with a mean survival over a 5-year follow-up period of 2.14 years after BMT. Five autologous recipients had a mean AFT of 2 years 3 months, with the sixth patient being AIDS free. The mean AFT for the allogeneic recipients was 1 year 2 months (p = NS), all of whom developed AIDS. These data suggest that the development of AIDS was rapid from the time when our patients seroconverted. However, this was not initially accompanied by poor survival. In summary, BMT may be indicated for HIV-positive patients who required myeloablation, despite an enhanced development of AIDS.

Cross-species graft-versus-host-disease is accompanied by a donor-derived cellular immune response.

Acute graft-versus-host-disease is classically described as reactivity of donor lymphocytes to recipient alloantigens. To date there is debate as to whether GVHD can be induced across a species barrier. We recently reported the induction of stable xenogeneic chimerism (rat-->mouse) and donor-specific transplantation tolerance using the transplantation of untreated rat bone marrow cells into B10 mouse recipients. Survival of chimeras was excellent, and there was no evidence of GVHD. We now describe the induction of xenogeneic GVHD by transplanting large numbers of donor rat spleen cells with the bone marrow inoculum. All chimeras that received bone marrow and untreated spleen cells developed an external appearance compatible with GVHD and had a median survival time of 14 days. Mice that received equivalent numbers of untreated rat bone marrow alone appeared healthy, had no evidence for GVHD, and survived > 90 days. The usual epithelial target tissues for allogeneic GVHD in those mice that received xenogeneic bone marrow and spleen cells showed the presence of tissue injury and histologic features compatible with GVHD. Donor rat MHC class I and class II positive cells were prominent cell types present in the tongues of mice that developed features of GVHD, and this was accompanied by a significant inflammatory tissue response with loss of the dermal-epidermal architecture. In contrast, fully xenogeneic chimeras without GVHD had no evidence for tissue injury or pathologic cellular infiltrates when examined by immunohistochemical analysis. These data suggest that although fully xenogeneic chimeras resist GVHD, GVHD can be induced across a species barrier if sufficient numbers of donor rat spleen cells are added to the bone marrow inoculum. Further comparisons of these models may provide an approach to study the mechanisms responsible for xenoreactivity in vivo.

Rapamycin but not FK506 inhibits the proliferation of mononuclear phagocytes induced by colony-stimulating factors.

FK506, CsA, and rapamycin are potent inhibitors of T lymphocyte activation; relatively little is known of their effects on cells of the monocyte/macrophage lineage. Studies were undertaken to determine the effects of these drugs on the proliferative response of bone marrow-derived mononuclear phagocytes (BMMP) to CSFs. Rapamycin inhibited the proliferation of BMMP cultured in the presence of 10% L cell-conditioned medium, used as a source of macrophage CSF. The inhibition by rapamycin was dose dependent and apparent at concentrations of 0.1 nM or greater. In a similar fashion, rapamycin inhibited the proliferation of BMMP stimulated by the recombinant forms of murine IL-3 and murine granulocyte-macrophage CSF, and human macrophage CSF. In contrast, neither FK506 nor CsA at concentrations as high as 1000 nM diminished the proliferation of BMMP cultured under identical conditions. FK506, but not CsA, blocked the inhibitory effects of rapamycin on the response of BMMP to CSFs. In summary, these data indicate that rapamycin inhibits the proliferation of BMMP in response to CSFs. These results imply that patients receiving rapamycin, but not FK506 or CsA, may have an impaired ability to generate a functional mononuclear phagocyte population.

Transplantation in HIV+ patients.

Twenty-five whole-organ recipients treated from 1981 through September 1988 were HIV carriers. Eleven were infected before transplantation, although this was not known until later in 8 recipients. The other 14 were infected perioperatively. Ten of the 25 recipients were infants or children. The organs transplanted were the liver (n = 15), and the heart or kidney (n = 5, each). After a mean follow-up of 2.75 years (range, 0.7-6.6 years), 13 recipients are alive. Survival is 7/15, 2/5, and 4/5 of the liver, heart, and kidney recipients, respectively. The best results were in the pediatric group (70% survival) in which only 1 of 10 patients died of AIDS. In contrast, AIDS caused the death of 5 of 15 adult recipients and was the leading cause of death. Transplantation plus immunosuppression appeared to shorten the AIDS-free time in HIV+ patients as compared to nontransplant hemophiliac and transfusion control groups. Accrual of HIV+ transplant recipients has slowed markedly since the systematic screening of donors, recipients, and blood products was begun in 1985.

