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PubMed1984

The Meckel cave: computed tomographic study. Part I: Normal anatomy; Part II: Pathology.

A formalin-fixed cadaver head with air filling the cisternal and ventricular spaces was scanned by high-resolution computed tomography (CT) in multiple planes (axial, coronal, and sagittal) through the Meckel cave. Correlation of the CT appearance of the Meckel cave was made with an anatomic dissection and whole-head band saw cross-sections. The appearance of the Meckel caves in normal patients was defined using similar high-resolution CT technique with intravenous and intrathecal contrast enhancement. CT techniques allowed consistent and accurate definition of the Meckel cave, the fifth cranial nerve, and adjacent anatomic structures. CT findings of 13 patients with lesions of the Meckel cave are also reviewed, including six trigeminal schwannomas, three meningiomas, two secondary tumors, one glioma, and one congenital fatty tumor. Surgical confirmation was present in 11 cases. Diagnosis and determination of the extent of Meckel cave lesions is possible with the use of high-resolution CT.

Carotid Artery, Internal↗

PubMed1980

Structure and electrical properties of eye muscles in cave- and surface-dwelling crayfishes.

The morphologies and passive electrical parameters of fibres in two eye muscles of a surface- and a cave-dwelling crayfish were compared. In the cave-dwelling form the muscles contained fewer fibres, of less diameter, and hence had a smaller cross-sectional area. Current-voltage relationships were similar in both species. Input resistance was higher in the cave-dweller, but the difference was not as great as would be expected on the basis of geometry alone. Accordingly, the specific membrane resistance of muscle fibres in the cave-dweller is 50-60% smaller than that in the surface-dweller. This may account partially for the observation that identified excitatory junctional potentials in muscles of cave- and surface dwellers have similar amplitudes. We conclude that a functional oculomotor system is maintained in cave-dwelling crayfish, and that this system confers some positive selective advantage.

Adaptation, Physiological↗

PubMed1984

Combination chemotherapy for advanced Hodgkin's disease after failure of MOPP: ABVD and B-CAVe.

Between 1973 and 1982, 110 patients with advanced Hodgkin's disease who had had disease progression while receiving MOPP (mechlorethamine, vincristine, procarbazine, and prednisone) chemotherapy or a relapse after a MOPP-induced complete remission were treated with either ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) (58 patients) or B-CAVe (bleomycin, lomustine, doxorubicin, and vinblastine) (52 patients) chemotherapy in concurrent nonrandomized trials. Responses were seen in 39 of 55 (71%) evaluable ABVD-treated patients--21 (38%) complete and 18 partial responses--and in 34 of 48 (71%) evaluable B-CAVe-treated patients--21 (44%) complete and 13 partial responses. The median duration of the ABVD-induced complete remissions is greater than 25 months compared with 24.3 months for B-CAVe-induced remissions. The 5-year actuarial freedom from progression is 8.5% for evaluable ABVD-treated patients and 25% for B-CAVe-treated patients (p = 0.10). Toxicity in the two treatment groups was similar, with only significant thrombocytopenia (platelet count, less than 50 000/mm3) being more common with B-CAVe. Although most patients with Hodgkin's disease refractory to MOPP treatment will respond to either ABVD or B-CAVe chemotherapy, subsequent long-term disease-free survival is unusual. The need for improved treatment programs for this patient group is evident.

Adolescent↗

PubMed2004

Histoplasmosis associated with exploring a bat-inhabited cave in Costa Rica, 1998-1999.

Between October 1998 and April 1999, 51 persons belonging to two separate groups developed acute pulmonary histoplasmosis after visiting a cave in Costa Rica. The first group consisted of 61 children and 14 adults from San Jose, Costa Rica; 44 (72%) were diagnosed with acute histoplasmosis. The second group comprised 14 tourists from the United States and Canada; 9 (64%) were diagnosed with histoplasmosis. After a median incubation time of 14 days, the most common symptoms were headache, fever, cough, and myalgias. Risk factors for developing histoplasmosis included crawling (odds ratio [OR] = 17.5, 95% confidence interval [CI] = 2.3-802) and visiting one specific room (OR = 3.4, 95% CI = 1.0-12.3) in the cave. Washing hands (OR = 0.1, 95% CI = 0.01-0.6) after exiting the cave was associated with a decreased risk of developing histoplasmosis. Histoplasma capsulatum was isolated from bat guano collected from inside the cave. Persons who explore caves, whether for recreation or science, should be aware of the risk bat-inhabited caves pose for developing histoplasmosis, especially if they are immunocompromised in any way.

