Recessive mutations in RYR1 are a common cause of congenital fiber type disproportion.

The main histological abnormality in congenital fiber type disproportion (CFTD) is hypotrophy of type 1 (slow twitch) fibers compared to type 2 (fast twitch) fibers. To investigate whether mutations in RYR1 are a cause of CFTD we sequenced RYR1 in seven CFTD families in whom the other known causes of CFTD had been excluded. We identified compound heterozygous changes in the RYR1 gene in four families (five patients), consistent with autosomal recessive inheritance. Three out of five patients had ophthalmoplegia, which may be the most specific clinical indication of mutations in RYR1. Type 1 fibers were at least 50% smaller, on average, than type 2 fibers in all biopsies. Recessive mutations in RYR1 are a relatively common cause of CFTD and can be associated with extreme fiber size disproportion.

Mutations in TPM3 are a common cause of congenital fiber type disproportion.

OBJECTIVE: Congenital fiber type disproportion (CFTD) is a rare form of congenital myopathy in which the principal histological abnormality is hypotrophy of type 1 (slow-twitch) fibers compared with type 2 (fast-twitch) fibers. To date, mutation of ACTA1 and SEPN1 has been associated with CFTD, but the genetic basis in most patients is unclear. The gene encoding alpha-tropomyosin(slow) (TPM3) is a rare cause of nemaline myopathy, previously reported in only five families. We investigated whether mutation of TPM3 is a cause of CFTD. METHODS AND RESULTS: We sequenced TPM3 in 23 unrelated probands with CFTD or CFTD-like presentations of unknown cause and identified novel heterozygous missense mutations in five CFTD families (p. Leu100Met, p.Arg168Cys, p.Arg168Gly, p.Lys169Glu, p.Arg245Gly). All affected family members that underwent biopsy had typical histological features of CFTD, with type 1 fibers, on average, at least 50% smaller than type 2 fibers. We also report a sixth family in which a recurrent TPM3 mutation (p.Arg168His) was associated with histological features of CFTD and nemaline myopathy in different family members. We describe the clinical features of 11 affected patients. Typically, there was proximal limb girdle weakness, prominent weakness of neck flexion and ankle dorsiflexion, mild facial weakness, and mild ptosis. The age of onset and severity varied, even within the same family. Many patients required nocturnal noninvasive ventilation despite remaining ambulant. INTERPRETATION: Mutation of TPM3 is the most common cause of CFTD reported to date.

A novel X-linked form of congenital fiber-type disproportion.

We describe a four-generation family with a previously unreported form of congenital fiber-type disproportion that follows an X-linked inheritance pattern. Affected male family members have a striking pattern of weakness. From birth there is marked ptosis, facial weakness, poor sucking, hypotonia, respiratory weakness, and relatively preserved limb strength. Most affected male individuals die of respiratory failure within the first months of life. A mild dilated cardiomyopathy developed in infancy in the sole surviving affected male member of this family. Some carrier female individuals manifest milder signs. We have demonstrated linkage to two regions of the X chromosome, Xp22.13 to Xp11.4 and Xq13.1 to Xq22.1, with a maximum logarithm of odds score of 3.25 in the latter region. We propose that clinical clues can differentiate this disorder from other forms of congenital fiber-type disproportion so that affected families can receive appropriate genetic counseling.

Malaria prevention and control in the United States military.

Malaria continues to be a serious threat to deployed military forces in many areas of the World. United States experiences during, and lessons learned from, World War II, Viet Nam, and Somalia have significantly changed the way that military planners, medical and preventive medicine personnel are facing the malaria challenge. Currently, the US military has a powerful arsenal of educational courses and materials, personal protective measures, and malaria surveillance and control techniques in place to fight malaria. These new tools will hopefully reduce malaria morbidity and mortality during military deployments in the future.

Bacillus sphaericus inhibits hatching of phlebotomine sand fly eggs.

The effect of Bacillus sphaericus, at various concentrations, on hatching of phlebotomine sand fly eggs was examined using laboratory bioassays. Aqueous suspensions of B. sphaericus, strain 2362, inhibited hatching of eggs of Phlebotomus duboscqi and Sergentomyia schwetzi by 95% at concentrations as low as 0.05 and 0.11 mg/cm2, respectively. In contrast, B. sphaericus did not affect the ability of pupae to emerge as adults.