Short-term myeloid reconstitution following TBI is not adversely affected by doses of FK506 that abrogate lethal GVHD.

Studies were undertaken to determine whether the doses of FK506 that are effective for acute GVHD prophylaxis following lethal irradiation and bone marrow transplantation (BMT) would also suppress myeloid cell reconstitution. FK506 (3 mg/kg/day) abrogated acute lethal graft versus host disease (GVHD) in lethally irradiated C57BL/10SnJ (H-2b) recipient mice given histoincompatible BM plus spleen cells from B10.BR (H-2k) donors and this dose was used in all of the studies. Endogenous and exogenous myeloid repopulation was studied in mice given daily injections of either FK506, an equivalent amount of carrier solvent or no treatment throughout the interval between total body irradiation (TBI) and the day of assay. Repopulation was studied after 400 or 500 cGy TBI (endogenous) and after 950 cGy TBI plus injection with syngeneic BM (exogenous). No consistent adverse effects of FK506 were seen during either exogenous or endogenous recovery. Parameters studied included hematocrit (Hct), WBC count, cells per humerus, spleen weight, splenic colony-forming units, % spleen or BM 59Fe uptake and colony forming cells per humerus. Similarly, when lethally irradiated secondary recipients were reconstituted with BM from FK506 treated primary recipients (lethal irradiation plus exogenous BM), no consistent effects were observed. These data suggest that FK506 given to prevent GVHD would not compromise the myeloid recovery that is critical for survival in the interval of time following shortly after BMT.

The hypoglossal nucleus of the primate: a Golgi study.

The neurons of the hypoglossal nucleus were examined in Golgi preparations of adult macaque and squirrel monkeys. Two distinct types of neurons were found. The first type was a large multipolar cell which was typical of the majority of the neurons of the nucleus. Its soma ranged in size from 18 to 50 micrometers and numerous dendrites emerged from it. The dendritic spread of these neurons was within the ipsilateral nucleus, across the midline into the contralateral hypoglossal nucleus, or out into the adjacent reticular formation. The second type of neuron was a small cell. The soma of this neuron was oval in shape, measured less than 20 micrometers in its largest diameter, and gave off only two or three dendrites which remained within the nucleus.

Increases in fluoride, calcium, and phosphate in dental plaque resulting from the use of a mineralizing mouthrinse containing urea and monofluorophosphate.

A mouthrinse used ten times over a four-day period increased the concentration of acid-extractable fluoride in immature plaque by 320%, calcium by 190%, and phosphate by 97%. Corresponding increases in mature plaque were smaller, yet significant. Diffusion of the ions from plaque was restricted, and hence a prolonged caries-inhibitory effect can be expected.

Immediate and delayed effects of an enzyme-dependent mineralizing mouthrinse on dental plaque.

Twenty-two children aged 13 to 14 years rinsed for 3 X 1 min periods with a supersaturated calcium phosphate solution containing urea and monofluorophosphate. Plaque sampled one min after the last rinse showed a marked increase in water-extractable F and a smaller increase in Ca but no increase in water-extractable P. Water-insoluble forms of all three ions were elevated, however. The mean plaque pH was 8.28. Plaque sampled 24 hr after the last rinse showed significant increases in water-insoluble F and Ca only, and no increase in pH. The prompt pH rise and disappearance of water-soluble P suggest that, on exposure to the mineralizing solution, urea and monofluorophosphate are rapidly hydrolyzed by plaque enzymes to provide catabolites which cause the immediate precipitation of fluoridated calcium phosphate.

Stylohamular dissection: a new method for en bloc reaction of malignancies of the infratemporal fossa.