Adolescent↗

PubMed2001

An early bone tool industry from the Middle Stone Age at Blombos Cave, South Africa: implications for the origins of modern human behaviour, symbolism and language.

Twenty-eight bone tools were recovered in situ from ca. 70 ka year old Middle Stone Age levels at Blombos Cave between 1992 and 2000. These tools are securely provenienced and are the largest collection to come from a single African Middle Stone Age site. Detailed analyses show that tool production methods follow a sequence of deliberate technical choices starting with blank production, the use of various shaping methods and the final finishing of the artefact to produce "awls" and "projectile points". Tool production processes in the Middle Stone Age at Blombos Cave conform to generally accepted descriptions of "formal" techniques of bone tool manufacture. Comparisons with similar bone tools from the Later Stone Age at Blombos Cave, other Cape sites and ethnographic collections show that although shaping methods are different, the planning and execution of bone tool manufacture in the Middle Stone Age is consistent with that in the late Holocene. The bone tool collection from Blombos Cave is remarkable because bone tools are rarely found in African Middle or Later Stone Age sites before ca. 25 ka. Scarcity of early bone tools is cited as one strand of evidence supporting models for nonmodern behaviour linked to a lack of modern technological or cognitive capacity before ca. 50 ka. Bone artefacts are a regular feature in European sites after ca. 40 ka, are closely associated with the arrival of anatomically modern humans and are a key behavioural marker of the Upper Palaeolithic "symbolic explosion" linked to the evolution of modern behaviour. Taken together with recent finds from Klasies River, Katanda and other African Middle Stone Age sites the Blombos Cave evidence for formal bone working, deliberate engraving on ochre, production of finely made bifacial points and sophisticated subsistence strategies is turning the tide in favour of models positing behavioural modernity in Africa at a time far earlier than previously accepted.

Anthropology, Physical↗

PubMed1993

Angiographic differentiation of carotid cave aneurysms from ventral paraclinoid carotid aneurysms of Nutik type.

Although it appears that carotid cave and ventral paraclinoid carotid aneurysms are different types of internal carotid artery (ICA) aneurysms, it can be difficult to differentiate the two on the basis of angiograms, because their locations are very close. The purpose of this study was to review the angiographic findings in 21 cases with carotid cave aneurysms and 7 cases with ventral paraclinoid carotid aneurysms of less than 15 mm in diameter (Nutik aneurysm) operated upon in our unit during the last 14 years, and to discuss the difference between the two groups. The results showed that in the anteroposterior view of the angiogram, all carotid cave aneurysms projected medially in semicircular, or berry shape, while only slight medial projection was noted in 3 cases with Nutik aneurysm, the remainder being superimposed on the ICA. In the lateral view of the angiogram, we found that in 6 of the 7 Nutik aneurysms there was a space between the axilla (area inside the genu of the ICA) and the anterior or anteroinferior wall of the aneurysm. This space was absent in all carotid cave aneurysms since these aneurysms projected inferoposteriorly from the genu of the ICA. It is concluded that predominant medial projection in the anteroposterior view and absence of space in the lateral view are two characteristic features of carotid cave aneurysms which can be used to differentiate them from most Nutik aneurysms.

Adult↗

PubMed2006

Choosy males from the underground: male mating preferences in surface- and cave-dwelling Atlantic mollies (Poecilia mexicana).

Atlantic mollies (Poecilia mexicana) inhabit a variety of surface habitats, but they also occur in a sulfur cave in southern Mexico. We examined male mate choice relative to female body size in the cave population and in the most closely related surface-dwelling population from a nearby river. Males from both populations were either light- or dark-reared and could choose between two differently sized females either on the basis of visual cues in light or on the basis of solely nonvisual cues in darkness. Sexual preferences were estimated from the degree of association. Cave molly males always showed a preference for the larger female, both in light and in darkness. Among the surface males, only light-reared males showed a preference in the visual cues test, but not in darkness. In a control experiment, we demonstrated that male association preferences directly translate into actual mating preferences. Apparently, using visual cues for mate choice is the ancestral state in this system, and using nonvisual cues has evolved as a novel trait in the cave population. We discuss the evolution of nonvisual male mate choice in the context of changed environmental conditions, namely the absence of light, hypoxia, and toxic hydrogen sulfide in the cave.

Animals↗

PubMed1998

Cloning of the alphaA-crystallin genes of a blind cave form and the epigean form of Astyanax fasciatus: a comparative analysis of structure, expression and evolutionary conservation.