Abundances and nocturnal activities of phlebotomine sandflies (Diptera : Psychodidae) in termite hills and animals burrows in Baringo District; Kenya

The abundance of phlebotomine sandflies was studied in a leishmaniasis endemic area in Baringo District; Rift Valley Province; Kenya. This was based on sandfly behaviors at night in their natural habitats of termite hills and animal burrows. Sandflies were collected with an entry-exit trap which has a sieve fixed at the middle to control sandfly movements. Flies were trapped from 1800-0600 hours. Phlebotomus martini (Parrot) were significantly more abundant in termite hills than in animal burrows (P 0.05). Phlebotomus duboscqi (Neveu-Lemaire) were found to favour animal burrows more than termite hills (P 0.05). Nocturnal movements and activities showed that the majority of the sandflies were exiting from termite hills and animal burrows from 1800-2400 hours while from 2400-0600 hours; the majority of the sandflies were entering termite hills and animal burrows (P0.05). Sergentomyia (Theodor) species showed mixed preferences for these two habitats. Sergentomyia schwetzi (Aldler; Theodor et Pam favoured termite hills more than animal burrows but S. clydei (Sinton) showed great preference for animal burrows. The nocturnal activities or preferences of habitats by phlebotomine sandflies have epidemiological significance in that control measures can be directed to these habitats with a certain degree of accuracy for the vectors of visceral and cutaneous Leishmaniasis in Kenya

Phlebotomine sandflies of Kenya (Diptera: Psychodidae). V. Phlebotomus (Paraphlebotomus) mireillae n.sp.

A new species of the sandfly subgenus Paraphlebotomus Theodor from Kenya is described and named Phlebotomus mireillae. The type locality is Utut Reserve, near Gilgil, Nakuru District. The description is based on 10 males and 10 females reared from individual egg batches of wild-caught females. Males of the new species differ from nine other species of the subgenus by the shape of the aedeagus, which is straight, not curved or hooked. They are separated from the remaining three species by other differences in the aedeagus, and in the style and coxite process. Female P. mireillae have backwardly pointing spines inside the distal quarter of the spermathecal ducts, a character not previously described for phlebotomine sandflies. Additional characters which distinguish females of the new species from others of the subgenus are differences in the pharyngeal armature and spermathecae and the lengths of the third antennal segment and labium.

Phlebotomine sand fly control using bait-fed adults to carry the larvicide Bacillus sphaericus to the larval habitat.

Sugar meals of plant origin are an important component of the sand fly diet. We show that sugar solution baits have potential as vehicles for phlebotomine sand fly control. In the laboratory, adult Phlebotomus duboscqi Neveu-Lemaire and Sergentomyia schwetzi (Adler, Theodor, and Parrot) that have consumed an aqueous sucrose solution containing Bacillus sphaericus Neide toxins and are subsequently eaten by larvae produce significant larval death (P < 0.01). In the field, when vegetation near animal burrows and eroded termite mounds was sprayed with sucrose solution with or without incorporation of the larval toxicant B. sphaericus, 40% of female sand flies fed in situ. Dispersing B. sphaericus-carrier sand flies caused significant larval mortality (P < 0.01) in resting and breeding sites in animal burrows 10-30 m from the sprayed vegetation for 2-12 wk posttreatment. Also, adult sand fly populations breeding and resting inside animal burrows were significantly reduced (P < 0.01) following direct application of the sucrose/B. sphaericus solution to the burrow entrances. This control effect lasted 4-10 wk post-treatment. The effect was not seen for sand fly populations breeding and resting inside eroded termite mounds. This approach may be useful for the application of biological control agents against phlebotomine sand flies in biotypes where larvae and adults use the same habitats.

U.S. Army vector control (preventive medicine) operations during Operation Restore Hope, Somalia.

During the early stages of Operation Restore Hope, three U.S. Army preventive-medicine detachments were deployed to Somalia to counter the disease and non-battle injury threat to deployed forces. The activities of these units are discussed, with an emphasis on the entomology detachment. The preventive medicine (PVNTMED) threat facing deployed forces was considerable, and probably greater than that encountered in any recent operation. This threat is discussed, as are the methods used by the PVNTMED detachments to counter the threat. Vector control and pest management operations of the entomology detachment are highlighted, and how they related to the health and comfort of deployed personnel. These operations ranged from routine mosquito surveillance to large-area vector-control missions using a helicopter-slung pesticide dispersal unit. A variety of "lessons learned" are also discussed, focusing on individual and company-level PVNTMED measures.