This study is a description of the "stylohamular" dissection, a technique for the en bloc resection of the infratemporal fossa. The medial plane of this dissection extends from the styloid process to the hamulus of the pterygoid just lateral to the foramen lacerum, allowing the surgeon to spare the internal carotid artery. The foramen ovale and foramen spinosum are routinely exposed during this procedure. Medially, the pterygoid musculature serves as the margin of the cancer block. Posteriorly, the mastoid tip may be included in this resection. Anteriorly, the lateral pterygoid plate is resected making it the anterior vertical plane of the dissection. Laterally, skin and mandible are the block margins. In the last three years, this approach has been utilized in eight patients with advance malignancies involving the infratemporal fossa. The results are encouraging. Five patients have remained well and free of disease for a maximum of three years postoperatively. Two patients have had recurrence of their tumor from six months to one year postoperatively. Palliation in all patients was excellent. The literature on various infratemporal dissections and their results is reviewed.

Sphenoethmoidectomy: the case for ethmoid marsupialization.

The authors report 510 sphenoethmoidectomies performed on 255 patients between 1969 and 1985. An overall polyp recurrence rate of 19.2% and less than a 1% complication rate are reported during that time. In patients followed jointly by the otolaryngologists and allergist, including 374 consecutive sphenoethmoidectomies on 187 patients who had this operation performed by the senior author, there was an overall polyp recurrence rate of 15% and a complication rate which was again less than 1%. Recent improvements in recurrence rates and diminished complication rates are attributed to better visualization and adherence to the concept of complete exenteration or marsupialization of the ethmoid labyrinth including middle turbinate resection in every case. Cooperation between the otolaryngologist and allergist is stressed, along with the realization that pulmonary and sinus diseases are frequently interrelated and may both be benefited by the performance of sphenoethmoidectomy in the patient with hyperplastic rhinosinusitis.

Clinical and histologic response of subcutaneous expanded polytetrafluoroethylene (Gore-Tex) and porous high-density polyethylene (Medpor) implants to acute and early infection.

OBJECTIVE: To examine the responses of subcutaneously implanted expanded polytetrafluoroethylene (e-PTFE, Gore-Tex) and porous high-density polyethylene (PHDPE, Medpor) to experimentally induced infection. DESIGN: Sprague-Dawley rats were implanted subcutaneously with either e-PTFE or PHDPE implants. Inocula of Staphylococcus aureus were injected directly over the implants and the wounds were observed for clinical signs of infection. After the animals were killed, the implants were harvested and underwent Histologic examination. SUBJECTS: Twenty-eight adult male Sprague-Dawley rats weighing 200 to 250 g. INTERVENTION: A 8-mm diameter, 1-mm-thick implant of either e-PTFE or PHDPE was placed in a subcutaneous pocket over each animal's dorsum. Either at the time of implantation or 14 days afterward, an inoculum of 10(9) colony-forming units of S aureus was injected transcutaneously directly over each implant. The animals were observed for 7 days before being killed. The implants were harvested and examined by both conventional light and scanning electron microscopy, and the degree of capsule reaction, infection, inflammation, and implant degradation was evaluated. RESULTS: Implants inoculated at the time of implantation were more likely to become clinically infected. Results for e-PTFE and PHDPE implants were similar in this group (5 of 5 e-PTFE and 5 of 5 PHDPE implants infected). The PHDPE implants inoculated 14 days after implantation were less likely to become infected (1 of 4 infected) than e-PTFE implants (3 of 4 infected), and were statistically less likely to become infected than PHDPE implants inoculated immediately after implantation (25% vs 100%; P < .02). Histologically, this resistance to infection correlated with increasing fibrovascular ingrowth into the PHDPE implants. The infected PHDPE implant had little to no ingrowth compared with PHDPE control implants. The uninfected e-PTFE implant had evidence of early fibrovascular ingrowth into the peripheral pores of the implant. CONCLUSIONS: Because of differences in pore size, PHDPE promotes faster fibrovascular ingrowth. The presence of vascularized host tissue in and around the implant lends stability and resistance to experimentally induced infection. Conservative management of clinical implant infections should be considered if bacterial seeding occurs after substantial fibrovascular ingrowth is present. Future alloplast designs should include pore sizes that will encourage invasion of the implant by host tissue.

Comparison of subperiosteal vs subgaleal elevation techniques used in forehead lifts.