In the present study we have analyzed the integrity and expression of the alphaA-crystallin gene, that codes for a major structural component of the lens, in a blind cave form of the teleostean fish, Astyanax fasciatus. This is the first alphaA-crystallin gene cloned from a teleostean fish. Sequence comparison of this cave-form gene with its epigean conspecific and with homologs of distantly related taxa has illustrated conservation of regulatory and coding regions. Although no crystallin proteins are produced in the lens of the cave form, and the mRNA of this gene could not be detected by in situ hybridization of different developmental stages, the promoter region of cave-fish alphaA-crystallin is functionally intact. The deduced amino-acid sequence of the alphaA-crystallin gene of the cave form differs from that of its epigean conspecific at only one position (139). This is within an important, small heat-shock protein-related region, HCR2. A comparison of the 5'-flanking regions of the A. fasciatus alphaA-crystallin gene with the chicken homolog revealed the high conservation of lens-specific regulatory sequences and further demonstrates the evolutionary conservation of this gene. 1988 Elsevier Science B.V.

Amino Acid Sequence↗

PubMed2001

Ancient DNA analysis reveals divergence of the cave bear, Ursus spelaeus, and brown bear, Ursus arctos, lineages.

The cave bear, Ursus spelaeus, represents one of the most frequently found paleontological remains from the Pleistocene in Europe. The species has always been confined to Europe and was contemporary with the brown bear, Ursus arctos. Relationships between the cave bear and the two lineages of brown bears defined in Europe, as well as the origins of the two species, remain controversial, mainly due to the wide morphological diversity of the fossil remains, which makes interpretation difficult [1, 2]. Sequence analysis of ancient DNA is a useful tool for resolving such problems because it provides an independent source of data [3]. We previously amplified a short DNA fragment of the mitochondrial DNA control region (mt control region) of a 40,000-year-old Ursus spelaeus sample [4]. In this paper, we describe the DNA analysis of two mtDNA regions, the control region and the cytochrome b gene. Control region sequences were obtained from ten samples of cave bears ranging from 130,000 to 20,000 years BP, and one particularly well-conserved sample gave a complete cyt b sequence. Our data demonstrate that cave bears split largely before the lineages of brown bears around 1.2 million years ago. Given its abundance, its wide distribution in space and time, and its large morphological diversity, the cave bear is a promising model for direct observation of the evolution of sequences throughout time, extinction periods, and the differentiation of populations shaped by climatic fluctuations during the Pleistocene.

Animals↗

PubMed2001

Nucleotide diversity in populations of balitorid cave fishes from Thailand.

Genetic variabilities in four cave and eight surface species of balitorid freshwater fishes from Thailand were assessed using random amplified polymorphic DNA (RAPD). Cave species have consistently lower RAPD variation than surface species and it is hypothesized that this difference is a function of reduced population size in cave fishes. Indices of nucleotide diversity (pi) were calculated from the RAPD data and are four to five times higher for the surface species than the cave species: 6.4 x 10-3 vs. 1.4 x 10-3. The pi-values for cave fishes are significantly lower than those for surface balitorids and those measured in other species using RAPD/amplified fragment length polymorphism data.

Animals↗

PubMed2004

Analysis of methanotrophic bacteria in Movile Cave by stable isotope probing.

Movile Cave is an unusual groundwater ecosystem that is supported by in situ chemoautotrophic production. The cave atmosphere contains 1-2% methane (CH4), although much higher concentrations are found in gas bubbles that keep microbial mats afloat on the water surface. As previous analyses of stable carbon isotope ratios have suggested that methane oxidation occurs in this environment, we hypothesized that aerobic methane-oxidizing bacteria (methanotrophs) are active in Movile Cave. To identify the active methanotrophs in the water and mat material from Movile Cave, a microcosm was incubated with a 10%13CH4 headspace in a DNA-based stable isotope probing (DNA-SIP) experiment. Using improved centrifugation conditions, a 13C-labelled DNA fraction was collected and used as a template for polymerase chain reaction amplification. Analysis of genes encoding the small-subunit rRNA and key enzymes in the methane oxidation pathway of methanotrophs identified that strains of Methylomonas, Methylococcus and Methylocystis/Methylosinus had assimilated the 13CH4, and that these methanotrophs contain genes encoding both known types of methane monooxygenase (MMO). Sequences of non-methanotrophic bacteria and an alga provided evidence for turnover of CH4 due to possible cross-feeding on 13C-labelled metabolites or biomass. Our results suggest that aerobic methanotrophs actively convert CH4 into complex organic compounds in Movile Cave and thus help to sustain a diverse community of microorganisms in this closed ecosystem.

Carbon Radioisotopes↗

PubMed1979

Pulmonary histoplasmosis associated with exploration of a bat cave.