Field evaluation of arthropod repellents, deet and a piperidine compound, AI3-37220, against Anopheles funestus and Anopheles arabiensis in western Kenya.

A field evaluation of the repellents N,N-diethyl-3-methylbenzamide (deet) and 1-(3-cyclohexen-1-yl-carbonyl)-2-methylpiperidine (AI3-37220, a piperidine compound) was conducted against Anopheles funestus and An. arabiensis in Kenya. Both repellents provided significantly more protection (P < 0.001) than the ethanol control. AI3-37220 was significantly more effective (P < 0.001) than deet in repelling both species of mosquitoes. After 9 h, 0.1 mg/cm2 of AI3-37220 provided 89.8% and 71.1% protection against An. arabiensis and An. funestus, respectively. Deet provided > 80% protection for only 3 h, and protection rapidly decreased after this time to 60.2% and 35.1% for An. arabiensis and An. funestus, respectively, after 9 h. Anopheles funestus was significantly less sensitive (P < 0.001) to both repellents than An. arabiensis. The results of this study indicate that AI3-37220 is more effective than deet in repelling anopheline mosquitoes in western Kenya.

The effect of immune sera from hamsters immunized with sandfly gut and whole body extract antigens on the fecundity and mortality of Phlebotomus duboscqi (Diptera: Psychodidae).

Phlebotomus duboscqi were fed on hamsters previously immunized with different concentrations of homogenized crude sandfly gut antigen and supernatant obtained from whole body extract. The humoral response in the rodents was quantified at different times post-immunization by the enzyme-linked immunosorbent assay. Sandflies were fed on either immunized or saline control hamsters and the effect of the blood meals on sandfly feeding, survival and fecundity was investigated. The humoral response in immunized hamsters as measured by the presence of P. duboscqi-specific IgG antibodies was significantly greater (P < 0.05) as compared to the controls. This difference was noted in sera collected on 15 and 25 days post-immunization. Sandflies fed on immunized hamsters had a significantly higher mortality (P < 0.05) and decreased egg production (P < 0.05) than those fed on unimmunized control hamsters.

Response of wild Anopheles funestus to repellent-protected volunteers is unaffected by malaria infection of the vector.

A field experiment was conducted to compare the biting behavior of Plasmodium falciparum-infected and uninfected Anopheles on humans using mosquito repellents. Repellent formulations (5% [wt/vol] N,N-diethyl-3-methylbenzamide [deet] or 5% [wt/vol] AI3-37220, a piperidine compound, both in 100% ethanol, or 100% ethanol alone [as a control]) were applied to the lower legs of 3 collectors in each of 4 houses. Collectors caught mosquitoes over 6 collection nights. Mosquitoes were collected into vials after they initiated probing on the leg of a collector. Infected females made up the same proportion of the Anopheles funestus populations biting either repellent-protected or unprotected individuals. We conclude that repellent formulations are equally effective against Plasmodium-infected and uninfected An. funestus.

The chemotactic effect of Phlebotomus duboscqi (Diptera: Psychodidae) salivary gland lysates to murine monocytes.

The possibility that salivary gland lysates of Phlebotomus duboscqi are able to attract vertebrate monocytes was investigated. In vitro studies showed that salivary gland lysates of P. duboscqi, the vector of Leishmania major in Kenya, are chemotactic to mouse peritoneal monocytes. This attraction of monocytes by vector salivary gland lysates may form part of the mechanisms through which sandfly saliva ensures successful parasitization of macrophages in a susceptible host by Leishmania parasites.

Experimental immunization against cutaneous leishmaniasis using Leishmania major subcellular fractions alone or in combination with Phlebotomus duboscqi gut antigens.

Leishmania major-derived flagella and nuclear fractions, and a combination of flagella and sand fly gut antigens were assessed for protection against L. major infection in BALB/c mice. Mice immunized with flagella antigen developed a severe infection while nuclear fraction-immunized animals were partially protected at the onset of infection from week 1 to 4 post challenge. A combination/cock tail of flagella and sand fly gut antigens protected animals at a later stage from week 10 to 14 post-infection. Surviving cocktail-immunized animals did not ulcerate, and parasites did not metastasize to the viscera. These results provide preliminary evidence of the potential of a cock tail antigen derived from Leishmania flagella and sand fly gut in the protection against cutaneous leishmaniasis caused by L. major.