OBJECTIVES: To compare eyebrow and forehead elevation and tension among the following 3 surgical techniques: subperiosteal dissection to the supraorbital rim, subperiosteal dissection with release (elevation, incision, and spread) of periosteum at the supraorbital rim, and subgaleal dissection to the supraorbital rim, and to determine the optimal method of elevation in an aesthetically accepted range for the endoscopic forehead lift. DESIGN: A randomized, self-controlled study using an open approach to the forehead in cadaver heads. Each half of head was compared with the other in the following 2 study groups: subperiosteal dissection without release vs subperiosteal dissection with release of periosteum (group 1) and subperiosteal dissection with release of periosteum vs subgaleal dissection. SETTING: Anatomy laboratory at a university medical center. SUBJECTS: Eight cadaver heads fixed with ethylene glycol in each group. INTERVENTION: Predissection distances in millimeters from fixed anatomic landmarks were measured. The forehead flaps were elevated using a coronal incision and divided with a midline incision for side-to-side comparison. Cadaver heads and side of surgical intervention were selected randomly. The flap tensions associated with incremental flap advancement of 0.5 and 1.0 cm were measured. Traction of 2.2 kg was then applied to each flap, and distances between the fixed landmarks were measured. MAIN OUTCOME MEASURES: Mean predissection and postdissection distance of brow and forehead elevation for each dissection type and mean distance and median tension of brow and forehead elevation within each group. RESULTS: The mean postdissection brow measurements at rest were significantly greater than the mean predissection measurements at most landmarks in all dissections for both groups (P<.05). The mean postdissection brow and forehead measurements with 2.2 kg of traction were significantly greater than the mean predissection measurements at all landmarks in all dissections for both groups (P<.05). The mean increase in distance from predissection to postdissection (at rest and with 2.2 kg of traction) did not significantly differ between the different dissection types (P>.05). For group 1, the median flap tension for subperiosteal dissection without release was greater than that for subperiosteal dissection with release (P>.05). For group 2, subperiosteal dissection with release had greater median flap tension than subgaleal dissection (P>.05). CONCLUSIONS: All 3 methods of dissection significantly elevated the brow at rest for most landmarks. All 3 methods of dissection significantly elevated the brow and forehead when traction was applied to the flap. Brow and forehead elevation at rest and with 2.2 kg of traction did not significantly differ between the dissections. Subgaleal dissection was associated with less flap tension compared with the subperiosteal dissection with or without release. The data support the use of all 3 methods of forehead dissection for brow elevation and subgaleal forehead dissection as the optimal approach for the forehead lift, whether performed endoscopically or open.

Comparison of the Bligh and Dyer and Folch methods for total lipid determination in a broad range of marine tissue.

For many studies, it is important to measure the total lipid content of biological samples accurately. The Bligh and Dyer method of extraction was developed as a rapid but effective method for determining total lipid content in fish muscle. However, it is also widely used in studies measuring total lipid content of whole fish and other tissues. Although some investigators may have used modified Bligh and Dyer procedures, rarely have modifications been specified nor has their effectiveness been quantitatively evaluated. Thus, we compared this method with that of the classic Folch extraction in determining total lipid content of fish samples ranging from 0.5 to 26.6% lipid. We performed both methods as originally specified, i.e., using the chloroform/methanol/water ratios of 1:2:0.8 and 2:2:1.8 (before and after dilution, respectively) for Bligh and Dyer and of 8:4:3 for Folch, and with the initial solvent/sample ratios of (3+1):1 (Bligh and Dyer) and 20:1 (Folch). We also compared these with several other solvent/sample ratios. In samples containing <2% lipid, the results of the two methods did not differ. However, for samples containing >2% lipid, the Bligh and Dyer method produced significantly lower estimates of lipid content, and this underestimation increased significantly with increasing lipid content of the sample. In the highest lipid samples, lipid content was underestimated by up to 50% using the Bligh and Dyer method. However, we found a highly significant linear relationship between the two methods, which will permit the correction of reported lipid levels in samples previously analyzed using an unmodified Bligh and Dyer extraction. In the future, modifications to procedures and solvent/sample ratios should be described.

Neurons of the hypoglossal nucleus of the rat.