Approximately 14 days after exploring a limestone cave in northcentral Florida in February 1973, an 18-year-old female developed a respiratory illness with pronounced shortness of breath and cyanosis. The following day, an 18-year-old male presented to the hospital with similar complaints. The association of illness with their recent caving experience prompted further epidemiologic investigation. Twenty-nine members of a church-sponsored youth group explored the implicated cave. Twenty-three of them later became ill with complaints of cough, afternoon fever and sweats, chest discomfort, and dyspnea on exertion. Histoplasmin skin tests were positive in 18 of 24 individuals tested. Serum for complement fixation (CF) was positive in 12 of 26. Testing of area residents revealed a low incidence of skin test and CF positivity (7% and 0%, respectively). That spelunkers are at risk of acquiring pulmonary histoplasmosis has been noted previously; in Florida this has been related to the exploration of caves infested with bats. This is the largest reported outbreak of acute pulmonary histoplasmosis that has been associated with spelunking and further points out that only those individuals who enter the cave are at risk of acquiring the disease, and not those who reside in the surrounding area.

Adolescent↗

PubMed1997

Comparative analysis of Pax-6 sequence and expression in the eye development of the blind cave fish Astyanax fasciatus and its epigean conspecific.

The Pax-6 gene encodes a transcription factor essential for eye development in a wide range of animal phyla. In order to elucidate a possible role of Pax-6 in the eye regression of a blind cave form of the freshwater fish Astyanax fasciatus (Characidae, Teleostei) we investigated the expression of Pax-6 in eyes and brains of different larval stages by in situ hybridization. Pattern, strength, and time course of Pax-6 expression were not altered in the tissues of the cave form when compared to the epigean form. Pax-6 was even expressed in the highly degenerated eyes of late larval stages of the cave form. Comparative sequence analysis of Pax-6 cDNA clones of both forms of Astyanax fasciatus showed the complete integrity of cave fish Pax-6 mRNA. These results suggest that Pax-6 is not involved in the evolutionary process of eye degeneration in this model system of cave-living fishes. Comparison of the Astyanax Pax-6 cDNA with the other available fish Pax-6 sequence from zebrafish revealed putative fish-specific regions of homology. A stretch of 19 N-terminal amino acids is nearly identical on the nucleotide and amino acid levels in both fish species but not present in all other known Pax-6 sequences.

Amino Acid Sequence↗

PubMed2003

Occupational and patient doses in the therapeutic cave, Tapolca (Hungary).

The radon concentration has been measured for three years in a hospital cave used for medical treatment of respiratory diseases. A mean value of the actual equilibrium factor measured in the cave in different seasons was used, different from the commonly used 0.4. The dose contribution to the patients and the staff was calculated using these data. The results of the dose assessment show that the staff in the hospital cave can receive doses up to the dose limit for occupational exposure (20 mSv y(-1)) when working 4 h per day in the cave. Patients receive 0.18-4.22 mSv committed effective dose during the treatment period depending on the exposure periods. The only solution to reduce the dose to the staff seems to be decreasing the time they spend underground, because intensive ventilation would disturb the special microclimate of the cave.

Air Pollutants, Radioactive↗

PubMed1999

Primary lymphoma of Meckel's cave mimicking trigeminal schwannoma: case report.

OBJECTIVE AND IMPORTANCE: We report the first case of primary lymphoma of Meckel's cave. The ability of a lymphoma to mimic a trigeminal schwannoma, both clinically and radiographically, resulted in misdiagnosis and flawed surgical strategy. We discuss the characteristics of a Meckel's cave lymphoma on magnetic resonance images, the predisposing medical conditions that should cause the neurosurgeon to add lymphoma to the normal differential diagnosis, and appropriate management strategies. CLINICAL PRESENTATION: A 40-year-old African-American woman presented with a 5-month history of progressive facial numbness and pain in all three divisions of the left trigeminal nerve. Magnetic resonance imaging revealed a mass in the left side of Meckel's cave, with extension into the lateral compartment of the cavernous sinus, without encasement of the internal carotid artery, through the foramen rotundum into the posterior aspect of the maxillary sinus, and through the foramen ovale into the pterygopalatine fossa. The diagnosis, based on clinical history and radiographic imaging, was schwannoma of Meckel's cave. The patient had a history of systemic lupus erythematosus that had been treated with intermittent steroid therapy. INTERVENTION: The surgical approach selected was a frontotemporal craniotomy with orbitozygomatic osteotomy and anterior petrosectomy. The lesion was totally excised, although the gross intraoperative appearance of the lesion was inconsistent with the preoperative diagnosis, and the pathological examination was unable to establish a histological diagnosis on the basis of frozen sections. Histological diagnosis was confirmed on permanent section after surgery as B-cell lymphoma. Evaluation for other primary sites produced negative results. The patient was then treated with cyclophosphamide (Cytotoxan; Bristol-Myers Oncology, Princeton, NJ), doxorubicin (Adriamycin; Pharmacia & Upjohn, Kalamazoo, MI), vincristine, and prednisone chemotherapy every 3 weeks for six cycles and then by radiation therapy to the affected area. CONCLUSION: The diagnosis of lymphoma should be considered for lesions affecting Meckel's cave in high-risk immunocompromised patients. The presence of an apparent dural tail in an otherwise typical schwannoma is the distinguishing characteristic of a lymphoma. The absence of hyperostosis helps differentiate it from a meningioma. At this point, the preferred surgical strategy is biopsy for diagnosis and then radiotherapy and chemotherapy rather than major cranial base surgery for total resection.