Phlebotomine sand fly (Diptera: Psychodidae) control using a residual pyrethroid insecticide.

Cyfluthrin was evaluated in the field as a residual insecticide to develop a new strategy for control of Old World phlebotomine sand fly vectors of leishmaniasis, which live and rest inside termite mounds and animal burrows. This insecticide was evaluated as a residual spray in Baringo District, Kenya, during 1993. Termite mounds and animal burrows were treated with a cyfluthrin/corn oil mixture (1.5% AI) using an 8-liter hand-pumped sprayer. Treatment of animal burrows and termite mounds with cyfluthrin provided control of sand flies inside these structures for 12 wk. Numbers of sand fly adults collected in light traps were reduced by up to 90% for 2 wk following treatment. This indicates that cyfluthrin provides short-term area control of adult sand flies when applied to termite mounds and animal burrows.

Phlebotomine sandflies associated with households of human visceral leishmaniasis cases in Baringo District, Kenya.

A 12-month field study on sandflies was conducted from April 1992 to March 1993 at three locations in Baringo District, Rift Valley Province, Kenya. Study sites were selected based on their close proximity to the households of three patients who had had parasitologically confirmed visceral leishmaniasis in 1988, 1990 or 1991. Sandfly populations were highest during the two rainy seasons, April-June and November-December. A significant association was detected between the monthly abundance of sandflies and rainfall in the previous month. A significantly higher proportion of females than males was collected in light traps than on sticky paper traps set in termite mounds or animal burrows: approximately twice as many males as females were collected from the sticky paper traps whereas twice as many females as males were collected in light traps. Over 10% of the female sandflies collected from animal burrows and termite mounds were gravid, indicating that these flies were seeking oviposition sites at these locations. A total of 2231 sandflies was collected and five females were found to have flagellates in their midguts. The flagellates cultured from four Sergentomyia spp. were tentatively identified as Crithidia sp. by cellulose acetate electrophoresis (CAE). The promastigotes from the one Phlebotomus martini female found with an infected midgut were identified as Leishmania donovani by CAE.(ABSTRACT TRUNCATED AT 250 WORDS)

Laboratory evaluation of repellents against four anopheline mosquitoes (Diptera: Culicidae) and two phlebotomine sand flies (Diptera: Psychodidae).

Deet, the lactone CIC-4, and the piperidine compounds A13-37220 and A13-35765 were evaluated for initial repellency against laboratory-reared Anopheles albimanus Wiedemann, An. freeborni Aitken, An. gambiae Giles, An. stephensi Liston, and Phlebotomus papatasi (Scopoli) using a dose-response testing procedure on human volunteers. In addition, deet and CIC-4 were tested against Lutzomyia longipalpis (Lutz & Neiva). In general, the repellency of A13-37220, A13-35765, and CIC-4 was not markedly different from that of deet against each species tested; however, the different species varied greatly in response to the repellents. Overall, An. stephensi, L. longipalpis, and P. papatasi were the most sensitive, and An. albimanus the most tolerant species. The four repellents subsequently were tested against An. stephensi and An. albimanus to determine the duration of repellency. AI3-37220 provided effective (> 90%) protection against An. stephensi bites for 7 h, whereas deet, AI3-35765, and CIC-4 provided 6, 5, and 3 h of protection, respectively. Each of the four compounds provided < 1 h of protection against An. albimanus bites.

Laboratory and field evaluation of five repellents against the black flies Prosimulium mixtum and P. fuscum (Diptera: Simuliidae).

Deet (N,N-diethyl-3-methyl-benzamide), the lactone CIC-4 ([2-hydroxy-methyl-cyclohexyl] acetic acid lactone), the USDA Proprietary Chemicals AI3-37220 (1- [3-cyclohexen-1-ylcarbonyl]-2-methylpiperidine) and ++[3-35765 (1-[3-cyclohexen-1-ylcarbonyl] piperidine), and the U.S. military extended duration repellent formulation (EDRF) of deet were evaluated for repellency in the laboratory and field against the black flies Prosimulium mixtum and P. fuscum. CIC-4, AI3-37220, and AI3-35765 were as effective as deet at repelling P. mixtum and P. fuscum in laboratory and field experiments. Only the EDRF provided significantly longer protection than the deet standard against these black flies in the field.