The neurons of the hypoglossal nucleus in the medulla of the brain stem of the laboratory rat are described from Nissl, Golgi impregnation, horseradish peroxidase, and electron microscopic preparations. The cell body of the neuron is multipolar, measures 30 micrometers to 40 micrometers its largest diameter, and gives off four to five primary dendrites. As the dendrites radiate from the cell body they may remain within the ipsilateral hypoglossal nucleus, cross the midline into the contralateral hypoglossal nucleus, or extend out into the adjacent reticular formation.

Infratemporal fossa and lateral skull base dissection: long-term results.

In 1981, we described a new surgical technique featuring en bloc removal of infratemporal fossa malignancies. This approach offered a systematic resection of cancers in this region and was designated "stylohamular dissection" because the medial boundary of the bloc is surgical plane between the styloid process and the hamulus of the pterygoid. All structures lateral to this plane are removed, sparing the internal carotid artery. Since 1977, twenty infratemporal fossa and lateral skull base dissections have been performed for palliation of metastatic or recurrent disease in the infratemporal fossa. Most patients obtained palliation of trismus, facial pain, or relief from an unmanageable ulcerating lesion. This technique offers improved average disease-free intervals, as well as enhanced survival rates compared to non-en bloc resections. A summary of the case presentations, survival statistics, and surgical technique with detailed cadaver dissections are presented.

Caries progression in primary molars: 24-month results from a minimal treatment programme.

A 2-stage topical treatment regimen (AgF followed by SnF2) was used in an attempt to limit caries progression in the primary molars of children participating in a minimal treatment programme. The children lived in an isolated community in western New South Wales (fluoride in water less than 0.2 parts/10(6)) and were from a low socioeconomic background. The progression, over a 24-month period, of 281 established lesions in the approximal and occlusal surfaces of primary molars in 54 subjects (mean age 7.0 years) was determined from bitewing radiographs. Of the lesions studied, the majority (69%) were in dentine at baseline. At 24 months, 74% of the approximal surface lesions and 90% of the occlusal surface lesions that were in enamel at baseline remained unchanged. The greatest change occurred in the approximal surface lesions that were within 1 mm of the pulp at baseline. Only 35% of the lesions required any treatment other than topical metal fluoride therapy during the 24-month period.

Caries experience and sex related tea consumption amongst 13-14-year-old children in Palmyra, Syrian Arab Republic.

Associations were examined between caries experience and the volume of tea consumed/day by schoolchildren in Palmyra, Syria. Girls had significantly high DMFT scores and consumed less tea than boys.

Oral health of Australian children using surface and artesian water supplies.

Oral health parameters were compared for 6--8 and 10--11-year-old children living in neighbouring. N. S. W. towns, where the community water supplies consisted of artesian and river were respectively. The demographic characteristics, living pattern and dietary carbohydrate challenge were similar in the two areas and effective oral hygiene practices were uniformly lacking. Children in the artesian water area had 40% lower caries prevalence (DIMFT), 50% less severe carious lesions (SR) and significantly better oral hygiene (OHI) and gingival condition (PI) and correspondingly lesser treatment needs than those supplied by river water. The findings were examined in relation to the concentrations of 10 elements in roof catchment, river and artesian water. Apart from a contribution by fluoride to better oral health, the results implicate lithium as a possible beneficial element.

Oral conditions in Australian children of Aboriginal and Caucasian descent.

Oral health parameters were examined for 211 schoolchildren (128 Aborigines and 83 Caucasians) representative of the 6--8 and 10--11 year age groups in the Brewarrina and Walgett areas of western New South Wales (fluoride in water less than or equal to 0.02-0.26 parts/10(6)). Despite similar dietary carbohydrate challenge and tooth eruption patterns, Aboriginal children, most of whom were members of a transitional community within a low socioeconomic stratum, had higher prevalence of caries (DIMFT) and severity rating of carious lesions (SR), poorer oral hygiene (OHI) and more gingivitis (PI) than Caucasian children, in both age groups. Tooth defects were more frequent (2.5 times) and severe in Aborigines than in Caucasians. Outstanding treatment needs were very high in both ethnic groups, but more so in Aborigines.