Adult↗

PubMed1995

[An outbreak of acute pulmonary histoplasmosis among travelers to a bat-inhabited cave in Brazil].

Histoplasmosis is known to be endemic in various parts of the world, especially in North and Latin America. In Japan, Histoplasma capsulatum has rarely been isolated from the natural environment. To date, only seven cases of histoplasmosis have been reported in Japan including some that were contracted in foreign countries. Herein, we report the occurrence of acute histoplasmosis among Japanese travelers who were exposed to bat guano in a cave near Manaus, Brazil. A group of 8 Japanese travelers entered a cave for a total of 2 hours in March, 1993. All the visitors had been healthy and had no history of abnormal chest roentgenograms. From 10 to 20 days after the exposure, 7 (87.5%) of the 8 individuals developed abnormal symptoms including fever, malaise, loss of appetite, myalgia, arthralgia, chest pain and dry cough. Five (62.5%) had nodular infiltrative shadows with or without hilar lymphadenopathy in the chest roentgenograms. Eight (100%) of the individuals showed serologic evidence of histoplasmosis. Despite the small number of subjects, this high rate of infection may be related to the fact that the subjects stayed in an enclosed area where air exchange was minimal, at the end of a deep cave infested with numerous bats. The cave involved has never been documented as being endemic for histoplasmosis. The threat of H. capsulatum infection in bat-inhabited caves should be emphasized to travelers and also to physicians.

Adult↗

PubMed1998

Age and origin of carlsbad cavern and related caves from 40Ar/39Ar of alunite

40Ar/39Ar dating of fine-grained alunite that formed during cave genesis provides ages of formation for the Big Room level of Carlsbad Cavern [4.0 to 3.9 million years ago (Ma)], the upper level of Lechuguilla Cave (6.0 to 5.7 Ma), and three other hypogene caves (11.3 to 6.0 Ma) in the Guadalupe Mountains of New Mexico. Alunite ages increase and are strongly correlative with cave elevations, which indicates an 1100-meter decline in the water table, apparently related to tectonic uplift and tilting, from 11.3 Ma to the present. 40Ar/39Ar dating studies of the hypogene caves have the potential to help resolve late Cenozoic climatic, speleologic, and tectonic questions.

Journal Article↗

PubMed2006

Dominant microbial populations in limestone-corroding stream biofilms, Frasassi cave system, Italy.

Waters from an extensive sulfide-rich aquifer emerge in the Frasassi cave system, where they mix with oxygen-rich percolating water and cave air over a large surface area. The actively forming cave complex hosts a microbial community, including conspicuous white biofilms coating surfaces in cave streams, that is isolated from surface sources of C and N. Two distinct biofilm morphologies were observed in the streams over a 4-year period. Bacterial 16S rDNA libraries were constructed from samples of each biofilm type collected from Grotta Sulfurea in 2002. beta-, gamma-, delta-, and epsilon-proteobacteria in sulfur-cycling clades accounted for > or = 75% of clones in both biofilms. Sulfate-reducing and sulfur-disproportionating delta-proteobacterial sequences in the clone libraries were abundant and diverse (34% of phylotypes). Biofilm samples of both types were later collected at the same location and at an additional sample site in Ramo Sulfureo and examined, using fluorescence in situ hybridization (FISH). The biomass of all six stream biofilms was dominated by filamentous gamma-proteobacteria with Beggiatoa-like and/or Thiothrix-like cells containing abundant sulfur inclusions. The biomass of epsilon-proteobacteria detected using FISH was consistently small, ranging from 0 to less than 15% of the total biomass. Our results suggest that S cycling within the stream biofilms is an important feature of the cave biogeochemistry. Such cycling represents positive biological feedback to sulfuric acid speleogenesis and related processes that create subsurface porosity in carbonate rocks.

Biofilms↗